Valuing Ecosystem Services Toward Better Environmental Decision-Making (2005) / Chapter Skim
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3 Aquatic and Related Terrestrial Ecosystems
3 Aquatic and Related Terrestrial Ecosystems
Pages 59-94
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From page 59... ...
Most ecologists and environmental regulators also include vegetated wetlands as members of the set of aquatic ecosystems, and many think of groundwater aquifer systems as potential members of the set. "Aquatic and related terrestrial ecosystems" is a phrase that recognizes the impossibility of analyzing aquatic systems absent consideration of the linkages to adjacent terrestrial environments.
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From page 60... ...
and the physical and biological organization defining how those parts are organized. A leopard frog or a marsh plant such as a cattail, for example, would be considered a component of an aquatic ecosystem and hence part of its structure.
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From page 61... ...
Despite these shortcomings, the core issue of how to assess and value aquatic ecosystem services is intuitive and important enough to support some synthesis -- especially as related to environmental decision-making. The goal of this chapter is to review and summarize some of the common elements in the published literature concerning the identification of aquatic ecosystem functions and their linkage to goods and services for subsequent economic valuation.
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From page 62... ...
These reports are required by Section 305(b) of the Clean Water Act and are considered by EPA to be the primary vehicle for informing Congress and the public about general water quality conditions in the United States.
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From page 63... ...
Water quality gradually improved so that the "oligotrophic blue" is reestablished in all the lakes. Between 1974 and 1994, PCB levels in top-of-the-food-web predators dropped by as much as 90 percent.
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From page 64... ...
Invasive and exotic species such as zebra mussels, lamprey, ruffe, and goby, however, continue to displace and threaten native species. The Great Lakes region can be viewed a continuing experiment in testing human capability to live and prosper within the bounds of a major aquatic ecosystem, and although the last four decades allow some optimism, major environmental problems remain.
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From page 65... ...
Louis to Fort Benton, Montana. Social values and goals in the Missouri River basin during this period reflected national trends and the preferences of basin inhabitants.
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From page 66... ...
However, new ecological programs, both newly created and proposed, should permit a comprehensive and consistent assessment of all of the nation's coastal resources by 2005. The NCCR used aggregate scores for a total of seven water quality indicators (water clarity, dissolved oxygen, coastal wetland loss, contaminated sediments, benthos, fish tissue contaminants, and eutrophic condition)
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From page 67... ...
The challenge of restoring the system's productivity has motivated investment of millions of dollars of public funds through the Chesapeake Bay Program, a cooperative effort by states and the federal government to reduce impacts and improve conditions in the ecosystem. The extensive and complex array of stakeholder groups, commitments, and programs orchestrated under the umbrella of this program has become a model for similar efforts emerging in other large aquatic ecosystems.
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From page 68... ...
in the area began to dry up following a seven-year drought in the 1950s. Groundwater storage is critical in most aquatic ecosystems to provide persistent springs and streams during drought.
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From page 69... ...
. Their main ecosystem functions are breaking down organic matter and turning dead materials (detritus)
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From page 70... ...
and increased human population growth will stress the current rules on allocation of water to maintain natural ecosystem functions and survival of endangered species.
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From page 71... ...
Methods for valuing ecosystem services would help provide an answer.
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From page 72... ...
72 Valuing Ecosystem Services continues Inventory e ourc Res Quality tera Wl tionaaN 2002 the from ltsu Res nda ngs ndiiF ctede Sel 1 3 ableT
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From page 73... ...
Aquatic and Related Terrestrial Ecosystems 73 ed inu Cont 1 3 ableT
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From page 74... ...
Between 1986 and 1997, the net loss of wetlands was 644,000 acres with an annual loss rate of 58,545 acres (see also Table 1-1) ; 98 percent of these losses occurred in freshwater wetlands.4 A fourth major federal program report related to the extent and status of aquatic and related terrestrial ecosystems is the Summary Report of the 1997 National Resources Inventory (Revised December 2000)
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From page 75... ...
There are at least three key elements in the effective description of aquatic ecosystems: (1) geomorphology, (2)
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From page 76... ...
The fact that there is no explicit and invariant link between structure and function of aquatic ecosystems is part of the problem in efforts to assess all goods and services provided by these natural systems. If the behavior of a particular ecosystem is dependent not only on its composition, but also on linkages to surrounding systems and the impact of stressors, then comprehensive recognition of goods and services provided is not straightforward.
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From page 77... ...
Thus, as a generality, mapping ecosystem goods and services does not proceed linearly from system structure. The default response to the lack of a simple logic linking structure to function has been development of generalized lists of potential functions appropriate to broad categories of aquatic ecosystems.
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From page 78... ...
