Management of Agriculture to Preserve Environmental Values of the Great Barrier Reef, Australia

Abstract

Coral reef and seagrass ecosystems of the Great Barrier Reef (GBR) are in severe decline. Water quality associated with pollutant discharge from the rivers discharging into the GBR is a major issue for these GBR ecosystems and associated species such as dugongs, turtles and fi sh. The main source of river pollution is agriculture with sugarcane cultivation, beef grazing, grain cropping and horticulture the principal industries. Discharge to the GBR is of poor quality in many rivers, contaminants are present in the GBR lagoon at concentrations likely to cause environmental harm and the causal relationship between poor water quality and declining GBR ecosystem health is well understood. Action to improve management practices to reduce sediment, fertiliser and pesticide losses from farms is being taken and the pollutant loading of river discharge reduced. Improved practices are funded through the combined efforts of Australian Governments (Federal, State and local) and farmers. Whether these improved practices and the pollution reductions achieved are suffi cient to improve GBR ecosystem health is not certain in the face of other threats to the GBR such as climate change and large scale coastal development associated with urban and port expansion.

Full text

275© Springer Science+Business Media Dordrecht 2015
L. Chicharo et al. (eds.), Ecosystem Services and River Basin Ecohydrology,
DOI 10.1007/978-94-017-9846-4_14
Management of Agriculture to Preserve
Environmental Values of the Great Barrier
Reef, Australia
Jon Brodie , Stephen Lewis , Aaron Davis , Zoe Bainbridge ,
Dominique O’Brien , Jane Waterhouse , Michelle Devlin ,
and Colette R. Thomas
Abstract Coral reef and seagrass ecosystems of the Great Barrier Reef (GBR) are
in severe decline. Water quality associated with pollutant discharge from the rivers
discharging into the GBR is a major issue for these GBR ecosystems and associated
species such as dugongs, turtles and fi sh. The main source of river pollution is agri-
culture with sugarcane cultivation, beef grazing, grain cropping and horticulture the
principal industries. Discharge to the GBR is of poor quality in many rivers, con-
taminants are present in the GBR lagoon at concentrations likely to cause environ-
mental harm and the causal relationship between poor water quality and declining
GBR ecosystem health is well understood. Action to improve management prac-
tices to reduce sediment, fertiliser and pesticide losses from farms is being taken
and the pollutant loading of river discharge reduced. Improved practices are funded
through the combined efforts of Australian Governments (Federal, State and local)
and farmers. Whether these improved practices and the pollution reductions
achieved are suffi cient to improve GBR ecosystem health is not certain in the face
of other threats to the GBR such as climate change and large scale coastal develop-
ment associated with urban and port expansion.
Keywords Watershed management • Coral reefs • Agricultural pollution • Nutrients
• Pesticides
1 Introduction
Globally most coral reefs are threatened by human activities (Burke et al. 2011 ) and
show signs of some level of degradation (Pandolfi et al. 2003 ). Reefs are exposed to
a combination of stresses including destructive fi shing practices; overfi shing;
J. Brodie (*) • S. Lewis • A. Davis • Z. Bainbridge • D. O’Brien
J. Waterhouse • M. Devlin • C. R. Thomas
Catchment to Reef Research Group, Centre for Tropical Water & Aquatic Ecosystem
Research , James Cook University , Townsville 4811 , Australia
e-mail: jon.brodie@jcu.edu.au

276
land- sourced pollution of sediment, nutrients, pesticides, toxic metals and toxic
synthetic organic chemicals; coral predator outbreaks linked to trophic changes in
the system, particularly the crown of thorns starfi sh; bleaching resulting from global
climate change; ocean acidifi cation; and increased incidence of and severity of coral
diseases (Halpern et al. 2008 ). These anthropogenic stresses have led to severe
declines in coral cover on most global coral reef areas from values near 60 % more
than 50 years ago to 5–20 % recently, and led to persistent shifts from coral domi-
nance to non-coral and algal dominance (Bruno and Selig 2007 ; Hughes et al. 2010 ).
Seagrass meadows are in an equally threatened state globally (Unsworth et al. 2014 )
including the Western Pacifi c (Short et al. 2014 ). Many of the stresses affecting
tropical seagrasses are the same as for coral reefs – e.g. land-sourced pollution and
climate change.
A large range of approaches to manage the coastal zone have been developed
including Integrated Coastal Zone Management (ICZM), Ecosystem Based
Management (EBM), Marine Protected Areas (MPAs) and Integrated Marine (and
Spatial) Planning (IMP). In addition there are many approaches to managing catch-
ments (watersheds) which can be grouped into ‘Integrated Catchment Management’.
A few approaches also address the catchment – marine waters continuum and man-
aging the land-sea boundary (e.g. Alvarez-Romero et al. 2011 ). In many cases, there
are defi ciencies in Marine Protected Area (MPA) management around the world in
terms of size, spatial planning, representativeness, focus on limited impacts and
lack of enforcement (Mora et al. 2006 ; Christie and White 2007 ; Osmond et al.
2010 ) and for ignoring the need for complementary terrestrial pollutant manage-
ment. The Great Barrier Reef (GBR) on the other hand is generally seen as the best
example of Ecosystem Based Management (EBM) (e.g. Ruckelshaus et al. 2008 ),
MPA design and implementation (Fernandes et al. 2005 ; Agardy et al. 2011 ),
Integrated Marine Planning (Dickinson et al. 2010 ) and to some extent combined
ICZM and MPA design (Douvere 2008 ; Nobre 2011 ) with well-designed gover-
nance structures (Dale et al. 2013 ). However recently, with the severe declines in
coral cover, seagrass health and dugong populations, it is more evident that manage-
ment of the GBR has also failed (Brodie and Waterhouse 2012 ).
The GBR is an extensive coral reef system lying off the north east Australian
coast (Fig. 1 ) which also contains high value areas of seagrass and mangroves, and
a range of iconic megafauna including whales, dugongs, turtles, sharks, dolphins
and large fi sh. The area is 344,000 km
2 with around 25,000 km
2 of coral reefs (Day
and Dobbs 2013 ) and an adjacent catchment area of 400,000 km
2 (Brodie et al.
2012 ). The GBR has been managed as a national Marine Park since 1975 ( Great
Barrier Reef Marine Park Act 1975 ), and listed as a World Heritage Area (WHA) in
1981 (Lawrence et al. 2002 ). The GBR has been subject to an intensive management
regime involving both the Australian and Queensland State Governments for 40
years focussing on managed use and ecosystem protection. The actual Marine Park
falls under Australian Government jurisdiction but the adjacent catchments are
within the jurisdiction of the Queensland State Government. These jurisdictional
factors lead to political issues when adopting an ecosystem based approach to man-
agement and in addressing land based impacts.
J. Brodie et al.

