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Framing the fl ow
Innovative Approaches to Understand, Protect and
Value Ecosystem Services Across Linked Habitats
Silvestri, S., Kershaw, F. (eds.), 2010. Framing the fl ow:
Innovative Approaches to Understand, Protect and Value
Ecosystem Services across Linked Habitats, UNEP World
Conservation Monitoring Centre, Cambridge, UK
Copyright © United Nations Environment Programme 2010
ISBN 978-92-807-3065-4
February 2010 DEW/1243/CA
Printed by Seacourt Limited
Disclaimer
The contents of this report do not necessarily refl ect the
views or policies of UNEP or contributory organisations.
The designations employed and the presentations do not
imply the expression of any opinion whatsoever on the part
of UNEP or contributory organisations concerning the legal
status of any country, territory, city, company or area or its
authority or concerning the delimitation of its fronteirs or
boundaries.
Framing the fl ow:
Innovative Approaches to Understand, Protect and
Value Ecosystem Services Across Linked Habitats
Silvia Silvestri
Francine Kershaw
2 Framing the Flow
UNEP promotes environmentally sound
practices globally and in its own activities.
This publication is printed on recycled paper,
FSC certifi ed, post-consumer waste and chlorine-
free. Inks are vegetable-based and coatings are
water-based. Our distribution policy aims
to reduce UNEP’s carbon footprint.
Preface 3
Preface
Marine, coastal and freshwater ecosystems are complex
and characterised by an array of ecological functions and
processes essential to the regulation and continued pro-
vision of ecosystem services of direct or indirect benefi t
to human welfare and society. Ecosystem services fl ow
from their source to sink across both land- and seascapes,
and call for the integrated management of connected
ecosystems to optimise the fl ow of these services and
benefi ts.
This publication highlights the interconnectivity and link-
ages between coastal ecosystems (mangroves, coral
reefs, seagrasses, estuaries, and lagoons) across environ-
mental, economic, social, and management contexts. It
presents innovative approaches to better understand,
protect and value ecosystems services across linked
habitats, informing the trade-off of different land-use
management decisions and the effects on healthy sys-
tems from drawing on ecosystem services from linked
habitats.
Worrying fi ndings are presented on the impacts of ra-
pid natural and human induced change on the health of
coastal ecosystems, the implications of these disruptions
for ecosystem functioning and the delivery of ecosystem
services.
At least 35% of mangroves and 29% of seagrasses have
been lost in the last two decades, while coral reefs are
estimated to have lost up to 19% of their original area on
a global scale. A further 15% of coral reefs are seriously
threatened with loss within the next 10-20 years, and 20%
are under threat of loss in 20-40 years, with potentially
negative impacts on fi sheries and food security for vul-
nerable coastal populations.
Understanding the benefi ts of maintaining and indeed
restoring the fl ow of ecosystem services across the
complete supply chain can result in reducing risk and
securing the continued supply of those services.
Finally, information on ecosystems services fl ows can allow
planners to make the case for truly integrated management
approaches, especially those bridging the divide between
terrestrial watershed management, coastal zone manage-
ment and marine ecosystems-based management, by
stressing how an integrated approach can deliver multiple
benefi ts to society and the environment.
This report presents further evidence of the need to develop
appropriate economic and governance frame works that
best protect the essential services from natu ral ecosystems
that human populations will need for the future.
Achim Steiner
UNEP Executive Director
United Nations Under-Secretary General
4 Framing the flow
Executive Summary 5
Executive Summary
This publication presents a framework for an understanding
of the connectivity between tropical coastal ecosystems
(including mangroves, seagrasses and coral reefs) ac-
ross environmental, economic, social, and management
contexts. It presents innovative approaches to better
understand, protect and value ecosystem services across
linked habitats, and to allow informed trade-offs between
different land-use management decisions and consequent
changes in different ecosystem services.
Coral reefs, mangroves, seagrasses and nearshore ter-
restrial ecosystems are highly interconnected by their
physical and biological dependence on each other.
The importance of this interdependence to ecosystem
function and service provision is becoming increasingly
recognised, particularly in the context of the disruptive
impacts of human drivers of change.
Tropical terrestrial and coastal marine ecosystems
provide a wide range of benefi ts and services and can
be assigned substantial economic value. The ‘fl ow’
of these services can be traced over space and time,
linking producing and consuming systems and human
communities. Quantifi cation of these fl ows is essential in
order to defi ne the ultimate benefi ciaries of services, a
process which can be achieved through a combination of
biophysical and socio-economic analysis and modelling.
One example of this approach would be the valuation of
the fl ow of ecosystems services that can be supported by
a ‘with or without’ scenario, using a ‘what if’ approach, i.e.
what may happen if we stop the fl ow and modify the links
between ecosystems?
In converting ecosystem functions (regulation, habitat,
production, and information) to a quantitative value,
among many aspects to be considered are: the evidence
for non-linearity in ecosystem services; the spatial extent
of the entire linked ecosystem responsible for service
delivery; the future use of the resources; and variation in
value according to the scale considered. Spatial mapping,
combined with a defi nition of benefi ts and benefi ciaries,
can be a useful tool to support the valuation process and
identify regions more likely to provide higher or lower
levels of value.
Recognising the dynamic links between terrestrial, coastal
and marine ecosystems, and how ecosystem services
fl ow across these systems can help businesses improve
their environmental performance, reduce risks and costs,
and gain public support. Adopting the concept of fl ows of
ecosystem services as part of business planning involves
acknowledging the spatial and temporal coupling
between areas where ecosystem services are generated
and areas where the services are being used. It also
involves understanding the mechanisms through which
ecosystem services fl ow from source to points of usage.
Each of these three components of ecosystem service
– fl ows, source and use – are crucial for maintaining a
healthy supply of critical ecosystem services, and there-
fore information about them is necessary to inform
business decision-making.
Businesses have many additional reasons for ensuring
that sources of ecosystem services are maintained
over time. Maintaining access to these resources and
guaranteeing their sustainable use enables businesses to
operate at a desirable level of productivity, keeping costs
of inputs low, avoiding scarcity, and reducing risks to the
supply chain.
The awareness of the linkages between coastal eco-
sys tems and the integration of the fl ow concept in
management processes could lead to a more com-
prehensive approach which includes recognition of the
need to protect the natural capital that generates services,
together with the underlying ecological connections
that regulate the fl ow of these benefi ts across systems.
Not taking into account the interconnections between
ecosystems and the fl ow of ecosystem services among
them carries the signifi cant risk of individual ecosystems
deteriorating despite management efforts, with the con-
sequence of loss in services and the potential to cause
some ecosystems to approach their ecological tipping
points. Information on fl ows allows planners to make
the case for truly integrated management approaches,
especially those bridging the divide between watershed
management, coastal zone management and marine
ecosystem-based management, by exhibiting how this
improves the effi ciency of overall management.
The transboundary nature of ecosystem service fl ows
holds inherent challenges for the policy makers as new,
holistic and cross-sectoral approaches must be developed
to address the needs of complex groups of stakeholders
and agencies. In these novel governance structures, the
availability of simple, accessible and comprehensive
6 Framing the flow
capacity to appropriately manage and preserve ecosystems
and the services they provide. There remains a general
lack of integration of knowledge of ecosystem services
into development policy and the concept of ecosystem
fl ows may help to fi ll this gap.
4 Preface
information will be critical to support informed decision-
making. Policy and decision makers will need to incorporate
appropriate tools for resolving confl icts and trade-offs.
The ability of policy makers to address the key challenge
of reducing poverty worldwide is dependent on building the
Introduction 7
3 Preface
5 Executive Summary
8 Introduction
9 Chapter 1: Conceptualising
Ecosystem Benefi ts across
Land- and Seascapes
26 Chapter 2: Capturing and
Quantifying the Flow
of Ecosystem Services
34 Chapter 3: Valuing
Ecosystem Services
of Coastal Habitats
41 Chapter 4: Application
for Industry and Business
44 Chapter 5: Implications
for policy makers
and practitioners
50 Key Recommendations
52 Glossary
55 Acronyms
56 Contributors and Reviewers
57 References
61 Other Relevant Reading
Contents
8 Framing the flow
Introduction
Most of the world ‘megacities’ (defi ned as more than 10
million inhabitants) are in coastal areas (Nicholls, et al.,
2007; Engelman, 2009). This is no accident as coastal
ecosystems deliver a wide range of bene fi ts to human
society, including fi sheries, water fi ltration, re duction of
pollution impacts, soil formation, pro tection from coastal
erosion, buffering of the effects of extreme weather
events, recreation, tourism, support to industry, and a
means of transport (Nellemann et al., 2009). Owing to
the provision of these services, coastal eco systems have
been attributed high economic worth through the rapidly
developing fi eld of ecosystem service valuation. Mangrove
systems are worth an estimated US$4,290 annually per
hectare; estuaries, lagoons and seagrasses provide bene-
fi ts of around US$73,900 per year per hectare, while the
annual value of a hectare of coral reefs is estimated to be
US$129,000, among the most economically valuable of
all ecosystems (TEEB, 2009).
These ecosystems are widely distributed, with 44% of
countries containing coral reefs and around half having
mangroves, both systems principally located in the
tropics with Southeast Asia a major centre. Australia and
Indonesia have approximately 50,000km
2
of reef each,
accounting for around one third of the world’s entire
reef system. About one third of the world’s mangroves
are also found in Indonesia (UNEP, 2006). Seagrasses
are estimated to cover globally about 180,000 km2 in
tropical and temperate areas (Green & Short, 2003).
However, tropical coastal ecosystems are facing a wide
range of threats that are disrupting connectivity and eco-
system function. Globally, at least 35% of mangroves and
30% of seagrass have been lost in the last two decades,
while coral reefs are estimated to have lost about 20%
of their original area (Valiela et al., 2001; Waycott et
al., 2009). A further 15% of coral reefs are seriously
threatened with loss within the next 10-20 years, with
potentially negative impacts on fi sheries and food security
of vulnerable coastal populations (Wilkinson, 2008).
Coral reefs, mangroves, seagrasses, and nearshore ter-
restrial ecosystems are highly interconnected by their
physical and biological interdependence, with pathways
and processes that generate ecosystem services ‘fl ow-
ing’ from one habitat to another. There is increasing
recognition of the importance of the interdependence
between ecosystems, and the role of these linkages
in overall ecosystem function. There is need to identify
and manage these linked habitats as a single ecosystem
‘unit’ in order to preserve the pathways of ecosystem
service fl ow between them and to maintain the integrity
of ecosystems and optimise provision of human benefi ts.
This publication – Framing the fl ow – seeks to promote
improved management for sustainability by considering
coastal ecosystem processes in terms of the generation,
fl ow and delivery of services across linked habitats and
the broader regional landscape. Viewing ecosystem ser-
vices in this way has benefi ts and implications not only for
biologists and ecological modellers, but also for the indus-
try and business sectors, policy makers and practitioners
in the fi eld.
We provide a comprehensive overview of these perspec-
tives, building the concept of ecosystem benefi t fl ow,
introducing recent modelling techniques designed to fac-
ilitate analysis of benefi t fl ows, and outlining ap proaches
to economic valuation. Advantages of integrating the eco-
system fl ow concept into industry and business strategies
are then presented, and implications for policy makers
and practitioners are discussed. Finally, key recom men-
dations provide a platform for progressing further work
in this fi eld.
Conceptualising Ecosystem Benefits Across Land- and Seascapes 9
Chapter One
Conceptualising Ecosystem Benefi ts
Across Land- and Seascapes
Ecosystem services provided by coastal
habitats
Ecosystem services are defi ned as the direct or indirect
contributions of ecosystems to human welfare (MA,
2005). One cannot speak of ecosystem services – or try
to measure them − without linking them in some way to
the benefi ts they provide to society.
The Millennium Ecosystem Assessment (MA, 2005) iden-
tifi ed a number of common services derived from coastal
ecosystems: food, biodiversity, nutrient cycling and
fertility, climate regulation, disease control, fl ood/storm
protection, and cultural amenity. These services often
rely on ecological pathways connecting coastal systems
– including estuaries, intertidal areas, lagoons, kelp for-
ests, mangroves, rock and shell reefs, sea grasses, and
coral reefs – with the deep ocean or mainland.
Supply of these ecosystem services relies absolutely on
the ecological processes that characterise the ecosystem
and its operation, and which help maintain its integrity
following disturbance or stress. A recent report of the US
EPA Science Advisory Board on “Valuing the Protection of
Ecosystems and Services” defi nes ecosystem functions
or processes as
the characteristic physical, chemical, and biological
activities that infl uence the fl ows, storage, and trans-
formation of materials and energy within and through
ecosystems. These activities include processes that
link organisms with their physical environment (e.g.
Types of service provided by coastal habitats
Provisioning services provide human populations with direct, harvestable benefi ts such as food, water, building
materials, and pharmaceutical compounds.
Supporting services enable ecosystems to be maintained, for example, through soil formation, carbon storage and
the maintenance of biodiversity. These services underpin provisioning services and so contribute indirectly to human
welfare.
Regulating services control physical or biological processes within the ecosystem which enhance human welfare or
qual ity of life, for example, climate and water regulation, the control of pests and disease (i.e. through bio logical control
or physical barriers to their spread), and control of soil erosion and natural hazards.
Socio-cultural services are highly context-specifi c and provide aesthetic, religious, spiritual, recreational, tradi tional,
or intellectual values ascribed by a community to a natural system.
primary productivity and the cycling of nutrients and
water) and processes that link organisms with each
other, indirectly infl uencing fl ows of energy, water, and
nutrients (e.g. pollination, predation and parasitism).
These processes in total describe the functioning of
ecosystems. (EPA-SAB-09-012, May 2009)
Increasing our understanding of these processes is es-
sential to comprehending how ecosystem services are
generated and how they transfer or ‘fl ow’ between eco-
system components and other linked ecosystems. This
knowledge is essential to understanding the be haviour
of any given service and is key to planning for effective
management of ecosystem services.
The large scale geophysical elements of ecosystems can
be as important for service delivery as the organisms
present. For example, mangroves provide coastal protec-
tion from fl ooding but their capacity to do so during a
disturbance depends both on ecosystem characteristics
and on the environmental conditions surrounding the
mangrove system, such as topography, slope, bathymetry,
and geomorphology.
Ecosystem function and connectivity for
coastal tropical habitats
Ecosystems are highly connected, linked by fl ow of
energy and material so that processes initiated upstream
may provide services in downstream systems. The con-
ceptual model in Figure 1 provides an illustration of these
relationships.
10 Framing the flow
Figure 1 – Diagram showing the complex fl ows of
materials and energy characteristic of coastal eco-
systems. The capacity of systems to provide one service,
e.g. clean water provision, can be impacted by excess use
of another, e.g. waste disposal. Over-use of services can
act as a driver of ecosystem change.
Aquatic systems are strongly connected by the hydro-
logical cycle. Water fl ows downstream from high lands to
the sea, residing for a time as surface water, river fl ow
or groundwater, before evaporating again to atmospheric
water. Where ecosystems are strongly linked, defi ning
their boundaries, and the spatial and temporal scales
involved in processes that deliver ecosystem services,
demands careful consideration. The smaller the system,
the easier it is to measure the delivery of goods and
services within it, but it may be harder to manage or
predict changes in rates of fl ow of these services. If
the goal is to maintain fi sheries production in a coastal
bay, it may not be suffi cient to identify where the small
fi ngerlings come from and protect their nursery habitat in
adjacent marshlands or mangroves; it could be a priority
to protect the quality and quantity of fresh water input
from higher up in the catchment, aiming to ensure that
appropriate salinity and nutrient levels are maintained. A
subsequent goal might be to understand the dynamics
by which these fry support populations of other fi shes,
perhaps also fi shery target species, and other animal
groups that feed and are dependent on them. Thus, a key
requirement is to draw ecosystem boundaries suffi ciently
Conceptualising Ecosystem Benefits Across Land- and Seascapes 11
R. JEERAWAT SIRIWIKUL -UNEP / Still Pictures
12 Framing the flow
large to capture the ecosystem functions and processes
that produce, regulate or otherwise transform the
ecosystem services of interest.
