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The Santa Cruz Mountains is a coastal landscape with a history of extensive forest logging, and a future with projected climate warming that may alter vegetation cover and surface water runoff in new ways. Results from Landsat satellite image time-series analysis since 1983 of this study area showed gradual, statistically significant increases in the normalized difference vegetation index (NDVI) in more than 90 % of the (predominantly second-growth) evergreen forest locations sampled. The cumulative distribution of NDVI values in 2013 was significantly different and higher overall from the cumulative distribution of NDVI values in 1983. The extreme drought year of 2013 (and other previous years of low precipitation) did not affect average NDVI growth rates in most drainage basins of the study area, with the exception of four relatively small basins that had less than 30 % forested land cover. Notably different patterns of NDVI change were detected in areas burned by wildfires in recent years. Within the perimeters of the 2008 Summit Fire and the 2009 Lockheed Fire, NDVI showed notable declines from pre-fire levels to those calculated in 2013 Landsat imagery. In contrast to these recent fires, the burned area from the 1985 Lexington Fire showed the highest rate of NDVI increase (over 27 years of regrowth) of any relatively large contiguous area within the Santa Cruz Mountains.  相似文献   
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The integrity of the relationship between humanity and nature is fundamental to the health and survival of our species. Humans have always required knowledge and understanding of the planet’s life-supporting systems. Such knowledge and understanding form the basis of ecological literacy which, we suggest, is fundamental to the sustainability of human settlements. An assessment of South Australian adults showed positive correlations between ecological literacy and a number of socio-demographic and psychographic factors. An analysis of the most and least eco-literate individuals within a sample of over 1000 adults revealed significant distinguishing characteristics. Our findings indicate that high ecological literacy is strongly correlated with gender, age, education (and in particular, science-based education), employment status, engagement with nature both as children and adults, growing food, outdoor experiences and lifestyles, growing up in small communities and relational learning. In contrast, low ecological literacy is associated with a different set of socio-demographic and psychographic characteristics such as lower levels of education, growing up in large urban communities, and spending little time outdoors or in natural settings. In addition, perceptions about the major contributors to ecological knowledge and understanding were markedly different within the two groups. These patterns of difference between those with high and low ecological literacy among South Australian adults invite serious consideration for a society that aspires to cultivate an informed citizenry with capacity for making effective environmental decisions.  相似文献   
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Behavioral Ecology and Sociobiology - Behavioural diversity is a basic component of biodiversity, with implications in ecological interactions at the intra- and interspecific levels. The...  相似文献   
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南极生态系统特定的环境质量指导值和修复目标是进行南极污染场地风险评估和修复的必需条件。南极土壤生物的生态毒理学测试是确定可靠的污染物效应阈值浓度的基础。本研究描述了针对生活在土壤颗粒间隙水中的南极特有的土壤线虫Plectus murrayi的最佳培养技术和水生毒性实验程序。毒性试验持续时间较长,用于揭示该物种的生理学和生活史特征。Plectus murrayi对水溶性铜的敏感性表现其卵孵化率的效应浓度(EC50)为139 μg/L。首次以卵的形式接触水溶性铜的孵化幼体不如在孵化的J2期初次接触铜的幼体敏感,这表明该卵具有潜在的保护作用。幼体对铜的敏感性随着暴露时间的延长而增加, 21天和28天的半数致死浓度(LC50s)分别为478 μg/L和117 μg/L。本研究描述了应用于南极土壤污染物对环境相关测试物种的风险评估新方法,并首次估算了南极陆生微型无脊椎动物对毒物的敏感性。  相似文献   
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ABSTRACT: The role of environmental mitigation in permitting decisions under Section 404 of the Clean Water Act and the National Environmental Policy Act is examined, addressing the extent to which compensatory mitigation is acceptable. The role of mitigation is examined both generically and specifically: first in the requirements of the Clean Water Act and NEPA, and then in the case study of the proposed Two Forks Dam. In both cases, the paper describes dual purposes of environmental protection legislation and mitigation: to protect the biophysical environment and maintain associated human values. Mitigation is found to be sometimes necessary and acceptable as compensation for unavoidable impacts of project development. However, the Two Forks case exemplifies that compensatory mitigation has also been employed as a mechanism to facilitate project development when practicable alternatives entailing less environmental impact are available. Acceptance of compensatory mitigation in such cases violates both the Guidelines of the Clean Water Act and the intent of that Act and NEPA to protect the biophysical environment and human welfare. A recent memorandum of agreement between the Corps and the EPA clarifies this policy, and suggests that permit applications which rely on compensatory mitigation when impacts are available may be denied.  相似文献   
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