277
Fig. 1 The Great Barrier Reef showing the reefs, catchments and major rivers, land uses on the
catchments and major cities and towns
Management of Agriculture to Preserve Environmental Values…

278
Live coral cover on the mid shelf of the GBR has sharply declined from levels
near 50 to 60 % in the 1960s to less than 14 % currently (Hughes et al. 2011 ; De’ath
et al. 2012 ). The causes of the decline include: land-sourced pollution of sediment,
nutrients (with the associated crown-of-thorns starfi sh outbreaks), and pesticides
(Brodie et al. 2005 , 2011 ; De’ath and Fabricius 2010 ; Fabricius et al. 2005 , 2010 ;
Lewis et al. 2009 ); coral bleaching/mortality and physical damage associated with
climate change including increasing incidence of severe storms (cyclones) (Osborne
et al. 2011 ; De’ath et al. 2012 ); ocean acidifi cation (Cooper et al. 2008 ; De’ath et al.
2009 ); and coral diseases (Haapkylä et al. 2011 ). Similar declines have been
observed on inshore reefs of the GBR, although the monitoring record is much
shorter (Thompson et al. 2011 ). A recent series of large river discharge events have
caused acute mortality to coastal reefs associated with the low salinity (Jones and
Berkelmans 2014 ) and polluted water (Devlin et al. 2012a ).
Seagrass health and abundance is also under anthropogenic threat (Grech et al.
2011 ), with recent declines associated with large river discharge events of polluted
water (Petus et al. 2014 ) and severe cyclones (Rasheed et al. 2014 ). The 2010/11
major river discharge events from GBR rivers associated with the strong La Nina
and Tropical Cyclone Tasha intense rainfall and the physical effects of Category 5
Tropical Cyclone Yasi have had devastating effects on large areas of GBR seagrass
(Devlin et al. 2012a ) and subsequent increased mortality of dugongs and turtles
which depend on the seagrass for food. Populations of dugongs in the southern two
thirds of the GBR have declined over recent decades with numbers reducing at a
rate of 8.7 % a year between 1962 and 1999 from about 72,000 in the early 1960s
to 4,000 in the mid-1990s (Marsh et al. 2005 ). Increased dugong mortality coin-
cided with severe weather events of 2011 and 2013 and, in turn is linked to reduc-
tion in seagrass health and biomass from poor water quality.
Agriculture is the major land use on GBR catchments, with more than 90 % of
the total area used for beef grazing and sugarcane, grains, horticultural and cotton
cropping. Much of the cropping activity occurs on the coastal fl oodplains (Brodie
et al. 2012 ). The proximity of the high conservation value GBR to this agriculture
dominated catchment has raised concern as to the risk posed to the GBR from
agricultural- sourced pollution.
The GBR, however, receives not only pressures from adjoining catchments, but
is also ecologically dependent upon many of the upstream environments and pro-
cesses they support (Stoeckl et al. 2011 ). For example, coastal freshwater riverine
systems, wetlands, and mangrove ecosystems along the Queensland coast provide
habitat, nutrient and sediment cycling and trophic linkages that are vital to the
GBR. Degradation of these linkages erodes the ongoing functional integrity of the
GBR, with spillover effects upon ecosystem benefi ts such as tourism and fi sheries,
which propagate through to the social, ecological and economic systems that are
interdependent with them (Thomas et al. 2012 ).
Even from a purely economic perspective, the GBR is enormously valuable.
For example, the monetary value of ecosystem benefi ts provided by coral reefs
and coastal systems globally has been estimated to be worth over 2 billion (inter-
national) dollars per hectare per year (de Groot et al.
2012 ). Estimates of economic
J. Brodie et al.

279
value for the GBR reveal the signifi cance of this asset at the national level. For
example, an early study assessed the present value of the GBR at approximately
4.7 % of Australia’s annual gross domestic product (Oxford Economics 2009 ).
The direct economic contribution of the GBR to commercial expenditure was
recently estimated at just over AU$7 billion, of which tourism contributed
AU$6.4b, recreation AU$330 m, and commercial fi shing AU$190 m (Deloitte
Access Economics 2013 ).
Tourism is a substantial industry in GBR catchments, most notably in the Cairns/
Wet Tropics region. Snapshot studies of the tourism industry reveal the breadth and
diversity of the ecological structures and processes that support it. For example,
Stoeckl et al. ( 2010 ) report that each year, live-aboard dive boats are directly respon-
sible for generating at least AU$16 million worth of income in the Cairns/Port
Douglas region. Similarly, the annual value of tourism expenditure exclusively
attributable to whale-watching in Hervey Bay is over AU$7 m, and seasonally this
industry contributes approximately AU$30 m to the region each year (Knowles and
Campbell 2011 ; Wilson and Tisdell 2003 ).
The total recreational value of Australian coral reefs, including fi shing, is
approximately US$120/visitor (Brander et al. 2007 ). The fi shing component of rec-
reational reef trips can be signifi cant. For example, Prayaga et al. ( 2010 ) calculated
the consumer surplus per trip on the Capricorn Coast at AU$385.34 per (group) trip,
or approximately AU$5.53 m for this region of the GBR alone. Similarly, earlier
work by Fenton and Marshall ( 2001a ) reveals the total annual gross value of pro-
duction (GVP) for GBR charter fi shing businesses at approximately AU$23 m. By
contrast, the same study showed that annual GVP for commercial fi shing businesses
at that time was AU$224 m (Fenton and Marshall 2001b ).
Like tourism, commercial fi shing in the GBR is diverse, and many species are
dependent on seagrass meadows for substantial parts of their life cycle. Although
few studies have examined the economic contribution of GBR seagrasses to fi shery
values, the loss in 1995/96 of 12 700 ha of seagrasses in Australia has been associ-
ated with lost fi shery production of AU$235 000 (McArthur and Boland 2006 ). In
contrast, international estimates have valued the provision of mangrove wood and
fi sh nursery areas by mangroves and seagrasses at US$215,000 per hectare
(Thorhaug 1990 ).
These fi gures underrepresent the value of the GBR because they do not consider
indirect economic value or many non-use values. It has been suggested that the
indirect benefi ts to coastal protection afforded by GBR ecosystems are worth at
least $10 billion, and Australian non-use values may be in the order of $15.2 billion
(Oxford Economics 2009 ). Many non-use values remain unquantifi ed (Brander
et al. 2007 ). For example, ecotourists visiting Hervey Bay sea turtles and whales are
willing to pay AU$2 – 8 m per year to safeguard the survival of the species (Wilson
and Tisdell 2003 ). It is unclear whether these and similar benefi ts are being realised.
The functional integrity of GBR ecosystems strongly depends on the decisions
that are made by the agricultural sector. The social, economic, and ecological risks
and benefi ts of agricultural activities can be diffi cult to formulate and implement
because they arise externally to the GBR (i.e., “upstream”), and as such are often
Management of Agriculture to Preserve Environmental Values…