Coastal ecosystems intersect land and sea and provide
both terrestrial and marine ecosystem services. This
property makes them an appropriate focus for a study
on the fl ow of ecosystem services. The high degree of
connectivity in coastal ecosystems, however, creates
challenges when attempting to attribute ecosystem
service reduction to just one driver. Furthermore, when
assessing individual consequences of change, the re-
percussions on ecosystem services may vary with the
magnitude, periodicity and continuity of the driver.
Coral reefs, mangroves, seagrasses, and other nearshore
ecosystems are highly connected by their physical and
biological dependence on each other (Nagelkerken et
al., 2000; Nagelkerken et al., 2002). With increasing re-
cognition of this, scientists and conservation managers
have started to place a greater emphasis on protecting
the connectivity and fl ow between these ecosystems
as essential to both biodiversity conservation and main-
tenance of ecosystem services.
Moving from land to sea, it becomes very evident that
nearshore terrestrial ecosystems play an important
role in the health of tropical marine ecosystems. De-
forestation or conversion of forested land can cause
increased sedimentation and pollution in mangrove, sea-
grass and coral reef habitats (McCulloch et al., 2003;
Fabricius, 2005). Land use changes can also affect the
fl ow regime of rivers, changing the quantity and timing
of freshwater discharge to coastal systems (Ellison &
Farnsworth, 2001). Although mangroves thrive in a saline
environment, some freshwater input is needed for growth
(Ellison & Farnsworth, 2001), and changes in upland
hydrology, following dam construction, for example, can
cause cascading effects across mangrove, seagrass and
coral reef ecosystems.
Source: compiled by UNEP-WCMC, 1997.
Mangroves
Coral reefs
Source: compiled by UNEP-WCMC, 2003.
Seagrasses
Source: compiled by UNEP-WCMC, 2005.
14 Framing the flow
Figure 2 – Diagram showing the ecosystem connectivity between mangroves, seagrasses and coral reefs. Ecological
and physical connectivity between ecosystems is depicted for each ecosystem: terrestrial (brown arrows), mangroves
(green arrows), seagrasses (blue arrows), and coral reefs (red arrows). Potential feedbacks across ecosystems from the
impacts of different human activities on ecosystem services are also shown (yellow arrows).
Threats to connectivity and ecosystem function
Tropical terrestrial and coastal marine ecosystems
are facing an array of threats that are disrupting
connectivity and ecosystem function. Threats include
habitat conversion and destruction, changes in nutrient,
sediment, or freshwater inputs, and reduction in fi sheries
production. In general, depending in part on the number
and extent of freshwater catchments draining to them,
coastal ecosystems suffer cumulative impacts from
multiple drivers of change.
At least 35% of mangroves have been lost in the last two
decades to a combination of mariculture, agriculture,
urbanisation, and collection of fuel wood (Valiela et al.,
2001). Similarly, around 30% of total seagrass area has
been lost (Waycott et al., 2009) while coral reefs are
estimated to have declined by up to 80% since the 1970s
in the Caribbean (Gardner et al., 2003) with at least 1%
annual loss in the Indo-Pacifi c over a similar period (Bruno
& Selig, 2007).
Loss of mangrove and seagrass leads to increased sediment
and nutrient input to coral reefs, leading to degradation and
loss of coral and potentially negative impacts on fi sheries,
which may in turn threaten the food security of vulnerable
coastal populations. Loss of coral habitat also reduces the
natural coastal defence service they provide leading to
increased vulnerability. The resulting loss of infrastructure
or of pristine coral habitat needed for profi table diving
operations can reduce tourism revenue. Additionally, all
of the major coastal tropical habitats are experiencing
signifi cant threats from climate change-related impacts
and over-fi shing, as well as a variety of other localised
stressors (Halpern et al., 2008). Case studies illustrated on
fi gures 3 and 4 provide the opportunity to further explore
examples of these key stressors.
Y
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Y
Coral reef
Offshore
waters
Seagrasses
Mangroves
Land
Decreased storm
buffering
Export of fish
and invertebrate
larvae and adults
Binding sediments
Absorb inorganic
nutrients
Binding sediments
Absorb inorganic
nutrients
Slow freshwater
discharge
Sediments
Habitat destruction
Changes in nutrients, sediments
and freshwater outputs
Loss of mangrove
and seagrass
habitat
Socio-economic
changes for coastal
populations
Increased sedimentation
and nutrient imput
Decreased fisheries, decreased
revenues from tourism, and
decreased storm buffering
Loss of coral reef habitat
Nutrients
Freshwater
discharge
Decreased storm
buffering and increased
coastal erosion
Export of
invertebrate and
fish larvae
Fish and invertebrate
habitat (adult
migration)
Storm buffering
Storm buffering
Fish and
invertebrate
habitat
Export of organic
material and
nutrients for nearshore
and offshore food webs
Export of organic
material and nutrients
for nearshore and
offshore food webs
Export of
invertebrate and
fish larvae
Fish and invertebrate
habitat (adult
migration)
Ecosystem connectivity and impacts on ecosystem services from human activities
Source: see chapter references
Impacts
Ecosystem
connectivity
Conceptualising Ecosystem Benefits Across Land- and Seascapes 15
Coral reefs: Ecosystem function and connectivity
Coral reefs provide essential services and ecological linkages through seagrasses and mangroves back to terrestrial
habitats. Coral reefs exist in a tight ecological relationship with seagrasses and mangroves, serving as the adult or
foraging habitat for countless reef fi sh and invertebrates. Larvae from these populations are often exported back
to seagrasses or mangroves for some stage of their lifetime and may migrate between all three habitats. These
fi sheries are both biologically and economically important. Sustainable coral reef fi sheries generate US$2.4 billion
per year in revenue for Southeast Asia alone (Burke et al., 2002). In addition, coral reefs provide the fi rst physical
structure for shoreline protection and erosion, slowing the impact of wave action from storms. By reducing storm
impacts, coral reefs may not only protect seagrass and mangroves, but also human populations and infrastructure
on the coast (Kunkel et al., 2006; Barbier et al., 2008).
Mangroves: Ecosystem function and connectivity
Bridging the land-sea interface, mangroves are a critical intertidal habitat in the tropics. As fresh water, nutrients
and sediments fl ow from inland sources, mangroves bind sediment, absorb inorganic nutrients and physically slow
freshwater discharge (Valiela et al., 2001). They also provide critical buffering of the shoreline from erosion by storms
(Barbier et al., 2008), which can dramatically protect both inland infrastructure and coastal populations in low-elevation
areas (Das & Vincent, 2009). Several studies have also found that mangroves can affect the presence and biomass of
coral reef fi sh and other coastal tropical fi sheries because they provide important nursery and refuge habitat for juvenile
and adult fi sh (Nagelkerken et al., 2002; Mumby et al., 2004; Aburto-Oropeza et al., 2008).
Seagrasses: Ecosystem function and connectivity
Seagrass beds are an essential ecosystem in the tropical seascape. Seagrass beds grow extensively throughout both
temperate and tropical regions, primarily occupying subtidal areas, but sometimes extending into the intertidal (Williams
& Heck, 2001). Like mangroves, seagrasses stabilise sediments (Orth et al., 2006), sequester carbon (Duarte et al.,
2005), and play a key role in nutrient cycling (Williams & Heck, 2001). As one of the most productive ecosystems in the
world (Waycott et al., 2009), they export a substantial amount of particulate organic matter as well as plant and animal
biomass, supporting or subsidising coastal and benthic food webs (Heck et al., 2008). Like mangroves, seagrasses are
also an important nursery and foraging habitat for several taxa including invertebrates, fi sh, birds, and mammals during
one or more of their life stages (Williams & Heck, 2001). Many of these species, like dugongs, manatees and several
species of sea turtles, are highly threatened by lack of habitat, overfi shing or reduced water quality (Hughes et al., 2009).
In addition, seagrass extent also affects the diversity and biomass of several species of coral reef fi sh (Nagelkerken et
al., 2002; Dorenbosch et al., 2005; Verweij et al., 2008; Hughes et al., 2009).
16 Framing the flow
Case Study 1: Ecosystem services reduction as a consequence of coastal development:
The Cienaga Grande de Santa Marta (CGSM), a UNESCO Biosphere reserve and a Ramsar site in the Columbian Caribbean,
has an area of 4,280km
2
and comprises a complex coastal lagoon and surrounding ecosystems, including fresh and marine
waters, mangrove forests, savannahs, transition forests, grasslands, dunes and beaches, and anthropogenic agricultural
landscape (Figure 3). The CGSM was previously almost entirely dominated by mangrove forests (Restrepo et al., 2006),
with at least 511km
2
of mangrove forest in the 1950s. Since this period, 300km
2
have been lost as a consequence of
human intervention. These include: interruption of sea-land circulation by the construction of a road linking two of the
most important cities in the Colombian Caribbean coast; decrease of fresh water input following an increase in river-
borne sediment; deterioration of water catchments including the Magdalena river; direct domestic and sewage discharges
into the system; contamination from agro-industrial discharges from banana plantations nearby and from the extensive
Magdalena catchment; direct mangrove harvest; and unplanned settlement within mangrove areas. Consequences of
ecosystem deterioration in CGSM have been evident for some years among local and surrounding communities.
Figure 3 – Map showing the air and water circulation at Cienaga Grande de Santa Marta, Colombian Caribbean.
The lagoon, a Ramsar site and a UNESCO Biosphere reserve, supports several ecosystems and is home for more than
516 species, providing direct services to more than 350,000 people including more than 5,000 artisanal fi shers. The
ecological equilibrium which depends upon the circulation of water and sediments between land, sea and the several
channels which drain the system has been severely interrupted.
Conceptualising Ecosystem Benefits Across Land- and Seascapes 17
Vilardy (2008) has identifi ed over 40 potential ecosystem services that the Cienaga Grande de Santa Marta could be
providing to neighbouring communities and the broader Caribbean basin.
Since the late 1990s the Colombian government and several environmental agencies have instigated programmes
aiming towards the recovery of the CGSM, re-establishing the natural circulation of water and nutrients and restoring
the CGSM ecosystem services. Mangrove forest restoration has progressed slowly but fi sheries catch seemingly
improved between 2001 and 2006 (Viloria & Troncoso, 2008).
Ecosystem services directly associated with the CGSM
(Ramirez, 2008):
• Infl uence climate and precipitation regimes
• Carbon sink
• Coastal protection
• Buffer zone
• Purifi cation/fi ltration of pollutants
• Water and food provision
• Materials/products provision (salt, timber, building
material)
• Recreation
• Habitat and refuge for permanent and migrant species
• Scientifi c value
• Pest control
• Nutrients and sediments discharge and exchange
• Habitat for 516 species of animal, including 35 migrant
birds
Consequences of CGSM ecosystem deterioration
(Ramirez, 2008):
• Lagoon eutrophication
• Hyper-salinisation of soils leading to soils not suitable
for ecosystem restoration or subsistence agriculture
• 70% of the original mangrove forest eliminated
• Decrease of fi sheries and massive fi sh mortality events
• Human health deterioration
• Increased poverty in the neighbouring communities
• Unplanned urban growth in towns near and within
the system
18 Framing the flow
Case Study 2: Ecosystem services reduction as a consequence of offshore activities
The following non-tropical case study illustrates connectivity between deep sea and shoreline ecosystems.
Sea otters and killer whales have long shared habitat around the west-central Aleutian archipelago. Recently, killer
whales have begun to feed on sea otters, possibly as a result of a reduction in more usual food sources such as Steller’s
sea lion and harbour seal, populations of both having collapsed across the northwest Pacifi c, probably because of
reduced availability of their prey fi sh (Estes et al., 1998).
Figure 4 – Changes in sea otter abundance over time at several islands in the Aleutian archipelago and concurrent
changes in sea urchin biomass, grazing intensity and kelp density measured from kelp forests at Adak Island.
Red arrows represent a strong trophic interaction, green arrows represent weak trophic interaction (Source: Estes et al.,
1998).
Killer whale predation appears to have reduced sea otter populations and led to an increase in sea urchins, formerly
regulated to some extent by otter predation. Sea urchins graze on kelp, but the increase in urchin populations has been
accompanied by a twelvefold decrease in kelp biomass (Estes et al., 1998).
Among the several ecosystem services provided by kelp forests are wave attenuation and coastal protection, hence kelp
forest reduction may contribute to coastal erosion in the area (Norberg, 1999).
Here, the change in predatory pattern of the killer whale could be identifi ed as a natural driver which has led to a change
in ecosystem functioning. However, there are a range of indirect drivers which could be infl uencing the changes in this
ecosystem, including the anthropogenic reduction of fi sh stocks or changes in ocean temperature.
Conceptualising Ecosystem Benefits Across Land- and Seascapes 19
Drivers of change
Drivers are those processes, natural or human-in duced,
that can alter ecosystem function and thus alter the
delivery of ecosystem services. Human population
growth, for example, exerts pressure on natural systems
and leads to their conversion to urban, industrial or agri-
cul tural areas.
Coastal systems are naturally very dynamic, with unique
diurnal and periodical changes (i.e. tides, or fresh water
discharge), as well as infrequent extreme events such
as hurricanes or tsunamis which can naturally drive sig-
nifi cant change in coastal landscapes and ecosystems in
a very short time.
Drivers can be largely integral to the system, such as
presence of an alien species that can damage local
ecological relationships, or entirely exogenous, such as
climate change, and not amenable to manipulation by
local factors. It is essential to understand how these
exogenous drivers act on key ecological processes
within the system, and so affect the fl ow of ecosystem
services. Typically, multiple drivers act in complex syn-
ergy to produce ecosystem change, and most drivers
arise ultimately from human activities. The impact on
ecosystem services will vary with the magnitude, perio-
dicity and continuity of the driver. Habitat destruction,
change in land use and anthropogenic alteration of the
physical, biological and chemical setting are among the
most commonly reported agents affecting ecosystem
services in coastal areas.
The direct consequences of some drivers and their re-
lation to the provision/reduction of ecosystem services
are listed in Table 1. The multiple arrows display the
level of connectivity between the different drivers and
how the provision of ecosystem services depends not
only on the physical settings and enabling conditions but
also on the alterations from human activities and natural
disturbances.
Our choices at all levels – individual, community,
corporate and government – affect nature. And
they affect us.
– David Suzuki, Suzuki Foundation
20 Framing the flow
Table 1 – Drivers of change in coastal areas and their consequences on the provision of ecosystem services. The
diagram shows a simplifi ed description of drivers of change in coastal areas and their impacts on provision of ecosystem
services by mangroves, coral reefs, and seagrasses. The multiple color lines display the connectivity between the
different drivers and their impacts. Different widths represent different intensity of the impact. The circles of different
colors indicate the link between impacts, services provided and ecosystems.
