Scholarly article on topic 'The case for an ecosystem service approach to decision-making: an overview'

The case for an ecosystem service approach to decision-making: an overview Academic research paper on "Law"

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Academic research paper on topic "The case for an ecosystem service approach to decision-making: an overview"

10.1093/biohorizons/hzq013 Advance Access publication 12 April 2010

Review

The case for an ecosystem service approach w

to decision-making: an overview |

Joseph Hancock* t

School of Biology, University of St Andrews, St Andrews, Fife KY16 9TS, UK. b

* Corresponding author: 7 Cluny Avenue, Edinburgh EH10 4RN, UK. Tel: +44 1314472555. Email: Joseph.hancock@googlemail.com h

Supervisor: Professor Thomas R. Meagher, School of Biology, University of St Andrews, Fife KY16 9TS, UK. 0

........................................................................................................................................................................................................................................ |

The Earth's ecosystems supply human society with a stream of services, the sustained delivery of which remains crucial to our health, 0'

economic prosperity and personal and national security. Ecosystem services provide these benefits across a range of geographical scales 3

(local, regional and global) and to many different groups (individuals, businesses and governments). In spite of this, ecosystem services 0

are continually underrepresented and undervalued within decision-making situations. As a result, the capacity of ecosystems to supply a /

number of services—including the supply of food and freshwater, the regulation of disease and protection from natural hazards—has ^

been degraded worldwide, with serious consequences for human wellbeing. The actions of man are unwittingly depleting the planet's v

natural capital and putting such strain on the environment that the capacity of Earth's ecosystems to support future generations can no t

longer be taken for granted. To address this we need a new approach to the way that decisions are made at the interface of the environ- b

ment and society—one where the benefits and services provided by ecosystems are understood, evaluated and appropriately rep- 2

resented within the decision-making arena. By drawing attention to the failures and consequences of past and present attitudes in h

decision-making and resource management, this article frames a way forward to help avoid such problems in the future. Specifically, |

it outlines the rationale behind the need for an ecosystem service approach to decision-making and highlights some of the research T

needs that will help in selecting policies that sustain ecosystem services. h

Key words: ecosystem services, decision-making, millennium ecosystem assessment, ecosystem service approach. h

Submitted on 16 October 2009; accepted on 10 March 2010 3

Introduction marketable goods such as timber, food, fibre and fuels. As e

the human population doubled from 3 to 6 billion and the Z

Al1 people depend upon the environment and the services global economy increased more than 6-fold between 1960 |

provided by its ecosystems. Ecosystems provide such essential and the year 2000 there was a massive increase in demand 1

requirements as the food we ea^ the water we drink and the for these services.2' 3 Man responded by altering ecosystems t

air we breathe. They also supply a number of less obvious to enhance their productive capacity.4 Farms replaced forests 0

but equally critical services that underpin the health and and savannas, rivers were diverted to irrigate fields, fresh- U

prosperity of human society. For example: wetlands mitigate water aquifers were utilized and new technological advances 1

the effects of floods by storing water during heavy rains and made it possible for fishing fleets to harvest ever-greater pro- 2

act as natural filters by capturing and breaking down pollu- portions of global fish stocks.1 Changes like these have sup- 55

tants; and biogeochemical processes such as soil formation ported the unparalleled growth and progress of the human

and the cycling of nutrients underpin the functioning of a11 population over the last two centuries.5 On average,

ecosystems and make the planet fit for human habitation.1 incomes have grown, individuals live longer, and more

In recent years humans have made unparalleled changes to people are better nourished than has ever been the case.1 the world's ^o^te^ driven mainly to meet increased However, these changes have come at a cost. Modifying eco-

demands for particular ecosystem services that provide systems to enhance the supply of one particular service,

© The Author 2010. Published by Oxford University Press. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.5), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 188

typically a provisioning service such as food production, often degrades the capacity of the environment to provide a range of other services.

