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Wetland ecosystem services


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Wetlands provide important and diverse benefi ts to people around the world, contributing provisioning, regulating, habitat, and cultural services. Critical regulating services include water-quality improvement, fl ood abatement and carbon management, while key habitat services are provided by wetland biodiversity. However, about half of global wetland areas have been lost, and the condition of remaining wetlands is declining. In New Zealand more than 90% of wetland area has been removed in the last 150 years, a loss rate among the highest in the world. New Zealand Māori greatly valued wetlands for their spiritual and cultural significance and as important sources of food and other materials closely linked to their identity. The remaining wetlands in New Zealand are under pressure from drainage, nutrient enrichment, invasive plants and animals, and encroachment from urban and agricultural development. In many countries, the degradation of wetlands and associated impairment of ecosystem services can lead to signifi cant loss of human well-being and biodiversity, and negative long-term impacts on economies, communities, and business. Protection and restoration of wetlands are essential for future sustainability of the planet, providing safety nets for emerging issues such as global climate change, food production for an increasing world population, disturbance regulation, clean water, and the overall well-being of society.
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Wetlands are among the world’s most productive and valu-
able ecosystems. They provide a wide range of economic, social,
environmental and cultural bene ts – in recent times classi ed as
ecosystem services (Costanza et al. 1997). These services include
maintaining water quality and supply, regulating atmospheric
gases, sequestering carbon, protecting shorelines, sustaining
unique indigenous biota, and providing cultural, recreational and
educational resources (Dise 2009). Despite covering only 1.5%
of the Earth’s surface, wetlands provide a disproportionately high
40% of global ecosystem services (Zedler and Kercher 2005).
They play a fundamental part in local and global water cycles
and are at the heart of the connection between water, food, and
energy; a challenge for our society in the context of sustainable
management. The Economics of Ecosystems and Biodiversity
for water and wetlands (TEEB 2013) was recently published
to help decision-makers prioritise management and protection.
The TEEB (2013) study translated the values of ecosystem
services into dollar terms (Table 1). For instance, the economic
value of inland wetland ecosystem services was estimated at up
to US$44,000 per hectare per year. Equivalent values for other
wetland biomes were US$79,000 for coastal systems, $215,000
for mangroves and tidal marshes and $1,195,000 for coral reefs.
The values, representing a common set of units using bene t
transfer, allow comparison across services and ecosystems. On
this basis these studies show that of the 10 biomes considered,
wetlands have among the highest value per hectare per year
(Figure 1), exceeding temperate forests and grasslands.
Despite the high value of ecosystem services derived from
wetlands, around the world they have been systematically
drained and lled to support agriculture, urban expansion, and
other developments. In total, about 50% of the world’s original
wetland area has been lost, ranging from relatively minor losses
in boreal countries to extreme losses of >90% in parts of Europe
(Mitsch and Gosselink 2000a). Wetlands that remain, whether in
the developed or developing world, are under increasing pressure
from both direct and indirect human activities; and despite strong
regulatory protection in many countries, wetland area and condi-
tion continue to decline (National Research Council 2001; TEEB
2013). Many wetlands now require urgent remediation if key
functions and associated ecosystem services are to be maintained.
In New Zealand, more than 90% of the original extent of
wetlands has been lost in the last 150 years (Gerbeaux 2003;
Ausseil et al. 2011b; Figure 2), one of the highest rates and extent
of loss in the developed world (Mitsch and Gosselink 2000a).
The South Island has 16% of its original wetland area
remaining; the more populated and intensively devel-
oped North Island has only 4.9% (Ausseil et al. 2011a).
Although legislation identi es protection of
wetlands as a matter of national importance (New
Zealand Resource Management Act 1991), many
wetlands continue to degrade through reduced water
availability, eutrophication, and impacts from weeds
and pests. The past decade has seen considerable
funding injections into wetland restoration projects,
for example the Department of Conservation’s Arawai
Kākāriki Project, and the Biodiversity Advice and
Condition Fund, as well as many smaller funding and
grants available at regional and local levels (Myers et al.
2013). These funds are targeted mainly at enhancing
Beverley R. Clarkson1, Anne-Gaelle E. Ausseil2, Philippe Gerbeaux3
1 Landcare Research, Private Bag 3127, Hamilton 3240 New Zealand
2 Landcare Research, Palmerston North, New Zealand
3 Department of Conservation, Christchurch, New Zealand
ABSTRACT: Wetlands provide important and diverse bene ts to people around the world, contributing provisioning, regulating, habitat,
and cultural services. Critical regulating services include water-quality improvement, ood abatement and carbon management, while
key habitat services are provided by wetland biodiversity. However, about half of global wetland areas have been lost, and the condition
of remaining wetlands is declining. In New Zealand more than 90% of wetland area has been removed in the last 150 years, a loss rate
among the highest in the world. New Zealand Māori greatly valued wetlands for their spiritual and cultural signi cance and as impor-
tant sources of food and other materials closely linked to their identity. The remaining wetlands in New Zealand are under pressure
from drainage, nutrient enrichment, invasive plants and animals, and encroachment from urban and agricultural development. In many
countries, the degradation of wetlands and associated impairment of ecosystem services can lead to signi cant loss of human well-being
and biodiversity, and negative long-term impacts on economies, communities, and business. Protection and restoration of wetlands are
essential for future sustainability of the planet, providing safety nets for emerging issues such as global climate change, food production
for an increasing world population, disturbance regulation, clean water, and the overall well-being of society.
Key words: climate regulation, ecological integrity, economic valuation, ood regulation, natural ecosystem, restoration.
Clarkson BR, Ausseil AE, Gerbeaux P 2013. Wetland ecosystem services. In Dymond JR ed. Ecosystem services in New Zealand – conditions and trends. Manaaki
Whenua Press, Lincoln, New Zealand.
FIGURE 1 Range and average of total monetary value of bundle of ecosystem services
per biome: total number in brackets, average as a star (from de Groot et al. (2012),
redrawn in TEEB (2013)).
biodiversity; however, the outcome generally supports sustaining
healthy functioning wetlands and delivering a range of wetland
ecosystem services.
Although there are many studies quantifying wetland
ecosystem services around the world, for example more than
200 case studies were synthesised by Costanza et al. (1997) and
Schuyt and Brander (2004), relatively few have been published in
New Zealand. Our wetlands are compositionally distinctive with
c. 80% of vascular plant species endemic, but functional processes
(e.g. decomposition rates and bog development) have been
shown to be similar to results found in the Northern Hemisphere
(Agnew et al. 1993; Clarkson et al. 2004a, b, in review; Hodges
and Rapson 2010). This chapter summarises current knowledge
and approaches to quantifying wetland ecosystem services from
around the world and, where possible, provides examples and
case studies from New Zealand.
What are wetlands?
Wetlands are lands transitional between terrestrial and aquatic
systems where an oversupply of water for all or part of the year
results in distinct wetland communities. The New Zealand
Resource Management Act (1991) de nes wetlands as ‘perma-
nently or intermittently wet areas, shallow water, and land water
margins that support a natural ecosystem of plants and animals
adapted to wet conditions’. This de nition is similar to others
around the world (e.g. Section 404 of the USA Clean Water Act).
Many countries use the international Ramsar Convention de ni-
tion, which is broader and encompasses human-made wetlands
and marine areas extending to 6 m below low tide (Ramsar 1982).
The focus of this chapter is inland (freshwater) wetlands, i.e.
those associated with riverine and lacustrine systems, particularly
swamp and marsh, and palustrine wetlands including fen and
bog, which together represent the main functional types present
in New Zealand (Johnson and Gerbeaux 2004).
TABLE 1 Monetary valuation of services provided by freshwater wetlands ( oodplains, swamps/marshes and peatlands) per hectare per year, and relative
(TEEB 2013)
Mean global
value (Int1$2007)
(de Groot et al.