Nutrient
enrichment
Consequences on the
natural environment
Habitat
destruction or
deforestation
Pollution
Species
replacement
and endemic
species at risk
Ecosystem
resilience
reduced
Alteration
of
communities
Pressure
on the
resources
Elimination
of
connectivity
Land
use
change
Need for
coastal
defences
Change on
physical
settings
Food
Provisioning
services
Regulating
services
Cultural
services
Supportive
services
Timber
Genetic
resources
Biochemical
resources
Coastal
protection
Buer from
oods and
storms
Pest and
disease control
Recreation
Aesthetic
and social
value
Soil and
substrata
formation
Photo-
synthesis
Nutrient
and water
cycling
Water
and air
quality
Economic activity
Alteration of
natural processes
Climate changeCoastal
development
Agriculture
Shipping
Unsustainable resources extraction
Aquaculture
Fishing
Tourism
Population growth
Coastal engineering
Political and economic incentives
Dredging
Substitution of natural ecosystems
Sea level rise
Change in magnitude and
frequency of natural
disturbances
Changes in hydrological
patterns
Temperature
Acidication
Terrestrial ooding
Marine originated disturbances
Drivers of change
Seagrasses
Mangroves
Coral reefs
All the three habitats combinedAll the three habitats combined
Seagrass and coral reefs
Mangroves and coral reefs
Provision of ecosystem services by ecosystem
Source: personal communication with Carmen
Lacambra; Workshop "Flow of Ecosystem
Services between Linked Habitats: from
Hilltops to the Deep Ocean", Cambridge, UK,
October 6-8, 2009; Agardi & Alder, 2005.
Conceptualising Ecosystem Benefits Across Land- and Seascapes 21
Climate change and marine ecosystem services
Empirical observations and climate models both indicate
that global climate and ocean conditions have been
changing over the last 100 years and will likely change
more rapidly in the future (IPCC, 2007). The oceans and
atmosphere are closely related, thus climate change
directly affects ocean conditions such as temperature
change, acidifi cation, low oxygen zones (‘dead zones’),
expansion of oxygen minimum zones, changes in ocean
current patterns, and reduction in sea-ice coverage
(Brewer & Peltzer, 2009). These changes affect the
biology and ecology of marine organisms as well as the
processes and functioning of marine ecosystems, such
as primary and secondary productivity, nutrient cycling
and trophic linkages, that are important to the various
goods and services provided to humans.
Biological responses to these ocean changes have been
observed in marine biomes (e.g. Perry et al., 2005; Dulvy
et al., 2008; Hiddink & Hofstede, 2008; Richardson, 2008;
Cheung et al., 2009a). For instance, nearly two-thirds
of exploited marine fi shes in the North Sea shifted in
mean latitude or depth, or both, over 25 years as sea
temperature increased (Perry et al., 2005; Dulvy et al.,
2008). These responses are suggested to result from
changes in physiology, distribution ranges and population
dynamics as ocean conditions change (Hiddink & Hof-
stede, 2008; Richardson, 2008; Cheung et al., 2009a).
Shifts in species distribution changes patterns of marine
biodiversity. Based on a modelling study of the potential
global shift in distribution ranges of 1,066 exploited mar-
ine fi sh and shellfi shes, Cheung et al. (2009a) found that
distributions of most species may shift towards the pole
at an average rate of around 40km per decade. This
projected distribution shift may result in a high rate of
species invasion into the high-latitude regions and local
extinctions across the tropics and in semi-enclosed seas
(Figure 5a and 5b).
Changes in ocean conditions will also result in changes in
primary productivity, population dynamics and the marine
food chain, thereby reducing ocean fi sh productivity.
Sarmiento et al. (2004) developed an empirical model
to predict ocean primary production using outputs
from global circulation models. They estimated that
global primary production may increase by 0.7 – 8.1%
by 2050, but with very large regional differences, such
as decreases in productivity in the North Pacifi c, the
Southern Ocean and around the Antarctic continent,
and increases in the North Atlantic region. It has been
observed that annual growth rates for the juveniles of
eight long-lived fi sh species in the southwest Pacifi c
increased in shallow waters and decreased in deep
waters where ocean warming and cooling occurred,
respectively (Thresher et al., 2007). Using historical
fi sheries catch, primary production and distributiondata
of 1,000 exploited fi sh and shellfi sh from around the
world, Cheung et al. (2008) developed an empirical model
that showed that maximum fi sheries catch poten tial of a
species is strongly dependent on primary production and
the distribution range of the species.
Combining the projected changes in distribution ranges
(Cheung et al., 2009a) and primary production (Sarmiento
et al., 2004) with the empirical model described in
Cheung et al. (2008), Cheung et al. (2009b) projected
future distribution of global maximum catch potential
by 2055. The results suggest that climate change may
cause large-scale redistribution of catch potential, with
a considerable reduction in catch potential in the tropics
(Figure 6).
Other changes in ocean conditions that may have direct
or indirect implications for ecosystem services include:
• change in the phenology (the timing of seasonal
cycles) of marine organisms (such as plankton) may
lead to important consequences for the way organ-
isms within an ecosystem interact and ultimately for
the structure of marine food-webs at all trophic levels.
For example, fi sh stocks may become more vulnerable
to overfi shing; and seabird populations may decline
(EEA, 2008);
• warming of the global ocean may result in the
symbiotic algae in corals dying or being expelled,
producing coral bleaching. This is predicted to have
devastating effects on coral reef-associated fi sh
species;
• with climate change, it is highly likely that the volume
of water in the sea may increase to such an extent
that many of the world’s corals will not be able to
adapt quickly enough to the increase in depth, again
with potentially serious consequences on coral reef-
associated species;
• climate change is modifying the chemistry of the
oceans, which can result in undesirable con sequen-
ces, e.g. the rapid increase in the number of areas
in the global ocean without oxygen, which are thus
unable to support living creatures. It is suggested
that oxygen minimum zones in the open ocean will
expand under climate change;
• climate change is acidifying the ocean, which in -
creases dissolved CO
2
and decreases ocean pH, car-
bonate ion concentration and calcium carbonate
mine ral saturation (Cooley & Doney, 2009; Secretariat
of the Convention on Biological Diversity, 2009).
22 Framing the flow
Figure 6 – Map of projected change in maximum catch potential under the SRES A1B scenario (redrawn from
Cheung et al., 2009b).
Figure 5 – Projected rate of species invasion (a) and local extinction (b) by year 2050 relative to 2000 under the
SRES A1B scenario. Rate of species invasion and location extinction are the number of species occurring in a new cell
or disappearing from a cell relative to their original species richness in year 2000 (redrawn from Cheung et al. 2009a).
Figure 5a
Figure 5b
Conceptualising Ecosystem Benefits Across Land- and Seascapes 23
Ecosystem resilience
In order to understand, measure or value ecosystem ser-
vices it is necessary to consider the resilience of ecosystems
to drivers of change and their capacity to provide services
despite the pressures acting upon the system.
A highly resilient ecosystem is capable of recovering more
rapidly from a disturbance than one that is less resilient.
Coastal ecosystems tend to have higher resilience when
several different species are performing the same role, es-
pecially if each member of a ‘functional group’ responds
differently to disturbance so that one species may be able
to take over from another. Species diversity, the biology of
the organisms present (e.g. their modes of reproduction and
dispersal) and habitat diversity all con tribute variously to
ecosystem resilience (Elmqvist et al., 2003).
Although ecosystems have always been subject to exo ge-
nous disturbance, often acting as a driver of adaptation and
speciation, the tipping point beyond which resilience fails is
diffi cult to determine. As drivers of change in coastal areas
intensify it becomes increasingly important to understand
and assess the components of ecosystem resilience in order
to maintain the delivery of ecosystem services.
Managing for sustainable ecosystem services
Improved understanding of ecosystem processes and
interactions should permit the fl ow of ecosystem services
to be tracked from source to benefi ciary across land and
seascapes, and so determine the boundary within which
management for sustainability should operate. If the
system under management does not include an area large
enough to ensure that essential ecosystem processes like
the recycling of nutrients, the fl ow of water and energy, and
reproduction and recruitment of juveniles into the system
are maintained, the sustainability of the system and its
services are at risk. While landscape ecology pioneered
the concept of understanding the physical relationships
between geographic elements of a system and managing
at scale, this was a precursor to the ecosystem approach
to management, which recognises the feedback loops
between human and ecological systems and the need to
optimise these to sustain benefi t fl ows from the system.
Traditional sectoral approaches, managing to maintain a
benefi t stream from one part of the system while ignoring
fundamental linkages to other parts of the system, will
often be inadequate when the full spectrum of ecosystem
services is considered.
Eco-regional planning is gaining international support as
an ecosystem-based approach for integrated planningand
conservation of coastal and marine resources at large re-
gional scale. This planning approach aims to identify the
con servation value and production potential over large
areas characterised by a shared set of ecological and bio-
geographic features. Understanding the linkages and com-
mon processes across the mosaic of habitats within the
larger ecoregion allows managers to prioritise measures to
safeguard key elements of the system and address threats
from human activities strategically. In this way important
ecosystem goods and services are preserved, and multiple
uses compatible with these values are designed and
sustained.
An example of ecoregion is the Mesoamerican Barrier Reef,
which spans the length of Belize and includes portions of
Mexico to the north and the coastal provinces of Guatemala
and Honduras to the south. Ecoregional planning focuses
on preserving the very high biological diversity in this
marine hot-spot and the ecosystem services it provides.
Ecosystem-based adaptation is a closely related ap proach.
In this paradigm, the ecosystem services produced by
healthy, well-integrated, natural communities are viewed
as essential to the resilience of human communities at-
tempting to cope with climate change and other forms
of global change. Protecting the integrity of ecological
processes from local human stressors helps to build the
natural resilience of these ecosystems and thereby to
sustain their production of services well into the future.
Table 2 lists some of the management measures and the
adaptation benefi ts they yield (The World Bank, 2009).
Table 2 – Table illustrating some of the management measures and the adaptation benefi ts they yield (The World
Bank, 2009).
Ecosystem-based Adaptation Creates Benefi ts for People
Restoring fragmented or degraded natural areas Secures biodiversity conservation and enhances critical
ecosystem services, such as water fl ow or fi sheries
provision
Protecting groundwater recharge zones or restoration of
fl oodplains
Secures water resources so that entire communities can
cope with drought
Connecting expanses of protected forests, grasslands,
reefs, or other habitats
Enables people and other species to move to better or
more viable habitats as the climate changes
24 Framing the flow
Figure 7 – Figure showing an integrated land-and seascape in which the fl ow of benefi ts from upstream woodlands
to downstream coastal areas is maintained across space and time. The upper watershed is protected to capture
rainwater and maintain high levels of biodiversity, which serve as refugia and sources of native plants and animals for
other parts of the landscape that may have been degraded. At lower elevations, secondary forest is maintained, allowing
for a balance between conservation and sustainable use, the recharging of aquifers and the continuous fl ow of clean
water. Further down the watershed, forests degraded through logging and encroachment of agriculture threaten to
interrupt ecosystem fl ows due to evaporation, siltation and nutrient run-off. These areas require active reforestation
to maintain hydrological conditions required downstream. In the coastal plain, wetlands are maintained to buffer
fl oodwaters, capture sediment and nutrients from waters draining into the nearshore environment, and serve as nursery
grounds for fi sheries. Along the exposed coast, coastal forests/mangroves are restored to prevent coastal erosion, shield
backwaters from storm surge and saltwater intrusion, and strip out remaining nutrients. This allows for the fl ow of clean,
clear, oligotrophic waters to support coral reefs offshore. The entire managed land/seascape interface is an active carbon
sink, capturing and storing CO
2
in biomass and in detritus and sediments, where it is sequestered indefi nitely.
1. Protected primary forest
2. Restored secondary forest
3. Degraded secondary forest
4. Agriculture
5. Wetland
6. Coastal forest buffer
7. Former pasture
Source: personal communication
with M.E. Hatziolos
Conceptualising Ecosystem Benefits Across Land- and Seascapes 25
These strategies suggest a new landscape paradigm
which actively manages key elements of the ecosystem,
balancing production with conservation, and harvesting
with restoration. Figure 7 depicts an integrated land- and
seascape in which the fl ow of benefi ts from upstream
woodlands to downstream coastal areas is maintained
across space and time.
Best management of tropical coastal seascapes must
address the connectivity of the constituent ecosystems,
including the adjacent terrestrial ecosystems, deman-
ding
coordination between institutions and integrated
catchment-coastal management, allowing for the pro-
tection of local ecosystem process as well as monitoring
and control of drivers outside the immediate target ma-
nagement system.
Key future research must include a better understanding
of how these linkages between ecosystem functions and
processes affect the delivery of ecosystem services. In
addition, we need to develop better estimates of the trade-
off entailed by different kinds of development, such as
tourism, housing or agriculture, and the resultant loss of
ecosystem services from previously healthy eco systems.
Increasing agricultural production to bring food security to
inland populations may reduce food security for coastal
populations because of increased sediment and nutrient
load and consequent decreased fi sheries production. New
economic and governance frameworks must be developed,
taking account of con nectivity across ecosystems to best
protect essential services and mini mise the potential for
confl ict.
A sound scientifi c understanding of the hydrological sys-
tem
– including how it functions and how it is affected
by human infl uence
– is important. Unraveling the web
of ecological interactions and processes that regulate
the ecosystem service within the target system and
understanding the nature of linkages (economic, social
and ecological) between this and adjacent systems across
the land-sea interface is essential to understanding key
drivers, putting a value on preserving production functions
and sustaining the quality of the ecosystem services of
interest.
Possible constraints include failure to account for the
effects of externalities such as climate change, which
may be outside the scope of local management entirely.
Current valuation methods are inadequate to quantify
many of the regulating and supporting services, or
the production functions which cannot be attributed
a market value although they may be fundamental to
provision of ecosystem goods and services. Hence they
are treated as free goods by society and discounted
in tradeoffs in the planning and development of the
ecosystem, or heavily degraded through pollution and
conversion. Thus wetlands, particularly marshlands and
mangroves, were treated as wastelands and converted
at rapid rates over the last 100 years for coastal
development and aquaculture. The repercussions of
this misguided development are now being felt in the
loss of vital natural coastal defense services, resulting
in severe flooding and saltwater intrusion as sea levels
rise and hurricane activity intensifies with climate
change.
26 Framing the flow
‘Quantifi ability’ of environmental services
Quantifying environmental services involves quantifying
both the processes that provide the material to be
consumed, the fl ow of that material, and the points in
space and time at which the fl ow is consumed or supports
humanity in some way and is thus recognised as a service.
In discussions on environmental services one should dis-
tinguish between those services that are provided by the
environment (environmental services per se) and those
that are a function of the ecosystem (ecosystem services).
In some cases services are provided by environments
irrespective of the ecosystem, for example, mountain zones
often have high rainfall because of orographic precipitation
(i.e. rising, cooling air is able to hold less water vapour)
which is independent of the ecosystem on the mountains
in question. The same ranges might also provide specifi c
ecosystem services, such as the contribution to water
resources made by tropical montane cloud forests (by ‘fog
stripping’ – the interception and capture of moisture by
foliage). This ecosystem service is a function of the cloud
forest ecosystem and is signifi cantly reduced when cloud
forest is converted to pasture, whereas simple elevation-
related rainfall is unaffected.
Ecosystem processes providing benefi ts in one zone
may have undesirable effects in another. For example,
forest planted upstream of drylands will increase water
withdrawal by evapotranspiration and potentially reduce
downstream water availability in those drylands.
Some services are more readily quantifi able than others.
Provisioning services that provide material goods (food,
fi bre and water) andrecreational value (a major part of cul-
tural services) are the best understood and valued, where-
as regulating services (maintenance of air, soil, water, and
eco system stability) are relatively poorly understood and
inadequately valued. Non-use cultural values are perhaps
the most important and least understood (Spurgeon,
2006). Most progress has been made to date in:
• quantifying the services that lead to agricultural and
fi sheries production;
• the provision of high quality drinking, irrigation or
industrial water;
• the sequestration and storage of carbon and regu-
lating functions such as coastal protection;
• on the valuation side, more progress has been made in
the valuation of services like recreation and aesthetic
values compared with the regulating services.
