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431.
Ecological-Economic Modeling for Biodiversity Management: Potential, Pitfalls, and Prospects 总被引:3,自引:0,他引:3
FRANK WÄTZOLD††† MARTIN DRECHSLER CLAIRE W. ARMSTRONG† STEFAN BAUMGÄRTNER‡ VOLKER GRIMM REAS HUTH CHARLES PERRINGS§‡‡‡ HUGH P. POSSINGHAM JASON F. SHOGREN†† ERS SKONHOFT‡‡ JANA VERBOOM-VASILJEV§§ CHRISTIAN WISSEL 《Conservation biology》2006,20(4):1034-1041
Abstract: Ecologists and economists both use models to help develop strategies for biodiversity management. The practical use of disciplinary models, however, can be limited because ecological models tend not to address the socioeconomic dimension of biodiversity management, whereas economic models tend to neglect the ecological dimension. Given these shortcomings of disciplinary models, there is a necessity to combine ecological and economic knowledge into ecological-economic models. It is insufficient if scientists work separately in their own disciplines and combine their knowledge only when it comes to formulating management recommendations. Such an approach does not capture feedback loops between the ecological and the socioeconomic systems. Furthermore, each discipline poses the management problem in its own way and comes up with its own most appropriate solution. These disciplinary solutions, however, are likely to be so different that a combined solution considering aspects of both disciplines cannot be found. Preconditions for a successful model-based integration of ecology and economics include (1) an in-depth knowledge of the two disciplines, (2) the adequate identification and framing of the problem to be investigated, and (3) a common understanding between economists and ecologists of modeling and scale. To further advance ecological-economic modeling the development of common benchmarks, quality controls, and refereeing standards for ecological-economic models is desirable. 相似文献
432.
This study evaluated the potential toxicological risk posed to human health due to the exposure to heavy metals by water ingestion
in an area affected by tanneries – the Cadeia-Feitoria hydrographic basin (Brazil). River water was collected at 10 sites,
every 3 months, from July 1999 to April 2000. After acid digestion, total metal concentration was determined by inductively
coupled plasma optical emission spectrometry (Cd, Cu, Cr, Ni, Zn), flame atomic absorption (Al, Fe, Pb, Mn), or cold vapor
atomic absorption spectrometry (Hg). Cr(VI) was complexed with diphenyl-carbazide and detected by UV–vis spectrometry. In
order to quantify the risk of exposure, the risk assessment methodology employed by the Environmental Protection Agency of
the United States was applied at a screening level. The assumed scenarios included extreme exposure patterns (ingestion of
untreated water, conversion of Cr(III) to Cr(VI), temporal peaks of pollution). Fe, Al, Cd, Hg, and Pb were not included in
the risk analysis, since they showed a low toxicity potential or were undetected in the samples. The selected metals presented
Hazard Quotients < 1, in the following order of increasing risk: Cu < Cr(III) < Zn < Ni < Mn < Cr(VI). Hazard indexes, representing
the additive effect of contaminants, were also low in the basin (< 1), but comparatively increased in the lower reach of Feitoria
and Cadeia Rivers. Although noncarcinogenic risk levels did not suggest possible adverse toxicological effects to the human
population, a considerable deviation from background conditions was observed downstream the area where tanneries are mainly
located. 相似文献
433.
本文提出利用环境功能指数对城市环境功能区的环境功能进行评估,设计了相应的评估方法,以马鞍山市七个环境功能区为例进行了实例分析,讨论了各功能区的环境功能变化趋势,并提出了相应的对策与建议。 相似文献
434.
435.
436.
SANJIB Kumar Das DIBYENDU Biswas SUDIPTO Roy 《应用与环境生物学报》2007,13(5):662-667
The benthic macroinvertebrate communities of two lotic aquatic habitats,namely,the Churni River(C-R)and the Jalangi River(J-R)were compared in this study.One lotic aquatic system(C-R)was polluted by organic pollutants due to discharge of unprocessed sewage water,while the other(J-R)was not affected by such pollution.Evaluations of various physico-chemical properties of water,sediment and different macroinvertebrate communities of the two tropical lotic systems were done in a period from January,2002 to December,2003.A long term temporal change in the macroinvertebrate communities was recorded due to increase in sediment rH value.Sediment redox potential affected by the anthropogenic activities was found to be an important factor for alteration of macroinvertebrate communities in these aquatic ecosystems.A positive correlation has been established between rH and Margalef index in this study.Potassium and the total count of coliform bacteria in water showed significantly higher values for the polluted Churni River than those for the Jalangi River.Fig 3,Tab 4,Ref 34 相似文献
437.
