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江苏沿海互花米草盐沼湿地的经济、生态功能 总被引:12,自引:1,他引:12
沈永明 《生态经济(学术版)》2001,(9):72-73,86
互花米草是从美国引进我国的新物种,自1982年在江苏沿海栽种以来,在江苏沿海已形成了约125km^2的互花米草盐沼湿地。本文分析了互花米草盐沼湿地的生态、经济价值,讨论了互花米草盐沼湿地对环境的影响,指出必须对互花米草代盐沼作进一步深入研究。 相似文献
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Steven T.A. Timmermans Shannon S. Badzinski Joel W. Ingram 《Journal of Great Lakes research》2008,34(2):351-364
We used Great Lakes hydrologic data and bird monitoring data from the Great Lakes Marsh Monitoring Program from 1995–2002 to: 1) evaluate trends and patterns of annual change in May-July water levels for Lakes Ontario, Erie, and Huron-Michigan, 2) report on trends of relative abundance for birds breeding in Great Lakes coastal marshes, and 3) correlate basin-wide and lake-specific annual indices of bird abundance with Great Lakes water levels. From 1995–2002, average May, June, and July water levels in all lake basins showed some annual variation, but Lakes Erie and Huron-Michigan had identical annual fluctuation patterns and general water level declines. No trend was observed in Lake Ontario water levels over this period. Abundance for five of seven marsh birds in Lake Ontario wetlands showed no temporal trends, whereas abundance of black tern (Chlidonias niger) declined and that of swamp sparrow (Melospiza georgiana) increased from 1995–2002. In contrast, abundances of American coot (Fulica americana), black tern, common moorhen (Gallinula chloropus), least bittern (Ixobrychus exilis), marsh wren (Cistorthorus palustris), pied-billed grebe (Podilymbus podiceps), sora (Porzana carolina), swamp sparrow, and Virginia rail (Rallus limicola) declined within marshes at Lakes Erie and Huron/Michigan from 1995–2002. Annual abundances of several birds we examined showed positive correlations with annual lake level changes in non-regulated Lakes Erie and Huron/Michigan, whereas most birds we examined in Lake Ontario coastal wetlands were not correlated with suppressed water level changes of this lake. Overall, our results suggest that long-term changes and annual water level fluctuations are important abiotic factors affecting abundance of some marsh-dependent birds in Great Lakes coastal marshes. For this reason, wetland bird population monitoring initiatives should consider using methods in sampling protocols, or during data analyses, to account for temporal and spatial components of hydrologic variability that affect wetlands and their avifauna. 相似文献
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The most important factor in shoreline wetlands is variation in water depth. Superimposed upon this are gradients of soil fertility, ranging from sandy, open shorelines to sheltered, fertile bays. The use of both transplant and pot experiments shows that competitive hierarchies rapidly arise in wetland vegetation and that species are sorted along exposure and depth gradients according to their relative competitive abilities. These patterns can be summarized in the centrifugal organization model, in which competitive dominants occupy preferred core habitats and where different species and vegetation types are then arrayed outward along different constraint gradients ( Wisheu & Keddy 1992 ). Knowledge of these general patterns provides an essential tool for managing lakes and reservoirs in order to maintain and enhance biological diversity. 相似文献
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农民收入水平对农村家庭能源消费结构影响的实证分析 总被引:17,自引:0,他引:17
本文依据调查资料,利用层次分析法实证分析了农民收入水平对农村家庭能源消费结构的影响,得出结论:农户的收入水平对农村家庭生活用能源种类的选择影响较大,因此不同收入水平的农户家庭能源消费的结构存在较大的差异;人均收入在4000元以下的农户,户用沼气的权系数最大,人均收入超过4000元的农户,液化气的权系数最大;农户的收入越高,对能源的舒适性、便利性、卫生特性的要求越高,农户的收入越低,对能源的经济性则考虑得越多;使用无成本、又便利的户用沼气非常适合在收入水平较低的农村地区推广。 相似文献
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鄱阳湖控制工程对自然保护区生态环境的影响 总被引:2,自引:0,他引:2
鄱阳湖是长江流域的一大淡水湖泊,其水旱灾害相当频繁,长期以来,国家和地方政府十分重视鄱阳湖洪涝灾害的治理研究工作,逐步形成了以鄱阳湖控制工程为代表的治理方案,该控制工程实施后,其水位将常年维持在16.0-18.0m之间,这将直接淹没16.0m以下的然状态下随着枯洪季节在而变化形成的的草滩、沼泽和浅水洼地等独特湿地自然景观,其自然环境将发生变化,使湖泊水域增大,洲滩,湿地大面积减少,从而对国家级鄱阳湖候鸟自然保护区生态环境带来严重不利影响。 相似文献
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初探三峡水库湿地面临的问题及其对策 总被引:4,自引:0,他引:4
三峡水库建成后,将成为我国最大的人工湿地,库长约650km,平均水面宽1 500m,具有脆弱性、不稳定性及其多功能性的特征;分析了三峡水库湿地面临的3个问题:水污染现状及新污染问题的预测、泥沙淤积及其发展态势、生物多样性危机及其增多的趋势;提出了保证三峡水库湿地可持续利用的措施:制定三峡湿地地方性保护法、建立国家级湿地自然保护区、加强三峡湿地重要性的宣传教育、提高公众保护意识及搞好长江上游生态恢复重建等。 相似文献