Representing fl ows of environmental services
between suppliers and consumers
Quantifying productivity and fl ows of water and carbon
has a long history in hydrological modelling and in
modelling terrestrial and oceanic ecosystem productivity.
Quantifying these as services is a more recent trend and
requires an understanding of their fl ow and consumption.
Flows of services can occur over space at variable scales,
between producing and consuming ecosystems (e.g.
environmental fl ows of water which maintain freshwater
habitats) or from nature to humanity and then between
human communities (a process often mediated by
markets and trading systems).
Quantifying such fl ows requires combined biophysical
and socio-economic analysis and modelling, performed at
a variety of spatial scales that incorporate the complexity
of production, fl ow, consumption, and trading relationships
in order to record the ultimate benefi ciaries of services.
These benefi ciaries may be on different continents to the
sites where the services were produced, as, for example,
in the case of agricultural commodities and hydro-power
generation. Quantifying environmental services fl ows also
requires an understanding of the value to individuals, mar-
kets and societies of the services provided and the cost of
not having access to them.
Spatial aspects of the supply side of ecosystem services
have been relatively well explored. A number of recent
studies have used Geographic Information Systems (GIS)
analysis to measure the ecological factors contributing to
the provision of services (Naidoo & Ricketts, 2006; Beier
et al., 2008; Nelson et al., 2009). These studies explore
how the provision of ecosystem services varies across
the landscape. However, far fewer studies have explicitly
identifi ed the demand side, or human benefi ciaries (Hein et
al., 2006) or mapped these benefi ciaries (Beier et al., 2008).
Yet the need for such mapping is increasingly recognised
(Naidoo et al., 2008). Supply and demand mapping are
complex, since ecosystem services provision and use often
occur across different spatial and temporal scales (Hein et
al., 2006) and some services can be ‘consumed’ without
loss and thus still available for further consumption. The
‘spatial mismatch’ or fl ow problem in ecosystem services
– cases where regions of service provision and use differ
– is well recognised (Ruhl et al., 2007; Tallis et al., 2008;
Tallis & Polasky, 2009). The ecosystem services research
community has so far concentrated on static mapping of
ecosystem service provision, and failed to quantify the
Chapter Two
Capturing and Quantifying the Flow of Ecosystem
Services
Capturing and Quantifying the Flow of Ecosystem Services 27
cross-scale fl ow of ecosystem services to different groups
of human benefi ciaries. Existing attempts at spatial fl ow
categorisation (Costanza et al., 2008) break ecosystem
services into coarse categories based on how their benefi ts
fl ow across landscapes to benefi ciaries, but in order to
adequately to address this spatial fl ow problem, methods
are needed to quantitatively assess spatio-temporal fl ow of
clearly identifi ed services to clearly identifi ed benefi ciaries.
There is much research to be done to better connect the
largely biophysical process knowledge available with
new knowledge on human consumption of environmental
services and ecosystem services and their fl ows through
markets and societies. Ultimately, the entire economic
system is fundamentally based on environmental services
and ecosystem services, yet these are typically regarded
as external to the production-consumption process. So
long as they remain externalities, markets will continue
to undervalue environmental services and ecosystem
services and use them unsustainably, it is therefore
essential to better understand the nature and fl ow pattern
of these services in order to develop policies able to
share their benefi ts more equitably and more sustainably.
Conventional approaches to quantifying the ge-
neration and fl ows of environmental services
(a) Marine services
A variety of approaches have been used to quantify services
delivered by marine ecosystems. Valuation exercises using
benefi ts-transfer approaches have applied estimates of
ecosystem service values for specifi c marine habitats to
extrapolate the global value of ecosystem services (e.g.
Costanza et al., 1997). Although simple, and important
for raising awareness of the importance of invariably
undervalued, non-market ecosystem services, this
ap proach can be misleading (Plummer, 2009) and is
not adequate to address the fl ow between areas of
provisioning and use. More sophisticated ‘production
function’ ap proaches have been used to ask how changes
in natural system functions lead to changes in the fl ows
and value of eco system services, but these have largely
focused on a subset of habitats (Barbier, 2003; Barbier, et
al., 2008) or single services (Batie & Wilson, 1978; Bell,
1989; Soderqvist et al., 2005). The most well-studied
service is the provisioning of food from fi sheries; food web
and ecosystem models have been used to understand
28 Framing the flow
how human activities affect complex interactions among
species and habitats and how these can in turn infl uence
catch of target species (e.g. Pauly et al., 2000; Christensen
& Walters, 2004; Fulton et al., 2004a, b). With the exception
of food from commercial fi sheries and aquaculture,
conventional approaches to quantifying fl ows of marine
services have focused on the modelling and measurement
of biophysical processes. While these ecosystem features
are essential to mapping fl ows across landscapes and
between habitats, they only account for the supply of
the service; without incorporating demand they cannot
quantify the service per se (Tallis & Polasky, 2009).
(b) Terrestrial water and carbon-based services
Before water quantity, quality and regulation came to be
considered as environmental services, hydrologists spoke
of water resources and of fl ood regulation and mitigation.
Hydrological assessment based on climate and river-fl ow
monitoring networks, coupled with empirical or physically-
based models, were and are used to assess water re-
sources and fl ood dynamics. A range of models exist for
this purpose at scales from global (WATERGAP 2, http://
www.usf.uni-kassel.de/watclim/pdf/watergap_model.
pdf) to local (SWAT, http://swatmodel.tamu.edu/). Many
of these models can, with some modifi cation, be applied
to study of the fl ow of hydrological ecosystem services.
A number of projects have used SWAT (e.g. http://www.
valuingthearc.org) and the CGIAR Challenge Programme
on Water and Food (http://gisweb.ciat.cgiar.org/wcp/pes_
workshop_nairobi.htm). The diffi culties in applying these
existing approaches to service valuation are that:
they were often not designed for application in the
types of environment where ecosystem services are
most important (for example, tropical mountains);
they are highly data demanding and these data are
often not available for less developed countries;
they focus on the hydrological processes rather than
the role of environments and ecosystems;
they often do not incorporate a valuation function
so their outputs are in hydrological rather than eco-
nomic units.
However, a new breed of hydrological models is focused
much more on understanding ecosystem services. These
include the InVEST hydrology module (http://invest.
ecoinformatics.org), FIESTA (http://www.ambiotek.com/
fi esta), the AGUAANDES policy support system (http://
www.policysupport.org/links/aguaandes) and Co$ting
Nature (see below).
Assessments of fl ow of environmental services asso-
ciated with carbon have focused on the measurement or
simulation of terrestrial carbon balances, including the
evaluation of sources and sinks, rather than the valuation
of carbon services per se. Most carbon models focus on
carbon cycle modelling and simulate carbon sequestration
and the growth of terrestrial carbon stocks. InVEST 1.0 has
a carbon storage and sequestration module which gives the
user the option to account for the value of carbon stored or
sequestered in the biomass and soils of ecosystems, either
via market prices or social values. No other ES-focused
dynamic simulation tool currently contains any carbon
component, though Co$ting Nature (see below) presents a
global valuation of carbon storage and sequestration.
New approaches to quantifying the generation
and fl ows of environmental services
Here we review some of the cutting-edge approaches
to quantifying the generation, consumption and fl ows of
environmental services.
(a) InVEST
The Natural Capital Project, a partnership of Stanford
University, The Nature Conservancy and World Wildlife
Fund, has embarked on a two-year program to develop
a suite of spatially explicit, process based models for
mapping and valuing services provided by coastal and
ocean ecosystems (Ruckelshaus & Guerry, 2009). The
marine InVEST (Integrated Valuation of Ecosystem
Services and Trade-offs) approach, derived from terrestrial
InVEST, addresses many of the limitations of previous
methodologies. Models consist of a biophysical step,
where supply of the service is quantifi ed, a use step where
demand for the service is quantifi ed, and an economic step
for valuation in monetary terms. Suffi ciently general to be
transferable, marine InVEST assesses a suite of ecosystem
services and can be used with diverse habitats, policy
issues, stakeholders, data limitations, and scales.
Managers and policy makers often lack the tools to
integrate across sectors and issues, and to elucidate
potential trade-offs among ecosystem services. Models
for a variety of marine ecosystem services are currently
in development within the marine InVEST tool, including:
food from commercial fi sheries and aquaculture; pro-
tection from coastal erosion and inundation by marine
habitats; wave energy generation; and recreation (e.g.
whale watching, recreational fi shing and scuba diving).
By mapping and valuing a suite of services, the marine
InVEST approach can elucidate the relationships between
services and help to identify management options that
minimise trade-offs.
In order to inform decision making effectively, marine
InVEST is built to be relevant to the needs and questions
confronting managers and policy makers. The models
map and value ecosystem services under current and
future management, and climate-change scenarios.
Marine InVEST is best employed within a stakeholder-
engagement process that identifi es alternative manage-
ment scenarios, such as a change in the number of aqua-
culture farms or wave energy conversion facilities, the
siting of marine protected areas, harvest regulations, and
(i)
(ii)
(iii)
(iv)
Capturing and Quantifying the Flow of Ecosystem Services 29
habitat restoration scenarios (see Figure 8). Marine InVEST
models how alternative management scenarios, coupled
with climate change, are likely to infl uence ecosystem
structure and function, and then how such changes might
affect the fl ows of marine ecosystem services.
Marine InVEST is based on production functions that
defi ne how the biophysical processes characteristic of
an ecosystem lead to fl ows of ecosystem services (i.e.
adding demand for and valuation of those processes).
Much previous research has been focused on the ability
of habitats such as mangroves, wetlands and corals,
to attenuate storm surge and wave action. However,
this focus on the supply side of coastal protection
services does not account for the use of this service.
For example, are there people and structures that
would be affected by coastal erosion or fl ooding? The
marine InVEST models for coastal protection address
this problem by provid ing biophysical outputs (such as
reduction in wave height per area of marsh), ecosystem
service outputs (such as reduction in the area of property
Figure 8 – A hypothetical illustration of Marine InVEST model inputs and outputs. Inputs include spatially explicit
information about current conditions and potential future uses of the marine and coastal environment. Outputs
include modeled changes in a wide range of ecosystem services based on changes in inputs to production functions.
Qualitative outputs are shown here for simplicity; quantitative outputs (in biophysical and economic terms) will be output by
the models. Question marks indicate uncertainty in directional change. Spiral symbols at the base of dunes represent wave
action at feeder bluffs resulting in beach nourishment. The ecosystem service of coastal protection is predicted to increase
in Scenario 2 because removal of shoreline armoring in conjunction with natural beach nourishment and restoration of
biogenic habitat increases this ecosystem service that was previously provided by an anthropogenic hard structure.
eroded or inundated per unit area of marsh) and outputs
in economic (such as the avoided damage to property
or structures per area of marsh) and other valuation
terms (such as avoided displacement of people). The
models are spatially explicit in order to account for
landscape heterogeneity (Tallis & Polasky, 2009), such
as variation in the area and density of biogenic habitat,
or hydrodynamic conditions that could infl uence the
delivery of the service (Moller, 2006; Koch et al.,
2009), and the location, type and intensity of use. Like
the terrestrial InVEST tool, all marine InVEST models
produce output in the form of maps and data tables
(Nelson et al., 2009).
(b) Quantifying ecosystem service fl ows in ARIES
ARIES (ARtifi cial Intelligence for Ecosystem Services) is a
new web-based tool for ecosystem services assessment,
planning and valuation, developed by the University of
Vermont, Conservation International, Earth Economics,
and UNEP-WCMC (Villa et al., 2009).
30 Framing the flow
By creating ad-hoc, probabilistic models of both provision
and use of ecosystem services in a region of interest, and
mapping the actual physical fl ows of those benefi ts to
their benefi ciaries, ARIES helps discover, understand and
quantify environmental assets, and what factors infl uence
their value according to explicit needs and priorities.
Analysis of multiple ecosystem services can enable
system users to overlay services, identifying areas that
provide multiple ‘stacked’ or ‘co-benefi t’ services, to
compare tradeoffs between services, and consider the
policy options that affect their provision.
The primary objective of the tool is the valuation of the
fl ow of ecosystem services between linked habitats. The
outputs of ARIES have numerous practical and novel
uses for conservation and economic development plan-
ning.Notably, they can show which regions are critical to
maintaining the supply and fl ows of particular benefi ts for
specifi c benefi ciary groups. By prioritising conservation and
restoration activities around provision and consumption of
particular services, benefi t fl ows may be maintained or
increased. Similarly, focusing development or extractive
resource use outside these regions can prevent decline
of benefi t fl ows. Scenario analysis completed in ARIES
can high light areas that need to be preserved in order
to maintain the interconnections between ecosystems,
aiming to en sure their full functionality. By identifying
parties that benefi t from or degrade benefi t fl ows, these
maps can also support implementation of Payments for
Ecosystem Services (PES) programs (with benefi ciaries or
polluters paying according to use). Finally, specifi c maps
for an ecosystem or benefi ciary group of interest can also
be generated. Such maps can show either (a) the parts of
the landscape from which a specifi c benefi ciary’s benefi ts
are derived, or (b) the benefi ciary groups receiving benefi ts
from a specifi c ecosystem region of interest.
Marine and coastal ecosystems provide many goods and
services of value to humans, but the behaviour of these
systems is complex and can change rapidly. Linkages
and tradeoffs between services require integrated
planning and management in order for service levels to be
preserved. Ecosystem services for probable consideration
in ARIES include fl ood protection of critical coastal habitat,
sedimentation, and the provision of nursery habitats for
valuable fi sh populations.
The ARIES technology (Villa et al., 2009) couples pro-
babilistic models of ecosystem service provision, use,
and sink with SPAN models to quantitatively assess eco-
system service fl ows (Figure 9).
Johnson et al. (in review) introduce a novel Service Path
Attribution Network (SPAN) algorithm that models the
fl ow of matter, energy or information from a provisioning
region to spatially identifi ed recipients, while determining
the sink dynamics that occur along the fl ow path. SPANs
are ideal for modelling ecosystem services, because spa-
tial fl ows for each service can be based on uniquely defi ned
fl ow characteristics between regions of provision and use.
The benefi t received may accrue from receipt of a quantity
at the benefi ciary’s location (as in the receipt of ecosystem
goods, aesthetic views, or proximity to open space), or
from the absorption of a negative quantity en route to the
benefi ciary (as in the mitigation of fl ood waters, uptake
of nutrients, or deposition of sediment). The ARIES tech-
nology (Villa et al., 2009) couples probabilistic models
of ecosystem service provision, use and sinks with SPAN
models to quantitatively assess ecosystem service fl ows.
In order to use SPANs, it is necessary to quantify the initial
location of benefi t carriers and the spatial location of their
benefi ciaries.
(c) Co$ting Nature
Co$ting Nature (costing nature) is a collaboration between
King’s College London and UNEP-WCMC and comprises
the Co$ting Nature global analysis and the Co$ting Nature
PSS (Policy Support System).
