Ecological Indicators for the Nation (2000) / Chapter Skim
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1 Introduction
1 Introduction
Pages 18-26
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From page 18... ...
The bar on a thermometer indicates the temperature of a room; the light on an appliance indicates that it is turned on; the gauge on a gasoline tank indicates the amount of remaining fuel; blooms of cyanobacteria of the genus Oscillatoria in temperate-zone lakes indicate that serious pollution problems are developing. The values of an indicator over time can inform decisions about whether an intervention is desirable or necessary, which of various interventions might yield the best results, and how successful interventions have been.
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From page 19... ...
These indicators must provide information in a simpler, more comprehensible form than the complex statistics usually assembled on ecological issues, and the relationship between these indicators and the complex phenomena they represent must be evident. During recent decades, because of growing environmental concerns, increasing efforts have been devoted to developing reliable and comprehensive environmental indicators.
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From page 20... ...
and UNEP formed a Consultative Expert Group Meeting on Environment and Sustainable Development Indicators in Geneva to survey the variety of approaches being used to develop indicators. In 1994, the World Bank convened a workshop to find common ground in formulating indicators of sustainable development; and in 1995 an international policy conference was hosted by the Belgian and Costa Rican governments, together with UNEP and the Scientific Committee on Problems of the Environment (SCOPE)
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From page 21... ...
recommended that EMAP develop a focused indicator-research program, that each EMAP resource group develop a mechanistic conceptual model to underlie its indicators, that EMAP provide program-wide guidance for indicator development to ensure at least a consistent philosophy behind the indicators developed for the various resource groups, and that EMAP evaluate each indicator at incrementally larger spatial scales. Recognizing the difficulty of implementing these recommendations, then Assistant Administrator of the EPA's Office of Research and Development Robert Huggett requested the NRC's help.
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From page 22... ...
People value ecological goods and services for a variety of reasons. In this report, ecological goods and services refer not only to food, fiber, building materials, and medicines, but also to the roles of ecosystem processes in protecting watersheds, reducing the frequency and severity of floods, purifying waters, and shaping local, regional, and global climates.
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From page 23... ...
An example is the extinction of species, which is clearly irreversible. Although history demonstrates that the diversity of life recovers following mass extinctions, recovery may take from one to 10 million years and lost species are not necessarily replaced by anything similar.
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From page 24... ...
In addition, environmental processes such as glaciation, other climatic changes, and geological forces alter the distributions and abundances of species and biological communities. Some of these changes are so slow that they are unlikely to affect the choice of reference states or reading of indicators over periods of several hundred years, but some can occur at rates roughly similar to changes caused by human population growth
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From page 25... ...
Using shifting baselines for environmental conditions may well also lead to a relaxation of standards: gradual environmental deterioration can pass unnoticed under such a regime, in what has been called the "shifting baseline syndrome" (Pauly 1995~. For example, Trautman (1981)
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From page 26... ...
For each indicator, it is of course essential to periodically evaluate its usefulness, reliability, and cost-effectiveness. REALISTIC EXPECTATIONS ABOUT THE VALUE OF INDICATORS The value of ecological indicators rests on the premise that better understanding of what is happening in the nation's ecosystems leads to better and more effective policies for encouraging desirable changes, discouraging undesirable changes, and maintaining variability within "tolerable" limits.
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