京杭运河徐州段底栖动物与水质的关系 总被引:7,自引:0,他引:7
本研究利用生物监测方法,探明了京杭运河徐州段大型底栖无脊椎动物的生物种群及其分布。运用污染生物指数(Goodnight)和生物多样性指数(Shannon)统计表达,对京杭运河徐州段进行生物综合评价,同时,指出了该水体污染,将给徐州的两个地面饮用水厂及国家南水北调工程带来威胁和危险。通过生物指标与理化指标对比,综合分析研究,冲破了理化指标的限制,说明生物指标对水体污染的评价更全面、可靠而直观。 相似文献
438.
关于肥满度指数的讨论 总被引:19,自引:0,他引:19
肥满度指数,也称身体状况指数,广泛应用于各个动物类群和生态学、生理、生化、遗传学以及养殖业.至今已有多种肥满度指数提出,从计算公式结构上,肥满度指数可以划分为比值法和残差法两大类.通过对各种肥满度指数的分析,Le Cren相对状态指数Kn、log10(体重)与log10(身体大小指数)线性回归的(标准化)残差这两种肥满度指数系统误差相对较小.实际应用中最好根据所考察的问题分别计算不同年龄段、性别的个体的肥满度指数来分析肥满度指数.由于定义的模糊性及其前提假设缺乏广泛验证,因此,肥满度指数在实际应用中需要谨慎考察其前提假设是否满足.参33 相似文献
439.
Utility of Mitochondrial DNA Barcodes in Species Conservation 总被引:9,自引:0,他引:9
DANIEL RUBINOFF 《Conservation biology》2006,20(4):1026-1033
Abstract: Molecular tools are a standard part of many conservation studies and can be informative at many different levels of analysis, although there are inherent limitations and strengths of different genes or parts of genes to inform specific questions. Animal DNA barcodes, 600- to 800-base-pair segments of the mitochondrial gene cytochrome oxidase I, have been proposed as a means to quantify global biodiversity. Although mitochondrial (mt) DNA has a long history of use at the species level, recent analyses suggest that the use of a single gene, particularly mitochondrial, is unlikely to yield data that are balanced, universally acceptable, or sufficient in taxonomic scope to recognize many species lineages. Mitochondrial and nuclear genomes have different patterns of evolution and modes of inheritance, which can result in very different assessments of biodiversity. The ramifications of choosing a particular definition of species (species concept) need to be carefully considered because current efforts have designated DNA barcodes as the universal species concept without demonstrating its superiority over preexisting concepts. The results of such a barcoding paradigm may include a failure to recognize significant portions of biodiversity or nuclear/mitochondrial mixed lineages and could spuriously focus conservation resources on populations with relatively minor mtDNA divergence. DNA barcodes are most likely to provide potentially useful information for groups that are already well studied, and such taxa do not constitute the majority of biodiversity or those in most need of research attention. DNA barcode-length sequences are an important source of data but, when used alone or out of context, may offer only a fraction of the information needed to characterize species while taking resources from broader studies that could produce information essential to robust and informed conservation decisions. 相似文献
440.
A Global Indicator for Biological Invasion 总被引:2,自引:0,他引:2
Abstract: "Trends in invasive alien species" is one of only two indicators of threat to biodiversity that form part of the Convention on Biological Diversity's (CBD) framework for monitoring progress toward its "2010 target" (i.e., the commitment to achieve by 2010 a significant reduction in the current rate of biodiversity loss). To date, however, there is no fully developed indicator for invasive alien species (IAS) that combines trends, derived from a standard set of methods, across species groups, ecosystems, and regions. Here we provide a rationale for the form and characteristics of an indicator of trends in IAS that will meet the 2010 framework goal and targets for this indicator. We suggest single and composite indicators that include problem-status and management-status measures that are designed to be flexible, readily disaggregated, and as far as possible draw on existing data. The single indicators at national and global scales are number of IAS and numbers of operational management plans for IAS. Global trends in IAS are measured as the progress of nations toward the targets of stabilizing IAS numbers and the implementation of IAS management plans. The proposed global indicator thus represents a minimum information set that most directly addresses the indicator objective and simultaneously aims to maximize national participation. This global indicator now requires testing to assess its accuracy, sensitivity, and tractability. Although it may not be possible to achieve the desired objective for a global indicator of biological invasion by 2010 as comprehensively as desired, it seems possible to obtain trend estimates for a component of the taxa, ecosystems, and regions involved. Importantly, current indicator development initiatives will also contribute to developing the mechanisms necessary for monitoring global trends in IAS beyond 2010. 相似文献