12.pdf

ECOSYSTEM SERVICES ECOSYSTEM SERVICES

ECOSYSTEM SERVICES

Ecosystem services in decision making:

time to deliver

Gretchen C Daily 1* , Stephen Polasky 2 , Joshua Goldstein 1 , Peter M Kareiva 3 , Harold A Mooney 1 , Liba Pejchar 1 ,

Taylor H Ricketts 4 , James Salzman 5 , and Robert Shallenberger 6

Over the past decade, efforts to value and protect ecosystem services have been promoted by many as the last,

best hope for making conservation mainstream – attractive and commonplace worldwide. In theory, if we can

help individuals and institutions to recognize the value of nature, then this should greatly increase investments

in conservation, while at the same time fostering human well-being. In practice, however, we have not yet

developed the scientific basis, nor the policy and finance mechanisms, for incorporating natural capital into

resource- and land-use decisions on a large scale. Here, we propose a conceptual framework and sketch out a

strategic plan for delivering on the promise of ecosystem services, drawing on emerging examples from

Hawai‘i. We describe key advances in the science and practice of accounting for natural capital in the decisions

of individuals, communities, corporations, and governments.

Front Ecol Environ 2009; 7(1): 21–28, doi:10.1890/080025

T he Millennium Ecosystem Assessment (MA)

mental wing of Goldman Sachs; Daily and Ellison 2002;

Bhagwat and Rutte 2006; Kareiva and Marvier 2007;

Ostrom et al . 2007; Goldman et al . 2008). China, for

instance, is investing over 700 billion yuan (about

US$102.6 billion) in ecosystem service payments, in the

current decade (Liu et al . 2008).

The goal of the Natural Capital Project – a partnership

between Stanford University, The Nature Conservancy,

and World Wildlife Fund (www.naturalcapitalproject.org)

– is to help integrate ecosystem services into everyday

decision making around the world. This requires turning

the valuation of ecosystem services into effective policy

and finance mechanisms – a problem that, as yet, no one

has solved on a large scale. A key challenge remains: rel-

ative to other forms of capital, assets embodied in ecosys-

tems are often poorly understood, rarely monitored, and

are undergoing rapid degradation (Heal 2000a; MA

2005; Mäler et al . 2008). The importance of ecosystem

services is often recognized only after they have been lost,

as was the case following Hurricane Katrina (Chambers

et al . 2007). Natural capital, and the ecosystem services

that flow from it, are usually undervalued – by govern-

ments, businesses, and the public – if indeed they are

considered at all (Daily et al . 2000; Balmford et al . 2002;

NRC 2005).

Two fundamental changes need to occur in order to

replicate, scale up, and sustain the pioneering efforts that

are currently underway, to give ecosystem services weight

in decision making. First, the science of ecosystem ser-

vices needs to advance rapidly. In promising a return (of

services) on investments in nature, the scientific commu-

nity needs to deliver the knowledge and tools necessary to

forecast and quantify this return. To help address this

challenge, the Natural Capital Project has developed

InVEST (a system for Integrated Valuation of Ecosystem

advanced a powerful vision for the future (MA

2005), and now it is time to deliver. The vision of the

MA – and of the prescient ecologists and economists

whose work formed its foundation – is a world in which

people and institutions appreciate natural systems as vital

assets, recognize the central roles these assets play in sup-

porting human well-being, and routinely incorporate

their material and intangible values into decision mak-

ing. This vision is now beginning to take hold, fueled by

innovations from around the world – from pioneering

local leaders to government bureaucracies, and from tra-

ditional cultures to major corporations (eg a new experi-

In a nutshell:

• Valuing nature is central to mainstreaming conservation, but is

not an end in itself

• Success hinges on a better understanding of ecosystem produc-

tion functions and on integrating research (and experimenta-

tion) into the development of new policies and institutions

• The Natural Capital Project is designing practical tools for this

purpose, including InVEST, a system for quantifying ecosystem

services produced under different scenarios

• The use of these tools in contrasting settings is opening up

important conservation opportunities

1 Center for Conservation Biology (Department of Biology) and Woods

Institute for the Environment, Stanford University, Stanford, CA

* (gdaily@stanford.edu); 2 Applied Economics and Ecology, Evolution

and Behavior, University of Minnesota, St Paul, MN; 3 The Nature

Conservancy, Seattle, WA; 4 Conservation Science Program, WWF-

US, Washington, DC; 5 Nicholas School of Environment and Earth

Sciences, Duke University, Durham, NC; 6 The Nature

Conservancy, Kamuela, HI

www.frontiersinecology.org

Ecosystem services in decision making

GC Daily et al.

