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Ecosystem Integrity/Health Report Card

Drs. Harwell and Gentile led the development of an ecosystem integrity or health report card (Harwell et al. 1999), which was designed to meet the following criteria: 1) be understandable to multiple audiences, including scientists, decision-makers, stakeholders, and the general public, translating scientific information into policy-relevant terms; 2) address ecological responses across time scales, up to the long time scales for evaluating ecological sustainability; 3) show status and trends in terms of selected ecosystem endpoints, reported in the context of natural variability to characterize a real signal vs. environmental noise; 4) indicate progress made towards specified ecological goals, including how much has been accomplished or remains to be achieved; 5) characterize selected ecosystem endpoints that are ecologically or societally significant; 6) provide the scientific bases for assigned grades, including monitoring data, models, and experiments behind the assessment; and 7) be explicitly coupled to ecological conceptual describing causal relationships among societal drivers, environmental stressors, and ecological effects. The hierarchical structure that we developed for an ecosystem health report card (Harwell et al. 1996, Harwell 1997, 1998) is illustrated in Figure 1.

Figure 1

 

Tiers 1 and 2 Goals, Objectives — The highest tier in the framework is the environmental goals, the very broad-level articulation of societal values and desired ecosystem conditions of each part of a regional environment. The second tier, termed objectives, is a disaggregation of the goals into more specific items, characterized in layperson’s terms. This concept derives from the principles of ecosystem management (US MAB 1994; Harwell et al. 1996; IEMTF 1995; Christensen et al. 1996) in which societal decisions are made about the desired sustainability condition of each part of the landscape. Such decisions are both informed and constrained by science, but are made through various mechanisms to convert societal preferences and values into environmental decisions (NRC 1996). An important characteristic of the ecosystem sites selected for this study is the existence of well-defined goals and objectives.

Tier 3 Essential Ecosystem Characteristics (EECs) —The middle tier in the report card framework, essential ecosystem characteristics (EECs), provides the critical interface between societal ecosystem goals and objectives and scientifically determined characteristics of the ecological systems. EECs constitute a description of ecosystem characteristics that define the essence of the particular ecosystem at a specified level of integrity. By translating goals and objectives into EECs, scientists provide clarity and specificity to what society wants, explaining to nonscientists what the scientific terms mean. EECs capture relevant scientific information into a number of discrete, but not necessary independent characteristics, describing major ecological features in any ecosystem.

Tiers 4 and 5 Ecosystem Endpoints (VECs), Measures, Indicators —The next lower tier in the framework, ecosystem endpoints, are those ecosystem-specific attributes that describe the ecosystem at the level of detail necessary to characterize ecosystem integrity, also known as Valued Ecosystem Components (VECs). Thus, ecosystem endpoints are defined in the report card framework identical to the ecological risk assessment framework (Harwell and Gentile 1992; Gentile et al. 1993; US EPA 1992, 1998), and map directly onto the ecological conceptual model construct. Finally, the lowest tier of the report card framework, ecosystem measures or indicators, constitutes the specific attributes that need to be measured or monitored in the environment to reflect on the status or trends of the VECs and associated EECs. In essence, this tier defines the field measurements that provide the foundations for the report card. The rules for selecting VECs (Harwell et al. 1990) include identifying ecological attributes that are important ecologically or societally, and covering different levels of biological organization (population, community, ecosystem, and landscape levels) to identify the ecosystem-specific attributes that, if changed, would constitute a change in the integrity of the ecosystem. An attribute’s importance may reflect its ecological role (e.g., ecological processes, keystone species) or its value to society (e.g., endangered species). Other societally important ecosystem endpoints include economically important species (e.g., commercial or recreational fishes), aesthetic species (e.g., wading birds), or landscape-level aesthetics (e.g., natural vistas). Consequently, the tier of ecosystem endpoints overlaps between scientific and societal issues, and is central to the issue of ecological significance (Gentile and Harwell 1998). Following the ecological risk assessment framework (Gentile et al. 1993), both stressors and ecological effects need to be monitored and evaluated in parallel to understand anthropogenic risks to the environment; consequently, both stressor and effects endpoints and measures need to be incorporated into the report card. Each stressor endpoint should have stressor measures to characterize stressor intensity, frequency, duration, and distribution.

By explicitly coupling the indicators to the goals and objectives for an area, the resulting ecological health indicators will be directly relevant to decision managers and more likely to be utilized in support of environmental decision making. By capturing the ecological understanding and uncertainties in the conceptual model, stressor-effects linkages are made explicit, assumptions made transparent, and monitoring activities made relevant.

 

References Cited:

Christensen, N.C., et al. 1996. The report of the Ecological Society of America Committee on the Scientific Basis for Ecosystem Management. Ecological Applications6:665-691. 

Gentile, J.H., M.A. Harwell, W. van der Schalie, S. Norton, and D. Rodier. 1993. Ecological risk assessment: a scientific perspective. J. Hazardous Materials 35: 241-253.

Harwell, Mark A. and Jack Gentile.  1992.  Report of the EPA Ecological Risk Assessment Guidelines Strategic Planning Workshop, Miami, FL, May 1991.  US Environmental Protection Agency, Risk Assessment Forum, Washington, DC.

Harwell, Mark A., John F. Long, Ann M. Bartuska, John H. Gentile, Christine C. Harwell, Victoria Myers, and John C. Ogden. 1996. Ecosystem management to achieve ecological sustainability: the case of South Florida. Environmental Management  20(4):497-521.

Harwell, Mark A.  1997.  Ecosystem management of South Florida.  BioScience  47(8): 499-512.

Harwell, Mark A. 1998. Science and environmental decision-making in South Florida. Ecological Applications 8(3): 580-590.

Harwell, Mark A., Victoria Myers, Terry Young, Ann Bartuska, Nancy Gassman, John H. Gentile, Christine C. Harwell, Stuart Appelbaum, John Barko, Billy Causey, Christine Johnson, Agnes McLean, Ron Smola, Paul Templet, Stephen Tosini. 1999. A framework for an ecosystem integrity report card.  BioScience 49(7):543-556.

IEMTF [Interagency Ecosystem Management Task Force]. 1995. The ecosystem approach:  healthy ecosystems and sustainable economies. Three volumes. National Technical Information Center, U.S. Department of Commerce, Springfield, Virginia, USA. 

NRC. 1996. Understanding Risk:  Informing Decisions in a Democratic Society.  P.C. Stern and H.V. Fineberg, editors.  National Academy Press, Washington, D.C., USA. 

US EPA (US Environmental Protection Agency). 1992. Framework for ecological risk assessment. Washington (DC), USA: US Environmental Protection Agency Risk Assessment Forum. EPA/630/R-92/001.

US EPA (US Environmental Protection Agency). 1998. Guidelines for ecological risk assessment. Washington (DC), USA: US Environmental Protection Agency. EPA/630/R-95/002F.

 

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