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701.
Abstract: We used socioeconomic models that included economic inequality to predict biodiversity loss, measured as the proportion of threatened plant and vertebrate species, across 50 countries. Our main goal was to evaluate whether economic inequality, measured as the Gini index of income distribution, improved the explanatory power of our statistical models. We compared four models that included the following: only population density, economic footprint (i.e., the size of the economy relative to the country area), economic footprint and income inequality (Gini index), and an index of environmental governance. We also tested the environmental Kuznets curve hypothesis, but it was not supported by the data. Statistical comparisons of the models revealed that the model including both economic footprint and inequality was the best predictor of threatened species. It significantly outperformed population density alone and the environmental governance model according to the Akaike information criterion. Inequality was a significant predictor of biodiversity loss and significantly improved the fit of our models. These results confirm that socioeconomic inequality is an important factor to consider when predicting rates of anthropogenic biodiversity loss. 相似文献
702.
KARINE PAYET MATHIEU ROUGET KAREN J. ESLER BELINDA Reyers TONY REBELO MARK W. THOMPSON JAN H. J. VLOK 《Conservation biology》2013,27(3):531-541
Extinction‐risk assessments aim to identify biological diversity features threatened with extinction. Although largely developed at the species level, these assessments have recently been applied at the ecosystem level. In South Africa, national legislation provides for the listing and protection of threatened ecosystems. We assessed how land‐cover mapping and the detail of ecosystem classification affected the results of risk assessments that were based on extent of habitat loss. We tested 3 ecosystem classifications and 4 land‐cover data sets of the Little Karoo region, South Africa. Degraded land (in particular, overgrazed areas) was successfully mapped in just one of the land‐cover data sets. From <3% to 25% of the Little Karoo was classified as threatened, depending on the land‐cover data set and ecosystem classification applied. The full suite of threatened ecosystems on a fine‐scale map was never completely represented within the spatial boundaries of a coarse‐scale map of threatened ecosystems. Our assessments highlight the importance of land‐degradation mapping for the listing of threatened ecosystems. On the basis of our results, we recommend that when budgets are constrained priority be given to generating more‐detailed land‐cover data sets rather than more‐detailed ecosystem classifications for the assessment of threatened ecosystems. El Efecto de la Cobertura Terrestre y el Mapeo de Ecosistemas en la Valoración de Riesgos en los Ecosistemas en Little Karoo, Sudáfrica 相似文献
703.
When populations decline in response to unfavorable environmental change, the dynamics of their population growth shift. In populations that normally exhibit high levels of variation in recruitment and abundance, as do many amphibians, declines may be difficult to identify from natural fluctuations in abundance. However, the onset of declines may be evident from changes in population growth rate in sufficiently long time series of population data. With data from 23 years of study of a population of Fowler's toad (Anaxyrus [ = Bufo] fowleri) at Long Point, Ontario (1989–2011), we sought to identify such a shift in dynamics. We tested for trends in abundance to detect a change point in population dynamics and then tested among competing population models to identify associated intrinsic and extrinsic factors. The most informative models of population growth included terms for toad abundance and the extent of an invasive marsh plant, the common reed (Phragmites australis), throughout the toads’ marshland breeding areas. Our results showed density‐dependent growth in the toad population from 1989 through 2002. After 2002, however, we found progressive population decline in the toads associated with the spread of common reeds and consequent loss of toad breeding habitat. This resulted in reduced recruitment and population growth despite the lack of significant loss of adult habitat. Our results underscore the value of using long‐term time series to identify shifts in population dynamics coincident with the advent of population decline. Efectos de una Planta Invasora sobre las Dinámica Poblacional de Sapos 相似文献
704.
Effects of habitat and landscape fragmentation on humans and biodiversity in densely populated landscapes 总被引:3,自引:0,他引:3
Manuela Di Giulio Rolf Holderegger Silvia Tobias 《Journal of environmental management》2009,90(10):2959-2968
Landscape fragmentation has often been seen as an only ecological problem. However, fragmentation also has a societal perspective, namely, in how humans perceive landscape fragmentation and in how landscape fragmentation potentially influences human well-being. These latter aspects have rarely been addressed so far. The inter-relationship of ecological and human dimensions of landscape fragmentation becomes especially evident when looking at the landscape where most people in industrial countries live, namely in suburban and urban areas. In these areas, landscape planners and environmental managers are confronted with the problem that landscapes should fullfil various functions, often with conflicting goals, e.g. nature reserves to enhance species richness vs. recreational areas for city-dwellers. We reviewed the ecological and sociological literature relevant for fragmentation in suburban and urban landscapes. In an interdisciplinary approach, we evaluated whether there are similarities and dissimilarities between the ecological and the human aspects of landscape fragmentation. We found important similarities. An example is that for both, humans and biodiversity, the loss of semi-natural areas has more drastic effects than the fragmentation of these areas per se. However, there are also relevant differences. We concluded that in densely populated landscapes a shift from responsive planning to an intentional design of environments is therefore needed. 相似文献
705.