Panel 1. A tool for Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST)

The Natural Capital Project (www.naturalcapitalproject.org) is a partnership

between Stanford University, The Nature Conservancy, and World Wildlife

Fund, working together with many other institutions. The Project’s mission is

to align economic forces with conservation, by developing tools that make

incorporating natural capital into decisions easy, by demonstrating the power

of these tools in important, contrasting places, and by engaging leaders globally.

The Project is developing a software system for quantifying ecosystem ser-

vice values across land- and seascapes, called InVEST. This tool informs man-

agers and policy makers about the impacts of alternative resource manage-

ment choices on the economy, human well-being, and the environment, in an

integrated way.

Staging

Scenarios

( Management, climate, population)

Models

Provisioning

Food

Timber

Fresh water

Regulating

Climate

stability

Flood

control

Cultural

Recreation

Tradition

Community

Biodiversity

Species

Habitats

Supporting

Pollination

Outputs ~ Biophysical, economic, cultural

Tradeoff

curves

Balance

sheets

Examples of urgent questions that InVEST can help answer include:

• How does a proposed forestry management plan affect timber yields, biodi-

versity, water quality, and recreation?

• Which parts of a watershed provide the greatest carbon sequestration, biodi-

versity, and tourism values? Where would reforestation achieve the greatest

downstream water quality benefits?

• How would agricultural expansion affect a downstream city’s drinking water

supply? How will climate change and population growth impact these effects?

Maps

Figure 1. An iterative process for integrating ecosystem

services into decisions. The process begins with stake-

holder engagement around impending decisions, with a

focus on realistic, alternative scenarios for the future.

The modeling is shaped by stakeholders, and typically

focuses on the (subset of possible) services and scenarios

deemed most important. Outputs are displayed in

accordance with stakeholder preferences, in the form of

maps, tradeoff curves, and/or balance sheets. These

can be expressed in biophysical (eg tons of carbon),

economic (eg dollars), or cultural (eg visitor-days)

terms (see Nelson et al . page 4 in this issue).

InVEST is designed for use as part of an active decision-making process

(Figure 1). The first phase of the approach involves working with decision mak-

ers and other stakeholders to identify critical management decisions and to

develop scenarios to project how the provision of services might change in

response to those decisions, as well as to changing climate, population, and so

forth. Based on these scenarios, a set of models quantifies and maps ecosystem

services. The outputs of these models provide decision makers with informa-

tion about costs, benefits, trade-offs, and synergies of alternative investments in ecosystem service provision. A detailed case study of the

Willamette Valley, OR, is given in Nelson et al . (page 4 in this issue).

InVEST uses a flexible, modular, and “tiered” modeling approach to ensure that the models are useful worldwide, including in places with

sparse data.Tier 1 models have modest data requirements to estimate the relative production of ecosystem services across a landscape, and

can inform prioritization exercises and general management planning.Tier 2 models compute absolute service levels and corresponding eco-

nomic values, to support more information-rich planning processes, such as payment for ecosystem services schemes. Finally,Tier 3 inte-

grates more complex models, developed by other research teams (eg hydrology models), that include time steps and feedbacks in the over-

all ecosystem service analysis.

Services and Tradeoffs; see Panel 1 and Nelson et al . page

4 in this issue). Second, ecosystem services must be explic-

itly and systematically integrated into decision making by

individuals, corporations, and governments (Levin 1999;

Heal 2000a; NRC 2005). Without these advances, the

value of nature will remain little more than an interesting

idea, represented in scattered, local, and idiosyncratic

efforts.

Here, we propose a framework that considers a number

of services simultaneously. It does so over scales appropri-

ate to local-, regional-, and national-level resource-man-

agement decisions; it connects the science of quantifying

services with valuation and policy work to devise payment

schemes and management actions; and it helps in the

replication and scaling up of successful models, thereby

creating confidence and providing inspiration for future

initiatives. We also highlight the advances in research and

implementation that will be necessary to take this

approach forward (see also Carpenter et al . in review).

We draw upon experiences from Hawai‘i to illustrate

each step in our framework. Hawai‘i is a microcosm of the

important forces at play worldwide. As a result of a rapidly

growing population and intensifying development pres-

sure, the future of Hawaii’s forests, croplands, and ranch-

lands is in question, as are other aspects of its economy and

culture. There is, however, renewed appreciation for tradi-

tional Hawaiian land management, in which watersheds

are recognized for all the goods and services they produce,

from the mountains to the sea. Today, diverse leaders across

the public, private, and non-profit sectors are mobilizing to

incorporate the values of natural capital into land-use and

policy decisions. By highlighting some of the active works-

in-progress there, we illustrate the promise and challenge

of creating the broader institutional and cultural changes

that are needed worldwide.

What’s new?

An appreciation of ecosystems as valuable capital assets

traces back to Plato, or even earlier (Mooney and Ehrlich

www.frontiersinecology.org

GC Daily et al.