280
resolved externally. A systematic ecosystem-based approach will help clarify and
quantify important interdependencies that affect system functionality, and can
underpin effective policy formulation.
2 Agricultural Pollution and the GBR
Important land uses in the GBR catchment (Fig. 1 ) that cover a total area of
424,000 km
2 include rangeland beef grazing (314,000 km
2 ), sugarcane cultivation
(5,700 km
2 ), horticulture (630 km
2 ), other cropping including grain and cotton cul-
tivation (11,600 km
2 ), urban areas (2,600 km
2 ) and native forest (55,900 km
2 )
(Waterhouse et al. 2009 ). Discharges of suspended solids, nutrients and pesticides
to the GBR have increased greatly over the last 150 years (Kroon et al. 2012 ) due to
this extensive development (Waterhouse et al. 2012 ).
Mean annual suspended sediment (SS) loads to the GBR has increased by 5.5
times to 17,000 ktonnes/year (Kroon et al. 2012 ) since European settlement in the
GBR catchment area (GBRCA) (c. 1850). The large beef grazing dominated catch-
ments of the Fitzroy and Burdekin contribute over 50 % (7,400 ktonnes/year) to the
mean annual anthropogenic (human caused) SS load of 14,000 ktonnes/year to the
GBR lagoon (Kroon et al. 2012 ). Hillslope, streambank and gully erosion all con-
tribute to the SS discharge with major variations between individual catchments
(Bartley et al. 2010a , b ; Wilkinson et al. 2013 ). Erosion may be severe in areas of
cropping and urban development on high slope lands but such areas are of smaller
extent than agriculture but may be a local threat to coastal reefs and seagrass areas.
Port dredging and spoil dumping is an existing large source of remobilized sediment
in the GBR and likely to increase greatly in the next decade (Brodie 2014 ) with cur-
rently poor management and governance arrangements (Grech et al. 2013 ).
Mean annual total nitrogen (TN) load to the GBR lagoon has increased by 5.7
times to 80,000 tonnes/year (Kroon et al. 2012 ). The anthropogenic nitrogen load
comprises 11,000 tonnes/year dissolved inorganic nitrogen (DIN), 6,900 tonnes/
year of dissolved organic nitrogen (DON), and 52,000 tonnes/year of particulate
nitrogen (PN). Similarly, the mean annual total phosphorus (TP) load has increased
by 8.9 times to 16,000 tonnes/year, with the anthropogenic phosphorus loads com-
prising 800 tonnes/year of dissolved inorganic phosphorus (DIP), 470 tonnes/year
of dissolved organic phosphorus (DOP), and 13,000 tonnes/year of particulate
phosphorus (PP). These nutrient increases are driven by the application of fertiliser
on sugar cane, horticulture and other cropping areas in the GBRCA (Waterhouse
et al. 2012 ), and losses of particulate bound nutrients from agricultural and urban
lands due to soil erosion (Waterhouse et al. 2012 ). Pesticides would have been
absent in runoff to the GBR prior to European settlement but now at least 30,000 kg/
year of herbicides is discharged to the GBR (Kroon et al. 2012 ). This estimate com-
prises photosystem-II (PSII) inhibiting herbicides only (atrazine, ametryn, hexazi-
none, diuron, simazine and tebuthiuron), for which monitoring information exists.
J. Brodie et al.

281
This is an underestimate of the total pesticide load to the GBR as many pesticides
known to be used in the GBRCA and hence have the potential to be discharged to
the GBR are not monitored. Atrazine, ametryn, hexazinone, and diuron originate
predominantly from the sugarcane industry (Bainbridge et al. 2009 ; Davis et al.
2012 , 2013 ), with atrazine also being used in grains cropping, and tebuthiuron and
simazine originating from the beef grazing industry and forestry plantations, respec-
tively (Lewis et al. 2009 ; Shaw et al. 2010 ; Waterhouse et al. 2012 ).
In 2013 the current state of knowledge regarding the degradation of Great Barrier
Reef ecosystems due to terrestrial pollutant runoff was reviewed and a ‘Scientifi c
Consensus Statement’ was prepared for the Queensland Government (Brodie et al.
2013 ). The conclusions were:
1. The decline of marine water quality associated with terrestrial runoff from the
adjacent catchments is a major cause of the current poor state of many of the key
marine ecosystems of the Great Barrier Reef.
2. The greatest water quality risks to the Great Barrier Reef are from nitrogen dis-
charge, associated with crown-of-thorns starfi sh outbreaks and their destructive
effects on coral reefs, and fi ne sediment discharge which reduces the light avail-
able to seagrass ecosystems and inshore coral reefs. Pesticides pose a risk to
freshwater and some inshore and coastal habitats.
3. Recent extreme weather – heavy rainfall, fl oods and tropical cyclones – have
severely impacted marine water quality and Great Barrier Reef ecosystems.
Climate change is predicted to increase the intensity of extreme weather events.
4. The main source of excess nutrients, fi ne sediments and pesticides from Great
Barrier Reef catchments is diffuse source pollution from agriculture.
5. Improved land and agricultural management practices are proven to reduce the
runoff of suspended sediment, nutrients and pesticides at the paddock scale.
3 Management of Agricultural Pollution for the GBR
3.1 Background
During the 1980s and 1990s, research and monitoring in the GBRCA and GBR
identifi ed land runoff of pollutants as a threat to the health of the GBR and provided
an understanding of (i) pollutant generation in the GBRCA and the land uses/ agri-
cultural industries and landscape processes contributing to the pollution, (ii) trans-
port of pollutants from the GBRCA into the GBR, (iii) dispersion of pollutants in
the GBR waters, (iv) effects of pollutants on specifi c GBR organisms and ecosys-
tems, (v) management options to reduce pollution, and (vi) socio-economic and
political issues in implementing improved management (Brodie et al. 2001 ; Furnas
2003 ). A major assumption was that point source pollution from sewage and indus-
trial waste discharge were already well managed and in most cases, regulated.
Management of Agriculture to Preserve Environmental Values…

282
3.2 Reef Plan
In 2003, the Australian and Queensland Governments jointly released the Reef Plan
(Queensland Department of the Premier and Cabinet 2003 ). The plan aimed to halt
and reverse the decline in water quality entering the Reef within 10 years (i.e. by
2013) by reducing diffuse pollution from agriculture. The Plan has objectives: (i)
Reduce the load of pollutants from diffuse sources in the water entering the Reef,
and (ii) Rehabilitate and conserve areas of the Reef catchment that have a role in
removing water borne pollutants. In 2009, Reef Plan 2003 was revised and updated
(Queensland Department of the Premier and Cabinet 2009 ) with better defi ned tar-
gets and actions and then a revised version was released in 2013 (Queensland
Department of the Premier and Cabinet 2013 ). In addition to Reef Plan’s 2003 aims
and objectives, Reef Plan 2013 also has the somewhat visionary objective to ensure
that “by 2020 the quality of water entering the GBR from adjacent catchments has
no detrimental impact on the health and resilience of the GBR”. Reef Plan 2009 had
load reduction targets of (i) a minimum 50 % reduction in nitrogen and phosphorus
loads at the end of catchments by 2013, (ii) a minimum 50 % reduction in pesticides
at the end of catchments by 2013, (iii) a minimum of 50 % late dry season ground-
cover on dry tropical grazing land by 2013, and (iv) a minimum 20 % reduction in
sediment load at the end of catchments by 2020. Given by 2013 the Reef Plan tar-
gets were known not to have been met Reef Plan 2013 set new targets with length-
ened implementation timelines and generally reduced standards (see below). The
Reef Plan 2013 targets:
Water quality targets (by 2018)
• At least a 50 % reduction in anthropogenic end-of-catchment dissolved inorganic
nitrogen loads in priority areas.
• At least a 20 % reduction in anthropogenic end-of-catchment loads of sediment
and particulate nutrients in priority areas.
• At least a 60 % reduction in end-of-catchment pesticide loads in priority areas.
Land and catchment management targets (by 2018)
• 90 % of sugarcane, horticulture, cropping and grazing lands are managed using
best management practice systems (soil, nutrient and pesticides) in priority areas.
• Minimum 70 % late dry season groundcover on grazing lands.
• The extent of riparian vegetation is increased.
• There is no net loss of the extent, and an improvement in the ecological processes
and environmental values, of natural wetlands.
Large changes in many of the targets were made in Reef Plan 2013 including
lowering targets for nitrogen and phosphorus loads, an unchanged sediment load
target and a small tightening of the pesticide load target (from 50 % reduction in
J. Brodie et al.

283
loads to 60 % reduction). In 2009, a 50 % reduction in TN load was required by
2013 whereas in 2013 we estimate a 36 % reduction is all that is required by 2018.
Similarly for TP, in 2009 a 50 % reduction was required whereas in 2013 only a
16 % reduction is required.
3.3 Reef Rescue
In 2007, the Federal Government implemented Reef Rescue, an AU $200 million
investment for on-ground works, monitoring, research and partnerships over 5 years
(Brodie et al. 2012 ). This voluntary program’s objective is to improve the water
quality of the GBR lagoon by increasing the adoption of land management practices
that reduce the run-off of nutrients, pesticides and sediments from agricultural land.
Whilst forming an integral component of Reef Plan 2009, Reef Rescue has its own
5-year outcome targets (i.e. by 2013). Both initiatives specify management action,
catchment condition and end-of-catchment pollutant load targets for 2013 reported
by catchment, regional and GBR-wide scales (Brodie et al. 2012 ). In 2013, Reef
Rescue 2 was announced with a further A$200 million funding over the period
2014–2018. From 2008 Reef Rescue funded on-ground land management projects
across the GBRCA with fi nancial contributions from farmers, mainly in the sugar-
cane and grazing industries but also in dairy farming and horticulture. Projects
include the introduction of new farming practices; fencing along streams for cattle
management with off-stream watering points; pasture management through grazing
pressure management; reduced fertiliser use through more effi cient application
techniques; machinery modifi cations including harvesters, fertiliser and pesticide
application equipment; and cultivation and tillage equipment and practices.
3.4 Great Barrier Reef Protection Amendment Act 2009
The Queensland Government introduced the Great Barrier Reef Protection
Amendment Act 2009 (Reef Protection Package) in 2009. This Act introduces regu-
lations to improve the quality of water entering the GBR in sugarcane growing and
cattle grazing properties in the Burdekin Dry Tropics, Wet Tropics and Mackay
Whitsunday Regions in North Queensland. The Act requires (i) Farm Environmental
Risk Management Plans in sugarcane cultivation and beef grazing, (ii) Fertiliser
management in sugarcane, (iii) Erosion management in grazing through managing
pasture cover, and (iv) Pesticide management through application techniques and
buffer strips.
Management of Agriculture to Preserve Environmental Values…

284
3.5 Management Effectiveness
The effectiveness of currently recommended practices as well as newer Best
Management Practices has been assessed (Thorburn et al. 2013 ; Thorburn and
Wilkinson 2013 ) including using nitrogen fertiliser management systems such as
‘Six Easy Steps’ (Schroeder et al. 2010 ) and the ‘nitrogen replacement’ technique
(Thorburn et al. 2011a , b ; Webster et al. 2012 ) to reduce the current considerable
losses of nitrogen from sugarcane cultivation. For herbicide management Masters
et al. ( 2013 ) showed that Best Management Practices in sugarcane including con-
trolled traffi c resulted in load reductions of 60 %, 55 %, 47 %, and 48 % for ame-
tryn, atrazine, diuron and hexazinone respectively. Herbicide losses in runoff were
also reduced by 32–42 % when applications were banded rather than broadcast
(Masters et al. 2013 ), a similar result to that shown in other sugarcane studies
(Oliver et al. 2014 ) and cotton cropping systems in the Fitzroy catchment (Silburn
et al. 2013 ).
In rangeland beef grazing lands, research into the effectiveness of pasture cover
as an erosion prevention management technique have shown that grazing in semi-
arid pastures should be managed to maintain >50 % ground cover to avoid excessive
runoff and soil erosion, degradation of soil productivity and to maintain good off-
site water quality (Silburn 2011a , b ; Silburn et al. 2011 ). Reducing erosion in graz-
ing lands is principally implemented through maintaining ground cover and biomass
of pastures, especially during the dry season and droughts. Gully networks caused
by livestock grazing are also important sources of sediment and targeted vegetation
management will be important for reducing gully erosion (Thorburn et al. 2013 ).
Other research has investigated the role and effectiveness of riparian forests and
wetlands (constructed and natural) on trapping catchment pollutants (e.g. McJannet
et al. 2011a , b ; Connor et al. 2013 ). In general small wetlands (either natural or
constructed) trap little sediment, phosphorus or nitrogen in north Queensland tropi-
cal climatic conditions.
The possibility of reaching the overall goal of Reef Plan (see above) of ‘no det-
rimental impact’ is in question given that current ‘Best Management Practices’ may
not be enough to achieve this outcome (Kroon 2012 ; Thorburn and Wilkinson
2013 ). Modeling of land-use adoption scenarios across the entire GBR has shown
that complete adoption of current best management practices in grazing and sugar-
cane would be suffi cient to meet the Reef Plan targets for photosystem II herbicides,
but are uncertain for suspended sediment, nitrogen and phosphorus (Thorburn and
Wilkinson
2013 ; Waters et al. 2013 ) and unlikely to meet the desired ecological
outcomes (Kroon
2012 ). If Reef Plan targets and goals are not met in the identifi ed
time frame (2018 and 2020), the conditions of inshore GBR ecosystems are unlikely
to improve in the medium-term future given other major issues such as climate
change are not being managed. The defi nition of specifi c ecological conditions to
support a healthy and resilient ecosystem and hence ‘ecologically relevant’ load
targets (Brodie et al. 2009 ) would enable an informed debate on the management
actions and policy instruments required to achieve these ecological conditions. The
J. Brodie et al.

