CONTENTS

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Sustainable development and human well-being . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Ecosystem services and the Millennium Ecosystem Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
The nature and scope of ecosystem services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2 The ecosystem approach and water security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Freshwater resources and human impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Sustainable ecosystem services and Integrated Water Resources Management (IWRM) . . . . . . . . . . . . . . . . . . . . . . . . 14
An ecosystem approach to water resources management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Facilitating water security and properly functioning ecosystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3 Water security and ecosystem services case studies: lessons learned . . . . . . . . . . . . . . . 19
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Lessons learned from case studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
　Habitat rehabilitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
　　1. Aral Sea (Central Asia) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
　　2. Chilika Lake (India) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
　　3. Lake Hornborgasjon (Sweden) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
　　4. Delavan Lake (USA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
　　5. Lower Danube River and Danube Delta (Southeast Europe) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
　Pollution control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
　　Hartbeespoort Dam (South Africa) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
　Environmental flows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
　　1. Rouse Hill Recycled Water Area (Australia) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
　　2. Kelly Lakes (USA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
　Enhancing stakeholder involvement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
　　Lakes Osmansagar and Himayatsagar (India) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
　Integrated watershed management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
　　1. Bermejo River (Bolivia, Argentina) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
　　2. Southern Africa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
　　　A. Southern African Development Community . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
　　　B. Okavango River Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
　　　C. Okavango Delta Management Plan (ODMP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
　　3. Panama Canal Watershed (Panama) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
　　4. Bang Pakong River (Thailand) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
4 Response options on water security for sustainable ecosystem services . . . . . . . . . . . . . . 47
Consider ecosystem services and water security early in economic development activities . . . . . . . . . . . . . . . . . . . . . . 48
IWRM must balance ecosystems services to be most effective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Undertake activities directed to enhancing ecosystem services via water security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Rehabilitate degraded ecosystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Undertake appropriate ecosystem monitoring activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Adaptive management to accommodate changing ecosystem management goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Develop partnerships to promote management of balanced ecosystem services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Utilize global venues to promote management of balanced ecosystem services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Establish coherent ecosystem services goals and activities within the UN organizations . . . . . . . . . . . . . . . . . . . . . . . . 50
Enhance public awareness about ecosystem services and water security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

FOREWORD

We live in a world of ecosystems . and our existence would not be possible without the life-supporting services they provide. Properly-functioning ecosystems in turn are fundamentally related to water security. This report, although brief in content, is meant to serve as food for thought about
the linkages and interactions between human survival and well-being, and about the ecosystem services and water security that result from these linkages and interactions. This complex topic requires discussion at many levels of government, society and science. Continuing experience around the world, however, highlights the fact that water security and ecosystem services must be viewed with the same degree of importance in national development programmes as do social welfare a d economic growth. These considerations are also relevant to achieving the targets outlined in the Millennium Development Goals (MDGs). Unfortunately, however, the results of the Millennium Ecosystem Assessment clearly illustrate that we are failing to recognize these linkages and ensure their sustainability. Instead, humanity is continuing to overexploit and pollute ecosystems throughout the world, and at all scales.

This report makes the link between sustainable development and ecosystem services, highlighting that the former is not possible without the latter. Economic development in turn requires an adequate natural resources base, and humans are constantly engaged in activities to access these
resources. The dilemma is that the activities involved in accessing and using these resources, although directed to beneficial uses, also have the potential to negatively impact the very ecosystems that provide them in the first place. Thus, activities that result in ecosystem degradation can be significant constraints to sustainable development.

The role of water security in addressing ecosystem sustainability is fundamental to this goal. As discussed in this report, continued provision of ecosystem services for human welfare and economic development is dependent on properly-functioning and sustainable ecosystem services. Further, water security is at the core of sustainable ecosystem management,.. The dual goal of ecosystem sustainability and water security must be pursued vigorously and in a timely manner, since it could take decades before we master the political, institutional and technical aspects
that enable humanity to use the full potential of ecosystem management for water security. This report is meant to highlight this reality, and to provide examples of cases in which various measures were used to facilitate ecosystem sustainability and water security. Although only providing a
brief discussion of these important issues, it is hoped this report will provide the impetus necessary for governments, non-governmental organizations, industry, agriculture and other ecosystem services stakeholders to consider such issues in addressing both our short-term needs and our long-term goals.

Achim Steiner
Under Secretary General of the United Nations
and Executive Director of UNEP

Introduction

Sustainable development and human well-being
Sustainable economic development has become an encompassing goal of the international community, and at the national level, as a means of improving the health and well-being of citizens over the long term. Achieving sustainable development at any level, however, remains a daunting task, and underpins the targets identified in the Millennium Development Goals. These targets are many and diverse, addressing basic human health issues such as hunger, poverty, education and health. At the same time, however, these targets are also directly or implicitly related to the health and sustainability of our ecosystems, upon which the target of sustainable development rests. Many factors, including scarce financial and human resources, fragmented authority and responsibility, and lack of political will, remain formidable obstacles to sustainable development. The greatest impediment to achieving sustainable development, however, is depletion and degradation of natural resources, which represent the essential ingredients for human survival, and the ‘fuel’ and building blocks for human well-being and economic development. The long-term sustainability of
ecosystems is critical, therefore, since they are the ultimate source of these resources.

Ecosystem services and the Millennium Ecosystem Assessment
We live in a world of ecosystems. Simply stated, an ecosystem is a complex of living organisms (plants, animals, microorganisms) and their non-living surroundings (water, soil, minerals). These living (including humans) and nonliving components are linked as a functional unit by an
incredibly complex series of interactions and processes that impact the status of both groups of components. Further, ecosystems provide a range of services to humans, including provisioning, regulating, supporting and cultural, without which our survival and well-being would simply not be possible.

This document was developed as a follow-up to address the findings of the Millennium Ecosystem Assessment (MA). The MA, begun in June 2001, was a four-year international work programme to provide decision-makers with scientific information on the links between ecosystem changes and
the well-being of humans. An ideal economic development scenario would be one in which humanity interacted with ecosystems with the guiding principle that of sustaining their services rather than presiding over their continuing degradation. It also would include recognition of the
inseparable connections between humans and ecosystems. The interactions between humans and the ecosystems that surround them control their health and vitality. Unfortunately, however, the MA reported that 60% of the ecosystem services accessed are in decline, with the main drivers of this decline being anthropogenic in nature. More precisely, it is human-environment interactions that result in the greatest
disturbances or imbalances in the structure or function of ecosystems.

It is easy to say that we must take care of our ecosystems. Experience from around the world, however, clearly indicates that we continue to degrade or over-exploit ecosystems to meet our natural resource needs, whether by the very poor to meet simple survival needs or by the more affluent to satisfy an increasing appetite for material goods. There is virtually no place on our planet isolated from the potential impacts of human activities. Climate change, for example, is a global-scale phenomenon affecting our entire world.

Persistent synthetic organic pollutants exist in measurable quantities in the fatty tissues of seals and other organisms at the earth’s poles. Pollutants from industrial activities in one location can travel long distances from their source to impact ecosystems in other locations. Examples of human use (and misuse) of our natural capital (resources) abound, including polluted rivers, lakes and wetlands, depleted groundwater aquifers, erosion and loss of productive land, deforestation, desertification, decreased biological diversity, etc.

The drivers of environmental degradation and overexploitation are numerous, multifaceted and synergistic in impact. As highlighted in the 3rd World Water Development Report, many important environmental drivers actually exist outside the domain of ‘the environment’. As examples,
significant environmental change drivers include population growth and human migration from one location to another, resulting in a range of environmental stresses. Social drivers range from activities of the very poor to meet simple survival needs, to unsustainable production and consumption patterns in developed nations, both with their related environmental stresses. Technological advances represent a double-edged sword in that they can be rapid in application and impact. An example is improved water conservation, processing and re-use technology, as well as increased agricultural and industrial productivity associated with existing water resources.

On the other hand, the emergence of biofuels has led to an unanticipated use of water resources for crop production, with consequences for grain production patterns and water resource needs. Laws, policies and institutions represent governance elements, whether directed at environmental
issues in general, or water security in particular. Further, climate change represents a global-scale consequence of human actions, attributed by many to the impacts of the excessive and unsustainable use of fossil fuels for transportation and energy production. In fact, humans can
claim to be the most ‘successful’ species on our planet in that they are the most capable of significantly changing the natural environment by engaging in activities to meet their resource needs. This is the basis for some to view the environment as something to be conquered to meet human needs, in contrast to the role of humans as stewards of the environment, ensuring its sustainable use (Brinkman and Pedersen, 2000).

Human survival is completely dependent upon the continued flow of ecosystem services. Some countries have the resources, both human and financial, and technology to address the immediate impacts of ecosystem changes. These resources are not infinite, however, and their utilization
comes with an environmental price tag, substantial in some cases. Over-exploitation (depletion of supply) and degradation (depletion of quality) are two aspects of the price to pay, with the causes ranging from economic growth to demographic changes, and even individual choices. Thus, recognition of the limits of nature to provide these services at the pace needed to meet human demands is critical, although often ignored or subordinated, in national economic development plans and programs.

