Abstract
The Environmental Impact Statement (EIS) attempts to portray the current character of a given ecosystem. This provides a “Baseline” against which future possible changes can be assessed. Ecosystems, however, are dynamic and in a constant state of change. Consequently, data representing a single year reflect conditions only for that year and can be misleading if compared against any other year. In addition to this temporal variation, considerable spacial variation exists in species composition and cover. Ample sampling is required to compensate for this heterogeneity. Variation, or background “noise,” can be minimized by the use of similarity indexes and sampling over a period of at least two years.
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Treshow, M., Allan, J. Uncertainties associated with the assessment of vegetation. Environmental Management 9, 471–477 (1985). https://doi.org/10.1007/BF01867321
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DOI: https://doi.org/10.1007/BF01867321