The global analysis uses a web-based series of interactive
maps that, for particular systems (e.g. protected areas,
cloud forests, forests in general, or ecoregions), defi nes
their contribution on a site by site basis to the global
Figure 9 – Diagram illustrating the approach used by
ARIES in order to quantifying ecosystem service fl ows
of matter, energy, or information from a provisioning
region to spatially identifi ed recipients. Each modelled
provisioning region produces a homogeneous quantity of a
benefi t supplier. Estimation of the fl ow to use regions often
requires a transport- or agent-based model, so to assess
fl ood regulation as an ecosystem service, a hydrologic model
can be used to estimate runoff based on the initial location
of runoff or snowmelt. Arrows in the provision regions in-
dicate spatial fl ows. Connections between provisioning and
use regions show the relative dependence on benefi ts to a
benefi ciary of different parts of the landscape. In the above
example, benefi ciaries are most strongly dependent on ser-
vices provided by inshore marine systems.
Capturing and Quantifying the Flow of Ecosystem Services 31
reservoir of a particular service and its realisable value
(based on fl ows to consumers of that service). The services
so far defi ned are water (quantity and quality) and carbon.
This analysis aids visualisation and understanding of both
the magnitude and geographical distribution of services at
a global level and some estimates of their economic value.
For a chosen site, the Co$ting Nature PSS allows the
quantifi cation of service provision but also fosters an
understanding of the impact of scenarios for changes
in land use, climate and service consumption on service
supply and distribution downstream in the fl ow network.
It is designed to help test policies for land use and other
interventions by simulating their impact on the distribution
of service provision. It has a core of biophysical models
and is intended to support those working to understand
fl ows of ecosystem service (without necessarily valuing
those fl ows in economic terms). It has both a scientifi c and
a policy support interface that operates the same models
but provide different levels of output detail. Services
examined to date include water purifi cation and carbon
sequestration.
Water: dilution and purifi cation services – protected
areas and natural ecosystems can be assumed to
provide higher quality water than agricultural, in-
dustrial and urban areas that are subject to human
infl uence (pollution, pesticide, herbicide, and fertiliser
application). Thus, mapping the global protected areas
system and their relation to rivers can yield an indi cation
of where protected areas provide a service and how
many people benefi t from it. Moreover, since people
will pay for cleaner water (or else have to pay for water
treatment to achieve the same), the economic value
of this water can be established if the downstream
consuming populations are known (Figure 10).
(i)
32 Framing the flow
Carbon: storage and sequestration. By taking existing
maps of global carbon storage (Gibbs et al., 2007)
and combining them with new maps for global
carbon sequestration based on 10-year time series of
decadal satellite data, we can calculate the carbon
storage and carbon sequestration by ecosystem,
protected area (Figure 11) or ecoregion, and thereby
understand where human emissions are being offset
by nature and estimate the economic value of these
offsets.
Elements of the Co$ting Nature policy support system
focused on water in the Andes are accessible at http://
www.policysupport.org/costingnature/pss. The model
currently allows the simulation of complex hydrological
processes and their outcomes at 1km or 1ha scale using
a GIS database and models defi ning the hydrological
provisioning services, their downstream fl ow networks
and their consumption at dams, cities and by agriculture.
The intention is to incorporate agricultural production
and carbon sequestration services to this system in the
near future.
Conclusions: Providing the data to internalise
nature’s role in the economic system
Modelling environmental service provision across multiple
services is in its infancy. All of the tools discussed are at
early stages of development and release. At this stage
it is important that a number of approaches continue to
coexist and practitioners communicate and learn from
each other. No one approach is the best approach under
all circumstances.
In these early approaches the different services are often
modelled concurrently but not well connected in process
terms, making it diffi cult to analyse, for example, the
impact of terrestrial services on the marine services,
or the trade-offs between carbon and water services of
forests. All of the available tools have signifi cant data
requirements and, whilst they are generally designed to
Figure 10 –Realisable water value of protected areas (millions of US$/park/yr). Note that realisable water value is
the direct value of water for human use – there are intrinsic values of water that are not accounted for here – for example,
environmental fl ows that sustain other ecosystem functions. Australia excluded. See http://www.policysupport.org/
costingnature for the global analysis.
(ii)
Capturing and Quantifying the Flow of Ecosystem Services 33
be parsimonious and make use of readily available data,
there can still be signifi cant barriers to their effective use
in a particular environment.
As with all modelling efforts, the level of uncertainty
associated with outputs is variable and signifi cant, and
this can impede effective communication with decision-
makers. ARIES is perhaps best developed in this regard
since its use of Bayesian techniques allows quantifi cation
of some elements of uncertainty. Of course, a model
is no more than a hypothesis of how the systems work
in reality, and output quality is limited by the quality of
input data. The challenge in understanding and managing
ecosystem service fl ows will be to provide a suite of tools
that:
communicate with each other rather than compete;
use the best available data;
are driven by end users and can be applied with the
levels of capacity that exist in the decision making
contexts for environmental service assess ment;
act as a common information platform, accessible to
all and around which negotiation for more sustainable
use of environmental services can be facilitated.
Figure 11 – Carbon sequestration of the global protected areas system (millions of tonnes C per yr). Areas of low
sequestration are generally ice covered, marine, desert or at high latitudes.
(i)
(ii)
(iii)
(iv)
34 Framing the flow
What is economic valuation?
Economics is a science of trade-offs. Economic valuation
facilitates the translation of ecosystem services into
comparable human values and offers a way to compare
the diverse benefits and costs associated with eco-
systems by attempting to measure them in terms of a
common denominator. The ability to compare very unlike
things with a common metric is an activity we undertake
implicitly every day: shall we go out to dinner or give
money to charity? Shall we invest in health care or in
foreign wars? Through the use of markets and market-
like arrangements, economic valuation facilitates the
comparison of valuable stocks and fl ows of ecosystem
services. Economic valuation of ecosystem services,
much like benefi t-cost analysis, does not lead directly
to policy decisions, as it provides only a partial view
of the context within which decisions must be made.
Frequently, however, economic valuation of ecosystem
services provides the only non-zero estimate of the value
of biodiversity against which goods and services whose
total value is well refl ected by the marketplace can be
reasonably compared.
Why undertake economic valuation?
Economic valuation of ecosystem services can help us
to understand the interconnections among people and
ecosystems across space and over time. Economic valua-
tion can raise awareness of the environment, improve
resource allocation decisions for scarce and valuable re-
sources, particularly when the market fails to do so, and
provide the means to trace the distributional implications
of decisions to stakeholders.
More specifi cally, economic valuation can raise awareness
by revealing the willingness to pay of individuals and
society for environmental services, estimating human
welfare losses due to environmental degradation and
the true costs and benefi ts of environmental protection.
Economic valuation can improve land use decisions, inform
pricing for natural resource-based experiences, identify
avenues for fi scal reform, and facilitate the transfer of
fi nancial resources from those who benefi t from eco-
system services to those who manage them.
What are the general categories of economic
value?
Pagiola et al. (2004) summarise the common moti-
vations and approaches to ecosystem service valuation
(Figure 12). The main framework used is a Total
Chapter Three
Valuing Ecosystem Services of Coastal Habitats
Economic Value (TEV) approach, based on fi ve different
types of economic value organised in two general
categories. The two general categories of economic
value are use, or active value, and nonuse, or passive
value. Use value is further divided into consumptive use
and non-consumptive use value, while nonuse value is
divided into existence and bequest value. Lastly, option
value has been considered a nonuse value, but is now
increasingly categorised as a use value.
Use value implies that individuals derive direct benefi t
from being in the presence or vicinity of the natural
resource. Consumptive use value is when the resource
is, through its use, consumed or used up such that
other people or economic activities do not have an
opportunity to enjoy the resource. Non-consumptive
use value implies that users do not consume, or use up,
the resource in the process of enjoying it. As such, non-
consumptive uses of resources do not preempt current
or future non-consumptive uses or future consumptive
uses of the resource. Indirect use values are derived
from ecosystem services that provide benefi ts outside
the ecosystem itself (i.e. the storm-protection function
of mangrove forests).
Nonuse value implies that people derive benefi t from
the natural environment without having direct contact
with it; the value is independent of use of the resource,
but dependent on its quality and/or quantity. Existence
value is manifest when individuals experience benefi ts
from aspects of the natural environment that they do
not reasonably expect to experience personally. Bequest
value is the value that individuals derive from providing
desirable features of the natural environment to future
generations. Option value has to do with choosing not to
use a resource today, while retaining the option to use it in
the future. As a result, it can be considered a nonuse value
in the current period with an option for (consumptive or
non-consumptive) use value in the future.
What are the common economic valuation
methods?
Economists employ a number of techniques to estimate
social and individual values for natural resources. These
tech niques include direct and indirect market-based
methods and non-market valuation methods. Direct
market price analysis is an appropriate technique to assess
the use value of natural resources. It is best used when
the good or service in question is commonly traded in the
Valuing Ecosystem Services of Coastal Habitats 35
Total Economic Value
Use values Non-use values
Direct use values
• Consumptive
• Non-consumptive
Indirect
use values
Option
values
Existence
values
Bequest
values
Figure 12 – Category of the total economic value (TEV). Source: modifi ed from Beaumont & Tinch, 2003.
Not everything that can be counted
counts, and not everything that counts
can be counted
– Albert Einstein
36 Framing the flow
open market and can be considered the total value of the
good, and if there are no important external effects in its
production or consumption. That is, the price is generated
through purchase behavior and price equals value.
Indirect market price analysis also allows the analyst
to value use values, but typically the value in question
is embedded in the market price of another good or a
closely related good traded in the market. It can be that
markets are malformed due to the features of the goods
and services themselves or due to the institutions evolved
for their management.
The two most common indirect market valuation tech-
niques are the travel cost method (TCM) and the hedonic
price method (HPM). The TCM is a commonly employed
analytical tool to facilitate understanding of the demand
for tourism services. The HPM is a commonly employed
analytical tool used to understand the housing market,
but it has applications to all products with multiple sepa-
rable and valuable features.
For many issues concerning stewardship of natural envi-
ron ment there are few market signals of any kind to
provide guidance as to its relative social value. This is
particularly the case with expressions of nonuse value.
However, without attempting to derive a usable economic
value, it is tempting for policy makers to ignore the
social worth of the environment or to assume that it is
essentially zero. Nothing could be further from the truth,
as most often these non-market valuation techniques are
criticised for the uncertainty over the value estimated
and for at tempting to place a value on the priceless, the
infi nitely valued. In the market-based methods, people
reveal their preferences for environmental goods and
services through their purchase decisions. With non-
market techniques, such as contingent valuation (CV)
and contingent behavior (CB), consumers are enticed,
through choices in a survey, to state their preferences
via a hypothetical, or contingent, market or ‘choice
experiment’.
Another methodology employed is benefi t transfer that uses
results obtained in one context in a different context and is
applied when suitable comparison studies are available.
What are the general considerations and
challenges when conducting an economic
valuation?
Economic valuation works best when:
• the preferences of all those who are affected by the
valuation decision are taken under full consideration;
• important changes in ecosystem services across al-
ternatives are fully accounted for;
• those who are asked to express their preferences are
able to understand the alternatives and express their
preferences;
• policy alternatives are available to align incentives
such that those who are affected by changes in the
fl ows of ecosystem services can communicate with
those who are charged with their stewardship.
All four of these criteria raise a variety of important
challenges, prominent among which is locating ac curate
and reliable data for nonmarket values on a par with that
which the market provides for marketed products.
In many cases, rich or important natural resources are
found where poor people live. When markets and mar-
ket-like mechanisms are used to derive social values, poor
people have less ability to refl ect their values in absolute
terms, having fewer ‘votes’ in a market-based resource
allocation system. This typically contributes to problems
with concentrated costs among a few and diffuses benefi ts
among many and inequitable decision-making.
Finally, equating use and nonuse values is more diffi cult
than it might appear. Most studies focus on the direct
use values of marketed products, for which data
can be obtained more easily. Nonmarket ecosystem
services are rarely or unreliably valued, due to poor
data on biophysical relationships. Most analyses are
site-specifi c and focus on a single good or service at
one point in time, and assume fi xed prices. The extent
that multiple ecosystem service values derived from a
single site should be added together (‘stackability’) is a
matter of signifi cant debate. Non-use values are diffi cult
to defi ne, tricky to estimate and even harder to capture,
due to free-riding, lack of accepted transfer mechanisms
and variation in people’s ability to understand what is
being valued. As a result, actually valuing biodiversity
(e.g. via species richness or genetic diversity) presents a
formidable challenge.
Approaches to valuation: toward a third
generation economics based approach
The approach based on Total Economic Value (TEV), pre-
viously described, can be regarded as a fi rst generation of
economics based approaches. Examples applied to coral
reefs are cited by Cesar (2002) and Ahmed et al., (2004),
highlighting that the benefi ts and values from this eco-
system come not only from direct uses, such as tourism
and fi sheries, but also from indirect uses (Spurgeon, 2006).
In a more integrated ‘second generation’ approach, the
economic valuation attempts to focus on other aspects
(Spurgeon, 2006):
• economic impact (to assess the contribution to local,
regional and national economies);
• fi nancial aspects (to determine the sustainability of
enterprises and organisations);
• socio-economic analysis;
• other indicators (e.g biodiversity).
Valuing Ecosystem Services of Coastal Habitats 37
A ‘third-generation’ economic based approach has been
proposed by Spurgeon (2006) with the intention of:
• incorporating modern business management prin ciples
and approaches to enhance ecosystem benefi ts to
society, reduce management costs and help reach
con servation objectives. These potentially could in-
clude marketing (market segmentation, targeting
and positioning), fi nancial and management accoun-
ting (business plans, budget/profi t and loss), opera tion
management (e.g. performance objectives), organ-
isational behavior (group dynamics), and stra tegy (e.g.
scenario planning);
• gaining a better understanding of what values mean
and how to estimate most of them. This can allow to
carry out more accurate and complete valuations and
help improve decision-making that affects tropical
coastal ecosystems;
• involving appropriate use of innovation, technology
and collaboration;
• accounting more for spirituality, quality of life and
inter-generational equity.
Economic values of services in coastal
ecosystems
A substantial positive economic value can be attached
to many of the marketed and non-marketed services
provided by coastal ecosystems (Agardy et al., 2005).
These values are a combination of use and nonuse values.
However, there are also other types of ecosystem service
Table 3 – Approaches to valuation of ecosystem services. Source: Pagiola et al., 2004.
values that these coastal ecosystems provide. Many
people derive great pleasure in the fact that the colorful
coral reefs exist in the sea (existence value); perhaps
they would like the ecosystems to stay intact for the
enjoyment and benefi t of their children (bequest value).
All of these values combine to form the fi nal ecosystem
service value of an ecosystem.
Coral reefs provide a wide range of services to around
more than half a million people (Agardy and Alder,
2005). The benefi ts from these ecosystem services
are signifi cant, estimated to be around US$172 billion
annually (Martínez et al., 2007). The values change
regionally, according principally to who benefi ts directly
and the type and size of the coral reef system. The
estimated annual benefi t from coral reefs is about
US$129,200/ha. Much of the economic values of coral
reefs are generated from nature-based and dive tourism,
with the net benefi ts estimated at nearly US$79,099/
ha. Mangroves are estimated to be worth on average
US$4,290/ha, while estuaries, lagoons and seagrasses
are estimated to provide benefi ts to an average value of
US$73,900/ha (TEEB, 2009).
Coastal systems generate a variety of seafood products
such as fi sh, mussels, crustaceans, sea cucumbers, and
seaweeds. Many commercially important marine species,
like salmon, shad, grouper, snapper, bluefi sh, striped bass,
and invertebrates (such as shrimp, lobster, crabs, oysters,
clams, mussels), use coastal nursery habitats. Capture
fi sheries in coastal waters alone account for US$34 billion
in yields annually (MA, 2005).
Approach Why do we do it? How do we do it?