The nature of ecosystem services
Ecosystem services represent the benefits that humans obtain from ecosystems. These services are both direct and indirect in nature, some easily recognized and others more subtle. And human well-being is fundamentally dependent upon all these services. As noted in the MA
(2003), changes in these services can affect humanity, sometimes dramatically, with negative impacts on security, basic materials for human health and well-being, and the maintenance of social and cultural relations.

By way of illustration (Figure 1), ecosystem provisioning services encompass the products obtained from ecosystems, including food, freshwater, timber and fuel wood, fibres and genetic resources, while non-material benefits obtained from ecosystems comprise cultural services, including recreation, transport, ecotourism, spiritual, religious and aesthetic uses, education, cultural heritage, and a ‘sense of place. Ecosystem regulation
services includes the benefits to be derived from the role of the environment in climate regulation, flood alleviation, water purification, and disease regulation. supporting services underlie the sustainability of all the above-noted services, including nutrient cycling, soil formation and primary
production.

The MA assessed ecosystem changes within the context of several determinants and constituents of human wellbeing. These include: (1) security . referring to the strength of the social structure of a community, and to its material well-being, both of which can be influenced by changes

Figure 1. Linkages between ecosystem services and human well-being.（略）

in provisioning and cultural services; (2) basic material for human well-being - which can be influenced both by provisioning (food, fibre, etc.) and regulating services such as water purification; (3) human health - which is influenced both by provisioning services (food production), regulating services, particularly those that can influence the distribution of disease vectors, pathogens, etc., and also cultural services such as spiritual benefits and recreation; and (4) social relations . the quality of human experiences, influenced primarily by the cultural services. All these
determinants are underpinned by so-called ‘freedoms and choices,’ which can be influenced by changes in all the above-noted services (MA, 2003).

The range of services provided by different ecosystems is illustrated in Figure 2, which also highlights the distinction on one hand, and the continuity on the other hand, of theseservices (MA, 2005b). Although these services are not　routinely valued or costed in financial terms, their estimated　cumulative economic value on a global scale is enormous.

Figure 2. Ecosystems and their representative ecosystem services（略）

In an often-cited example, Costanza et al. (1997) provided an estimate of the value of the world’s ecosystem services and natural capital, and the benefits to be derived from them. Based on their work, the estimated economic value of 17 ecosystem services provided by 16 biomes averaged
US$ 33 trillion per year. The aquatic biomes examined in their study (both marine and freshwater) made up about US$ 27 trillion of this total estimate. This compares to a total GDP, of all the countries in the world combined, of approximately US $17 trillion during the study period.
Although some assumptions used in determining the economic value of specific ecosystem services in the study have been questioned, there is no doubt that the total value of ecosystem services provided to humanity totals in the tens of trillions of dollars annually.

Against this background, the MA reached a number of important conclusions regarding ecosystem changes on a global scale, many with distressing long-term implications (MA, 2005a). Fifteen (60%) of the 24 ecosystem services examined in the MA are being used in an unsustainable manner, resulting in pollution, degradation and overexploitation. Further, human-induced ecosystem changes are increasing the possibility of non-linear changes in ecosystems (e.g., accelerating or reversing trends) with potentially significant consequences regarding their ability to provide life-supporting ecosystem services to humanity. This observation highlights the great responsibility of natural resource managers to secure the resilience of ecosystems.

In addition, to meet growing demands for freshwater, food, fibre, fuel, etc., humans have changed ecosystems more rapidly and more extensively during the past half-century than ever before. Although these changes have contributed to human well-being and economic development, they
also have resulted in substantial ecosystem degradation in many locations. They have reduced global biodiversity, as well as exacerbated the poverty of some groups of people, particularly the rural poor who often depend directly on ecosystem services for their economic survival and
livelihoods.

Even more significant was the conclusion that the demand for ecosystem services around the world is now so great that trade-offs between ecosystem services (e.g., conversion of forests to agricultural land, with attendant gains in some ecosystem services at the expense of perhaps even more important supporting or regulating services) are becoming increasingly necessary. Assuming a continuing trend in this direction, the MA concludes that future generations will experience a substantial reduction in the human benefits to be derived from these ecosystem services. It also means that future efforts may have to be directed to balancing between ecosystem services in some locations and under some ircumstances, particularly when they are being overexploited or degraded.