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61.
Compared to burn interiors, edges exhibit distinct biotic and abiotic conditions that include microclimate, wind speed, sunlight levels, soil composition, moisture content, nutrient availability, population density, and species diversity. This study characterized the landscapes in which burned forest edges formed in Samcheok, Korea. Over the study area, 500-m2 grid cells were generated to capture landscape characteristics. Grid cells intersecting burn boundary lines were designated as edge, while cells without these lines were classified as the interior of burned areas. Topographic variables including slope, elevation, topographic wetness index, solar radiation index, and proportions of fuel and land use types within grid cells were computed in a geographical information system (GIS). Correlation analysis with modified t-test and regression tree analysis were performed to explore the influences of landscape variables on edge formation with avoiding spatial autocorrelation problems. The results indicated that edges formed at low elevations with mild slopes, high topographic wetness, and low solar radiation. Edges were unlikely to form in areas dominated by Japanese red pines at low elevations. Moreover, heterogeneous land use/cover types contributed significantly to edge formation. Different forest management strategies for different landscape conditions can be more effective for enhancing resilience of forests to fire. Reducing susceptible fuel types might be effective at low elevations, while enhancing forest heterogeneity might be more effective at high elevations. 相似文献
62.
火烧寨锑金(砷)矿位于黔东南雷公山多金属成矿带的双尧—火烧寨成矿亚带。通过对成矿地质特征和矿床地球化学特征的研究,提出矿带主要受控于深切地幔的独山—松桃深大断裂及分支断裂,成矿活动与构造-岩浆活动具有同步性,并总结了成矿富集规律。 相似文献