Determining the total value of the
current fl ow of benefi ts from an
ecosystem
To understand the contribution that
ecosystems make to society
Identify all mutually compatible services
provided; measure the quantity of each
service provided; multiply by the value of
each service
Determining the net benefi ts of an
intervention that alters ecosystem
conditions
To assess whether the intervention is
economically worthwhile
Measure how the quantity of each
service would change as a result of the
intervention, as compared to their quan-
tity without the intervention; multiply by
the marginal value of each service
Examining how the costs and
benefi ts of an ecosystem (or an in-
tervention) are distributed
To identify winners and losers, for
ethical and practical reasons
Identify relevant stakeholder groups; de-
termine which specifi c services they use
and the value of those services to that
group (or changes in values resulting from
an intervention)
Identifying potential financing
sources for conservation
To help make ecosystem conser-
vation fi nancially self-sustaining
Identify groups that receive large benefi t
fl ows, from which funds could be ex-
tracted using various mechanisms
38 Framing the flow
Figure 13 – Estimated annual ecosystem benefi ts for coastal ecosystems.
Valuing Ecosystem Services of Coastal Habitats 39
Mangroves are permanent or temporary habitats for
many aquatic animals, and provide hatching sites and
nursery grounds for many marine fi shes. The annual
market value of seafood from mangroves is estimated at
US$750-16,750 per hectare (MA, 2005).
Valuing ecosystem services provision, use and
fl ow
Combining information on the biophysical mechanisms of
ecosystem services provision together with the economic
implication of the use of ecosystem services could allow
better management and governance
(MA, 2005).
The quantitative understanding of ecosystem service pro-
vision and use has not suffi ciently evolved to allow the
productive use of spatial mapping, economic valuation
and related tools to inform accurate decision and policy
making (Boyd & Banzhaf, 2007; Wallace, 2007; Turner &
Fisher, 2008).
A comprehensive approach has to take into account the
complex, multi-scale dynamics of ecosystem services
provision, use and fl ow in order to inform decisions and
allow for scenario analysis in a quantitative and spatially
explicit fashion.
The estimation of stability and time required to return to
equilibrium after disturbance are in most cases based on
linear methods (CIESM, 2008), but ecological-economic
systems typically react in a non-linear manner. This is
problematic for analysis. In non-linear systems, small per-
turbations can become magnifi ed and lead to qualitatively
unexpected behaviours at macroscopic levels. Monetary
analysis may be misleading if we do not know how close a
system is to a threshold, or tipping point (TEEB, 2009), but
we are still far from having developed a system to anticipate
shifts with any precision (Biggs et al., 2009).
There are many site-specifi c studies of marine ecosystem
services, looking at issues of subsistence fi shing, shoreline
protection, tourism, and recreation. It remains diffi cult
to combine the values of different sectors, and there are
issues around adding up the different ecosystem service
values (‘stackability’) at a single site or type of site.
However, in order to give policy makers some information
so that they can begin to include the values of ecosystem
services into their decision making, this strategy of creat-
ing aggregated bodies of information from multiple sites
is being attempted by a range of researchers, across a
range of ecosystem types.
The MA classifi cation of ecosystem services communi-
cates the importance of nature in satisfying different
domains of human well-being, but, as has recently been
highlighted, this classifi cation does not lend itself well
to economic decision-making (Boyd & Banzhaf, 2007;
Wallace, 2007). The main issue is that benefi ts and human
benefi ciaries are not explicitly linked. The fl ow of benefi ts
is the only quan tity that relates supply and demand
and therefore is a natural candidate for a quantitative
statement of value. Ecosystem valuation, environmen-
tal accounting (Boyd & Banzhaf, 2007), development
choices and sup por ting payments for ecosystem services
programs may be better supported by improving the
defi nition of these benefi ts and benefi ciaries.
Spatial mapping, combined with a defi nition of benefi ts
and benefi ciaries, can be a useful tool to support the
valuation process and identify regions more likely to
provide higher or lower levels of value (Boyd & Wainger,
2003). The ecosystem services fl ow information can be
used to build a transfer function to translate previously
assessed economic values for specifi c benefi ts into es-
timated valuation portfolios when that is required by
the users (Villa et al., 2009). This approach has been
supported by international organisations and agencies in
order to overcome the lack of value estimates at target
sites, particularly in developing countries, due to time and
budget constraints that limit original study (Desvouges et
al., 1998; Shrestha and Loomis, 2001).
The primary goal is to provide policy makers with a
measured quantitative value, more easily weighed against
competing concerns, in order to enable better decision
making in natural resource management. Among the mul-
titude of factors to be addressed are: the evidence of the
non-linearity in ecosystem services; the large dimension
of the ecosystems delivering services; the future use of
the resources; the fact that the value varies according to
scale; the opportunity to create a hierarchy of options;
the principle of equity among benefi ciaries; the fact that
the values can change quickly; the diffi culty of evaluating
some ecosystem services (temporal and seasonal factors);
the need to adapt analytic and presentational tools to
the specifi c needs of policy makers; and the scope for
developing ‘with or without’ scenarios.
40 Framing the flow
Application for Business and Industry 41
Impact and dependence on Ecosystem Service
Flow for Industry
Businesses have many reasons for ensuring that sources
of ecosystem services are maintained over time. Most
importantly, businesses are often major benefi ciaries of
ecosystem services, in that they depend on natural assets
such as water (e.g. bottled water industry or aquaculture),
pollinators (e.g. food industry), soil erosion control (e.g.
hydroelectric plants), or scenic beauty (e.g. tourism
industry). Maintaining access to these resources and
guaranteeing their sustainable use enables businesses to
operate at a desirable level of productivity, keeping costs
of inputs low, avoiding operating in scarcity conditions
and reducing risks to the supply chain.
Terrestrial, coastal and marine ecosystems are connec ted
by hydrology, geomorphology and movement of species,
nutrients and minerals. They provide an array of interlinked
services that are necessary for a wide range of industry
operations but may be directly impacted by them. Because
such services do not occur in isolation, ecosystem impacts
can be far reaching, and lead to tradeoffs among services.
The challenge for industry is to determine where their
supply chain relies on ecosystem services and where and
how their operations may impact ecosystems and the fl ow
of services. Ultimately industry will benefi t from taking
an integrated approach to the management of ecosystem
services by incorporating these services into environmental
management systems.
Changes being made to ecosystems are resulting in an
increased likelihood of potentially serious and abrupt
changes in physical and biological systems, such as
disease, decreased fresh water availability, spread of
low oxygen (‘dead’) zones in water bodies, and fi shery
collapse. Capabilities for predicting such abrupt changes
are improving, but for most ecosystems and their services,
science cannot yet forecast thresholds beyond which
non linear changes will be encountered (MA, 2005; TEEB,
2009).
The value of these interconnected ecosystem services is
generally not refl ected in markets (TEEB, 2009), but their
degradation is likely to impact industry through increased
risk, higher operational costs (where the supply chain
depends on services or where impact must be mitigated),
stricter regulations, and lost opportunities.
Although Environmental Impact Assessments (EIAs) are
becom ing increasingly aware of the potentially negative im-
pacts of land management spreading between ecosystems,
not enough importance is attached to the environmental
opportunities that can arise from interconnected systems
exchanging energy, matter and information in ways that
directly benefi t human well-being. For example, nutrient-
rich sediments that accumulate in rivers play an important
role in supporting downstream wetland communities.
Historically, there has been a limited conceptual framework
for business to view ecosystem services holistically as
they fl ow across and between ecosystems, from mountain
tops to the ocean. Benefi ts of maintaining the fl ow of
ecosystem services derive not only from reducing risk and
securing supply of those services, but also in restoring the
fl ow of services between and among ecosystems.
How the concept of the fl ow can enhance
business competitiveness and strategy
Recognising the dynamic links between terrestrial,
coastal and marine ecosystems, and how ecosystem
services fl ow across these systems could help busi-
nesses improve their environmental performance, reduce
risks and costs, and gain larger public support. Adopting
the concept of ecosystem service fl ow as part of business
planning involves acknowledging the spatial and temporal
coupling between areas where services are generated
and those where they are being used. It also involves
understanding the mechanisms through which ecosystem
services fl ow from points of source to points of usage.
Sound information on the three components of ecosystem
service – fl ows, source and use – is necessary to inform
business decision-making and enable ecosystem health to
be maintained.
Businesses might also be interested in maintaining
ecosystem services that do not directly impact business
operations but are important to local communities and
specifi c benefi ciaries. In this case, adopting the concept
of ecosystem service fl ows entails that businesses
evaluate the potential impacts of their activities over
the entire array of benefi ciaries that depend on a given
ecosystem service, whether in the immediate vicinity
or further along the terrestrial-marine gradient. This
practice of managing direct and indirect impacts would
have the advantage of reducing confl ict with interest
Chapter Four
Application for Industry and Business
42 Framing the flow
groups, increasing com munity support and extending
‘social license’ to operate.
In this context, effective risk management requires main-
taining critical pathways of ecosystem services ac ross the
terrestrial-marine gradient, and understanding how these
pathways can change as a response to inter ventions on the
landscape. Acknowledging the spatial fl ows of ecosystem
services across the landscape also provides businesses
with the opportunity to identify miti gation options and ways
to positively infl uence existing pathways to reach more
benefi ciaries, and perhaps marginalised communities.
Ultimately, environmental performance that is basedon
maintaining the sources of ecosystem services, recog-
nising the existence of multiple benefi ciaries and ac-
cepting the need to protect critical ecosystem service
pathways can result in lower costs of operation, regu-
latory compliance and confl ict.
How the concept of the fl ow can support
environmental performance expectations
Businesses are increasingly being asked by informed
consumers to improve their environmental and social
performance by reducing emissions, increasing effi ciency
in resources use and maintaining fair relationships with
workers and local communities. Public concern for
sustainability is a stronger driver of technological in-
novation and sustainability agendas than governmental
regulation. In many cases, businesses adopt sustainability
measures on a voluntary basis, exceeding regulatory
environmental performance standards. Within the context
of a dynamic and integrated view of ecosystem services
along the terrestrial-marine gradient, businesses have
the opportunity to demonstrate improved performance
by maintaining ecosystem service sources, negotiating
with ecosystem services benefi ciaries and ensuring
that critical fl ow paths of ecosystem services are not
interrupted.
How can ecosystem fl ows be incorporated by
industry-led initiatives
It is important that businesses are able to understand their
dependence and impact on ecosystem services in a holistic
way, in the context of the broader landscape. To ensure
this is covered in a consistent manner, the assessment of
ecosystem services should be an integral part of En viron-
mental Impact Assessments. Considerations should not
only be for a specifi c site but also help in dustry understand
how services are interconnected to predict upstream and
downstream consequences. This will ultimately support
an assessment of dependency, which from the perspective
of industry will ensure the sustainability of supply of those
services that the industry depends upon.
Adaptive management – an opportunity
Risk is inherent to any decision about extracting resources,
building infrastructure, and adhering to a fl uctuating
mar ket economy in a globalised world. Businesses
face uncertainty regarding the amplitude of impacts in
space and time. The fl ow of services from terrestrial, to
coastal, and to marine ecosystems can serve as a useful
framework for managing risk and uncertainty. Businesses
can identify and rate key actions and operations that have
higher or lower probability to impact ecosystem service
sources, ecosystem service benefi ciaries and fl ow paths.
Environmental decisions that are typically affected by
high levels of uncertainty are, for example, those related
to establishing sustainable harvest levels (e.g. with
fi sheries) and to containing hazards to human health
and to supplies of water and food. In particular, high
uncertainty surrounds the existence and identifi cation of
ecological thresholds beyond which ecosystems are not
able to provide a continuous fl ow of goods and services.
In conditions of high uncertainty, decision making can be
enhanced by adopting an adaptive management approach.
Adaptive management involves fl exibly adjusting deci-
sions to the changing environmental and social contexts,
especially in face of the complex interactions between
terrestrial, coastal and marine systems. While businesses
have well established directives on how to manage risk
through environmental impact assessment protocols, ad-
op ting an adaptive management framework could result in
a more comprehensive assessment of impacts on the use
of ecosystem services from points of origin to areas where
benefi ciaries are located.
Securing private sector action – SWOT analysis
There are clear advantages to be had for the private
sector in incorporating ecosystem fl ows into business
strategies. There are many potential ways in which
this concept can be integrated, though there remain a
number of challenges to securing private sector action.
Figure 14 illustrates a SWOT analysis for integrating
ecosystem fl ow concept into EIAs, risk assessments and
any mitigation processes.
There is a series of challenges to be overcome in order
for the ecosystem fl ow concept to be integrated into
risk assessment and mitigation processes. Nonetheless,
innovation and technology can potentially minimise
potential damage to ecosystems and mitigate impacts
that may already be occurring, and this creates signifi cant
new business opportunities. Growing awareness of
the value of ecosystem fl ows and the interconnections
between ecosystems and their services is likely to bring
signifi cant competitive advantages for those industries at
the forefront.
Application for Business and Industry 43
Figure 14 – A SWOT analysis for integrating ecosystem fl ow concept into EIAs, risk assessments and any mitigation
processes.
Strengths Weaknesses
• Use of ecosystem services tools
• Development of policies and frameworks to incorporate
fl ow issues in the company’s activities
• Improved risk assessment
• Improved community relations
• Lack of reliable and accessible data on the distribution
of ecosystem services
• Limited understanding of how impacts propagate across
interconnected systems and of how to assess envir-
onmental costs over multiple affected ecosystems and
dimensions (e.g., environmental, social cultural, etc.)
Opportunities Threats
• Decrease regulatory uncertainty
• Develop an Adaptive management that can allow
modifi cation of the strategic plan
• Integrate Environmental Impact Assessment and Eco-
system Services Assessment
• Develop Early Screening Tools
• Apply tools to facilitate the transition from policy to
performance
• Use tools and dataset developed in context of cross-
sectoral partnerships
• Uncertainty on prediction of ecosystem changes
44 Framing the flow
How information on fl ows can improve marine
and coastal management
Understanding ecosystems and their interconnected
elements, as well as the linkages between ecosystems, is
key to improving environmental management in general,
and marine policies in particular. Conversely, ignoring
the interconnections between ecosystems and the fl ow
of ecosystem processes and services carries the risk of
ecosystems deteriorating despite management effort,
with consequent loss in services. Information on fl ows
can allow planners to make the case for truly integrated
management approaches, where linking watershed
man agement, coastal zone management, and marine
ecosystem-based management, can potentially so much
improve management effi ciency overall. Such information
also allows decision makers opportunities to better
evaluate trade-offs and make informed choices, and can
enhance leadership potential among a range of people.
Across all scales of governance, information on fl ows
provides impetus for improved, more holistic management.
Such knowledge can help spur international agreements
(both regional and global) as well as transboundary co-
operation (bilateral and others). At national scales, know-
ledge about fl ows will enhance nascent Marine Spatial
Planning and Comprehensive Ocean Zoning initiatives, as
well as sustainable-use programs such as certifi cation, en-
vironmental taxation and subsidy policies (for an example,
see Box 1 on Great Barrier Reef Marine Park Rezoning).
At more local scales, information on fl ows can help build
capacity for effective coastal and marine management,
Chapter Five
Implications for Policy Makers and Practitioners
by generation and sharing of information as well as
institutional networking. Information on fl ows should
be made available to agencies in the developing world,
which may not have the capacity and resources to derive
such information independently.
Better engaging the private sector in conservation and
environmental policy is necessary. Information on fl ows
could promote creation of new sources of conservation
and management funds through Payments for Ecosystem
Services (PES), providing opportunities for private sector
investment to complement public sector management.