Maximum global
(TEEB 2013)
Wanganui Region
(NZ$2006) (van den
Belt et al. 2009)
New Zealand
(Patterson and Cole
TOTAL 25,682244,597 43,320 52,5303
Provisioning services 1,659 9,709 17,026 84
Food 614 2,090 104
Fresh water supply 408 5,189 16,814 84
Raw materials 425 2,430 108
Genetic resources
Medicinal resources 99
Ornamental resources 114
Regulating services 17,364 23,018 20,339 45,217
In uence on air quality 586 711
Climate regulation 488 351
Moderation of extreme events 2,986 4,430 16,017 19,530
Regulation of water ows 5,606 9,369 66 20,500
Waste treatment 3,015 4,280 3,670 4,476
Erosion prevention 2,607
Maintenance of soil fertility 1,713 4,588
Biological control 948
Habitat services 2,455 3,471 971
Lifecycle maintenance 1,287 917 971 1,175
Gene pool protection 1,168 2,554
Cultural 4,203 8,399 4,982 6,054
Aesthetic 1,292 3,906 3,896
Recreation/tourism 2,211 3,700 1,086 1,313
Inspiration for culture, art, design 700 793 4,741
Spiritual experience
Cognitive information
1 International dollar = US$1. This is a hypothetical unit of currency to standardise monetary values across countries. Figures must be converted using the country’s
purchasing power parity instead of the exchange rate.
2 Based on 168 studies, with standard deviation of $36,585, median value of $16,534, minimum value of $3,018 and maximum value of $104,924 (Int$2007 ha–1 yr–1).
3 This is based on supporting, regulating, provisioning and cultural values without passive value for comparison purposes.
Why are wetlands such important providers of ecosystem
Wetlands are able to provide high-value ecosystem services
because of their position in the landscape (Zedler 2006) as recipi-
ents, conduits, sources, and sinks of biotic and abiotic resources.
They occur at the land–water interface, usually in topographi-
cally low-lying positions that receive water, sediments, nutrients
and propagules washed in from up slope and catchment. Within
catchments, wetlands allow sediments and other materials to
accumulate and settle, providing cleaner water for sh, wildlife
and people. The combination of abundant nutrients and shallow
water in receiving wetlands promotes vegetation growth, which
in turn affords habitat and food for a wide range of sh, birds and
invertebrates. Wetlands also accumulate oodwaters, retaining
a portion, slowing ows, and reducing peak water levels, which
cumulatively have signi cant roles in ood abatement.
The near permanent wetness of wetland ecosystems is equally
important. Saturated areas have very low levels of oxygen,
particularly in the ‘soil’ where it is accessed by roots and micro-
organisms (Sorrell and Gerbeaux 2004). Such anoxic conditions
promote changes in critical microbial processes resulting in
anaerobic nutrient transformations that make nitrogen available
for use by plants (nitrogen xation) and convert nitrates into
harmless gas, thereby improving water quality (denitri cation).
Having anoxic and aerobic conditions in close proximity is a
natural property of shallow water and wetlands (Zedler 2006).
The anoxic conditions also promote peat accumulation, locking
up carbon, which in turn regulates atmospheric carbon levels and
helps cool global climates (Frolking and Roulet 2007).
Wetlands provide a wide range of ecosystem services vital for
human well-being. These are discussed below following the clas-
si cation of TEEB (2010), which relates to the benets people
obtain from ecosystems.
Provisioning services
Wetlands produce an array
of vegetation, animal and
mineral products that can be
harvested for personal and
commercial use. Perhaps the
most signi cant of these is sh,
the main source of protein for
one billion people worldwide,
and providing employment
and income for at least 150
million people through a
shing industry (Ramsar
2009e). Rice is another impor-
tant food staple and accounts
for one- fth of total global
calorie consumption. Other
important food products grown
in wetlands include sago and
cooking oil (from palms from
Africa), sugar, vinegar, alcohol,
and fodder (from the Asian
nipa palm), and honey (from
mangroves). Wetland products
also include fuelwood, animal
fodder, horticultural peat, traditional medicines, bres, dyes and
In New Zealand, wetlands are traditional mahinga kai
or resource gathering areas (Best 1908; Harmsworth 2002).
Early Māori harvested harakeke (NZ ax; Phormium tenax)
for clothing, mats, kete (baskets) and rope (Wehi and Clarkson
2007), kuta (bamboo spike sedge; Eleocharis sphacelata) for
weaving and insulation (Kapa and Clarkson 2009), raupō (Typha
orientalis) for thatching and pollen-based food, dried moss for
bedding, poles of mānuka (Leptospermum scoparium) for pali-
sades, and culturally important plants for rongoā (medicinal
use). As breeding grounds for tuna (eels; Anguilla spp.), inanga
(whitebait; Galaxias spp.) and other sh, as well as sustaining an
abundance of birdlife, wetlands were a signi cant source of food.
More recent wetland products include Sphagnum moss, a water-
retaining horticultural medium for orchids, mostly harvested on
the West Coast of the South Island (worth NZ$8.5–18 million
per year; Hegg 2004), and horticultural peat, which is mined
at ve bog sites in New Zealand (de Lacy 2007). In addition, a
highly valued honey with signi cant medicinal properties based
on mānuka, a heath shrub species widespread in New Zealand
wetlands, is a burgeoning lucrative industry (Stephens et al.
Regulating services
Wetlands regulate several important ecosystem processes.
Three regulating services are globally signi cant (Greeson et al.
1979), namely water quality improvement, ood abatement, and
carbon management. Wetlands purify water (which is why they
are often called ‘nature’s kidneys’) through storing nutrients
and other pollutants in their soils and vegetation, and trapping
sediments (Ramsar 2009c). In particular, nutrients such as phos-
phorus and nitrogen (as nitrate NO3
), commonly associated with
agricultural runoff and sewage ef uent, are removed or signi -
cantly reduced by wetlands (Fisher and Acreman 1999; Tanner
and Sukias 2011). Nutrient removal ef ciency varies depending
FIGURE 2 Historical and
2003 extent of wetlands in
New Zealand (from Ausseil
et al. 2011b).
river engineering in stopbanks) creates an investment trap in the
long-term (i.e. the maintenance costs increase over time). A more
cost effective option long term would be to restore the natural
wetlands to improve long-term sustainability of the system.
Wetlands play an increasingly recognised role as climate
regulators and in sequestering and storing carbon (Frolking and
Roulet 2007). Healthy, intact peatlands retain signi cant amounts
of carbon as peat, whereas drainage, peat extraction and burning
release it into the atmosphere in the form of greenhouse gases.
The United Nations Intergovernmental Panel on Climate Change
(IPCC) has concluded there is strong scienti c agreement that
the warming of the Earth’s climate since the mid-20th century is
caused by rising levels of greenhouse gases due to human activity,
including peatland drainage. However, wetlands can function as
a climate-change ‘safety net’ to mitigate climate change impacts
provided they are protected, maintained and restored on a global
scale (Ramsar 2009h).
In New Zealand, a recently released report on climate change
(Of ce of the Chief Science Advisor 2013) predicts rising sea
levels, warmer temperatures, more frequent heavy rains, and
lengthy droughts by 2050. Impacts are likely to be greatest
in vulnerable areas such as those already prone to ooding or
drought, and 1-in-100-year oods will become 1-in-50-year
occurrences by the end of the century. The most ood prone
sites often coincide with historical wetland sites, as evidenced by
the extensive ooding in the Bay of Plenty in 2004 (Figure 3;
Gerbeaux 2005).
on the position of the wetland in the catchment. Those in lower
parts of catchments, with large contributing areas, are more ef -
cient at removing nitrogen, while wetlands in upper reaches,
below small contributing areas where surface waters are gener-
ated, are most effective for removing phosphorus (Tomer et al.
2009). All wetlands help prevent nutrients from reaching toxic
levels in groundwater used for drinking purposes and reduce the
risk of eutrophication of aquatic ecosystems further downstream.
