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41.
南水北调对汉江中游襄樊市生态环境影响研究 总被引:1,自引:0,他引:1
南水北调中线工程实施后。对汉江中下游地区农业灌溉、城市发展、工业生产、航运、水质以及生态环境等产生较大的影响.分析和评价了中线工程对汉江中游襄樊市生态环境的影响,并提出了一些相应对策:进行生态环境安全规划、管理;兴建崔家营、新集水利枢纽工程;加强水污染控制和生态环境保护;加大水土保持力度,发展生态农业、生态林业、生态旅游业.确保生态环境建设的持续性、安全性和高效益性,使南水北凋中线工程调水给襄樊市造成的影响降到最低限度。促进襄樊市社会经济生态环境的可持续发展. 相似文献
42.
南淝河水环境质量的改进密切值法综合评价 总被引:2,自引:0,他引:2
密切值法是多目标决策中的一种优选法,它适用于多测点、多指标的质量评价;水环境是一个多因素、多因子的复合体,因此可以用密切值法来进行评价。文章对合肥市南淝河水环境质量用密切值法进行了综合评价,评价项目取该河14个监测点的主要污染物CODcr、TP及NH3-N等3项监测指标作为评价因子,得出了评价结果并对污染程度进行了排序;与向量模评价法进行比较,结果表明该方法切实可行。 相似文献
43.
闽南地区农村住宅安全性现状及防灾建议 总被引:1,自引:0,他引:1
在对厦门市海沧区近9 000栋农村住宅的安全性和耐久性现状普查基础上,分析该地区农村住宅的结构类型分布特点和不同类型房屋的安全性等级分布.针对该地区农村住宅存在的安全性和耐久性问题,提出该地区农村住宅防御自然灾害,特别是防御地震灾害的相关建议. 相似文献
44.
Cecilia Ferreyra 《Systemic Practice and Action Research》2006,19(6):577-598
In the last few decades, there has been a trend towards increased stakeholder and public participation in natural resource management in North America. To a certain extent, the rationale for this trend is found in the complexity and uncertainty of environmental issues, which confront us with the coexistance of multiple legitimate values and perspectives in society. Recognizing this “epistemological plurality” has important implications for both policy and science. In this paper, I critically reflect on my experiences as a doctoral student engaged in participatory action research (PAR) with a watershed partnership in Ontario, Canada. In providing this biographical account, I seek to make a contribution to ongoing discussions regarding the nature, challenges and benefits of this methodological approach for academic research, as well as to emerging debates on PAR in the context of environmental governance and “post-normal” approaches to natural resource management.
相似文献
Cecilia FerreyraEmail: |
45.
国际临界带研究发展回顾与美国临界带研究进展介绍 总被引:1,自引:0,他引:1
基于对临界带国际发展态势的分析,梳理了临界带的概念;回顾了国际临界带研究的发展历程;并重点对美国在临界带研究方面的进展及其已经部署的6个临界带观测站进行了详细的介绍。 相似文献
46.
《Journal of Natural History》2012,46(33):3059-3074
In the course of our examination of samples of Cladocera from South America and subantarctic islands in the collection of the Swedish Museum of Natural History, Stockholm, we found some type material of Sven Ekman, unrecognized earlier, as well as other samples described in his publications (Ekman 1900, 1905). A single specimen of Pleuroxus scopuliferus Ekman, 1900, apparently seen by its author, is re‐deposited as the lectotype, while the neotype of this taxon earlier selected by Frey (1993) must be rejected according to ICZN (2000). Daphnia cavicervix Ekman, 1900 is redescribed based on numerous parthenogenetic, ephippial females and males, and lectotype and paralectotypes are selected. Some recent problems of systematics of Daphnia in South America are discussed. 相似文献
47.
《Journal of Natural History》2012,46(31):2935-2952
The scales of one high Andean eumaeine lycaenid butterfly species with pale dorsal coloration and four species with vivid dorsal colour were investigated using field emission scanning electron microscopy. The micro‐ and nanostructures are illustrated, described, measured, and interpreted. The vivid colours in the species are caused by a pepper‐pot nanostructure of Urania‐type scales. This nanostructure is a three‐dimensional lattice within the body of the individual scale. The scales of the non‐vivid orange species are lacking this nanostructure and the surfaces of their scales show high microstructure irregularities. This absence of vivid colour may be correlated with thermal regulation. The irregularity of the scale microstructures suggests a heavy environmental pressure on the populations sampled. Previously unknown structural variations of Urania‐type scales are also described. The existence of closed scale microcell structures, explained as an apomorphic character in the tribe Eumaeini, most probably evolved independently several times. It is hypothesized that scale micro‐ and nanostructure modifications develop syntopically within a population, which in turn can lead to rapid diversification. 相似文献
48.
《Journal of Natural History》2012,46(37-38):2237-2253
Four nominal species of the genus Horatia Bourguignat, 1887 were described by Russian authors from Caucasian caves (H. borutzkii Shadin, 1932, H. birsteini Starobogatov, 1962, H. ljovushkini Starobogatov, 1962 and H. sokolovi Starobogatov, 1962). Hitherto all the species were known from type series (presented by empty shells) only. Examination of newly obtained samples from the caves of South Caucasus has shown that the four species actually do not belong to the genus Horatia due to obvious differences in the morphology of the copulatory organs between H. klecakiana Bourguignat, 1887 (the type species of this genus) and the Caucasian snails. Moreover, statistical analysis of conchological variation has revealed that the species H. birsteini, H. ljovushkini, and H. sokolovi are conspecific. Two genera are described: Pontohoratia (includes P. birsteini and P. smyri sp. nov.) and Motsametia (with the single species M. borutzkii comb. nov.). The two genera can be distinguished on the basis of the structure of their copulatory organs. The distribution and ecology of the Caucasian Horatia-like mollusks are briefly outlined.http://zoobank.org/urn:lsid:zoobank.org:pub:4EDFB2AE-CB1D-4113-8CC7-3A1BBB46D838 相似文献
49.
《Journal of Natural History》2012,46(29-30):1911-1919
In 2001 the Soil Biodiversity Group of the Natural History Museum, London collected Oligochaeta material from bromeliad epiphytes and litter samples in Belize. This material remained unidentified until being passed to the Annelida curator in 2010. Elaborating this material resulted in discovery of two earthworm species new to science Eutrigaster (Graffia) georgei sp. nov. and Kaxdrilus sherbutti sp. nov. belonging to the family Acanthodrilidae (Benhamiinae) and Acanthodrilidae (Acanthodrilinae) respectively. http://www.zoobank.org/urn:lsid:zoobank.org:pub:6BEB9E5A-7D54-4E48-913D-EF76D7DACC16 相似文献
50.