水土流失区采用综合防治措施取得了水土保持的良好综合效益,在市场经济条件下,在综合效益中,社会效益和生态效益比较,人们更重视经济效益。兴办经济实体,对水土流失区进行开发型治理,已成为人们的普遍要求。开发型治理模式是传统综合模式的提高,它要求有足够的基础投入;要有高素质的管理人才和技术,要选准开发对象,变水土保持重声势重规模为重管理重效益,因而其三大效益将有显著提高。宁都县漆树开发引种初露成效。 相似文献
706.
长江流域水土流失及其防治 总被引:4,自引:0,他引:4
史德明 《长江流域资源与环境》1992,1(1):10-70
对长江流域水土流失现状和分布作了具体分析,指出建国以来水土流失有发展趋势;从土壤资源、土地资源、水资源与生态环境等方面,阐述了水土流失对资源环境的破坏性;着重指出了长江流域的流失物质、泥沙输移比和沉积规律与我国黄土高原流失区有着不同的特点,同时存在着比黄土高原更大的潜在危险;针对长江流域水土流失特点、发生原因并结合兴建三峡工程和长江经济带的开发,从战略高度提出了防治水土流失的策略和措施。 相似文献
707.
基于2008~2016年湘江流域内40个监测站点10项参数的月观测资料,运用水质指数法分析流域水质时空分异特征,并采用主成分分析和多元线性回归分析识别影响流域水环境演变的主要因素.在此基础上将水质、水量与水资源价值结合起来,利用改进的污染损失率法和模糊数学法,构建污染价值损失模型,定量估算流域水污染经济损失.结果表明,湘江流域水质总体以优为主,2008~2011年水质变差,2011年后水质逐渐改善,2015~2016年改善状况较为明显.在季节尺度上,枯水期水质最差,丰水期和平水期接近.流域主要污染物是Hg、Pb、TP、NH4+-N和CODMn.经济发展是影响流域水质变化的主要驱动因素.污染价值损失结果表明,长沙和郴州损失量最大,湘潭、株洲和衡阳次之,娄底损失最小.在年际尺度上,2013年污染损失最高(297.04亿元),2008年最低(66.53亿元),总体上2008~2016年污染损失在波动中增加. 相似文献
708.
基于多区域投入产出模型,测算了2019年京津冀地区13个城市重污染天气应急响应对本地区造成的直接经济损失、通过产业链传导造成的间接经济损失和区域间溢出效应.研究发现,应急响应对地区经济的影响具有明显的间接性和溢出性.河北省承担的经济损失高于天津和北京,其中石家庄市面临的经济损失规模最高(97.51亿元),邢台市面临的经济损失占地区经济总产值的比重最高(2.60%).天津和北京承担的经济损失分别为56.89,56.61亿元,占地区经济总产值比重分别为0.40%和0.16%.重污染天气应急响应对于高能耗、高污染部门造成的冲击较大,例如,化学工业、石油加工、炼焦及核燃料加工业等.研究结果对于京津冀大气污染联防联控有一定的借鉴意义,现行的空气质量奖惩问责制度的“以偿代补”效果并不理想,建议尽早建立京津冀跨区域空气质量横向补偿机制. 相似文献
709.
地震灾害间接经济损失估计 总被引:6,自引:0,他引:6
在分析了企业震后经济发展模式基础上,认为地震灾害间接经济损失由企业停减产短期影响损失、企业停减产长期影响损失、企业间产业关联损失及投资溢价损失四部分构成,提出了相应的估算方法,并以山东某一城市为例进行了地震灾害间接经济损失估计. 相似文献
710.
灾害经济损失概念及产业关联型间接经济损失计量 总被引:19,自引:0,他引:19
从三个方面拓展了对自然灾害经济的理解,它们是:承灾体,经济损失中的价格与价值,间接经济损失类型。评述了国内迄今提出的关于自然灾害产业关联型间接经济损失的计算方法,同时提出了作者对这一问题的处理,并以中国90年代的水旱灾害为例,计算了这一期间的平均年度产业关联型间接经济损失及经济损失总值。 相似文献