Wetlands are natural frontline defences against catastrophic
weather events, providing a physical barrier to slow the speed
and reduce the height and force of oodwaters (Ramsar 2009a,
b). The roots of wetland plants bind the shoreline or wetland–
water boundary to resist erosion. Wetlands have the capacity to
reduce ood peak magnitude by acting as natural reservoirs that
can receive volumes of oodwater, and also regulate water ow
by slowly releasing ood water to downstream areas (Campbell
and Jackson 2004). Where protective wetlands have been lost,
ood damage can be signi cantly worsened, as in Louisiana,
USA, in 2005 when Hurricane Katrina caused major loss of life
and livelihood. Floodplains are known to be critical in mitigating
ood damage, as they store large quantities of water, thereby
reducing the risk of ooding downstream (Zedler and Kercher
2005). It has been estimated that 3–7% of a river catchment area
in temperate zones should be retained as wetlands to provide
adequate ood control and maintain water quality (Mitsch and
Gosselink 2000b). In New Zealand, van den Belt et al. (2013)
developed a dynamic model to simulate ood protection of the
Manawatu River. They suggest that built capital (i.e. man-made
FIGURE 3 Extent of 2004 ooding in Bay of Plenty, New Zealand, compared with historical wetland areas (from Gerbeaux 2005).
Habitat services (or ‘supporting services’)
Habitat services, for example lifecycle maintenance (nursery
service) and gene pool protection, are necessary for sustaining
vital ecosystem functions and the production of all other
ecosystem services. They differ from provisioning, regulating,
and cultural services in that their impacts on people and soci-
eties are often indirect or occur over long time frames, whereas
changes in other categories have relatively direct and short-term
impacts (TEEB 2013).
Although wetlands cover a relatively small area of the Earth’s
surface, they are strongholds of biodiversity. Many are extremely
rich in ora and fauna, several have endemic species, and virtu-
ally all contain species con ned to wetlands. However, as a
result of ongoing land conversion and excessive water abstrac-
tion, wetland species are declining faster than those from other
ecosystems (Ramsar 2009d). In New Zealand, wetlands are one
of the most nationally threatened and degraded ecosystem types
(Ausseil et al. 2011b). Covering only 250 000 hectares (0.93% of
New Zealand’s land area), they support a disproportionately high
number of threatened plants and animals, including 67% of fresh-
water and estuarine sh species (Allibone et al. 2010) and 13%
of nationally threatened plant species (de Lange et al. 2009). In
some regions (e.g. Canterbury), a larger proportion of threatened
plants is associated with wetlands compared with many other
habitats. Wetland biodiversity throughout the world supports
many economic activities, providing people with countless prod-
ucts that are harvested, bought, sold, and bartered. Safeguarding
the variety of life in different types of wetlands across the globe is
therefore a vital part of humanity’s insurance policy for a sustain-
able future (Ramsar 2009d).
Cultural services
Wetlands deliver signi cant non-material bene ts such as
cultural, spiritual, aesthetic, and educational values. They also
provide opportunities for recreation and tourism. The wetland
landscapes and wildlife we value today typically result from
complex interactions between people and nature over centuries.
Once these intimate linkages are damaged or destroyed, it is rarely
possible to restore or recreate them. Wetlands also attract diverse
recreational and ecotourism activities, generating signi cant
incomes that bene t local communities and national economies
(Ramsar 2009g), which is particularly true in New Zealand.
Closely allied to the bene ts of wetlands for recreation and well-
being is their educational value. Catering for a variety of needs,
from conventional school-group visits to engagement of the
wider community, an expanding network of wetland education
centres is being established around the world (Ramsar 2009g).
Numerous such centres have been developed in New Zealand
(e.g. at Miranda in the Waikato, Mangarakau Wetland in Tasman,
Travis Wetland in Canterbury, and Sinclair Wetlands in Otago).
Additionally, the active involvement of the community in restora-
tion projects is increasing, providing Green Prescription health
bene ts (
food-and-physical-activity/green-prescriptions, accessed 2013)
along with the more obvious social, educational and biodiversity
rewards (Figure 4).
Wetlands, particularly peat bogs, are important for providing
a historical legacy by preserving remains of great archaeological
signi cance (Ramsar 2009f). The cold, water-logged and oxygen-
free conditions protect organic materials from decomposing by
inhibiting the growth of bacteria. Perhaps the most fascinating
archaeological remains are the well-preserved Iron Age bog bodies
from north-west Europe (e.g. Tollund Man from Denmark) and
the United Kingdom (Lindow Man (‘Pete Marsh’) from England)
+Europe#Bog Bodies). These human remains provide detailed
evidence on the physical features, clothing, diet and culture of bog
people societies that existed more than 2000 years ago. The study
of other archaeological remains such as pollen grains and macro-
fossils preserved in the peat has enabled detailed reconstruction
of past vegetation and climate to be developed (e.g. McGlone and
Topping 1977; McGlone and Wilmshurst 1999; McGlone 2009).
In New Zealand, podocarp forests that existed c. 2000 years ago,
buried and preserved in wetlands by the Taupo eruption, have
yielded wood, invertebrates, foliage, and branches with attached
seeds, which have enabled forest ‘reconstructions’ and pinpointed
a late summer – early autumn timing for the eruption (Clarkson
et al. 1988, 1992, 1995). In total, 177 wetland archaeological sites
have been inventoried in New Zealand (Gumbley et al. 2005).
New Zealand Māori greatly value wetlands for their spiri-
tual signi cance. They regard wetlands and associated inland
waterways as taonga (treasures, of signi cant value) closely
linked to their identity as tangata whenua (people of the land).
Many wetlands have historical and cultural importance, and
some include wahi tapu (sacred places) (Harmsworth 2002).
Early Māori also used wetlands to hide their precious taonga, for
preserving timber artefacts and waka (canoe), and as a safe haven
in times of war (Gumbley et al. 2005). Common Māori words
for describing a wetland include repo (swamp, bog, marsh) and
ngaere (swamp, wetland) (Harmsworth 2002).
An economic evaluation of the value of New Zealand ecosys-
tems (Cole and Patterson 1997; Patterson and Cole 1999, 2013),
based on Costanza et al.’s (1997) landmark valuation study of
global ecosystems, estimated that inland (freshwater) wetlands
delivered a total value ($2012) of NZ$5,122 million per year. Even
though wetlands cover less than 1% of New Zealand’s land area,
they generate 13% of the direct (i.e. commodities) and indirect
use value (i.e. from supporting or protecting direct value) derived
from land-based ecosystems. Although the most important
ecosystem service was water regulation (storage and retention),
estimated at NZ$3,403 million, Patterson and Cole (2013) noted
that this may be an overestimate for the New Zealand situation
FIGURE 4 Mangaiti Gully, a city council community wetland restoration
project in Hamilton City, North Island, New Zealand.
as we have relatively abundant water supply. Disturbance regula-
tion was the next most important ecosystem service, valued at
NZ$3,242 million, and included storm protection, ood control,
drought recovery and other aspects of habitat response to envi-
ronmental variability. Cultural services (aesthetic, education,
scienti c values) were also high at NZ$787 million, followed
by waste treatment at NZ$743 million. As wetlands cover only
a small portion of New Zealand, Patterson and Cole (2013)
calculated a very high ecosystem service delivery of NZ$52,530
ha–1 yr–1 ($2012; gross direct and indirect use-value1 ) (Table 1). In
a local study, van den Belt et al. (2009) updated the values of
ecosystems in the Manawatu-Wanganui Region (Table 1). Direct
and indirect values were assessed, excluding non-use value
(existence or passive) for lack of data. Wetlands had the highest
annual per-hectare value (NZ$2006) by far ($43,320), mainly due
to their indirect value (in comparison, dairy was $1,7961,2, sheep
and beef $719, native forest $2,065, and horticulture $19,001). In
proportion, wetland service values from freshwater supply and
moderation of extreme events in the region were much higher
than global gures (de Groot et al. 2012; TEEB 2013). However,
several data, methodological and theoretical issues remain to
be resolved (van den Belt et al. 2009; Patterson and Cole 2013)
Nevertheless, monetary valuation of ecosystem services intends
to make both direct and indirect use value visible to policymakers
and the general public. For instance, indirect value was shown to
account for 80% of the total value of ecosystem services in the
Manawatu-Wanganui Region (van den Belt et al. 2009).
As there is increasing interest among decision-makers and
managers in valuing natural capital, we include below two case
studies for contrasting wetland types illustrating the range of
ecosystem services present in New Zealand wetlands.