The crucial tradeoffs between ecosystem services are often ignored when decisions are made about how to manage environmental assets. Mangroves, for example, have been cleared to harvest timber and free up habitat for aquaculture, with the loss of critical services such as coastal storm protection, carbon storage, spawning and nursery habitat for a variety of species, as well as a reduction in water quality as a result of aquacultural pollution.7 Similarly, the clearing of rainforests for cropland and the harvest of timber results in the loss of services including the regulation of water balance and river flow, protection from soil erosion and landslides, carbon sequestration, local climate regulation, control of fire regimes and protection against the spread of pests and disease.8' 9 By overlooking the connections between ecosystem services and society's overall reliance upon their supply, many decision-makers threaten the sus-tainability and overall success of their development decisions.

The ecosystem service approach to decision-making puts ecosystem services at the centre of discussions on development and natural resource management. Although still in its infancy, this approach offers hope by providing decision-makers with a way to capture the two-way relationship between human wellbeing and the services supplied by ecosystems. In doing so it encourages decision-makers to consider society's dependence upon ecosystem services and to examine the impact of different decisions on the future supply of the whole range of ecosystem services.

Various efforts are generating momentum towards an ecosystem service approach to decision-making, such as the Natural Capital Project on the economic valuation of ecosystem services, the United Nations Environment Programme (UNEP) on the creation of ecosystem service markets,12 the World Wildlife Federation on payments,13 the UNEP World Conservation Monitoring Centre on indicators of service provision and the World Resources Institute on mainstreaming understanding of ecosystem services. 5 However, we are still someway off the paradigm shift needed to safeguard the future of ecosystems and the supply of their services. This article outlines the underlying principles behind the need for an ecosystem service approach to decision-making, and adds its voice to a growing number of those calling for change from the status quo. It builds upon the foundations laid by the United Nations Millennium Ecosystem Assessment (MA), synthesizing its key findings and presents a new approach to decision-making by highlighting the central role and importance of ecosystem services as the link between human systems and the environment. The following sections summarize the findings of the MA with regard to ecosystem services, outline case studies that highlight successful as well as unsuccessful integration

of the ecosystem service approach, and provide a roadmap for future development of the ecosystem service approach as a policy and decision-making tool.

Ecosystem change and the state of ecosystem service supply

The most comprehensive evaluation ever undertaken of the state and trends of the world's ecosystems and their capacity to support human wellbeing, the MA,1 found that 15 of the 24 ecosystem services that it assessed globally were being degraded and used in ways that could not be sustained. This scientific effort led by the United Nations involved the work of over 1300 experts from 96 countries and lasted for 4 years. This assessment classified ecosystem services in the following four broad categories:

• Provisioning services: these provide the raw materials that are consumed or used directly by humans such as food, fibre and timber.

• Regulating services: the benefits obtained from the regulation of ecosystem processes, including water filtration and purification, the regulation of disease, erosion control and pollination.

• Cultural services: the non-material benefits that people obtain from ecosystems such as recreation, spiritual enrichment and aesthetic experiences.

• Supporting services: the services that are necessary for the production of all other ecosystems services, including soil formation, nutrient cycling, oxygen production and photosynthesis.

The MA evaluated 24 ecosystem services (Table 1). It found that 15 were degraded or used in an unsustainable manner, and that only four were in an enhanced state.16 Of these enhanced services three were provisioning services (livestock, crops and aquacultural production). The enhancement of these particular services reflects global efforts to modify ecosystems to maximize food production in order to meet growing global demands.17

The MA found that over the past 50 years, humans have altered ecosystems at a greater rate and more extensively than at any comparable period of time in the history of mankind.16 The following examples, taken from the MA and a variety of other sources, illustrate the scale of the recent anthropogenic transformation of the world's ecosystems.

