Ecological Sustainability

ECOLOGICAL SUSTAINABILITY INTRODUCTION Over the last half-century, ecologists have learned much about how ecosystems contribute to the fulfillment of human life. Most obviously, ecosystems provide many of the goods that are harvested and traded in the human economy -- food, fiber, timber, forage, biomass fuels, and many pharmaceuticals (Daily 1997a). Ecosystems also provide indirect benefits to humans through their impacts on nutrient flux and cycling, mitigation of flood and drought, and maintenance of biodiversity, all of which feedback in important ways on the production of ecosystem goods that humans directly derive from ecosystems (Chapin et al. 1996). Finally, ecosystems also provide less tangible, but equally important, benefits in the form of recreational, spiritual, and intellectual stimulation (Postel and Carpenter 1997). Despite widespread public awareness of the direct benefits that humans derive from ecosystems, the full magnitude of benefits attributable to ecosystems is woefully underappreciated by the public (Daily 1997b). The public’s failure to recognize these benefits increases the likelihood that natural resources will be managed and developed in a manner that leads to ecosystem degradation. Such resource development, in conjunction with increasing human populations and land use intensification, can stress ecosystems to a point where their ability to provide the aforementioned benefits is compromised (Rapport et al. 1985). Concern that the human enterprise may jeopardize the viability of ecosystems (Vitousek et al. 1997) is the motivation behind a natural resource management paradigm shift that is now focusing on long-term sustainability of ecosystems as the measure of responsible stewardship of natural resources (Lubchenco et al. 1991). Because the notion of ecological sustainability has a strong intuitive appeal, there are few who would criticize a natural resource management strategy that seeks to restore and maintain the composition, structure, and function of ecosystems so that future generations can derive the same ecosystem services that current generations enjoy (Johnson 1993). Despite widespread acceptance of the goals implied by ecological sustainability, there is little agreement and much contention surrounding how to implement ecological sustainability in a resource management context. Some have argued that sustainability is neither a realistic goal nor a useful concept (Ludwig et al. 1993), while others have argued that it is the only strategy leading to a viable long-term pattern of human resource use (Dale et al. 2000). There are many factors that have contributed to these varied opinions on the utility of ecological sustainability as a guide to resource management. First, and most fundamentally, is the absence of a clear definition (Pajak 2000). Certainly, ecological sustainability has been defined as a general concept that is easily understood. Sustainability has been defined as “the capacity of an area to provide the present generation with the needed direct, indirect, and spiritual benefits humans derive from ecosystems" (USDA Forest Service 2000). Applied to natural ecosystems, this definition implies that: (1) management will not degrade those systems being utilized (Lubchenco et al. 1991), and (2) the current generation of humans will leave an equitable share of resources for future generations (Meyer and Helfman 1993). However, a much more precise 2 definition is required if the concept of ecological sustainability is to move from simple statements of conviction to operational resource management. Second, the basic principles upon which to base operational definitions of sustainability have not been articulated (Chapin et al. 1996). In the absence of an agreed upon set of basic constructs, definitions to guide implementation will continue to be vague, elusive, and untested. Third, the spatial and temporal variability of ecosystems does not support a single implementation approach for ecological sustainability (Committee of Scientists 1999). Consequently, the differences among sustainable management case studies (e.g., differences in ecological attributes measured, or differences in interpretation) has been used, perhaps inappropriately, as evidence for an ill- defined management paradigm. Finally, although lists of potential indicators of ecological sustainability are beginning to emerge (Coulombe 1995, Pajak 2000, Committee to Evaluate Indicators for Monitoring Aquatic and Terrestrial Environments 2000), most lack clarity and consensus (Fluharty 2000). The primary objective of this report is to provide a clearer understanding of what ecological sustainability means and how the concept could potentially be implemented as a resource management paradigm for natural resources through the National Forest System planning process. This objective will be addressed by synthesizing information on a number of topics. First, we will review what the new planning rule specifically requires with respect to ecological sustainability. The new planning rule defines ecological sustainability as “[t]he maintenance or restoration of the composition, structure, and processes of ecosystems including the diversity of plant and animal communities and the productive capacity or ecological system” (USDA Forest Service 2000: 67580). This definition implies that there are two primary components to ecological sustainability -- ecosystem diversity and species diversity. Our review of ecological sustainability is organized around these two components Secondly, we will review the recent published literature on ecological sustainability and provide an overview of the varying perspectives of what it means to manage natural resources in an ecologically sustainable manner. This second section will attempt to distill a set of key principles of sustainable management for both ecosystem diversity and species diversity components that could help guide the agency’s forest planning process and management of natural resources. We also will examine some potential techniques and methods that could be used to assess and monitor whether the goals of ecological sustainability are being met by resource management on National Forests. Because ecological sustainability is a concept that encompasses many aspects of human development, resource management, and ecological response, it will be difficult to monitor directly. For this reason, evaluations of whether a particular ecosystem is being managed in a sustainable manner are often couched in the concept of indicators (Coulombe 1995), which ostensibly represent key measurable attributes that reflect ecosystem properties that are too difficult or costly to monitor directly (Noss 1990). An important contribution of this second section will be to propose broad classes of candidate indicators that could be used to gauge whether ecosystems occurring on National Forests are trending toward or away from conditions considered to be sustainable. Cases studies that have attempted to couch resource management under the rubric of ecological sustainability will be cited to provide examples of the methods and indicators that have been used recently to address ecological sustainability. 2 3 A final section will review key planning steps that the Agency must take to incorporate ecological sustainability in the planning process in an adaptive framework. It is important for resource planners to treat the management direction as a hypothesis that we are managing resources in a sustainable manner that is tested through monitoring. The process of developing management direction, revision of management direction and monitoring is key to placing ecological sustainability in an adaptive management framework. Although this desk guide is focusing on ecological sustainability, we fully recognize that setting goals for sustainability will necessarily be a process of integration of ecological, social, and economic components of ecosystems (Pajak 2000). A separate desk guide is being developed for social and economic sustainability and the integration of these components will be accomplished through collaborative planning efforts at local and regional scales as indicated in other parts of the planning rule. PLANNING RULE REQUIREMENTS The maintenance and restoration of ecological sustainability is the first priority for the management of national forests and grasslands so these lands can contribute to economic and social sustainability by providing a sustainable flow of uses, values, products and services (219.2). The benefits sought from these lands depend upon long-term ecological sustainability and planning will be based of the temporal and spatial scales necessary for sustainability. Ecological sustainability is defined as the maintenance or restoration of the composition, structure, and processes of ecosystems including the diversity of plant and animal communities and the productive capacity of ecological systems (219.36). Ecosystem diversity and species diversity are components of ecological sustainability [219.20 (a)]. Ecosystem Diversity Characteristics of ecosystem diversity focus on major vegetation types and success ional stages (probable occurrences under the current climate window); water resources including the diversity, abundance, distribution and dynamics of aquatic and riparian systems; soil resources as indicated by productivity; abiotic and biotic properties, and soil loss and compaction; and air resources. Another requirement is the identification of Focal Species [219.20 (1) (i) (A-E).

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