Whangamarino Wetland
Whangamarino Wetland probably provides the most detailed
economic evaluation of a New Zealand wetland to date (Waugh
2007). This is a large complex of bog, fen, swamp and open water
associated with rivers and streams draining via the Whangamarino
River into the lower Waikato River, midway between Hamilton
and Auckland (Figure 5). It covers an area of 7290 hectares, a
5690-hectare portion of which is administered (since 1989) by
the Department of Conservation and designated as an interna-
tionally signi cant Ramsar site (Department of Conservation
2007). The wetland supports a wide range of economic values,
both use (direct use of a wetland’s goods) and non-use (existence
or passive value), totalling US$20039.9 million per year (Kirkland
1988 in Schuyt and Brander 2004). Of this, more than $7.2 million
was categorised as non-use preservation value in recognition of
society’s willingness to pay for its conservation and sustainable
The wetland complex has a high diversity of habitats and
species. It is home to several threatened plant species including
the swamp helmet orchid Anzybas carseii, which is found only at
Whangamarino, as well as the more widely distributed water milfoil
Myriophyllum robustum, fern Cyclosorus interruptus, bladder-
wort Utricularia delicatula, clubmoss Lycopodiella serpentina,
and liverwort Goebelobryum unguiculatum. Whangamarino
provides habitat for one- fth of New Zealand’s population of
Australasian bittern (Botaurus poiciloptilus), as well as other
threatened birds such as the grey teal (Anas gibberfrons), spot-
less crake (Porzana tauensis plumbea) and North Island fernbird
(Bowdleria punctata vealeae). The wetland contains a key popu-
lation of the threatened black mud sh (Neochanna diversus),
which survive dry periods by burying themselves in moist mud or
under logs until the water returns. In 1994, construction of a rock
rubble weir was commissioned on the Whangamarino River to
increase minimum water levels and reinstate a ‘wet/dry’ seasonal
cycle (Department of Conservation
whangamarino/ramsar-site/ accessed 2013). This became fully
functional in 2011 and now provides improved hydrological
regimes to over 2000 hectares of wetland.
The main use values recognised for Whangamarino Wetland
are ood control, gamebird hunting, recreation, commercial
shing of eels (tuna), and carbon storage. Of increasing economic
signi cance is the wetland’s role as part of the substantial ood
control scheme on the lower Waikato River (Waugh 2007), which
lowered regional water levels. The scheme reproduces the natural
water storage function of Whangamarino Wetland and adjoining
Lake Waikare, but in a more controlled way, to depress ood
peaks in the Waikato River (Department of Conservation 2007).
Water storage in the wetland has reduced public works costs (e.g.
stopbank construction), and damage to farmland during the 10
ood events that occurred between 1995 and 1998, saving an
estimated NZ$5.2 million in ood control costs during a single
1-in-100-year ood event in 1998 (Waugh 2007).
Gamebird hunting is another important use of Whangamarino
Wetland, particularly in the c.1600 hectares under private tenure.
The wetland is visited by most New Zealand gamebird species at
least seasonally and these include mallard (Anas platyrhynchos),
grey duck (Anas superciliosa superciliosa), New Zealand shov-
eller (Anas rhynchotis variegata), pūkeko (Porphyrio porphyrio),
black swan (Cygnus atratus), paradise shelduck (Tadorna varie-
gata), and Canada goose (Branta canadensis). The Gamebird
Habitat Trust raises more than NZ$60,000 per year from gamebird
habitat stamp fees at $2 per hunting licence to support restora-
tion of wetland sites, including Whangamarino (Department of
Conservation 2007).
Torehape Bog
Torehape Bog on the Hauraki Plains, North Island, provides
a rare example of an attempt to harvest peat sustainably for the
horticultural industry without compromising biodiversity values.
The overall project is a partnership between mining companies,
FIGURE 5 Aerial view of Whangamarino Wetland, North Island,
New Zealand. (Photo: Shonagh Lindsay)
research scientists, land managers, regulatory authorities, NGOs,
and community groups.
Torehape comprises 180 hectares of privately owned bog,
which is currently being mined for horticultural peat, adjoining
350 hectares of Wetland Management Reserve administered by
the Department of Conservation. The restiad raised bog is domi-
nated by Sporadanthus ferrugineus, and is a rare and threatened
ecosystem (Williams et al. 2008) reduced to three natural sites
in the Waikato Region. Gamman Mining has resource consent
to mine the top metre of a 4–6 metre depth of peat on private
land, and are required to restore the bare surface to original bog
vegetation. Torehape Peat Mine produced c. 60 000 cubic metres
in 2013 (down from a peak of 80 000 m3 yr–1 in the 1990s), which
equates to c. NZ$3.4 million annually (R. Gamman, pers. comm.,
2013). The peat is used for potting mixes, compost, mushroom-
growing media, organic fertilisers, and soil conditioners.
A patch approach to restoration (Figure 6) has been devel-
oped following peat harvesting whereby small ‘islands’ of milled
peat scattered over the mine surface are seeded with early succes-
sional mānuka. The developing mānuka shrubland functions as
a nurse, providing suitable environmental conditions for seeds
and propagules of later successional bog species (Sporadanthus,
Empodisma robustum, Sphagnum cristatum) that are blown in
from the adjoining intact peatland.
Non-use values of Torehape Mine relate to the status of the
site as a threatened ecosystem type, and its habitat values for
threatened plants such as Sporadanthus, Calochilis robertsonii
and Dianella haematica, birds such as the Australasian bittern
and North Island fernbird, and the stem borer caterpillar ‘Fred the
Thread’ (Houdinia exilissima).
The restoration project has provided plant and invertebrate
source material, and techniques for the successful establishment
of three new populations of restiad bog at sites where the bog
type originally occurred (Lake Serpentine, Lake Komakorau,
Waiwhakareke Natural Heritage Park). These populations are
important for educational purposes, with the Lake Serpentine
one being showcased within a predator-proof fence as part of
the proposed National Wetland Trust interpretation centre (http://, accessed 4 September
Wetlands have the highest carbon density among terrestrial
ecosystems and contain 20–25% of the world’s organic soil
carbon (Gorham 1991). They are the dominant natural source of
methane emissions (Kayranli et al. 2010), but can also sequester
carbon as anaerobic conditions prevent decomposition of organic
matter. Their contribution as a source and sink of carbon is a major
issue in evaluating climate change impacts (UNFCCC 1997).
When overall carbon dynamics of these systems are considered,
wetland ecosystems compare favourably with other terrestrial
habitats (Anderson-Teixeira and DeLucia 2011). Freshwater
wetlands can be broadly divided into peatlands and mineral soil
wetlands – known as freshwater mineral soil (FWMS) wetlands
(Bridgham et al. 2006). In peatlands, carbon is mainly seques-
tered through organic matter production and accumulation,
which outweighs organic matter decomposition in anaerobic
soil conditions (Grover et al. 2012). In FWMS wetlands, carbon
FIGURE 6 Patch approach to restoration whereby the islands provide a seed source for surrounding bare mined surface: A, 0 years (set-up with milled peat
and mānuka branches laden with seed capsules); B, after 1.5 years (mānuka (Leptospermum scoparium) has established); C, after 3.4 years (Sporadanthus
has established around islands, Baumea teretifolia on mine surface); D, after 6 years (revegetated, Sporadanthus owering left foreground).
sequestration occurs through sediment deposition from upstream
as well as on-site plant production; together these outweigh the
decomposition rates (Bridgham et al. 2006). Net carbon release
versus carbon sequestration changes over time (Mitra et al. 2005;
Kayranli et al. 2010). On a longer-term scale (>500 years) and
on a global scale, carbon sequestration from wetlands has been
shown to be greater than carbon release, creating a net cooling
effect (Whiting and Chanton 2001; Frolking and Roulet 2007).
Land-use change has had a major impact on wetland carbon
storage and dynamics. Wetland drainage and subsequent conver-
sion to agriculture or forestry results in substantially increased
decomposition rates of organic matter previously stored under
anaerobic conditions, and signi cant amounts of carbon released
into the atmosphere (Mitra et al. 2005). The rates of organic
matter decomposition from wetlands converted to other land
uses also vary with wetland and peat types (Zauft et al. 2010).
Peatlands converted to other land uses show higher decomposi-
tion rates and therefore higher carbon loss compared with FWMS
wetlands, which may lose negligible amounts of carbon as a
result of land-use change, as reported for the wetlands of North
America (Bridgham et al. 2006).
Ausseil et al. (in prep.) summarises information on carbon
stocks in New Zealand garnered from eld survey. It is estimated
that 36 Tg of carbon is stored in the upper 30 cm of wetland soils,
rising to 164 Tg if the full peat pro le is considered. Carbon densi-
ties range between around 1,600 tC ha–1 under organic soils and
around 200 tC ha–1 under FWMS soils. These values are compa-
rable with freshwater wetlands in the US and Canada. Draining
for agricultural use increased mineralisation and caused an
increase in net carbon emission. Emission estimates vary greatly,
from 1 tC ha–1yr–1 at a New Zealand site (Nieveen et al. 2005) to
30 tC ha–1yr–1 in Scandinavia (Kasimir-Klemedtsson et al. 1997).
Freshwater wetlands in New Zealand have been severely
degraded by anthropogenic activities since pre-European settle-
ment. As they are ecotones that support both terrestrial and
aquatic biota, they can be affected by a range of human distur-
bances, including alterations of nutrient supply, changes in
hydrology, sedimentation, re, vegetation clearance, soil distur-
bance, weed invasions (aquatic and terrestrial), and animal pest
invasions (e.g. livestock grazing, pest sh, mustelids, or rodents)
(Clarkson et al. 2004c). Human disturbances can change biolog-
ical community structure, composition, and function, thereby
altering ecological processes. Degradation of this suite of ecolog-
ical features is described as a decline in ecological integrity,
which then affects functions and services. Ausseil et al. (2011a)
developed six measures of anthropogenic pressures known to
impact wetland ecological integrity: naturalness of the upper
catchment cover; arti cial impervious cover; nutrient enrichment;
introduced sh; woody weeds; and drainage. These measures
were chosen because they covered the major threats known to
damage wetlands (Brinson and Malvarez 2002; Clarkson et al.
2004c; Sorrell et al. 2004), and could be measured consistently
using geographic information system (GIS) indicators at national
level. Transfer functions were then applied to re ect possible
impacts on ecological integrity. The potential impacts were then
integrated into a single index of ecological integrity to quantify
potential human disturbance. The index ranged from 1 (pristine)
to 0, where 0 indicates complete loss of biodiversity and associ-
ated ecological function.
Using this approach, ecological integrity in over 60% of
wetlands was measured at less than 0.5. These results indicate
high levels of human-induced disturbance pressure and prob-
able substantial biodiversity loss. Values re ect general patterns
of agricultural and urban development with the lowest measures
found in biogeographic units characterised by warm, at, fertile
land favoured for agricultural development. For example, the
Waikato Region is dominated by intensive agriculture and
contains wetlands with a mean ecological integrity of 0.35. In
contrast, wetlands in Fiordland or Stewart Island that are predom-
inantly managed as national parks have typically high ecological
integrity indices at over 0.9. Ausseil et al. (2011b) have combined
ecological integrity with historical extent to develop a habitat
provision index for wetlands. The degree of habitat provision
varies per biogeographic unit in New Zealand (Figure 7). Low
values represent units where wetland areas either are small,
depleted or have been degraded.
The ecological condition of wetlands can also be assessed in
the eld using the Wetland Condition Index (WCI), a semi-quan-
titative metric developed for state of the environment monitoring
(Clarkson et al. 2004c). Five ecological indicators are compared
and scored against an assumed natural state (as at c. 1840):
hydrological integrity; physiochemical parameters; ecosystem
intactness; browsing, predation and harvesting (animal impacts);
and dominance of native plants. The total score is out of 25; the
higher the score, the better the ecological condition. Wetlands
in developed, agricultural catchments have signi cantly lower
WCI than wetlands in indigenous-dominated catchments (n
= 72, P < 0.001; Figure 8). The WCI measures actual change
(state) compared with predicted change, using the GIS-based
wetland ecological integrity metric but requires eld visits to
individual wetlands, whereas the GIS approach provides full
national coverage. Comparison of scores of signi cant wetlands
FIGURE 7 Wetland habitat provision index for New Zealand per biogeo-
graphic unit (from Ausseil et al. 2011b).
at the regional scale (e.g. West Coast) indicates the measures are
highly correlated. Ongoing eld checking of wetlands in targeted
regions (e.g. Southland and Auckland) is currently underway to
re ne and verify the data in Ausseil et al. (2011a) to increase the
usability of the GIS approach.
The Whangamarino and Torehape case studies above have
demonstrated the values associated with restoring wetlands.
Restoration of degraded wetlands around the world is vital to
maintain biodiversity and associated ecosystem services. In a
study in the Mississippi Valley, for instance, the value of restoring
forested wetland was assessed on three ecosystem services
(greenhouse gas mitigation, nitrogen mitigation, and waterfowl
habitat), showing that a return in restoration investment could be
achieved in 2 years (Jenkins et al. 2010). The success of wetland
restoration, however, is variable. Wetlands, particularly the late-
successional fens and bogs, are complex and dif cult to restore.
In general, once disturbed, ecosystem recovery is slow or trends
towards alternative states that differ from reference sites and
may require costly intervention. In a global analysis of wetland
restoration projects, large wetland areas (>100 ha) and wetlands
restored in warm (temperate and tropical) climates recovered
more rapidly than smaller wetlands and wetlands restored in cold
climates (Moreno-Mateos et al. 2012). Balmford et al. (2002)
concluded many wetlands have been modi ed for short-term
private bene ts, for example intensive agriculture or shrimp
farming, that do not factor in extensive losses of social and other
bene ts. The authors present a strong economic case for retaining
natural wetland habitats because, in all studies analysed, devel-
oped wetlands have a much lower dollar value than that of natural
In New Zealand, most of the wetlands that have survived the
human settlement phase are modi ed to some degree, particularly
those remnants in agricultural landscapes or urban environments.
As awareness of wetland values spreads, the demand for tech-
nical resources has increased (e.g. Peters and Clarkson 2010;
Denyer and Peters 2012). The number of private individuals,
community groups, iwi, and organisations restoring wetlands
is rapidly increasing. General public recognition of wetland
values is also expanding, for example, a survey of Hawke’s
Bay households indicated the net non-market value of a resto-
ration programme at Pekapeka Swamp to be NZ$5–$18 million
(Ndebele 2009). Regional councils also have a mandate to
protect wetlands and have developed environmental fund initia-
tives (Waikato Regional Council: http://www.waikatoregion.govt.
and plans to strengthen protection of remaining wetlands
(Lambie 2008; Otago Regional Council 2012). However, we
cannot be complacent, as wetlands continue to degrade and
disappear and many require active management to enhance their
long-term viability. Only continuing awareness of wetland threats
and ongoing commitment of funds for protection and restoration
will ensure the multiple values of our wetlands are preserved for
future generations.
We thank Bruce Clarkson and Bill Lee for commenting on
the text. This research was supported by Core funding for Crown
Research Institutes from the Ministry of Business, Innovation
and Employment (MBIE)’s Science and Innovation Group, and
MBIE contract CO9X1002.
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1 Patterson and Cole (2013) distinguish gross value (including
supporting value) from net value (without supporting value) to avoid
2 Based on more recent calculations using a unit price for milk solids of
NZ$6 and a pastoral pressure of 3.5 cows per hectare with each cow
producing 400 kg of milk solids per season, the gure would increase to
NZ$8,400 in 2013.
... Table 2. Examples of Ecosystem Services provided by restored wetlands (RW). Based on Ecosystem Services categories of the Millennium Ecosystem Assessment as applied to wetlands [4,66,67]. ...
... Table 3. Examples of Ecosystem Services provided by integrated constructed wetlands (ICW). Based on Ecosystem Services categories of the Millennium Ecosystem Assessment as applied to wetlands [4,66,67]. ...
... Idealized Ecosystem Services of Ecosystem Services provided by constructed wetlands (CW) for wastewater treatment, restored wetlands (RW), and integrated constructed wetlands (ICW). Based on Ecosystem Services categories of the Millennium Ecosystem Assessment as applied to wetlands[4,66,67]. ...
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In response to the global loss and degradation of wetland ecosystems, extensive efforts have been made to reestablish wetland habitat and function in landscapes where they once existed. The reintroduction of wetland ecosystem services has largely occurred in two categories: constructed wetlands (CW) for wastewater treatment, and restored wetlands (RW) for the renewal or creation of multiple ecosystem services. This is the first review to compare the objectives, design, performance, and management of CW and RW, and to assess the status of efforts to combine CW and RW as Integrated Constructed Wetlands (ICW). These wetland systems are assessed for their ecological attributes and their relative contribution to ecosystem services. CW are designed to process a wide variety of wastewaters using surface, subsurface, or hybrid treatment systems. Designed and maintained within narrow hydrologic parameters, CW can be highly effective at contaminant transformation, remediation, and sequestration. The ecosystem services provided by CW are limited by their status as high-stress, successionally arrested systems with low landscape connectivity and an effective lifespan. RW are typically situated and designed for a greater degree of connection with regional ecosystems. After construction, revegetation, and early successional management, RW are intended as self-maintaining ecosystems. This affords RW a broader range of ecosystem services than CW, though RW system performance can be highly variable and subject to invasive species and landscape-level stressors. Where the spatial and biogeochemical contexts are favorable, ICW present the opportunity to couple CW and RW functions, thereby enhancing the replacement of wetland services on the landscape.
... Wetlands, which have the richest biodiversity after rainforests, contain 40% of all species and 12% of all animal species in the world [2]. Wetlands, where biodiversity and production are much higher than terrestrial areas, provide important ecosystem services for the sustainability of the ecosystem [3]. Wetlands, one of the world's most productive and valuable ecosystems, provide a wide variety of economic, social, environmental and cultural benefits [4]. ...
... Based on this interest of human beings in bird species; we can use bird watching in raising awareness of nature, creating awareness of ecosystems, monitoring and protecting wetlands. Conservation and restoration of wetlands is essential for the future sustainability of the planet, and provides safety nets for emerging issues such as global climate change, food production for the growing world population, disturbance regulation, clean water and the general well-being of society [3]. ...
... Conservation and restoration of wetlands is essential for sustainability and provides safety nets for emerging issues such as global climate change, food production for a growing world population, clean water, and the general well-being of society [3]. One of the primary steps in raising awareness of nature conservation in sensitive ecosystems such as wetlands is to raise awareness in society. ...
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Wetland losses and pollution in water resources, which are increasing on a global scale, affect biodiversity and sustainable ecosystem structure. The most important trigger of this extinction, which will cause wide-ranging ecological problems, is human activities, and necessary steps must be taken quickly to protect its viability. In the study, it was aimed to develop a measurement tool that measures the awareness level of children about wetlands in a valid and reliable way. In the descriptive study, data were obtained from three different groups. Participants consist of secondary school students between the ages of 9-15 studying in Turkey. Explanatory factor analysis was performed by applying the 26-item candidate scale questions to 245 secondary school students. Then, confirmatory factor analyzes were carried out with the data obtained from the participation of 201 students. SPSS 26.0 and AMOS statistical software were used in the analysis of the data. Evaluations of secondary school students' awareness of wetlands were examined on a group of 446 people. As a result of the validity analyzes made with the data obtained from the application, it was determined that the scale consisted of 14 items with two factors. This structure was confirmed by confirmatory factor analysis. The reliability value of the entire scale was 0.891; 0.704 for the wetland awareness factor in terms of bird species diversity; The importance of wetlands and the awareness of the problems experienced factor ÖZET Küresel ölçekte giderek artan sulak alan kayıpları ve su kaynaklarındaki kirlilik, biyoçeşitliliği ve sürdürülebilir ekosistem yapısını etkilemektedir. Geniş çaplı ekolojik sorunlara neden olacak bu yok oluşun en önemli tetikleyicisi ise insan faaliyetleridir ve sürdürülebilirliğin korunması konusunda gerekli adımların hızla atılması gerekmektedir. Doğa koruma bilincinin oluşturulmasında bütüncül bir yaklaşım gerekmektedir ve atılacak öncelikli adımlardan biri toplumda farkındalık yaratmaktır. Farkındalık, bir canlının çevresinde gelişen olayları bilme, algılama ve duyumsama becerisi olarak tanımlanmaktadır. Yapılan çalışmada çocukların sulak alanlar ile ilgili farkındalık düzeylerini ölçen bir ölçek geliştirilmesi amaçlanmıştır. Betimsel olarak yapılandırılan araştırmada veri toplama aracı olarak geliştirilen aday ölçek maddeleri araştırmacılar tarafından hazırlanmış ve uzman görüşleri doğrultusunda oluşturulmuştur. Katılımcılar, Türkiyede öğrenim gören 9-15 yaş arasındaki ortaokul öğrencilerden oluşmaktadır. 26 maddelik aday ölçek soruları 245 ortaokul öğrencisine uygulanarak açıklayıcı faktör analizi yapılmıştır. Daha sonra 201 öğrencinin katılımından elde edilen verilerle doğrulayıcı faktör analizleri gerçekleştirilmiştir. Verilerin analizinde SPSS 26.0 ve AMOS istatistik yazılımı kullanılmıştır. Ortaokul öğrencilerinin sulak alanlara yönelik farkındalıklarının değerlendirmeleri ise 446 katılımcıdan elde edilen verilerle gerçekleştirilmiştir. Yapılan ilk uygulamadan elde edilen verilerle yapılan geçerlik analizleri sonucunda ölçeğin iki faktörlü 14 maddeden oluşan bir ölçek olduğu tespit edilmiştir. Bu yapı doğrulayıcı faktör analizi ile doğrulanmıştır. Ölçeğin tamamının güvenirlik değeri 0,891; kuş tür çeşitliliği açısından sulak alan farkındalığı faktörü için 0,704; Sulak alanların önemi ve yaşanan sorunlar farkındalığı faktörü için 0,895 olduğu belirlenmiştir. Yapılan örnek uygulamada cinsiyet, yaş ve daha önce sulak alanlarla ilgili ders almaları ile sulak alan farkındalığı arasında anlamlı bir fark bulunmamıştır (p: >0,05). Daha önce yaşadığı bölgedeki bir sulak alana gidip gitmemeleri ile çocukların sulak alan farkındalıkları arasında ise anlamlı bir fark olduğu tespit edilmiştir (U=15052,5 ve p: <0,05). Daha önce sulak alanlara giden öğrencilerde sulak alan farkındalığının daha yüksek olduğu bulunmuştur. Ortaokul öğrencileri ile gerçekleştirililen bu araştırmada yer alan katılımcılar bağlamında bu sonuçlara göre geliştirilen ölçeğin çocukların sulak alan farkındalık düzeylerini geçerli ve güvenilir biçimde ölçtüğü sonucuna ulaşılmıştır.
... Thus, loss of a species could lead to weakening of the functioning of the ecosystem. Wetlands are described as lands transitional between terrestrial and aquatic systems where an oversupply of water for all or part of the year results in distinct wetland communities (Clarkson et al, 2013). In addition, they also carry out services like regulating atmospheric gases, sequestering carbon, protecting shorelines, sustaining unique indigenous biota, and providing cultural, recreational and educational resources (Dise, 2009). ...
... In addition, they also carry out services like regulating atmospheric gases, sequestering carbon, protecting shorelines, sustaining unique indigenous biota, and providing cultural, recreational and educational resources (Dise, 2009). Wetlands of different countries in the world are disappearing under increasing pressure from human activities and hence, require urgent remediation if their associated ecosystem services are to be maintained (Clarkson et al., 2013). ...