• The global area of mangrove habitat and coral reefs has fallen by 35% and 20%, respectively, since 1980.18 The loss of these habitats has resulted in a reduction in their capacity to provide critical services such as coastal storm

protection.16, 19

Table 1. The state of ecosystem services globally

Ecosystem services Degraded Mixed condition Enhanced

Provisioning Freshwater Timber Livestock

Capture fisheries Fibre Crops

Wild foods Aquaculture

Wood fuel

Genetic resources

Biochemicals

Regulating Water purification and waste treatment Air quality regulation Regional and local climate regulation Erosion regulation Pest regulation Natural hazard regulation Pollination Water regulation Disease regulation Carbon sequestration

Cultural Spiritual and religious values Aesthetic values Recreation and ecotourism

Adapted from the MA.1

More land was converted into cropland in the 30 years between 1950 and 1980 than in the 150 years between 1700 and 1850.16 Currently, approximately 24% of Earth's land area has been converted into land for growing crops or rearing livestock.

After an 8-fold increase in the global consumption of nitrogen-based fertilizers between 1960 and 2003, human activities currently produce more biologically available (reactive) nitrogen than is produced by all natural processes combined. ' As much as 50% of nitrogen-based fertilizer applications are lost to the wider environment, with severe consequences such as nutrient loading within freshwater and coastal systems leading to algal blooms that strip oxygen from the water and kill off other aquatic life. Water withdrawals from rivers and lakes for irrigation, industrial and household use have doubled since the 1960s, with far-reaching consequences for the accessibility and flow of freshwater sources in a number of regions. In the same period the quantity of water impounded by dams has quadrupled, and is now estimated to be some three to six times greater than the amount held by natural river channels worldwide. As a result, wetlands have been lost along with their flood prevention and water filtration services, while tens of millions of people have been displaced and many more affected as a result of the loss of habitat and resources that their livelihoods depend upon. 5

Currently 25% of commercially important fisheries are over-exploited.26 Global landings of fish peaked in the 1980s but are now in decline due to stock shortages at a time when the demand for fish has never been as

great.26

The consequences of ecosystem change for human society

The MA highlighted the continued degradation of the world's ecosystems and services as a significant barrier to achieving the Millennium Development Goals of ensuring environmental sustainability and reducing global poverty, hunger and disease.20 It reported that even with the progress achieved by increasing the supply and utilization of some ecosystem services, global levels of poverty remain high and imbalances in access to ecosystem services are growing.16 Moreover, the MA found that the costs of ecosystem service degradation are being consistently and disproportionately felt by the poor, contribute to the widening of social inequalities and are often the primary factor causing poverty and sparking social conflicts.16

Many of the world's ecosystems are close to reaching ecological thresholds ('tipping points') which, if breached, trigger rapid and possibly irreversible changes to the supply of ecosystem services with serious consequences for human wellbeing.16, 27 These changes could include sudden shifts in regional climate, abrupt alterations of water quality, the uncontrolled spread of disease or the collapse of fisheries.

The following sections explain, in sectoral terms, the ways in which ecosystem change and the loss of ecosystem services can impact upon human society.

Health

There is a strong connection between human health and the condition of the Earth's ecosystems. For the world's poorest societies, the preservation of functioning ecosystems is often

a matter of life and death. People starve when fisheries collapse and outbreaks of cholera spread when the wetlands that filter waste and purify water supplies are degraded.28 People in developed nations are also affected by the degradation of the world's ecosystems. For example atmospheric and water pollution have been linked to increases in cancer, heart disease, blue-baby syndrome, asthma and a range of other respiratory problems;16 whilst a warming of the global climate is extending the geographic range of disease carriers such as ticks and mosquitoes, introducing pathogens into naive environments and fuelling the spread of infectious diseases across the planet.29 In addition to provisioning or regulating services, changes to the supply of cultural services can also have a strong impact on health through their influence on spiritual, aesthetic, inspirational and recreational opportunities, which in turn impact upon physical and emotional health and wellbeing.30