Ecosystem services in decision making

1997), and the current research agenda on

ecosystem services continues a long-standing

field of inquiry. For example, renewable

resources have been an active area of study

since at least the 1950s, when Gordon

(1954) first characterized the problems of

open-access fisheries. In the 1960s and

1970s, economists set out to measure “the

value of services that natural areas provide”

(Krutilla and Fisher 1975); they focused on

agricultural production (Beattie and Taylor

1985), renewable resources (Krutilla 1967;

Clark 1990), non-renewable resources

(Dasgupta and Heal 1979), and environmen-

tal amenities (Freeman 1993). More recent

advances have been seen in a broad range of

areas, including ecology and global change,

economics, institutions and policy, and espe-

cially their integration (eg Dasgupta 2001;

MA 2005; NRC 2005; Ruhl et al . 2007).

Yet, ascribing values to ecosystem goods

and services is not an end in itself, but rather

one small step in the much larger and dynamic arena of

political decision making (Daily et al . 2000). Our chal-

lenge today is to build on this foundation and integrate

ecosystem services into everyday decisions. This requires

a new focus on services beyond provisioning services; an

understanding of the interlinked production of services; a

grasp of the decision-making processes of individual

stakeholders; integration of research into institutional

design and policy implementation; and the introduction

of experimentally based policy interventions designed for

performance evaluation and improvement over time.

There are a lot of devils in the details of this work.

Decisions

Actions and

scenarios

Incentives

Institutions

Ecosystems

Biophysical

models

Information

Values

Services

Economic and

cultural models

Figure 2. A framework showing how ecosystem services can be integrated into

decision making. One could link any two ovals, in any direction; we present the

simplest version here.

right institutions can create incentives, so that the deci-

sions made by individuals, communities, corporations,

and governments promote widely shared values. The

links between the “values”, “institutions”, and “decisions”

ovals are much more representative of the art and politics

of social change than of science, although scientists can

inform these debates if they concentrate on specific deci-

sions and are attuned to the social and political contexts.

In the following sections, we move around the

schematic of Figure 2 to explore how a focus on decisions

can motivate the integration of ecosystem services into

management and policy decisions, and inspire a research

agenda to support this change.

Making ecosystem services operational

Figure 2 presents a framework for the role that ecosystem

services can play in decision making. Although the

framework is shown as a continuous loop, we start with

the “decisions” oval to emphasize our focus. The main

aim in understanding and valuing natural capital and

ecosystem services is to make better decisions, resulting

in better actions relating to the use of land, water, and

other elements of natural capital.

The biophysical sciences are central to elucidating the

link between actions and ecosystems, and that between

ecosystems and services (biophysical models of “ecologi-

cal production functions”). The social sciences are cen-

tral to measuring the value of services to people (“eco-

nomic and cultural models”). Because this value is

multidimensional, it makes sense to characterize it as

fully and systematically as possible, in ways that will be

meaningful to many different audiences.

Finally, valuing ecosystem services provides useful

information that can help design the institutions that

will guide resource management and policy. Having the

Decisions

ecosystems

In Figure 2, the science needed to inform the link that

connects decisions and ecosystems is a huge challenge in

itself. We do not detail this here, since readers of Frontiers

have built a vast literature connecting past human deci-

sions and activities to their impacts on ecosystems and

landscapes, and the species that inhabit them. Looking

forward is also essential, however, and scenarios that

describe plausible futures, combining alternative deci-

sions with projected changes in demographics, climate,

and other factors, have become both more common and

more sophisticated (eg Peterson et al . 2003).

In Hawai‘i, there has been extensive work on how

land-management decisions affect ecosystems. For exam-

ple, we have learned that the decision to introduce

exotic pasture grasses has dramatically changed fire fre-

quency and intensity across landscapes (D’Antonio and

Vitousek 1992), and that the introduction of cattle, non-

native game, and feral ungulates has further transformed

www.frontiersinecology.org

Ecosystem services in decision making

GC Daily et al.

requires a focus on different questions than are

traditional in ecology (Boyd and Banzhaf

2005). The MA synthesizes our existing

knowledge (MA 2005), often at the global

scale. There are also many fine-scale studies of

ecosystem production functions, typically

focusing on a single service (Kremen et al .

2002; Ricketts et al . 2004; Jackson et al . 2005;

Hougner et al . 2006). Much more work is

needed now, on integrating multiple services

at regional and global scales (eg Nelson et al .

page 4 in this issue; Chan et al . 2006; Naidoo

and Ricketts 2006; Brauman et al . 2007).

In Hawai‘i, as in most places, ecological pro-

duction functions are largely undescribed.

However, efforts are now underway to quantify

production functions for a range of policy-rele-

vant ecosystem services, in fine detail, across

heterogeneous landscapes, and to elucidate

the tradeoffs and synergies among services

under alternative management options.