285
social and economic costs of meeting the targets are not well understood, nor are the
trade-offs required to meet long term Reef Plan goals (Dale et al. 2013 ).
3.6 Governance
Partnerships for effective governance for the GBR have been relatively well studied
(e.g. Robinson et al. 2011 ) and evaluated using a SMART (Specifi c, Measurable,
Achievable, Relevant and Timed) assessment (Robinson et al. 2009 ). By incorporat-
ing the range of local needs, values, aspirations and priorities into water quality
objectives and values, water quality improvement plans are more likely to be sup-
ported by local communities (Bohnet et al. 2011 ; Tsatsaros et al. 2013 ).
At the GBR scale governance and its infl uence on effective environmental man-
agement has been reviewed by Dale et al. ( 2013 ) using a risk based approach. They
note that in the analysis of governance systems designed to lead to better gover-
nance the following key points are relevant:
• Best effect in participatory rather than expert-assessment contexts. To establish
better foundations for lasting reform, risk analysis of governance systems is best
applied in participatory decision-making, enabling all participants to jointly
analyse the health of their governance and to negotiate and monitor appropriate
reforms in a structured way;
• Best applied within reform-oriented approaches. While risk analysis of gover-
nance systems can be a tool for dispassionate analysis by experts, its greatest
strength lies in providing the evidence required for more participatory approaches
to governance reform;
• A foundation for benchmarking and monitoring governance systems. Data out-
puts from risk analysis of governance systems create the ideal foundation, if
applied periodically and consistently, for establishing long-standing benchmarks
for governance systems, providing the foundation for monitoring progressive
improvements;
• Potential application in education and capacity building. Operated in a strongly
participatory way, or even within formal training, risk analysis of governance
systems provides a clear framework for the delivery of education about gover-
nance, currently in short supply;
• Determines risks and areas of strategic governance research. Within any con-
text, a useful outcome from the application of risk analysis of governance sys-
tems is the identifi cation of strategic research themes required to address
problems; and
• Need for leadership in, and responsibility for, facilitating continuous improve-
ment in governance. To be effective, all governance systems need leadership in
monitoring and driving continuous improvement. While government agencies
are often best placed to lead and resource such attention, leadership can and
should come from any key participants in the system. For best effect, the ongoing
Management of Agriculture to Preserve Environmental Values…

286
process of risk analysis needs dedicated resourcing, and all system participants
should be confi dent in those leading and managing analysis and reform.
3.7 Monitoring and Reporting
The success (or otherwise) of Reef Plan is assessed using an integrated monitoring,
assessment and reporting program – the Paddock to Reef Program (Carroll et al.
2012 ). The program commenced in 2009 and report cards are released regularly e.g.
the most recent in 2013 (The State of Queensland 2013 ). The program is built
around a number of components including (a) management practice adoption moni-
toring and auditing; (b) paddock monitoring and modelling involving collecting
runoff during actual rainfall events and rainfall simulation. Modelling is used to
extend results from one situation to another not part of the monitoring scheme; (c)
catchment monitoring and modelling to assess the water quality entering the GBR
lagoon and to determine trends in water quality over time; identify potential source
areas of contaminants; link plot to paddock to river scales; and validate and calibrate
the existing catchment models; (d) marine monitoring including inshore biological
monitoring of inshore coral reefs and intertidal seagrass meadows; and inshore
water quality and fl ood plume monitoring focussing on TSS, nutrients, Chl a , salin-
ity, pesticides, temperature, turbidity and light conditions; and (e) reporting on
progress through an annual ‘Report Card’ supported by detailed technical reports.
The latest report card released in 2013 shows that considerable progress has been
made with small but signifi cant reductions in suspended sediment, nutrient and pes-
ticide loads discharged to the GBR compared to earlier years (The State of
Queensland 2013 ).
4 Conclusions
Water quality associated with pollutant discharge from the GBRCA is still a major
issue for GBR ecosystems. Recent research confi rms that water discharge to the
GBR is of poor quality in many rivers and in the associated fl ood plumes (Devlin
et al. 2012a ; Kroon et al. 2012 ; Kennedy et al. 2012 ); contaminants are present in
the GBR lagoon at concentrations likely to cause environmental harm (Devlin et al.
2012b ; Lewis et al. 2009 , 2012 ; Schaffelke et al. 2012 ; Shaw et al. 2010 ); and evi-
dence of the causal relationship between water quality and GBR ecosystem health
is clear (Brodie et al. 2011 ; Fabricius et al. 2010 ; Lewis et al. 2012 ; Petus et al.
2014 ).
Currently, while management action is being taken and improvements in the pol-
lutant loading of river discharge improved, whether this is enough to achieve the
Reef Plan targets or the most appropriate form of management is not yet known
(Thorburn and Wilkinson
2013 ; Kroon 2012 ). However, it is expected that
J. Brodie et al.

287
measurable improvements in river and coastal marine water quality, or ecosystem
health, may not be detected for up to several decades (Darnell et al. 2012 ) .
References
Agardy T, di Sciara GN, Christie P (2011) Mind the gap: addressing the shortcomings of marine
protected areas through large scale marine planning. Mar Policy 35:226–232
Alvarez-Romero JG, Pressey RL, Ban NC, Vance-Borland K, Willer C, Klein CJ, Gaines SD
(2011) Integrated landesea conservation planning: the missing links. Annu Rev Ecol Evol Syst
42:381–409
Bainbridge ZT, Brodie JE, Faithful JW, Sydes DA, Lewis SE (2009) Identifying the land-based
sources of suspended sediments, nutrients and pesticides discharged to the Great Barrier Reef
from the Tully-Murray Basin, Queensland, Australia. Mar Freshw Res 60:1081–1090
Bartley R, Wilkinson SN, Hawdon AA, Abbott BN, Post DA (2010a) Impacts of improved grazing
land management on sediment yields, Part 1: hillslope processes. J Hydrol 389:237–248
Bartley R, Wilkinson SN, Hawdon AA, Abbott BN, Post DA (2010b) Impacts of improved grazing
land management on sediment yields, Part 2: catchment response. J Hydrol 389:249–259
Bohnet IC, Roebeling PC, Williams KJ, Holzworth D, van Grieken ME, Pert PL, Kroon FJ,
Westcott DA, Brodie JE (2011) Landscapes toolkit – an integrated modeling framework to
assist stakeholders in exploring options for sustainable landscape development. Landsc Ecol
26:1179–1198
Brander LM, van Beukering P, Cesar HSJ (2007) The recreational value of coral reefs: a meta-
analysis. Ecol Econ 63:209–218
Brodie J (2014) Dredging the Great Barrier Reef: use and misuse of science. Estuar Coast Shelf
Sci 142:1–3. doi:
10.1016/j.ecss.2014.01.010
Brodie J, Waterhouse J (2012) A critical assessment of environmental management of the ‘not so
Great’ Barrier Reef. Estuar Coast Shelf Sci 104–105:1–22. doi:
10.1016/j.ecss.2012.03.012
Brodie J, Christie C, Devlin M, Haynes D, Morris S, Ramsay M, Waterhouse J, Yorkston H (2001)
Catchment management and the Great Barrier Reef. Water Sci Technol 43:203–211
Brodie J, Fabricius K, De’ath G, Okaji K (2005) Are increased nutrient inputs responsible for more
outbreaks of crown-of-thorns starfi sh? An appraisal of the evidence. Mar Pollut Bull
51:266–278
Brodie J, Lewis S, Bainbridge Z, Mitchell A, Waterhouse J, Kroon F (2009) Pollutant discharge
management target setting for rivers in the Great Barrier Reef catchment area. Mar Freshw Res
60:1141–1149
Brodie JE, Devlin MJ, Haynes D, Waterhouse J (2011) Assessment of the eutrophication status of
the Great Barrier Reef lagoon (Australia). Biogeochemistry 106:281–302. doi:
10.1007/
s10533-010-9542-2
Brodie J, Kroon F, Schaffelke B, Wolanski E, Lewis S, Devlin M, Bohnet IC, Bainbridge Z,
Waterhouse J, Davis A (2012) Terrestrial pollutant runoff to the Great Barrier Reef: an update
on issues, priorities and management responses. Mar Pollut Bull 65:81–100
Brodie J, Waterhouse J, Schaffelke B, Johnson J, Kroon F, Thorburn P, Rolfe J, Lewis S, Warne M,
Fabricius K, McKenzie L, Devlin M (2013) Reef water quality scientifi c consensus statement
2013. Department of the Premier and Cabinet, Queensland Government, Brisbane
Bruno JF, Selig ER (2007) Regional decline of coral cover in the Indo-Pacifi c: timing, extent, and
subregional comparisons. PLoS One 28:e711. doi:
10.1371/journal.pone.0000711
Burke L, Reytar K, Spalding M, Perry A (2011) Reefs at risk revisited. World Resources Institute,
Washington, DC, p 114. Available at
www.wri.org
Carroll C, Waters D, Vardy S, Silburn DM, Attard S, Thorburn PJ, Davis AM, Schmidt M, Wilson
B, Clark A (2012) A paddock to reef monitoring and modelling framework for the Great
Barrier Reef: paddock and catchment component. Mar Pollut Bull 65:136–149
Management of Agriculture to Preserve Environmental Values…