production) are often far lower than the values of non-marketed services (such as pollination and watershed protection) that are commonly overlooked when decisions are made about how best to manage environmental assets. For instance, with a discount rate of 6% over 30 years, the total economic value of intact mangrove forests was found to be 72% greater than that of mangroves that had been converted for use in aquaculture.7 The lower total economic value of the converted mangrove forests reflected the loss of sustainably harvested timber and non-timber forest products, tourism and aesthetic benefits, the capacity to capture carbon, a source of dissolved oceanic carbon, revenue from offshore fisheries and coastal protection from storms. The MA estimated that across habitats, the values associated with marketable ecosystems services account for less than 33% of the total economic value of ecosystems when the values of non-marketed services are included.16

Economy

The world's economies depend upon the supply of certain products such as timber, fish, meat and crops. When the ecosystems that supply these products collapse, the damage to the world's economies is clear to see. For example, when the stocks of North Atlantic cod plummeted in the early 1990s due to decades of overfishing, the fallout included the loss of tens of thousands of jobs and cost over $2 billion (USA) in income support and retraining payouts.16 The Gulf of Mexico, at present home to the largest fishery in the USA (both commercial and recreational), is currently threatened by agricultural nitrogen and phosphorous fertilizer runoff flowing into the Gulf from the Mississippi river. These fertilizers stimulate seasonal algal blooms that strip the water of oxygen creating a dead zone of up to 21 000 square kilometres each year in which very little marine life can persist.31

The reduction in the supply of an ecosystem service can be interpreted as the loss of a capital asset.16 However, ecosystem services usually do not appear on decision-making balance sheets because traditional accounting systems do not include measures of resource depletion or the erosion of ecosystem services. Many services such as the purification of water supplies, regulation of floods or supply of aesthetic benefits are not generally seen as market goods. As a result, the benefits that these services supply to society are largely unrecorded. Thus, if a nation cuts down all of its forests and exhausted its fish stocks, this would show up as a positive gain in gross domestic product (GDP), although the nation has lost capital assets on which its future wellbeing and wealth depended. If the indices of the wealth of nations, such as GDP, included estimates of the losses related to the depletion of environmental assets, this would provide a much more balanced assessment of the true wealth of nations.32

Balmford et al.33 reported that the values associated with marketable ecosystem services (such as timber and food

Security

The supply of ecosystem services such as food, freshwater, defence against natural hazards and the regulation of disease underpin our personal and national security.20 When these services are eroded social order and stability disintegrate alongside them, as was demonstrated in the aftermath of the 2005 Gulf hurricanes.34, 35 The MA warns that human activities will increase the likelihood of natural disasters such as floods, wildfires and storms, unless measures are taken to protect ecosystems and lessen societal vulnerabilities by making better informed development

decisions.1, 36, 37 For example, the removal of wetlands

through leveeing, draining and canalization reduces natural flood storage capacity by up to 80% and increases the probability, duration and severity of flood events.16

The depletion of natural resources can also function as a catalyst for war and other confrontations.38 Conflicts involving access to provisioning services like food or freshwater supplies can be found in many parts of the world, bringing severe security risks to these regions. For example, in the Middle East freshwater supplies are being used faster than they are being replenished. The scarcity of freshwater supplies in this region often serves to amplify conflicts, adding to the area's political instability.1, 39

The bottom line

The threats posed by ecosystem collapse may often appear greater in countries that are resource poor. However, the subsequent by-products such as political instability, disease and the migration of refugees can readily span borders.36 The degradation of ecosystems and their services increases risks to public health, and undermines both security and economic stability while threatening the overall ability to sustainably support human society and achieve future development goals.40

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The findings laid out by the MA challenge the logic behind the way that ecosystems and their services are valued within decision-making. The deterioration of ecosystems, increased risks from ecosystem collapse and the worsening of poverty—in particular for resource dependent and poor rural societies —are all rooted within the choices that we make about which development paths and policies to pursue.

