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51.
ROBERT L. BESCHTA††† JONATHAN J. RHODES† J. BOONE KAUFFMAN‡ ROBERT E. GRESSWELL§ G. WAYNE MINSHALL JAMES R. KARR†† DAVID A. PERRY‡‡ ‡‡‡ F. RICHARD HAUER§§ CHRISTOPHER A. FRISSELL 《Conservation biology》2004,18(4):957-967
Abstract: Forest ecosystems in the western United States evolved over many millennia in response to disturbances such as wildfires. Land use and management practices have altered these ecosystems, however, including fire regimes in some areas. Forest ecosystems are especially vulnerable to postfire management practices because such practices may influence forest dynamics and aquatic systems for decades to centuries. Thus, there is an increasing need to evaluate the effect of postfire treatments from the perspective of ecosystem recovery. We examined, via the published literature and our collective experience, the ecological effects of some common postfire treatments. Based on this examination, promising postfire restoration measures include retention of large trees, rehabilitation of firelines and roads, and, in some cases, planting of native species. The following practices are generally inconsistent with efforts to restore ecosystem functions after fire: seeding exotic species, livestock grazing, placement of physical structures in and near stream channels, ground-based postfire logging, removal of large trees, and road construction. Practices that adversely affect soil integrity, persistence or recovery of native species, riparian functions, or water quality generally impede ecological recovery after fire. Although research provides a basis for evaluating the efficacy of postfire treatments, there is a continuing need to increase our understanding of the effects of such treatments within the context of societal and ecological goals for forested public lands of the western United States. 相似文献
52.
BENJAMIN S. HALPERN†§§ CHRISTOPHER R. PYKE HELEN E. FOX‡§ J. CHRIS HANEY MARTIN A. SCHLAEPFER†† PATRICIA ZARADIC‡‡ 《Conservation biology》2006,20(1):56-64
Abstract: Several international conservation organizations have recently produced global priority maps to guide conservation activities and spending in their own and other conservation organizations. Surprisingly, it is not possible to directly evaluate the relationship between priorities and spending within a given organization because none of the organizations with global priority models tracks how they spend their money relative to their priorities. We were able, however, to evaluate the spending patterns of five other large biodiversity conservation organizations without their own published global priority models and investigate the potential influence of priority models on this spending. On average, countries with priority areas received greater conservation investment; global prioritization systems, however, explained between only 2 and 32% of the US$1.5 billion spent in 2002, depending on whether the United States was removed from analyses and whether conservation spending was adjusted by the per capita gross domestic product within each country. We also found little overlap in the spending patterns of the five conservation organizations evaluated, suggesting that informal coordination or segregation of effort may be occurring. Our results also highlight a number of potential gaps and mismatches in how limited conservation funds are spent and provide the first audit of global conservation spending patterns. More explicit presentation of conservation priorities by organizations currently without priority models and better tracking of spending by those with published priorities are clearly needed to help make future conservation activities as efficient as possible. 相似文献
53.
Current Practices and Future Opportunities for Policy on Climate Change and Invasive Species 总被引:2,自引:0,他引:2
CHRISTOPHER R. PYKE ROXANNE THOMAS† READ D. PORTER† JESSICA J. HELLMANN‡ JEFFREY S. DUKES§ DAVID M. LODGE‡ GABRIELA CHAVARRIA 《Conservation biology》2008,22(3):585-592
Abstract: Climate change and invasive species are often treated as important, but independent, issues. Nevertheless, they have strong connections: changes in climate and societal responses to climate change may exacerbate the impacts of invasive species, whereas invasive species may affect the magnitude, rate, and impact of climate change. We argue that the design and implementation of climate-change policy in the United States should specifically consider the implications for invasive species; conversely, invasive-species policy should address consequences for climate change. The development of such policies should be based on (1) characterization of interactions between invasive species and climate change, (2) identification of areas where climate-change policies could negatively affect invasive-species management, and (3) identification of areas where policies could benefit from synergies between climate change and invasive-species management. 相似文献