288
Christie P, White AT (2007) Best practices for improved governance of coral reef marine protected
areas. Coral Reefs 26:1047–1056
Connor S, Nelson PN, Armour JD, Henault C (2013) Hydrology of a forested riparian zone in an
agricultural landscape of the humid tropics. Agric Ecosys.Environ.
http://dx.doi.org/10.1016/j.
agee.2011.12.006
Cooper TF, De’ath G, Fabricius KE, Lough JM (2008) Declining coral calcifi cation in massive
porites in two nearshore regions of the northern Great Barrier Reef. Glob Chang Biol
14:529–538
Dale A, Vella K, Pressey RL, Brodie J, Yorkston H, Potts R (2013) Risk analysis across governance
systems: a Great Barrier Reef case study. Environ Lett 8. doi:
10.1088/1748-9326/8/1/015037
Darnell R, Henderson B, Kroon FJ, Kuhnert P (2012) Statistical power of detecting trends in total
suspended sediment loads to the Great Barrier Reef. Mar Pollut Bull 65:203–209
Davis AM, Lewis SE, Bainbridge ZT, Brodie JE, Glendenning L, Turner R (2012) Dynamics of
herbicide transport and partitioning under event fl ow conditions in the lower Burdekin region,
Australia. Mar Pollut Bull 65:182–193
Davis AM, Thorburn PJ, Lewis SE, Bainbridge ZT, Attard SJ, Milla R, Brodie JE (2013)
Environmental impacts of irrigated sugarcane production: herbicide run-off dynamics from
farms and associated drainage systems. Agric Ecosyst Environ 180:123–135
Day JC, Dobbs K (2013) Effective governance of a large and complex cross-jurisdictional marine
protected area: Australia’s Great Barrier Reef. Mar Policy 41:14–24
de Groot R, Brander L, van der Ploeg S, Costanza R, Bernard F, Braat L, Christie M, Crossman N,
Ghermandi A, Hein L, Hussain S, Kumar P, McVittie A, Portela R, ten Rodriguez LC, Brink P,
van Beukering P (2012) Global estimates of the value of ecosystems and their services in mon-
etary units. Ecosystem Serv 1:50–61
De’ath G, Fabricius KE (2010) Water quality as a regional driver of coral biodiversity and macroal-
gae on the Great Barrier Reef. Ecol Appl 20:840–850
De’ath G, Lough JM, Fabricius KE (2009) Declining coral calcifi cation on the Great Barrier Reef.
Science 323:116–119
De’ath G, Fabricius K, Sweatman H, Puotinen M (2012) The 27-year decline of coral cover on the
Great Barrier Reef and its causes. Proc Natl Acad Sci. doi:
10.1073/pnas.1208909109
Deloitte Access Economics (2013) Economic contribution of the Great Barrier Reef. Great Barrier
Reef Marine Park Authority, Townsville
Devlin M, Brodie J, Wenger A, da Silva E, Alvarez- Romero JG, Waterhouse J, McKenzie L
(2012a) Extreme weather conditions in the Great Barrier Reef: drivers of change? Proceedings
of the 12th international coral reef symposium, Cairns, Australia, 9–13 July 2012
Devlin MJ, McKinna LW, Álvarez-Romero JG, Petus C, Abott B, Harkness P, Brodie J (2012b)
Mapping the pollutants in surface riverine fl ood plume waters in the Great Barrier Reef,
Australia. Mar Pollut Bull 65(4–9):224–235
Dickinson M, Rutherford M, Gunton T (2010) Principals for integrated marine planning: a review
of international experience. Environ J 37:21–46
Douvere F (2008) The importance of marine spatial planning in advancing ecosystem-based sea
use management. Mar Policy 32:762–771
Economics O (2009) Valuing the effects of Great Barrier Reef bleaching. Great Barrier Reef
Foundation, Brisbane
Fabricius K, De’ath G, McCook L, Turak E, Williams D (2005) Changes in algal, coral and fi sh
assemblages along water quality gradients on the inshore Great Barrier Reef. Mar Pollut Bull
51:384–398
Fabricius K, Okaji K, De’ath G (2010) Three lines of evidence to link outbreaks of the crown-of-
thorns seastar Acanthaster planci to the release of larval food limitation. Coral Reefs
29:593–605
Fenton DM, Marshall NA (2001a) A guide to the fi shers of Queensland. Part A. TRC-analysis and
social profi les of Queensland’s commercial fi shing industry. CRC Reef Research Centre,
Townsville, Australia
J. Brodie et al.