At the same time, the prospect of being able to develop
market mechanisms to support conservation and
supplement government-based management can be
used to stimulate policy reform that enables market
development.
Information on fl ows can raise general public awareness
about the interconnectedness of ecosystems and the
intrinsic and immutable relationship between ecosystems
and human well-being, highlighting the critical link bet-
ween ecosystem health and human health. The publication
of the Millennium Ecosystem Assessment (MA, 2005)
provides an example of how access to appropriate in-
formation can signifi cantly raise the profi le of ecosystem
services and their critical role in sustainable development
processes (see below).
Examples of how this awareness can be incorporated into
practical policy and legislative measures are beginning to
gain ground (see Box 2).
Box 1: Using information on fl ows to design rezoning of the Great Barrier Reef Marine Park
The Great Barrier Reef Marine Park (GBRMP) is a vast multiple-use area spanning some 350,000km
2
of ocean adjacent
to the Queensland coast of Australia. Management of the GBR Marine Park presents the same sorts of challenges that
management of any complex suite of marine and coastal habitats provides, including how the management authority
can use scientifi c information not only to regulate activities in the protected area, but also to infl uence activities in
adjacent areas of land and freshwater that also affect the condition of the park’s highly valued reef ecosystems.
Between 1999 and 2004, the Great Barrier Reef Marine Park Authority (GBRMPA) undertook a complex planning and
consultative program to develop a new zoning plan for the GBR Marine Park. The primary aim of the program was to better
protect the range of biodiversity in the Great Barrier Reef, by increasing the ‘no-take’ area and including representative
examples of all different habitat types. A further aim was to minimise the impacts on the existing users of the marine
park. A comprehensive program of rezoning, strongly based on the best available biological, physical, social, economic,
and cultural sciences was achieved in 2004, after extensive public consultation. Information on connectivity between
different portions of the vast reef system, such as source areas for larval recruits and eventual settlement (sink) areas,
as well as connections between freshwater, estuarine and the marine areas of the reef complex helped guide decision-
making. The fi nal rezoning plan meets the aims of ensuring protection of all bioregions in no-take zones while minimising
the impact on reef users.
Implications for Policy Makers and Practitioners 45
Box 2: Recognising ecosystem service fl ows in policy
An increasing number of initiatives world-wide are highlighting the importance of the linkages between ecosystems
and promoting their incorporation into policy on the management of the environment.
UNEP’s Hilltops 2 Oceans (H
2
O) Partnership was launched at the WSSD in 2002 to highlight how water fl ows and river
systems constitute highways of “... both life and death, prosperity and poverty …”, providing essential water supplies
but also transporting pollution, sediments and pathogens over large distances from the hilltops to the oceans.
The US-supported Whitewater to Bluewater Initiative, also launched at the WSSD, has also been working to strengthen
national and regional institutional capacity to implement cross-sectoral management of watersheds and marine
ecosystems. Particular emphasis has been given to promoting better governance arrangements and cooperation
mechanisms and engaging with the private sector to improve water, land and coastal management through the
application of a ‘Ridge-to-Reef’ approach.
At the national level, South Africa’s Water Law of 1998 provides an example of the incorporation of similar approaches
into national policy. The law explicitly recognises the linkages between upstream water use and the health of
downstream ecosystems such as estuaries and promotes efforts to improve agricultural practices in catchments and
ensure minimum fl ow requirements for healthy freshwater and estuarine systems. In the UK, the 2009 Marine and
Coastal Access Act is a new marine planning system designed to bring together the conservation, social and economic
needs of England’s coastal and marine areas. Similarly the European Union (EU) has worked for the last 3 years to
develop a common approach (‘roadmap’) to maritime spatial planning (not a direct competence of the EU but of the 27
Member States). The roadmap (http://ec/europa/eu/maritimeaffairs/spatial_planning_en.html) is based on 10 principles
to guide Member States development of their own maritime spatial plans and, in particular, a shared approach to be
applied in the Exclusive Economic Zones. A common EU maritime spatial planning approach would be key to successful
implementation of the new EU marine environmental law. The 2008 Marine Strategy Framework Directive (http://eur-
lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:32008L0056:EN:NOT) facilitates maintaining or improving the
integrity of marine ecosystem functions and services by asking Member States to develop marine strategies to achieve
‘good environmental status’ of European marine waters by 2020. In this way, the Marine Strategy Framework Directive
constitutes the vital environmental component of the 2007 EU’s Integrated Maritime Policy, designed to achieve the full
economic potential of oceans and seas in harmony with the marine environment.
In the end, we will conserve
only what we love, we will love
only what we understand and
we will understand only what
we are taught.
– Baba Dioum, Senegalese
conservationist
46 Framing the flow
Challenges for policy processes in dealing with
ecosystem service fl ows
Even within single ecosystems, the policy processes
involved in dealing with complex interactions that do not
necessarily correspond to institutional, administrative
and sectoral boundaries are challenging. Dealing with
fl ows of ecosystem services is even more demanding.
Institutions and policy makers, who are often used to
addressing single sectors or spheres of concern, will have
to deal with an even more complex set of interactions
between different geographical areas, administrative and
political groups, and possibly even cultures and nations.
This will mean developing new and more holistic, cross-
sectoral approaches to policy formulation.
Linking policy decisions to policy outcomes –
what happens on the ground
Often the ways in which statements of policy will be trans-
lated into action on the ground are not clearly defi ned. This
leaves too much room for the familiar situation where the
‘right’ policies are in place but no impacts are perceived
because of failures in implementation. Of course, this does
not apply solely to policies dealing with the management
of ecosystem fl ows, but the more complex the reality being
addressed through policy, the more important it becomes
for linkages between policy decisions, implementationand
impacts to be carefully thought through. This involves un-
der standing all the levels involved in policy developmentand
the different spheres through which policy results can be
achieved. The accompanying fi gure (Figure 15 tries to show
this in relation to management of ecosystem service fl ows.
It must be understood that policy decisions about eco-
system service fl ows will have impacts not only on
ecosystems, but above all on people. They are likely to
affect people’s access to services (including ecosystem
services), the governance context in which they live, the
ways in which they create and sustain livelihoods for
themselves and their families, and on the options open
to them and the choices they can make about the future.
Dealing with complex sets of stakeholders and
agencies
The variety of stakeholders involved in policy relating to
Figure 15 – Diagram illustrating how ecosystem service
fl ows are nested in a series of layers of interaction, from
the stakeholders and agencies directly concerned,
to the area of power and processes through the insti-
tutional and policy context. The arrows emphasise the
need to understand how those services are transformed by
different stakeholders into livelihood outcomes, services,
income, etc., what are the various agencies, service
providers and governance arrangements that play a role
in managing or affecting those ecosystem services, the
institutional and policy context in which they operate, and
the power relations that infl uence this context.
Implications for Policy Makers and Practitioners 47
eco system fl ows is potentially high. But understanding
these arenas for management action, and the roles,
interests, relative infl uence, and responsibilities of the
different stake holders and agencies involved, is critical.
This requires a proper appreciation of how to carry out
in-depth stakeholder and institutional analysis, moving
beyond simply identifying who these stakeholders are,
to understanding what their roles might be in the ma-
nagement process.
This needs to be complemented by a more flexible
and creative approach to working with these sets of
stake holders and agencies. Those promoting the
manage ment of ecosystem flows need to move
beyond the ‘multi-stakeholder workshop’ to develop
mechanisms for creating sustained engagement in the
management process by different sets of interested
parties. Particularly in less-developed countries, and
where poor and marginalised groups may be affected
by new management initiatives, attention is required
to developing sustainable means of engaging these
groups in decision-making. This means enhancing
their capacity to make their voices heard, and ensuring
that they have access to information about ecosystem
management and the capacity to use that information
to make informed choices about how to adapt to new
management measures.
Informing and infl uencing institutions and policy
makers
In spite of the complexity of the institutional and policy
context, it is important to be systematic in the process of
informing and infl uencing elements within that context.
At the policy and institutional level, different individuals
and interest groups will be involved, all with specifi c
concerns in relation to the process, as well as different
levels of infl uence on potential outcomes. Understanding
these thoroughly will be integral to identifying key le-
verage points where information and advocacy can be
targeted for maximum effect.
Having appropriate information about ecosystem service
fl ows is critical to the informing and infl uencing process.
The primary results of research on ecosystem service
48 Framing the flow
fl ows is likely to be complex, with multiple sets of variables,
and often be bewildering for non-specialists, including
policy makers. A key challenge therefore is to ensure
effective communication, and there will typically be a need
to distill the outputs of analysis into simple, accessible and
comprehensible messages that can actually inform policy
makers and be used by them in their decision making.
Dealing with trade-offs and resolving confl icts
Almost any form of ecosystem management can generate
winners and losers and, consequently, give rise to confl ict.
Failures in promoting better ecosystem management are
consistently linked to failure to predict and address these
confl icts rather than to purely technical issues. Providing
stakeholders with transparent and convincing mechanisms
for analysing the trade-offs involved and in addressing the
confl icts which arise is therefore crucial. Policy and decision
makers need to have the appropriate tools incorporated in
their management approaches (Brown et al., 2001).
Understanding power, process and the ‘rules of
the game’
Formally recognised policy development is embedded in a
context of power and processes which will always strongly
condition both the process itself and the policy outcomes
that it generates. This context is dynamic, complex and
particularly diffi cult to understand as it is made up of
(often unwritten) ‘rules of the game’ – historical precedent,
cultural norms and surrounding social and economic
structures. However, those promoting new forms of man-
agement ignore these aspects at their peril, as it is often
this context that will dictate what actually happens, as
opposed to what is supposed to happen (Lobo, 2008).
There is no universal protocol available, but developing
appropriate tools for policy makers to address this context
of power and processes would greatly enhance chances
of uptake of new policy approaches to ecosystem services
management. In particular, it could help to determine
what is possible and what is not possible and what
strategies for promoting new management processes are
most appropriate in any given setting.
Ways forward: using information to infl uence
policy
The important challenges that remain in integrating an
appreciation of the importance of ecosystem fl ows into
policy processes are clear. The Millennium Ecosystem
Assessment (MA, 2005) discussed in Box 3, has illustrated
how appropriate information can play a key role in raising
the profi le of ecosystem services. In particular, it has
increased policy makers’ understanding of how the key
challenge of addressing poverty worldwide is intimately
linked with our capacity to better manage, and preserve,
ecosystems and the services they provide.
However, there is still an overwhelming lack of integration
of knowledge on ecosystem services and poverty. Rarely is
information on ecosystem services and poverty generated,
analysed, stored or used jointly by relevant institutions in
developing countries. Secondly, knowledge is not shared
between and within countries, and there are widespread
diffi culties with lack of access to existing information.
As yet, there is little precise guidance available to show
exactly how ecosystem services can contribute towards
poverty alleviation; this is not, for example, a topic usually
addressed in country-specifi c Poverty Reduction Strategy
Papers (PRSPs). There are some, limited, suggestions of
how Payment for Ecosystem Services (PES), Pro tected
Areas or Community-Based Natural Resource Manage-
ment (CBNRM) may provide benefi ts, but no systematic
or comprehensive analysis exists to adequately guide
policy.
Providing this sort of guidance remains a key challenge
for the future.
Implications for Policy Makers and Practitioners 49
Box 3: Information and policy – the case of the Millennium Ecosystem Assessment
The publication of the Millennium Ecosystem Assessment (MA) in 2005 provided a landmark example of how
information can be used to raise the profi le of ecosystem services and infl uence policy agendas worldwide. In particular,
the MA framework provided a useful starting point for conceptualising holistically the linkages between ecosystems,
the services they provide and human well-being. Particularly important was the establishment of direct links between
key areas of concern for policy makers, such as poverty alleviation and the maintenance of ecosystem health and
service fl ows. The MA highlighted how fi ndings from around the world suggest that the trends and changes infl uencing
ecosystem services are having profound impacts on the poor, leading to further pressure on resources.
The MA delivered a stark message: our management of the world’s ecosystems is already causing signifi cant harm
to some people, especially the poor, and unless addressed will substantially diminish the long-term benefi ts we all
obtain from ecosystems. One of the major gaps identifi ed by the MA concerns the lack of integration of concerns
about ecosystem services and poverty, and the fact that “very few macro-economic responses to poverty reduction
have considered the sound management of ecosystem services as a mechanism to meet the basic needs of the poor.
Importantly, it also highlighted how failure to incorporate considerations of ecosystem management in the strategies
being pursued to achieve many of the eight Millennium Development Goals will undermine the sustainability of
progress that is made toward the goals and targets associated with poverty, hunger, disease, child mortality and
access to water” (Chopra et al., 2005).
Since the publication of the MA a number of important scientifi c studies have emerged which have advanced knowledge
in this fi eld and illustrated the complexities involved in incorporating ecosystem service fl ows into policy and decision
making. Recent research has shown how measures to conserve biodiversity will not necessarily correspond to
measures to maximise ecosystem services. The relationships between different sets of priorities such as conservation,
service provision and optimal use are rarely simple and the importance of seeking trade-offs and synergies is becoming
increasingly apparent (Srinivasan et al., 2008; Turner & Fisher, 2008).
As the initial fi ndings of the MA have been built on, research gaps identifi ed by the MA have started to be fi lled, but
at the same time new gaps are opening as the fi eld of science directed towards understanding ecosystem services
and human well-being expands. For example, a recent paper highlighted the need to identify appropriate institutions
and incentives to guide investments in ecosystem services, noting three key areas that in particular require further
work: ecosystem production functions and service mapping; the design of appropriate fi nance, policy and governance
systems; and how these solutions can be implemented in diverse biophysical and social settings (Barbier et al., 2008;
Naidoo et al., 2008; Kareiva et al., 2007).
50 Framing the flow
This publication presents a framework for conceptualising
the connectivity between coastal ecosystems across
environ mental, economic, social, and management
contexts. It presents innovative approaches to better
understand, protect and value ecosystem services from
linked habitats, and elucidate the trade-offs implied by
different management decisions and potential loss of
ecosystem services.
Key recommendations of this publication are summarised
below.
• In converting ecosystem functions (regulation, habi-
tat, production, and information) to a quantitative
value, the following ecological and sociological as-
pects need to be considered:
Ecological:
• Non-linearity and overlap in ecosystem ser-
vices;
• The large extent of the entire, linked eco-
system truly responsible for service delivery;
• The diffi culty of evaluating some ecosystem
services, because of temporal and seasonal
factors, for example.
Socio-ecomical:
• Recognition that the value assigned to the
natural resources is more an indicator for
decision-makers than the ‘true’ value of the
ecosystem;
• The fact that value changes rapidly and that
this may condition different decisions during
the time;
• The opportunity to create a hierarchy of op-
tions;
• The principle of equity among benefi ciaries;
• The provision of desirable features of the
natural environment to future generations.
• The use of spatial planning tools and modelling pro-
cesses should be encouraged to support valuation
process and the identifi cation of regions more likely
to provide higher or lower levels of value.