Although a perfect taxonomy for ecosystem functions remains elusive, this may be less important than developing a consensus on an appropriate cumulative list of potential aquatic ecosystem functions. In this regard, de Groot et al.
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From page 79... ...
. ." Many of the goods and services provided by aquatic ecosystems are intuitive, such as potable water sources, food production, transportation, waste removal, and contributing to landscape aesthetics.
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From page 80... ...
Pollution dilution and water quality protection Hydroelectric generation Bird and wildlife habitat Soil fertilization Enhanced property values Nonuser values Wetland Ecosystem Services (Ewel, 2002) Biodiversity: Sustenance of Plant and Animal Life Evolution of unique species Production of harvested wildlife: Water birds, especially waterfowl Fur-bearing mammals (e.g., muskrats)
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From page 81... ...
. TABLE 3-3 Functions, Goods, and Services of Natural and Seminatural Ecosystems Ecosystem Processes and Functions Components Goods and Services Regulation Maintenance of essential ecological processes and life support systems Gas regulation Role of ecosystems in Ultraviolet-B protection biogeochemical cycles Maintenance of air quality Influence on climate Climate regulation Influence of land cover and Maintenance of tempera biologically mediated ture, precipitation processes Disturbance prevention Influence of system struc- Storm protection ture on dampening Flood dampening environmental disturbance Water regulation Role of land cover in regu- Drainage and natural lating runoff and river irrigation discharge Medium for transport Water supply Filtering, retention, and Provision of water for storage of freshwater consumptive use (e.g., in aquifers)
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From page 82... ...
Aquaculture Production Provision of natural resources Food Conversion of solar energy Building and manufacturing into edible plants and Fuel and energy animals Fodder and fertilizer Raw materials Conversion of solar energy Improve crop resistance to into biomass for human pathogens and pests construction and other uses Genetic resources Genetic material and evolu- Drugs and pharmaceuticals tion in wild plants and Chemical models and tools animals Test and assay organisms Medicinal resources Variety of (bio) chemical substances in, and other medicinal uses of, natural biota Ornamental resources Variety of biota in natural Resources for fashion, ecosystems with (poten- handicraft, worship, tial)
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From page 83... ...
Recognition of the thresholds of change in both space and time is one of the principal challenges in ecological research. Scale It may be argued that almost all ecosystem functions can be performed by aquatic ecosystems at any scale.
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From page 84... ...
The implication is that aggregation of service values to larger scales or composite system evaluations will almost axiomatically misrepresent the processes at the TABLE 3-4 Examples of the Generation of Ecosystem Services at Different Scales for Aquatic Ecosystems Time or Space Scale Example of Scale at Which (day) (meters)
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From page 85... ...
Indeed, examples of thresholds and regime shifts in aquatic ecosystems have been a significant part of the evolving understanding of nonlinear ecosystem behavior (Muradian, 2001; Scheffer and Carpenter, 2003; Scheffer et al., 2001; Walker and Meyers, 2004)
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From page 86... ...
production overwhelm secondary production and decomposition processes, resulting in excessive accumulation of organic matter, depletion of oxygen in the water column, and a change in the trophic structure. The change can represent a new and undesirable condition that may persist even if nutrient loads are reduced (see Carpenter, 2003; Carpenter et al., 1998)
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From page 87... ...
of the ecosystem itself." Incomplete Knowledge Comprehensive valuation of aquatic ecosystems should be viewed as a practical improbability. The assumption that our knowledge is imperfect is at
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From page 88... ...
· As the committee pursued its charge, the problems of developing an interdisciplinary terminology and/or a universally applicable protocol for valuing aquatic ecosystems were illuminated, but ultimately identified as unnecessary objectives. · From an ecological perspective, the value of specific ecosystem functions/services is entirely relative.
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From page 89... ...
· Further integration of the sciences of economics and ecology at both intellectual and practical scales will improve ecologists' ability to provide useful information for assessing and valuing aquatic ecosystems. There remains a significant amount of research and work to be done in the ongoing effort to codify the linkage between ecosystem structure and function and the provision of goods and services for subsequent valuation.
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From page 90... ...
1993. Karst aquatic ecosystems of the Edwards Plateau region of central Texas, USA -- A consideration of their impor tance, threats to their existence, and efforts for their conservation.
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From page 91... ...
2002. Economic and ecological concepts for valuing ecosystem services.
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From page 92... ...
1999. Limiting pumping from the Edwards Aquifer: An economic investigation of proposals, water markets, and spring flow guarantees.
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From page 93... ...
1999. The Edwards Aquifer water re source conflict: USDA farm program resource-use incentives?
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From page 94... ...
In Sustainability of Wetlands and Water Resources: Achieving Sustainable Systems in the 21dst Century, M.M. Holland, E
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