289
Fenton DM, Marshall NA (2001b) A guide to the fi shers of Queensland. Part C. TRC-analysis and
social profi les of Queensland’s charter fi shing industry. CRC Reef Research Centre, Townsville
Fernandes L, Day J, Lewis A, Slegers S, Kerrigan B, Breen D, Cameron D, Jago B, Hall J, Lowe
D, Innes J, Tanzer J, Chadwich V, Thompson L, Gorman K, Simmons M, Barnett B, Sampson
K, De’ath G, Mapstone B, Marsh H, Possingham H, Ball I, Ward T, Dobbs K, Aumend J, Slater
D, Stapleton K (2005) Establishing representative no-take areas in the Great Barrier Reef:
largescale implementation of theory on marine protected areas. Conserv Biol 19:1733–1744
Furnas M (2003) Catchments and corals: terrestrial runoff to the Great Barrier Reef. Australian
Institute of Marine Science, Townsville, 334 pp
Grech A, Coles R, Marsh H (2011) A broad-scale assessment of the risk to coastal seagrasses from
cumulative threats. Mar Policy 35(5):560–567
Grech A, Bos M, Brodie J, Coles R, Dale A, Gilbert R, Hamann M, Marsh H, Neil K, Pressey B,
Rasheed M, Sheaves M, Smith A (2013) Guiding principles for the improved governance of
port and shipping impacts in the Great Barrier Reef. Mar Pollut Bull 75:8–20. doi:
10.1016/j.
marpolbul.2013.07.013
Haapkyla J, Unsworth RKF, Flavell M, Bourne DG, Schaffelke B, Willis BL (2011) Seasonal
rainfall and runoff promote coral disease on an inshore reef. PLoS One 6:e16893. doi:
10.1371/
journal.,pone.0016893
Halpern BB, Walbridge S, Selkoe KA, Kappel CV, Micheli F, D’Agrosa C, Bruno JF, Casey KS,
Ebert C, Fox HE, Fujita R, Heinemann D, Lenihan HS, Madin EMP, Perry MT, Selig ER,
Spalding M, Steneck R, Watson R (2008) A global map of human impact on marine ecosys-
tems. Science 319:948e952
Hughes TP, Graham NAJ, Jackson JBC, Mumby PJ, Steneck RS (2010) Rising to the challenge of
sustaining coral reef resilience. Trends Ecol Evol 25:633–642
Hughes TP, Bellwood DR, Baird AH, Brodie J, Bruno JF, Pandolfi JM (2011) Shifting base-lines,
declining coral cover, and the erosion of reef resilience. Comment on Sweatman et al. (2011).
Coral Reefs 30:653–660
Jones AM, Berkelmans R (2014) Flood Impacts in Keppel Bay, Southern Great Barrier Reef in the
aftermath of cyclonic rainfall. PLoS One 9(1):e84739. doi:
10.1371/journal.pone.0084739
Kennedy K, Schroeder T, Shaw M, Haynes D, Lewis S, Bentley C, Paxman C, Carter S, Brando V,
Bartkow M, Mueller J (2012) Long term monitoring of photosystem-II herbicides – correlation
with remotely sensed freshwater extent to monitor changes in the quality of water entering the
Great Barrier Reef, Australia. Mar Pollut Bull 65:292–305
Knowles T, Campbell R (2011) What’s a whale worth? Valuing whales for National Whale Day, a
report for the International Fund for Animal Welfare (IFAW), prepared by Economists at Large,
Melbourne, Australia
Kroon FJ (2012) Towards ecologically relevant targets for river pollutant loads to the Great Barrier
Reef. Mar Pollut Bull 65:261–266
Kroon FJ, Kuhnert KM, Henderson BL, Wilkinson SN, Kinsey-Henderson A, Brodie JE, Turner
RDR (2012) River loads of suspended solids, nitrogen, phosphorus and herbicides delivered to
the Great Barrier Reef lagoon. Mar Pollut Bull 65:167–181
Lawrence D, Kenchington R, Woodley S (2002) The Great Barrier Reef. Finding the right balance.
Melbourne University Press, Melbourne, p 296
Lewis SE, Brodie JE, Bainbridge ZT, Rohde KW, Davis AM, Masters BL, Maughan M, Devlin
MJ, Mueller JF, Schaffelke B (2009) Herbicides: a new threat to the Great Barrier Reef. Environ
Pollut 157:2470–2484
Lewis SE, Schaffelke B, Shaw M, Bainbridge ZT, Rohde KW, Kennedy KE, Davis AM, Masters
BL, Devlin MJ, Mueller JF, Brodie JE (2012) Assessing the risks of PS-II herbicide exposure
to the Great Barrier Reef. Mar Pollut Bull 65:280–291
Marsh H, De’ath G, Gribble N, Lane B (2005) Historical marine population estimates: triggers or
targets for conservation? The dugong case study. Ecol Appl 15:481–492. doi:
10.1890/04-0673
Masters B, Rohde K, Gurner N, Reid D (2013) Reducing the risk of herbicide runoff in sugarcane
farming through controlled traffi c and early-banded application. Agric Ecosyst Environ 180:29–39
Management of Agriculture to Preserve Environmental Values…

290
McArthur LC, Boland JW (2006) The economic contribution of seagrass to secondary production
in South Australia. Ecol Model 196:163–172
McJannet D, Wallace J, Keen R, Hawdon A, Kemei J (2011a) The fi ltering capacity of a tropical
riverine wetland: I. Water balance. Hydrol Process. doi:
10.1002/hyp.8108
McJannet D, Wallace J, Keen R, Hawdon A, Kemei J (2011b) The fi ltering capacity of a tropical
riverine wetland: II. Sediment and nutrient balances. Hydrol Process. doi:
10.1002/hyp.811
Mora C, Andrèfouët S, Costello MJ, Kranenburg C, Rollo A, Veron J, Gaston KJ, Myers RA
(2006) Coral reefs and the global network of marine protected areas. Science
312(5781):1750–1751
Nobre AM (2011) Scientifi c approaches to address challenges in coastal management. Mar Ecol
Prog Ser 434:279–289
Oliver DP, Anderson JS, Davis A, Lewis S, Brodie J, Kookana R (2014) Banded applications are
highly effective in minimizing herbicide migration from furrow-irrigated sugar cane. Sci Total
Environ 466–467:841–848
Osborne K, Dolman AM, Burgess SC, Johns KA (2011) Disturbance and the dynamics of coral
cover on the Great Barrier Reef (1995–2009). PLoS One 6(3):e17516. doi:
10.1371/journal.
pone.0017516
Osmond M, Airame S, Day JC, Caldwell M (2010) Lessons for marine spatial planning: a com-
parison of three marine protected area processes. Ocean Coast Manag 53:41–51
Pandolfi JM, Bradbury RH, Sala E, Hughes TP, Bjorndal KA, Cooke RG, McArdle D, McClenachan
L, Newman MJH, Paredes G, Warner RR, Jackson JBC (2003) Global trajectories of the long-
term decline of coral reef ecosystems. Science 301:955–958
Petus C, Collier C, Devlin M, Rasheed M, McKenna S (2014) Using MODIS data for understand-
ing changes in seagrass meadow health: a case study in the Great Barrier Reef (Australia). Mar
Environ Res 98:68–85
Prayaga P, Rolfe J, Stoeckl N (2010) The value of recreational fi shing in the Great Barrier Reef,
Australia: a pooled revealed preference and contingent behaviour model. Mar Policy
34:244–251
Queensland Department of the Premier and Cabinet (2003) Reef water quality protection plan; for
catchments adjacent to the Great Barrier Reef world heritage area. Queensland Department of
Premier and Cabinet, Brisbane.
http://www.reefplan.qld.gov.au/about/assets/reefplan-2003.pdf
Queensland Department of the Premier and Cabinet (2009) Reef water quality protection plan
2009: for the Great Barrier Reef world heritage area and adjacent catchments. Queensland
Department of Premier and Cabinet, Brisbane.
http://www.reefplan.qld.gov.au/resources/
assets/reef-plan-2009.pdf
Queensland Department of the Premier and Cabinet (2013) Reef water quality protection plan
2013: for the Great Barrier Reef world heritage area and adjacent catchments. Queensland
Department of Premier and Cabinet, Brisbane
Rasheed MA, McKenna SA, Carter AB, Coles RG (2014) Contrasting recovery of shallow and
deep water seagrass communities following climate associated losses in tropical north
Queensland, Australia. Mar Pollut Bull 83:491–499
Robinson CJ, Taylor BM, Pearson L, O’Donohue M, Harman B (2009) A SMART assessment of
water quality partnerships in Great Barrier Reef catchments. Aust J Environ Manag 16:84–93
Robinson CJ, Margerum RD, Koontz TM, Moseley C, Lurie S (2011) Policylevel collaboratives
for environmental management at the regional scale: lessons and challenges from Australia and
the United States. Soc Nat Resour 24:849–859
Ruckelshaus M, Klinger T, Knowlton N, DeMaster DP (2008) Marine ecosystem based manage-
ment in practice: scientifi c and governance challenges. Bioscience 58:53–63
Schaffelke B, Carleton J, Skuza M, Zagorskis I, Furnas MJ (2012) Water quality in the inshore
Great Barrier Reef lagoon: implications for long-term monitoring and management. Mar Pollut
Bull 65:249–260
Schroeder BL, Hurney AP, Wood AW, Moody PW (2010) Concepts and value of the nitrogen
guidelines contained in the Australian sugar industry’s ‘six easy steps’ nutrient management
program. In: Proceedings of the international society of sugar cane technologists, vol 27, 11 pp
J. Brodie et al.

291
Shaw M, Furnas MJ, Fabricius K, Haynes D, Carter S, Eaglesham G, Mueller JF (2010) Monitoring
pesticides in the Great Barrier Reef. Mar Pollut Bull 60:113–122
Short F, Coles RG, Fortes MD, Victor S, Isnain I, Andrew J, Seno A, Salik M (2014) Monitoring
in the Western Pacifi c region shows evidence of seagrass decline in line with global trends. Mar
Pollut Bull.
http://dx.doi.org/10.1016/j.marpolbul.2014.03.036
Silburn DM (2011a) Hillslope runoff and erosion on duplex soils in grazing lands in semi-arid
central Queensland. II. Simple models for suspended and bedload sediment. Soil Res
49:118–126
Silburn DM (2011b) Hillslope runoff and erosion on duplex soils in grazing lands in semi-arid
central Queensland III. USLE erodibility (K factors) and cover-soil loss relationships. Soil Res
49:127–134
Silburn DM, Carroll C, Ciesiolka CAA, deVoil RC, Burger P (2011) Hillslope runoff and erosion
on duplex soils in grazing lands in semi-arid central Queensland. Soil Res 49:105–117
Silburn DM, Foley JL, deVoil RC (2013) Managing runoff of herbicides under rainfall and furrow
irrigation with wheel traffi c and banded spraying. Agric Ecosyst Environ 180:40–53
Stoeckl N, Birtles A, Farr M, Mangott A, Curnock M, Valentine P (2010) Live-aboard dive boats
in the Great Barrier Reef: regional economic impact and the relative values of their target
marine species. Tour Econ 16(4):995–1018. doi:
10.5367/te.2010.0005
Stoeckl N, Hicks CC, Mills M, Fabricius K, Esparon M, Kroon F, Kaur K, Costanza R (2011) The
economic value of ecosystem services in the Great Barrier Reef: our state of knowledge. Ecol
Econ Rev 1219:113–133
The State of Queensland (2013) Great Barrier Reef 2011 report card. Reef water quality protection
plan. Published by the Reef Water Quality Protection Plan Secretariat. Queensland Government,
Brisbane, Australia
Thomas CR, Gordon IJ, Wooldridge S, Marshall P (2012) Balancing the tradeoffs between eco-
logical and economic risks for the Great Barrier Reef: a pragmatic conceptual framework. Hum
Ecol Risk Assess 18:69–91
Thompson A, Costello P, Davidson J, Logan M, Schaffelke B, Uthicke S, Takahashi M (2011) Reef
rescue marine monitoring program. Report of AIMS Activities – Inshore coral reef monitoring
2011. Report for Great Barrier Reef Marine Park Authority. Australian Institute of Marine
Science, Townsville, 128 pp
Thorburn PJ, Wilkinson SN (2013) Conceptual frameworks for estimating the water quality ben-
efi ts of improved agricultural management practices in large catchments. Agr Ecosyst Environ
180:192–209
Thorburn PJ, Biggs JS, Webster AJ, Biggs IM (2011a) An improved way to determine nitrogen
fertiliser requirements of sugarcane crops to meet global environmental challenges. Plant Soil
339:51–67. doi:
10.1007/s11104-010-0406-2
Thorburn PJ, Biggs JS, Attard SJ, Kemei J (2011b) Environmental impacts of irrigated sugarcane
production: nitrogen lost through runoff and leaching. Agric Ecosyst Environ 144:1–12.
doi:
10.1016/j.agee.2011.08.003
Thorburn P, Wilkinson S, Silburn M (2013) Water quality in agricultural lands draining to the Great
Barrier Reef: a review of causes, management and priorities. Agric Ecosyst Environ 180:4–20
Thorhaug A (1990) Restoration of mangroves and seagrasses – economic benefi ts for fi sheries and
mariculture. In: Berger JJ (ed) Environmental restoration. Science and strategies for restoring
the earth. Island Press, Washington, pp 265–281
Tsatsaros JH, Brodie JE, Bohnet IC, Valentine P (2013) Water quality degradation of coastal water-
ways in the wet tropics, Australia. Water Air Soil Pollut 224:1443
Unsworth RKF, van Keulen M, Coles RG (2014) Seagrass meadows in a globally changing envi-
ronment. Mar Pollut Bull 83:383–386
Waterhouse J, Grundy M, Brodie J, Gordon I, Yorkston H, Eberhard R (2009) Managing the catch-
ment of the Great Barrier Reef, Chapter 15. In: Ferrier R, Jenkins J (eds) Handbook of catch-
ment management. Blackwell Publishing, United Kingdom, pp 351–375
Waterhouse J, Brodie J, Lewis S, Mitchell A (2012) Quantifying the sources of pollutants to the
Great Barrier Reef. Mar Pollut Bull 65:394–406
Management of Agriculture to Preserve Environmental Values…

292
Waters D, Carroll C, Ellis R, McCloskey G, Hateley L, Packett R, Dougall C, Fentie B (2013)
Catchment modelling scenarios to inform GBR water quality targets.In: MODSIM2013, 20th
International Congress on Modelling and Simulation Society of Australia and New Zealand.
(Adelaide, Australia, 2013), pp 3204–3210
Webster AJ, Bartley R, Armour JD, Brodie JE, Thorburn PJ (2012) Reducing dissolved inorganic
nitrogen in surface runoff water from sugarcane production systems. Mar Pollut Bull
65:128–135
Wilkinson SN, Hancock GJ, Bartley R, Hawdon AA, Keen R (2013) Using sediment tracing to
identify sources of fi ne sediment in grazed rangelands draining to the Great Barrier Reef. Agric
Ecosyst Environ 180:90–102
Wilson C, Tisdell C (2003) Conservation and economic benefits of wildlife-based marine
tourism: sea turtles and whales as case studies. Hum Dimens Wildl Int J 8(1):49–58.
doi:
10.1080/10871200390180145
J. Brodie et al.