Ecosystem services as the link between environment and development

In the past, development goals and environmental management objectives have often been considered in isolation or even in opposition to each other. The two topics are conventionally considered within separate academic fields, different government offices and as a result are often managed in isolation and by different laws and policies. This needs to change. Instead, we need a framework that unites issues of the environment and development, enabling decision-makers to view the two in unison, extending thinking beyond how development affects the environment, to incorporate an understanding of how development in fact depends upon the environment.

Development goals might be focused on, for example, generating more electricity, increasing food production or reducing poverty. In the past, actions to meet these goals have often resulted in the overall degradation of long-term ecosystem service supply. For example, the construction of a dam for electricity production might reduce downstream fish populations, or a regional strategy to develop agriculture might lead to deforestation that resulted in floods and soil erosion. As a result, the success of development goals was often undermined when the resulting degradation of ecosystem services began to affect those who depend upon the environment for their livelihoods and wellbeing.

Whether designing a strategy to increase biofuel production or drafting a coastal expansion plan, including an awareness of ecosystem services can help to strengthen development decisions. The following case studies demonstrate the importance of this understanding when choosing between different development options. The first example highlights how policies based on narrow sectoral objectives, in place of an integrated ecosystem service approach, can have unplanned and costly consequences, while the second demonstrates how the opportunity for investing in the restoration of natural capital and ecosystem services can provide a practical and sustainable solution that meets the needs of development.

Case study: desertification in western China

Desertification currently affects one-third of the world's population.43 Western China is home to the largest conversion of productive land into desert anywhere in the world,

with over 400 000 hectares of land converted each year.44 However, this was not always the case.

In the past, the oasis of Minqin County acted as a barrier to the eastward expansion of the Tengger and Badain Jaran deserts. 5 Early in the 1950s, a national plan aimed at increasing food production was implemented by Chairman Mao. This plan led to the widespread cultivation of large areas of available land with deforestation, wetland reclamation and irrigation projects spreading across the country. However, the resulting consequences for a number of ecosystem services, including the maintenance of the water table by forest ecosystems, have been ruinous. Minqin County's lakes have dried up and the oasis is being gradually engulfed by desert sands, nearby reservoirs are waterless and the remaining supplies of groundwater are predicted to dry up in 15-17 years. The overuse of groundwater resources and the disruption of natural channels and forests that regulate hydrolo-gical flows in the region have resulted in the loss of ecosystem services such as soil formation, with severe health, economic and security consequences as a result. Severe storms now batter Beijing with half a million tonnes of sand each year causing serious health problems, while dust clouds reach as far as Korea, Japan and the west coast of North America. The Chinese government has already spent $9 billion (US) combating the desertification of Minqin County through reforestation programmes, the replanting of desert vegetation, decommissioning dams and imposing bans on deforestation and grazing. 7' The mounting costs now include financing the relocation of entire villages of ecological refuges.49' 50

Many of the desertification problems facing China today are a direct result of the short term and singularly focused decisions made in the 1950s to increase food production. These problems could have been avoided by taking a more holistic look at the region's ecosystems, and by considering all of the services that these ecosystems supply across a range of geographical scales and longer term time frames. Such an approach could have helped to identify ecosystem service-based vulnerabilities and allow decision-makers to plan accordingly. For example, a review of Chairman Mao's agricultural expansion plan would have highlighted the long-term risks raised by deforestation coupled with the diversion of rivers to irrigate fields. A more informed policy could have left some forested areas intact to allow farmers to benefit from the role that forests play in maintaining the water table and regulating local climates. Other measures that could have been implemented to mitigate the risks include seasonal grazing bans, monitoring and limiting water withdrawals for use in irrigation and the planting of legumes to fix nitrogen as part of crop rotation cycles.

Case study: New York city's watershed filtration services

New York city's 9 million inhabitants obtain 90% of their drinking water supplies from the Catskill and Delaware

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watersheds, situated 130 miles outside the city, which filter water through the ecosystem's waterways and wetlands.5 Altogether, these regions cover an area of around 1500 square miles and support over 75 000 residents. Historically these watersheds provided very high quality drinking water, but by the late 1980s they became degraded through a combination of land conversion, development and negligence that resulted in sewage and agricultural runoff polluting the waterways.5 However, instead of building a water filtration plant with estimated construction costs of $6-8 billion (US) and a further $300 million (US) in annual operating costs,53 the municipal government opted to invest in restoring the Catskill and Delaware watersheds. The cost of restoring the health of these watersheds, and therefore their water filtration services, was only $1 -1.5 billion (US).51

This decision amounted to investing in natural capital in place of physical capital, with the understanding that if correctly managed the watersheds could provide the same filtration services as the proposed water filtration plant, but for a fraction of the cost.5 The restoration efforts included rewarding farmers who adopted best management practices, compensating landowners for restrictions on private development and subsidizing improvements to septic treatment systems.5 ' 55 By investing in the restoration of the watershed's capacity to filter water, additional services including carbon capture and flood prevention as well as recreational and cultural benefits were provided at no extra cost. The restoration of the Catskill and Delaware watersheds has acted as a model for other municipalities such as Rio de Janeiro

in Brazil.56

The municipal government recognized the strong two-way connections that link the natural and human systems in New York City and the surrounding watershed catchment area. The success of their decision can be attributed to the way that they thought holistically in terms of ecosystem management, assessing the variety of services that are supplied by the environment, and by acknowledging the importance of understanding the underlying tradeoffs between these services when it comes to choosing between different uses of environmental assets. The Catskill watershed example demonstrates that decision-makers can make informed choices that recognize the central role that strong and functioning ecosystems play in successfully and sustainably achieving development goals and supporting human society.

An ecosystem service approach to decision-making

The successful realization of development goals—from constructing an agribusiness export sector, to expanding infrastructure or reducing malnourishment and poverty—both depends on and impacts the supply of ecosystem services.

By failing to take account of the links between ecosystem services alongside society's overall dependence upon their supply, decision-makers risk irreparably weakening the environmental infrastructure and support systems upon which all societies depend.57 A more sustainable future requires a different approach to the way decisions are made about the use of nature's resources, one where the benefits and services provided by ecosystems are understood, evaluated and appropriately represented within the decision-making arena.

Although the challenges that we face are substantial, they are not insurmountable. The MA began the process, by sowing the seeds of change and offering decision-makers a new way of viewing and valuing the world's ecosystems and their contribution to human wellbeing. It is now time to build upon this foundation and develop decision-making frameworks that hold the protection of ecosystem services, and the successful realization of development objectives as mutually reinforcing sides of the same coin. However, progress towards this goal will be limited until we address existing deficits in our understanding of ecosystem services.

The ecosystem service research agenda

The fundamental challenge facing scientists and decision-makers is to better understand the dynamic relationships between ecosystem services and human wellbeing in relation to the changing influence of multiple direct and indirect drivers. New research is needed that evaluates the suite of feedbacks and processes across biophysical, ecological and social systems in order to better recognize and manage the relationship between human societies and the ecosystems upon which they depend.

Work is still needed to help us understand the ecological underpinnings of ecosystem service supply. For example, new research should attempt to quantify the ecosystem characteristics (habitats, communities, populations and species composition, etc.) required to supply individual or groups of ecosystem services. This research could help us to understand the limits of ecosystem service supply, exploring whether ecological prerequisites—in terms of species composition or habitat area, etc.—can be identified that facilitate the provision of particular ecosystem services. Equally, we must also improve our ability to predict the presence of ecological 'tipping points', and to choose between strategies in order to lessen the risks faced by breaching them. Unfortunately, the way that societies and the biosphere interact with each other is not something that can be effectively tested experimentally. However, decision-makers can learn a great deal from the use of models, by reviewing case studies where sudden and irreversible changes have occurred in the past, and by retrospectively considering the management options that might have helped to identify and avoid breaching the 'tipping points'.57 For example, in the case of fisheries, by implementing a

continuous monitoring programme of fish stocks and adapting catch quotas accordingly, managers are more likely to enhance the sustainability of fisheries and avoid collapse than if fixed annual catch limits are implemented.5 Improving our understanding of ecosystem dynamics and the complex interactions supporting ecosystem service supply is fundamental to efforts to improve the long-term sustainability of environmental management decisions.

In order to make sustainable and well-informed decisions about the use of environmental assets, we need to understand how various drivers are affecting the supply of ecosystem services, and to build tools that can be used to explore how these drivers could alter ecosystem service supply in the future. This research should inform management strategies, as we learn more about the resilience and resistance of different ecosystems to a range of natural and human stresses. Increasingly, integrated assessment models, which combine ecological, social and economic data are being used to investigate changes in ecosystem service supply and demand, in response to varying pressures from drivers across local, regional and global scales.59 These models are of limited use when used in isolation. However, when incorporated into scenario-planning exercises, they can provide a quantitative basis upon which to frame inclusive discussions on the importance of various factors in shaping the future. This helps decision-makers to uncover the risks and opportunities presented by alternative options and to minimize any unintended consequences. Therefore, future efforts should focus on developing policy tools and decision support systems capable of dealing with the uncertainties associated with scenario-planning and assessing resultant trade-offs.

Future research should also identify suitable scales at which to study different ecosystem services, which in turn can help inform decision-makers about the most appropriate scales to target management strategies. In line with this, research should also be targeted at developing techniques, which allow us to upscale local impacts and management responses to wider geographical and temporal horizons. Work such as this can help us to address the mismatch between the scales at which ecological and human systems organize when governing at the interface of the two. Human systems traditionally exist within geopolitical and national boundaries, and their goals are often evaluated using short-term measures of success. Ecological processes on the other hand operate on much longer timescales and are not constrained by anthropocentric boundaries. Understanding what institutions, incentives and regulatory mechanisms are effective in preserving and managing the supply of ecosystem services will be essential in ensuring the long-term sustainability of management decisions.

Our understanding of ecological interactions and balances will always be incomplete, and the dynamic relationship between social and ecological systems will continue to change. Reducing the unintended and costly damage to

ecosystems and the services they supply, while continuing to use them in order to develop human wellbeing worldwide will be a long-term and spatially complex experiment that will require continuous innovation and learning as part of an adaptive approach to research and management. Single discipline approaches can lead to an incomplete and inaccurate understanding of the issues involved. For that reason the gaps in our understanding cannot be filled through uncoordinated research into individual components by isolated disciplines. Instead, there is a need for an integrated trans-disciplinary approach to research that successfully bridges disciplines, builds on existing strengths and develops new areas of understanding that are necessary for building resilient socio-ecological systems.

Conclusion

In order to protect the ecosystems upon which mankind depends, we need to change the way that natural resources are thought about and managed within decision-making areas. We need to understand that development trajectories that degrade ecosystems and impair their ability to provide services can, and often do, create long-term costs to human society that greatly exceed short-term, single sector gains. Although these costs are generally ignored by conventional methods of accounting, they are real nonetheless and are borne by society at large. A sustainable future is likely to be one in which individuals and institutions appreciate ecosystems as vital assets, identify the critical role that healthy, functioning ecosystems play in supporting human wellbeing and where the many values of ecosystems are routinely included in decision-making situations. These changes may well be politically controversial and difficult to deliver but the case for decisive and concerted action has never been stronger.

Author biography

Joseph Hancock is a 22-year-old Biology graduate who studied at the University of St Andrews to obtain a first class BSc. (Hons) degree. Joseph is particularly interested in investigating issues at the interface of science and society and in the future he aims to work in the field of international development, exploring the interdependencies between the environment and development.

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