Historically, the production of goods through

ranching and forestry has been the best

described of terrestrial services. Today, there is

growing interest in managing forests of the

endemic hardwood Acacia koa as a “win–win”

land use, providing high-value timber as well

as other ecosystem services (eg Pejchar et al .

2005; Goldstein et al . 2006; Litton et al . 2006;

Scowcroft et al . 2007). Multiple reforestation

projects – some spanning thousands of acres – have

recently been launched, allowing further research on pro-

duction functions for services such as carbon sequestration

(eg Litton et al . 2006; Scowcroft et al. 2007) and ground-

water recharge (K Brauman unpublished data; Figure 3).

The translation of ecosystem condition and function

into ecosystem services requires interdisciplinary and user-

oriented research, including: (1) collaborating with stake-

holders to define services that people care about (eg

Carpenter et al . 2006; Cowling et al . 2008); (2) developing

transparent, flexible models of ecological production func-

tions at scales relevant to decision making (Panel 1); and

(3) testing and refining these models in systems around the

world, to derive general insights (eg Ricketts et al . 2008).

Figure 3. A micrometeorological station for quantifying the roles of pasture

and nearby forest in recharging groundwater supplies for local water users.

Palani Ranch, Kona, Hawai‘i.

native ecosystems (Cuddihy and Stone 1990; Maguire et

al . 1997). Conservation and restoration are a key focus

today (Manning et al . 2006; Goldstein et al . 2008), as are

new remote sensing systems for characterizing biodiver-

sity and ecosystem structure and function at large scales

(Asner et al . 2008).

The scientific foundation for informing decisions that

affect ecosystems could be greatly enhanced by: (1) col-

laborating with stakeholders to define important scenar-

ios of alternative future uses of land, water, and other nat-

ural resources (eg MA 2005, “Scenarios” volume); (2)

improving methods for assessing the current condition,

and predicting the future condition, of ecosystems (eg

Heinz Center 2008); and (3) establishing state-of-the-art

programs for long-term monitoring of biodiversity and

other ecosystem attributes (eg Scholes et al . 2008).

Services

values

The promise of ecosystem service analyses is that they

will make explicit the costs and benefits of alternative

actions to people (NRC 2005). Economic valuation

methods take changes in the supply of ecosystem services

as input and translate these into changes in human wel-

fare, in monetary terms (Repetto et al . 1987; Daily et al .

2000; Arrow et al . 2004). Cost–benefit analyses and other

methodologies express apples-to-oranges comparisons in

monetary currencies, making alternative options easier to

compare. In certain cases, however, service values may

Ecosystems

services

Ecological production functions translate the structure

and function of ecosystems into the provision of impor-

tant services (Heal 2000b; NRC 2005). Production func-

tions have a long tradition in agriculture and manufactur-

ing, where the amount produced of a given commodity (eg

grain) is related to the quantities and quality of the vari-

ous inputs (eg seeds, labor, chemicals, irrigation).

Estimating these functions for ecosystem services often

www.frontiersinecology.org

GC Daily et al.

Ecosystem services in decision making

(a)

(b)

(c)

(d)

(e)

(f)

Figure 4. Using InVEST to help assess management options for (a) a land-holding of Kamehameha Schools (Kawailoa, O‘ahu).

This 26 000-acre parcel has (b) prime undeveloped coastline, (c) an ancient fishpond and other important cultural assets, (d) a highly

productive agricultural belt with water resources, (e) biodiverse native upland forest, and (f) commercial and residential areas.

best be conveyed in other ways (eg the cultural impor-

tance of natural places), because assigning credible mon-

etary values is difficult or less meaningful.

In Hawai‘i, both monetary and non-monetary metrics

are important to decision makers. Kaiser and Roumasset

(2002), for example, examined the monetary contribution

of a forested watershed in enhancing groundwater

recharge, and present a clear metric for weighing the costs

and benefits of alternative approaches to watershed man-

agement. Kamehameha Schools, a major educational

trust, is developing a multi-dimensional perspective,

including economic, environmental, educational, and

community elements, with an underlying cultural founda-

tion. To evaluate land-management decisions, the trust

considers the number of student activity-days per year, the

number of areas available for gathering traditional plants

(eg for lei making), and access to sites of spiritual impor-

tance, in addition to monetary estimates of value. The

Natural Capital Project is working with Kamehameha

Schools to apply InVEST to a key tract of land on O‘ahu,

to determine the impacts of alternative land uses on bio-

physical and cultural ecosystem services (Figure 4).

More research is needed to build the credibility of

ecosystem service approaches, by: (1) combining direct

www.frontiersinecology.org

Plik z chomika:

Inne pliki z tego folderu:

Inne foldery tego chomika: