Risk of Impaired Condition of Watersheds Containing National Forest Lands

ISBN-13: 9781480163492 / Angielski / Miękka / 2012 / 64 str.

Thomas C. Brown; Pamela Froemke; U. S. Department of Agriculture

Opis

This report was produced with two objectives in mind. First, we sought to provide a nationwide assessment based on relatively good quality, consistent data, which could serve as a point of reference for pending decisions about agency watershed condition assessment. Second, we hoped to offer information that would be useful in making broad-scale decisions about where more in-depth assessment would be most helpful. Our end products-this report and its associated spreadsheets of data and metrics of risk to watershed condition-offer a great deal of information about nearly 3700 5th-level watersheds across the lower 48 states. Two qualifications about this information are most important. First, this is a nationwide analysis, which most appropriately supports broad-scale comparisons and decisions. Because good quality nationwide data sets are not available for some variables that may be of interest in specific locations, and because even good quality nationwide data sets sometimes fail to accurately characterize local situations, the results will probably provide only a starting point for watershed assessments at local scales, such as that of a national forest. Also, although we performed the analysis using what for a nationwide assessment is considered a very fine spatial scale, that scale may not be sufficiently fine for local planning needs. Second, because consistent nationwide data on soil quality, on aquatic species populations, and on water quantity, quality, and timing were not available, this assessment examines the risk of impaired watershed condition, not the actual condition of watersheds.