• In order to improve environmental performance,
reduce risk, and increase public support, it is suggested
that the ecosystem fl ow concept be embedded in
business strategies in the following ways:
• Incorporating knowledge on the spatial fl ows of
ecosystem services across landscapes in order
to increase opportunities to identify mitigation
options and ways to positively infl uence existing
pathways to reach more benefi ciaries or specifi c
groups of marginalised benefi ciaries;
• Evaluating potential business impacts
over the entire array of benefi ciaries that
depend on a given ecosystem, whether in
the immediate vicinity or further along the
marine-terrestrial gradient;
• Carrying out effective risk management
through the maintenance of critical pathways
of ecosystem services and understanding how
these pathways can change as a response to
interventions on the landscape;
• Use the concept of ecosystem service
fl ows as a framework for managing risk and
uncertainty. Businesses can identify and rate
key actions and operations that have higher or
lower probability to impact ecosystem service
sources, benefi ciaries, and fl ow paths;
• The use of early screening tools;
• The adoption of datasets developed in the
context of cross-sectoral partnerships;
• The development of adaptive management
strategies in order to be able to fl exibly
react to the complex interactions between
terrestrial, coastal and marine systems, and
to potentially result in a more comprehensive
assessment of impacts and use of ecosystem
services from points of origin to areas where
benefi ciaries are located;
• Ecosystem service assessment should be inte -
grated into the Environmental Impact Assess-
ment framework in order consistently to eluci-
date the industrial dependence and impact on
ecosystem services. Attention must be given
not only to a specifi c site but also to potential
upstream and downstream consequences,
Key Recommendations
Key Recommendations 51
aiming to generate a com prehensive picture of
dependency and so fa cilitate sustainability.
• Enhancing the understanding of ecosystem elements
and linkages between ecosystems among policy-
makers and practitioners should be prioritised in
order to improve marine environmental management.
Information on fl ows should be used in environmental
planning to develop effective and truly integrated
management approaches, especially those bridging
the divide between watershed management, coas-
tal zone management and marine ecosystem-based
management.
• More comprehensive management approaches should
be developed through awareness of the linkages bet-
ween coastal ecosystems and maintenance of eco-
system service fl ows, increasing the recognition by
managers of the need to protect the natural capi tal
that generates these services, together with the
underlying ecological connections that regulate bene-
fi t fl ow across systems.
• Explore ways of communicating simple, accessible
and comprehensible information on natural resource
valuation to policy-makers and managers in order to
ensure informed decision-making is taking place in
new and transboundary governance structures.
• Tools for resolving confl icts and trade-offs should be
embedded into analysis and development of man-
agement of linked habitats and ecosystem fl ows.
52 Framing the flow
Adaptation
Adjustment in natural or human systems to a new or
changing environment. Various types of adaptation can be
distinguished, including anticipatory and reac tive adap-
tation, private and public adaptation, and auto nomous
and planned adaptation.
Biodiversity
The full range of natural variety and variability within
and among living organisms, and the ecological and
environmental complexes in which they live. It includes
genetic diversity within species, the diversity of species
in ecosystems and the diversity of habitats and eco-
systems.
Biome
The largest unit of ecological classifi cation that is
convenient to recognize below the entire globe. Terrestrial
biomes are typically based on dominant vegetation
structure (e.g. forest and grassland). Ecosystems within
a biome function in a broadly similar way, although they
may have very different species composition. For example,
all forests share certain properties regarding nutrient
cycling, disturbance, and biomass that are different from
the properties of grasslands. Marine biomes are typically
based on biogeochemical properties.
Carbon capture and storage
A process consisting of the separation of CO2 from in-
dustrial and energy-related sources, transport to a
storage location and longterm isolation from the atmo-
sphere (IPCC, 2007).
Carbon sequestration
The process of increasing the carbon content of a re-
servoir other than the atmosphere (Chopra et al., 2005).
Coastal systems
Systems containing terrestrial areas dominated by ocean
infl uences of tides and marine aerosols, plus nearshore
marine areas. The inland extent of coastal ecosystems
is the line where land-based infl uences dominate, up to a
maximum of 100 kilometres from the coastline or 100m
elevation (whichever is closer to the sea), and the outward
extent is the 50m-depth contour. See also System.
Connectivity
Allowing for the conservation or maintenance of con-
tinuous or connected habitats, so as to preserve move-
ments and exchanges associated with the habitat.
Driver
Those processes, either human induced or naturally pre-
sent, which alter an ecosystem’s natural function and
therefore may alter the delivery of ecosystem services.
Ecological linkage
A series (both contiguous and non-contiguous) of patches
which, by virtue of their proximity to each other, act as
stepping stones of habitat which facilitate the maintenance
of ecological processes and the movement of organisms
within, and across, a landscape (Molloy et al., 2007).
Eco-regional planning
A planning approach which aims to identify the conservation
value and production potential over large areas bound by a
shared set of ecological and biogeographic characteristics.
Ecosystem
A dynamic complex of plant, animal and microorganism
communities and their non-living environment interacting
as a functional unit (UNEP, 2006).
Ecosystem function
See Ecosystem process.
Ecosystem integrity
Supporting and maintaining a balanced, integrated, adap-
tive community of organisms having a species composition,
diversity, and functional organisation comparable to that of
a natural habitat of the region (Jorgensen & Miller, 2000).
Ecosystem management
An approach to maintaining or restoring the composition,
structure, function, and delivery of services of natural
and modifi ed ecosystems for the goal of achieving sus-
tainability. It is based on an adaptive, collaboratively deve-
loped vision of desired future conditions that integrates
ecological, socioeconomic and institutional per spectives
applied within a geographic framework, and defi ned pri-
marily by natural ecological boundaries.
Glossary
Glossary 53
Ecosystem process
An intrinsic ecosystem characteristic whereby an eco-
system maintains its integrity. Ecosystem processes
include decomposition, production, nutrient cycling, and
fl uxes of nutrients and energy.
Ecosystem resilience
The ability of an ecosystem to respond and/or recover
from a disturbance and return to its equilibrium state, i.e.
a resilient ecosystem is one that is likely to recover more
rapidly than a less resilient one.
Ecosystem services
The benefi ts people obtain from ecosystems. These
include provisioning services such as food and water;
regulating services such as fl ood and disease control;
cultural services such as spiritual, recreational and cul-
tural benefi ts; and supporting services, such as nut rient
cycling, that maintain the conditions for life on Earth. The
concept ‘ecosystem goods and services’ is synonymous
with ecosystem services.
Ecosystem services fl ow
See Flow of services.
Ecosystem services pathway
See Ecological linkages .
Ecosystem-based adaptation
An approach which focuses on the protection of
ecological processes from human stressors with the
aim of building or improving the natural resilience of the
ecosystem in order to sustain the production of services
into the future.
Environmental services
See Ecosystem services.
Driver
Any natural or human-induced factor that directly or
indirectly causes a change in an ecosystem.
Driver, direct
A driver that unequivocally infl uences ecosystem pro-
cesses and can therefore be identifi ed and measured to
differing degrees of accuracy (compare Driver, indirect).
Driver, indirect
A driver that operates by altering the level or rate of
change of one or more direct drivers (compare Driver,
direct).
Eutrophication
The increase in additions of nutrients to freshwater or
marine systems, which leads to increases in plant growth
and often to undesirable changes in ecosystem structure
and function.
Flow of services
The movement of ecosystem services between the areas
that provide them and those that benefi t from these
services.
Habitat
The environment on which a given species or ecological
community depends for its survival. The environmentcan be
physical (e.g. rocky reefs or marine caves) or createdby liv-
ing organisms (e.g. seagrass meadows or deep coralbanks).
Landscape
An area of land that contains a mosaic of ecosystems,
including human dominated ecosystems. The term cultural
landscape is often used when referring to landscapes
containing signifi cant human populations or in which there
has been signifi cant human infl uence on the land.
Marine Spatial Planning
A public process of analysing and allocating the spatial and
temporal distribution of human activities in marine areas
to achieve ecological, economic and social objectives that
have been specifi ed through a political process (UNESCO).
Mitigation
An anthropogenic intervention to reduce negative or
unsustainable uses of ecosystems or to enhance sustain-
able practices (UNEP, 2006).
Ocean Zoning
Ocean zoning is a planning tool that allows a strategic
allocation of uses based on a determination of an area’s
suitability for those uses, and reduction of user confl icts
by separating incompatible activities.
Payment for Ecosystem Services
It is a voluntary arrangement in which one or more agents
(‘providers’) of an ecosystem service will receive agreed
compensation from one or more benefi ciaries (‘buyers’)
of ecosystem services, on the condition of sustaining the
provision of the ecosystem services.
Primary Productivity
The amount of production of living organic material through
photosynthesis by plants, including algae, measured over a
period of time.
Seascape
Large, multiple-use marine areas, defi ned scientifi cally
and strategically, in which government authorities, pri-
vate organizations, and other stakeholders cooperate to
conserve the diversity and abundance of marine life and
to promote human well-being.
Sink
Features or land-scape confi gurations that have the ability
of depleting the benefi ts as they fl ow from sources to
54 Framing the flow
benefi ciaries. They can be natural elements (e.g. levees
and visual blight) or human elements (users themselves).
Sustainable use (of an ecosystem)
Human use of an ecosystem so that it may yield a con-
tinuous benefi t to present generations while maintaining
its potential to meet the needs and aspirations of future
generations (UNEP, 2006).
System
In the Millennium Ecosystem Assessment, reporting units
that are ecosystem-based but at a level of aggregation far
higher than that usually applied to ecosystems. Thus the
system includes many component ecosystems, some of
which may not strongly interact with each other, that may
be spatially separate, or that may be of a different type to
the ecosystems that constitute the majority, or matrix, of
the system overall. The system includes the social and
economic systems that have an impact on and are affected
by the ecosystems included within it. Systems thus defi ned
are not mutually exclusive, and are permitted to overlap
spatially or conceptually (UNEP, 2006).
Threshold
See Tipping point.
Tipping point
The point at which a relatively small change in external
conditions causes a rapid change in an ecosystem. When a
tipping point has been passed, the ecosystem may no longer
be able to return to its state. The trespassing of the tipping
point often leads to rapid change of ecosystem health.
Trade-off
Management choices that intentionally or otherwise
change the type, magnitude, and relative mix of services
provided by ecosystems.
Transboundary
A function, service or process which crosses ecosystem
and/or political boundaries/delineations.
Trophic linkage
A descriptor of the energy transfer relationship between
organisms in a related food chain or web.
Acronyms 55
Acronyms
ARIES
CB
CBNRM
CGIAR
CV
EIA
EPA-SAB
EEZ
FIESTA
GBRMP
GBRMPA
HPM
IMM
InVEST
IUCN
MA
PES
NOAA
PRSP
PSS
SPAN
SWAT
SWOT
TCM
TEV
UNEP-GPA
UNEP-WCMC
UNESCO
US EPA
WaterGAP
WSSD
Artifi cial Intelligence for Ecosystem Services
Contingent behaviour
Community Based Natural Resource Management
Consultative Group on International Agricultural Research
Contingent valuation
Environmental Impact Assessment
Environmental Protected Areas – Science Advisory Board
Exclusive Economic Zone
Fog Interception for the Enhancement of Streamfl ow in Tropical Areas
Great Barrier Reef Marine Park
Great Barrier Reef Marine Park Authority
Hedonic price method
Integrated Marine Management
Integrated Valuation of Ecosystem Services and Tradeoffs
International Union for Conservation of Nature
Millenium Ecosystem Assessment
Payment for Ecosystem Services
National Oceanic and Atmospheric Administration
Poverty Reduction Strategy Papers
Policy Support System
Service Path Attribution Network
Soil and Water Assessment Tool
Strengths, Weaknesses, Opportunities and Threats
Travel cost method
Total economic value
United Nations Environment Programme Global Programme of Action
United Nations Environment Programme World Conservation Monitoring Centre
United Nations Education, Scientifi c and Cultural Organisation
Unites States Environmental Protection Agency
Water – Global Assessment and Prognosis
Word Summit on Sustainable Development
56 Framing the flow
EDITORS
Silvia Silvestri, UNEP-WCMC, Cambridge, UK
Francine Kershaw, UNEP-WCMC, Cambridge, UK
EDITORIAL ASSISTANCE
Brian Goombridge, Cambridge, UK
CARTOGRAPHY AND GRAPHICS
Riccardo Pravettoni, UNEP/GRID-Arendal, Arendal,
Norway
LAYOUT
Ian Bignall, Cambridge, UK
ACKNOWLEDGMENTS
We are very grateful for the inputs and advice we received
from the participants to the international workshop “Flow
of Ecosystem Services between Linked Habitats: from
Hilltops to the Deep Ocean” hosted by UNEP-WCMC in
Cambridge, UK, October 6-8, 2009.
LIST OF ADVISORS AND REVIEWERS
Nicola Barnard, Penny Stock, Matt Walpole, Terri
Young,
UNEP-WCMC, Cambridge, UK
Emily Corcoran, UNEP/GRID-Arendal, Arendal, Norway
Eva Gelabert, European Environment Agency, Copen-
hagen, Denmark
Luz M. Lodoño-Diaz, University of Connecticut, Con-
necticut, USA
James Spurgeon, Environmental Resources Manage-
ment, Oxford, UK
Virpi Hannele Stucki, Shell International, The Hague, NL
Sheila Vergara, University of the Philippines, Philippines
LIST OF CONTRIBUTORS
Chapter 1: Conceptualising Ecosystem Benefi ts
Across Land- and Seascapes
Carmen Lacambra, UNEP-WCMC, Cambridge, UK
Marea Hatziolos, The World Bank, Washington, DC, USA
Elizabeth Selig, Conservation International, Virginia, USA
William Cheung, University of East Anglia, Norwich, UK
Chapter 2: Capturing and Quantifying the Flow of
Eco system Services
Mark Mulligan, King’s College London, London, UK
Anne Guerry, NOAA, Washington, USA
Katie Arkema, The Natural Capital Project, Stanford
University, USA
Kenneth Bagstad, Ferdinando Villa, University of
Vermont, Vermont, USA
Silvia Silvestri, UNEP-WCMC, Cambridge, UK
Chapter 3: Valuing Ecosystem Services of Coastal
Habitats
Andrew Seidl, IUCN, Gland, Switzerland
Silvia Silvestri, UNEP-WCMC, Cambridge, UK
Nalini Rao, Conservation International, Virgina, USA
Chapter 4: Application for Industry and Business
Silvia Silvestri, Monica Barcellos, Sharon Brooks,
UNEP-WCMC, Cambridge, UK
Marta Ceroni, University of Vermont, Vermont, USA
Chapter 5: Implications for Policy Makers and
Practitioners
Tundy Agardy, Forest Trends, Washington, DC, USA
Anjan Datta, UNEP-GPA, Nairobi, Kenya
Robert Pomeroy, University of Connecticut, Con necticut,
USA
Philip Townsley, IMM, Viterbo, Italy
PHOTO CREDITS
1: Hank foto-UNEP/Still Pictures 2: iStockphoto/ Sergeo_
Syd
4: iStockphoto/Jet Tan 6: UNEP-WCMC/Nicola
Barnard
7: UNEP-WCMC/Charles Besancon 10-11: R.
Jeerawat Siriwikul-UNEP/Still Pictures
12: iStockphoto/
Sharon Metson 15: UNEP-WCMC/Sebastian Hennige
17: iStockphoto/Piero Malaer 19: Lay Cheng Cheah-
UNEP/Still Pictures 24: iStockphoto/David Freund 25:
UNEP/Charles Craval
27: iStockphoto/Duncan Noakes
31: UNEP-WCMC/Charles Besançon 35: Gerald Nowak/
WaterFrame/Still Pictures
38: UNEP-WCMC/Ed Green
40: Surachi Tolertmongkol-UNEP/Still Pictures 43:
iStockphoto/imagedepotpro 45: Lin Riran-UNEP/Still
Pictures 46-47: UNEP-WCMC/Carl J. Wantenaar 48:
UNEP-WCMC/Silvia Silvestri 51: iStockphoto/Matt Keal
Photogaphy 63: Demi-UNEP/Still Pictures 64: Borut
Furlan/WaterFrame/Still Pictures and Ethan Daniels/
WaterFrame/Still Pictures
Contributors and Reviewers
References 57
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