[20010221]RS20822_森林生态系统健康：概述.pdf

Congressional Research Service ? The Library of CongressCRS Report for CongressReceived through the CRS WebOrder Code RS20822February 21, 2001Forest Ecosystem Health: An OverviewRoss W. GorteNatural Resource Economist and Senior Policy AnalystResources, Science, and Industry DivisionSummaryAlthough most U.S. forests are in better condition than they were a century ago,many forest ecosystems, especially in the intermountain west, are widely thought to bein poor health. Interest groups disagree over what constitutes a healthy forest, what hascaused the problems, and what the solutions are. Nonetheless, most accept that highbiomass accumulations dead and dying trees, dense undergrowth, and stands of smalltrees can contribute to catastrophic wildfires, pest problems, and lower biologicaldiversity. A variety of tools and approaches have been proposed and debated to addressthe problems, including salvage and other timber sales, prescribed burning, and othertreatments. Legislative and administrative efforts have generally focused on the nationalforests, to create new forest health programs and management tools or to authorizealternative treatment approaches. This report will be updated as