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The wetland ecosystem, aptly named as the Gene Park, Sherubtse College, is the hub of various life forms. In general wetlands provide numerous ecosystem services such as acting as natural filters of water and pollutants, preserving water, slowing erosion and supporting a wide diversity of plants and animals life. Thus, the species diversity of vascular plants in the area was measured using different biodiversity indices. A total number of 123 vascular plant species were recorded from the study area. The species richness indicated a high index of 1.6; dominance value was 0.937 for few species like Equisetum diffusum D. Don, Pilea pumila (L) A. Gray, Aconogonum molle (D. Don) H. Hara and Schima khasiana Dyer. Species diversity value was 3.5 indicating rich biodiversity, but species distribution was not uniform (0.19), similarity index (0.26) indicated distinct species composition in the wetland and terrestrial area of the gene park
... Different literature showed that 50%-75% of peatlands had been drained for various land use purposes worldwide since 1900 (Clarkson et al., 2013;Bess et al., 2014;Lamers et al., 2015;Chimner et al., 2017). As a result, peatland drainage has contributed to losing ecosystems services such as regulating water quality and supply, carbon storage, biodiversity, recreation, knowledge archives, cultural heritage, flood-water regulation, sediments, and nutrients trapping (Clarkson et al., 2013;Tomscha et al., 2021). ...
... Different literature showed that 50%-75% of peatlands had been drained for various land use purposes worldwide since 1900 (Clarkson et al., 2013;Bess et al., 2014;Lamers et al., 2015;Chimner et al., 2017). As a result, peatland drainage has contributed to losing ecosystems services such as regulating water quality and supply, carbon storage, biodiversity, recreation, knowledge archives, cultural heritage, flood-water regulation, sediments, and nutrients trapping (Clarkson et al., 2013;Tomscha et al., 2021). Restoring of degraded and rewetting of drained peatlands have been practiced for the last 25 years in North America and Europe, where 85% of the 4 million km 2 global peatlands are currently located (Lamers et al., 2015;Chimner et al., 2017;Andersen et al., 2017;Peters and von Unger, 2017). ...
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Drained peatlands have been rewetted for restoration in Europe and North America for about 25 years. However, information on spatial variability of soil chemical and biochemical properties in long-term drained and restored peatlands is insufficient to design appropriate research methods and soil sampling protocols for monitoring biogeochemical processes. The study aimed to examine the influence of long-term drainage and rewetting of peatlands on smallscale spatial variability of the soil chemical properties and enzyme activities. We collected 400 soil samples from the 0-15 cm and 15-30 cm soil depths of a drained and a corresponding rewetted peatland. The number of grid cells was 100 for each of the drained and the rewetted peatland, and the size of each grid cell was 3 m × 3 m. We analyzed 17 soil parameters from the surfaces and 14 from the subsurface of both sites. The variability (range, SD, and CV) of all the soil properties was higher in the drained peatland than in the restored peatlands except for the soil pH. The geostatistical analysis revealed only the soil pH, acid phosphatase, β-glucosidase, and arylsulfatase activities disclosed the strong spatial dependency at the ≤5 m semivariance range in the drained peatland. However, more than 80% of the soil properties showed a strong spatial dependence within the 4-20 m semivariance ranges in the restored peatland. The strong spatial dependencies of all the soil properties in the long-term restored peatland conclusively call for the spatial soil sampling and geostatistical data analysis methods to capture substantial spatial variability that has important implications in degraded peatland restoration.
... itical ecological functions and services, ranging from flood control to groundwater recharge and discharge, water quality maintenance, habitat and nursery for diverse plant and animal species, soil components, carbon sequestration, and other life support functions (Barbier et al. 1997; Davies and Day 1998;Birol et al. 2006;Whiteoak and Binney 2012;Clarkson et at. 2013). Despite their importance, approximately 50% of the world's wetlands have been lost in the last ~ 100 years (Finlayson 2012;Davidson 2014;Dalu et al. 2017). ...
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Wetlands are amongst the world’s most important ecosystems, providing direct and indirect benefits to local communities. However, wetlands worldwide continue to be degraded due to unsustainable use and improper resource management. In this paper, we assess the perceptions, importance, management and utilisation of wetlands among local community members using a household questionnaire and field observations within the seven Thulamela municipality wetlands, Vhembe Biosphere Reserve in South Africa. Seven wetlands were chosen for the study, with 140 household respondents randomly selected for a questionnaire survey. The study indicated that wetlands were beneficial in supporting local communities through resource provisioning. The unemployment rate and household respondents’ income were the main contributors to increased wetland dependency and utilisation. We found that urban and rural developments, unregulated use and extensive agricultural practices (i.e., cultivation, livestock grazing) have resulted in wetland degradation. We observed that the local communities around the wetlands were interested in the benefits they receive from wetlands when compared to their conservation. Furthermore, the study observed poor wetland co-management or collaboration among the local stakeholders. This has resulted in a lack of openly known, active platforms to discuss wetlands management issues. These results highlight that centralized, top–down approaches to wetland use are insufficient for maintaining and managing wetland ecosystems, posing a challenge to sustainable wetland management. Therefore, there is a need to develop a shared understanding through bottom-up approaches to wetland management nested within national regulatory frameworks, ideally combined with awareness building and knowledge sharing on ecological benefits and management of wetlands.
... Human activities have caused significant damage to wetlands [1,2]. Large-scale reduction and functional degradation of wetlands have seriously affected the sustainable development of regions [3][4][5]. ...
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Wetlands are important ecosystems for biodiversity preservation and environmental regulation. However, the integrity of wetland ecosystems has been seriously compromised and damaged due to the reckless and indiscriminate exploitation of wetland resources during economic development by human society. Hence, wetland restoration has now attracted wide attention. Understanding wetland restoration suitability and its relationship with river grade and river distance is an important step in further implementing wetland restoration and ensuring an orderly wetland development and utilization. In this study, wetland restoration suitability is evaluated combining natural and human factors. Taking its result as an important basis, the spatial distribution characteristics of different levels of wetland restoration suitability are discussed for the studied region; the percentage distribution of different levels of wetland restoration suitability is analyzed for 10 km long buffer zones of rivers of different grades, and the association between the distribution of different levels of wetland restoration suitability and the river distance (2, 4, 6, 8, and 10 km) is also analyzed for different buffer zones of rivers in different grades. Our findings show that the spatial distribution of wetland restoration suitability is closely associated with the grade of rivers and the distance of the wetland patches from the river. The higher the river grade, the higher the percentage of the wetland with high restoration suitability within the same river distance. The percentage of wetlands with high restoration suitability has shown a notably decreasing trend as the river distance increases for the areas beside rivers of all grades, while the percentage of a wetland area with relatively high restoration suitability tends to increase as the river distance increases for the areas beside rivers of grade I and II and does not have a noticeable trend to change as the river distance changes for the area beside rivers of other grades. Results of this can provide technical support for wetland restoration suitability evaluation for plain areas, a spatial reference for wetland restoration prioritizing, and an orderly wetland development and utilization in future studies and planning.
... Wetlands play an important role in giving valuable ecosystem services and goods like provisioning, regulating habitat and cultural services. Due to human pressure wetlands are being deprecated, but protection and restoration of wetlands are essential for maintaining the ecosystem balance (Biswas et al. 2012a, b;Biswas et al. 2019;Clarkson et al. 2013). ...
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In this study, the functions and threats of Suraha Tal Wetland are identified by the stated preference method and weightage is given according to their rank. The objective of the study is to determine the total economic value of Suraha Tal Wetland. The direct value can be drawn from the market price and from a survey of the stakeholders. Suraha Tal Wetland is also famous for the presence of the Jai Prakash Narayan Birds Sanctuary, which makes it a biodiversity-enriched area. The indirect value has been drawn from a review of the literature on Suraha Tal Wetland and the relevance of this literature is justified through the comprehensive meta-analysis (CMA) software. The total valuation of the wetland has been calculated. The paper concludes with suggestions for a few management strategies for better wetland management.
... Although, human-wildlife interactions are often reduced to human-wildlife conflicts (SOULSBURY & WHITE, 2015), evidence is growing that biodiversity is also providing psychological benefits by improving human health (FULLER et al., 2007;METHORST et al., 2020). Moreover, ecosystem services and biodiversity may influence human well-being (CLARKSON et al., 2013;DÍAZ et al., 2006;MILLENNIUM ECOSYSTEM ASSESSMENT, 2005). Numerous studies have revealed that species richness of birds and human wellbeing were positively related (DALLIMER et al., 2012;LUCK et al., 2011;SHWARTZ et al., 2014). ...
Algerian cities have experienced rampant urbanization for several years; this growth often occurs at the expense of natural habitats. Here, we present the results of the first census using a questionnaire focused on an urban pond in order to investigate the biodiversity perceptions in local attitudes, knowledge, and values. Our study reveals a general lack of understanding of biodiversity and ecosystem services, which may mislead local citizens to disconnect biodiversity from utilitarian or hedonic values. Furthermore, a large proportion of respondents perceived the wetlands as a nuisance. Equally important, the results among respondents indicate a significant gender bias due to a narrower window of opportunities (education, jobs, etc.) available to women than that which is available to men. The results point to an urgent need to implement policies aimed at inequality reduction and welfare improvement. Our study needs replication across the region, and its results should inform decision-makers in designing relevant policies associated with urban planning, investment in human capital, environmental education in school curricula, and the empowerment of women.
... All these changes, in turn, have had a negative effect on the entire hydrological cycle, as has been observed in the Marne reservoir in northern France [47]. Furthermore, drainage of wetland ecosystems accompanied by intensified eutrophication resulting from agricultural nutrient inputs can lead to degradation of valuable habitats and result in decreased biodiversity [48,49]. The eutrophic status of the studied lakes was proven by using phytoplankton composition. ...
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Phytoplankton is one of the five biological quality elements used in the assessment of the ecological status of surface waters according to the European Water Framework Directive established in 2000. In this study, we determined the ecological status of three small and shallow lakes in the Polesie Plain, Eastern Poland, by using indices based on phytoplankton assemblages. The predominant phytoplankton of all three lakes were filamentous cyanobacteria, both heterocystous and non-heterocystous, represented by the genera Aphanizomenon, Planktothrix, Limnothrix, and Planktolyngbya. We used the Hungarian Q index, German PSI (Phyto-See-Index), and recently developed PMPL (Phytoplankton Metrics for Polish Lakes) for Polish lakes. We compared the results from the calculation of the indices to physicochemical data obtained from the lake water and Carlson’s Trophy State Index (TSI). On the basis of TSI, Gumienek and Glinki lakes were classified as advanced eutrophic, whereas Czarne Lake had a better score and was classified as slightly eutrophic. The trophic state was generally confirmed by the ecological status based on phytoplankton indices and also showed the diverse ecological situation in the lakes studied. Based on the Polish PMPL, Gumienek Lake was classified as having bad status (ecological quality ratio (EQR) = 0.05), whereas Glinki and Czarne lakes were classified within the poor status range (EQR = 0.25 and 0.35, respectively). However, based on the German PSI, the lakes were classified in a different manner: the status of Gumienek and Czarne lakes was better, but unsatisfactory, because they were still below the boundary for the good status category recommended by the European Commission. The best ecological status for the studied lakes was obtained using the Q index: Gumienek Lake with EQR = 0.42 had a moderate status, and Czarne Lake with EQR = 0.62 obtained a good status. However, Glinki Lake, with EQR = 0.40, was classified at the boundary for poor and moderate status. Based on our study, it seems that the best index for ecological status assessment based on phytoplankton that can be used for small lakes is the Polish (PMPL) index.
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In the study, International Waterbird Census (IWC) conducted in 2021 in wetlands with different habitat characteristics around the Dardanelles were evaluated. 3086 individuals belonging to 30 waterbird species were counted in Kavak Delta, 31 species and 1150 individuals in Çardak Lagoon, 22 species and 3906 individuals in Gökçeada Salt Lake, 11 species and 289 individuals in Suvla Salt Lake and 8 species and 84 individuals in Uzunhızırlı Pond. The highest species diversity (Shannon-Wiener Indices, H: 2,473) and the highest species richness (Margalef Index, M: 4,257) were calculated in the Çardak Lagoon. As the number of habitats in the wetland increased, the number of species also increased (p<0.0001). As a result, the data obtained revealed the importance of the wetlands for the winter visitor waterbirds, and pioneering data were presented for the sustainability of the wetlands in future studies. Anahtar Kelimeler
Carbon fixation under wetland anaerobic soil conditions provides unique conditions for long-term storage of carbon into histosols. However, this carbon sequestration process is intimately linked to methane emission from wetlands. The potential contribution of this emitted methane to the greenhouse effect can be mitigated by the removal of atmospheric CO2 and storage into peat. The balance of CH4 and CO2 exchange can provide an index of a wetland's greenhouse gas (carbon) contribution to the atmosphere. Here, we relate the atmospheric global warming potential of methane (GWPM) with annual methane emission/carbon dioxide exchange ratio of wetlands ranging from the boreal zone to the near-subtropics. This relationship permits one to determine the greenhouse carbon balance of wetlands by their contribution to or attenuation of the greenhouse effect via CH4 emission or CO2 sink, respectively. We report annual measurements of the relationship between methane emission and net carbon fixation in three wetland ecosystems. The ratio of methane released to annual net carbon fixed varies from 0.05 to 0.20 on a molar basis. Although these wetlands function as a sink for CO2, the 21.8-fold greater infrared absorptivity of CH4 relative to CO2 (GWPM) over a relatively short time horizon (20 years) would indicate that the release of methane still contributes to the overall greenhouse effect. As GWPM decreases over longer time horizons (100 years), our analyses suggest that the subtropical and temperate wetlands attenuate global warming, and northern wetlands may be perched on the "greenhouse compensation" point. Considering a 500-year time horizon, these wetlands can be regarded as sinks for greenhouse gas warming potential, and thus attenuate the greenhouse warming of the atmosphere.
Mires dominated by restionaceous rushes occur in valley and basin sites around New Zealand. The main restiad species is Empodisma minus which produces a surface mat of negative geotropic roots which eventually form a principal part of the underlying peat. Comparison of the peat chemistry of four such mires with a minerotrophic mire w*as consistent with their suspected ombrotrophic status. The base-exchange capacity achieved (704 + 23.3 mequiv m−2 of the surface) by the superficial roots of Empodisma is at least as great as that of the New Zealand Sphagnum cristatum which is not dominant in ombrotrophic conditions. The widespread development of a hummock and hollow microtopography may be associated with higher rainfall regimes and the propensity of Empodisma for directing most incoming rainfall (on which its nutrient economy depends) down its wiry stems.
A 5-year litterbag study examined decomposition rates at four sites representing restiad peatland succession in Waikato, New Zealand. Early successional sites were dominated by Baumea rubiginosa, or Leptospermum scoparium, mid-successional by Empodisma robustum, and late successional by Sporadanthus ferrugineus. Leaf/culm materials from these species were placed on the surface, and roots of Empodisma and Sporadanthus buried at depths of 5, 25, and 55 cm to test the influence of succession on species and site decomposition rates. Typha latifolia leaves from a Canadian bog were placed at the surface and three depths to allow comparisons with northern peatlands. Litterbags were retrieved after 0.5, 1, 2, 3, 4, and 5 years, and mass remaining characterized by an exponential model k value. Surface litter k values (0.12–0.80 y−1) decreased from early to late successional species; however, decomposition was slower at more waterlogged early successional sites. Buried litter k values (0.04–0.24 y−1) decreased with depth and increased from early to late successional sites, with Empodisma roots having the slowest rates. Few strong relationships existed between litter quality and decomposition rates. In contrast, water table regime strongly influenced decomposition rates; k values for the “standard” Typha litter decreased exponentially as period of saturation increased, irrespective of site successional status, nutrients, or other factors. Lower water tables in the more aerated later successional sites have led to faster decomposition rates. Ongoing drainage combined with the potential impacts of climate change may increase organic matter decomposition and accelerate carbon release into the atmosphere.
Bog peat soils have been accumulating at Wellington Plain peatland, Victoria, Australia for the last 3300 years. Now, dried peat soils are common adjacent to bog peats. The 14C basal age of dried peat is not different from the 14C basal age of bog peat, which supports the theory that dried peat formed from bog peat. A novel application of 210Pb dating links the timing of this change with the introduction of livestock to Wellington Plain in the mid‐1800s. Physical loss of material appears to have been the dominant process removing material as bog peats drained to form dried peats, as indicated by the mass balances of carbon and lead. This research has implications for the post‐fire and post‐grazing restoration of bogs in Victoria's Alpine National Park, and the contribution of peat soils to Australia's carbon emissions.