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991.
人工湿地的生态休闲利用与设计 总被引:4,自引:0,他引:4
人工湿地系统除了可以起到净化污水的作用,在经过精心设计后,还可发挥与自然湿地系统同样的生态保护功能,更可为人们提供一个休闲娱乐、旅游观光、科教科研的场所,越来越多的人工湿地系统开始重视并采用一系列的设计手段以充分发挥其自然价值和社会价值。本文详细地介绍了目前人工湿地综合利用研究进展,分析了综合利用时一些潜在的问题,及其设计时应当加以考虑的注意事项和建议。 相似文献
992.
安徽省沿江湿地资源现状、问题与对策 总被引:4,自引:0,他引:4
分析了安徽沿江湿地资源现状,揭示了沿江湿地资源丰富、生态价值高的特征,探讨了湿地开发利用过程中引发的生态环境问题,认为围湖造田和水土流失造成河湖淤塞是沿江湿地洪涝灾害频繁、湿地被破坏的主要原因,生物资源利用过度、追求经济快速发展和缺乏有效监督协调机制是生态系统退化的重要原因,最后提出调整产业结构、改变利用方式、建立湿地保护政策体系和协调机制、恢复湿地系统的生态功能等相应的对策与措施. 相似文献
993.
994.
Arnold L. O'Brien Ward S. Motts 《Journal of the American Water Resources Association》1980,16(5):785-789
ABSTRACT: Wetlands occur in a variety of geologic, hydrologic, and topographic settings and exhibit diverse hydrogeologic characteristics. A wetland is more than an organic mat - it is an element in a larger hydrogeologic system. Three distinct but related effects of wetlands are: modifying the character of runoff from a basin, influencing the discharge/recharge relationship with the underlying aquifer, and effecting the potential for ground water development in a wetland dominated basin. An important goal of wetland research is to define the diverse roles that wetlands play in the regional hydrology and to define the geologic, hydrologic, and topographic factors that will allow meaningful distinctions among wetlands. Geologic and hydrologic factors include character and thickness of surficial materials; bedrock type; hydrologic position; permeability of organic layer; transmissivity, quality, and hydrologic connection of wetland related aquifers; ground water outflow; and depth of standing water. Topographic factors are position in the drainage basin, relative size, and absolute size of wetlands. A wetland classification to aid hydrologists and land use planners is proposed using selected factors involving hydrologic position, topographic position, and geologic type. 相似文献
995.
Construction of 653 ha of salt marsh habitat from dredged material near the Aransas National Wildlife Refuge, Texas, has been
proposed, with the goal of increasing the area of habitat available to endangered whooping cranes (Grus americana). We assessed prototype created wetlands, and their similarity to natural reference sites, in terms of topography, vegetation,
and hydrology. The created sites were steeply sloped relative to natural sites and were dominated by monotypic stands of Spartina alterniflora. Natural sites were dominated by vegetation more tolerant of desiccation and hypersalinity and by unvegetated salt pans.
Differences in vegetation communities and distributions of habitat types resulted from efforts to enhance habitat diversity
in created marsh cells through manipulation of marsh topography. However, the scale at which this diversity occurred in natural
marsh of the study area was not considered. When constructing wetlands in cellular configurations, we recommend creation of
large complexes of adjoining, hydrologically linked, cells wherein the desired habitat diversity is created at the scale of
the entire complex, rather than within a single cell. Suggested design modifications would increase the similarity of created
marshes to natural reference sites, potentially improving habitat function. 相似文献
996.
997.
调整产业结构,保护四川省境内的黄河流域区生态环境 总被引:1,自引:0,他引:1
四川境内的黄河流域区为一个高寒牧业区,单纯的牧业经济给区域的生态环境造成了很大破坏,特别是草场退化、沙化、沼泽干涸,致使区域内水源涵养功能及其它生态功能的下降,危及黄河流域及国家的生态安全。因此,必须调整区域的产业结构,改变单一的牧业经济,减轻对生态系统的压力。产业结构调整的关键在于提高草地畜牧业经济的“质” 而非“量”;一方面应加强牲畜优良品种的培育和推广,使牲畜的肉、皮、毛、绒、骨等经济价值得以高质量。高效益地转化;另一方面,要立体开发草原经济,实行多业并举,使区域经济与生态环境保护协调发展。 相似文献
998.
湿地综述与新疆湿地研究 总被引:2,自引:0,他引:2
湿地(Wetland)是世界上面积最大、分布地域最广泛、生产力最高的景观类型之一,其结构和功能十分独特,对全人类的发展发挥着独特的作用。我国是一个干旱缺水严重的国家,我国西部干旱区水资源与湿地问题突出,对湿地的研究应和"干旱区研究"并行。文中总结了国际与国内对湿地研究与发展状况和趋势,分析了新疆湿地的特征和类型,并提出了新疆湿地存在的问题和一些建议。 相似文献
999.
Virginia Carter Mary Keith Garrett Patricia T. Gammon 《Journal of the American Water Resources Association》1988,24(2):297-306
ABSTRACT: A weighted average method was used to analyze transition zone vegetation in the Great Dismal Swamp to determine if a more uniform determination of wetland boundaries can be made nationwide. The method was applied to vegetation data collected on four transects and three vertical layers across the wetland-to-upland transition zone of the swamp. Ecological index values based on water tolerance were either taken from the literature or derived from local species tolerances. Wetland index values were calculated for 25-m increments using species cover and rankings based on the ecological indices. Wetland index values were used to designate increments as either wetland, transitional, or upland, and to examine the usefulness of a provisional wetland-upland break-point. Most increments were designated wetland or transitional when all species were used. Removal of three or five ubiquitous species either gave a wider range of wetland index values with a more variable designation of increments or caused designation of increments to be similar for all layers. The use of locally-derived rankings showed the sensitivity of the weighted averages method to ecological indices of species with large importance values. The weighted average method did not provide for an objective placement of an absolute wetland boundary, but did serve to focus attention on the transitional boundary zone where supplementary information is necessary to select a wetland-upland breakpoint. 相似文献
1000.
Charles T. Roman Robert A. Zampella Andrew Z. Jaworski 《Journal of the American Water Resources Association》1985,21(6):1005-1012
Wetland protection regulations and guidelines often require the delineation of precise wetland boundaries on a case-by-case basis. In this study, conducted in the New Jersey Pinelands, an ecological characterization of vegetation composition, soil and hydrologic relationships along upland to wetland Pinus rigida - dominated transittions provided the basis for a multiparameter approach to wetland boundary delineation. The transitional data set was analyzed by direct gradient analysis, cluster analysis and ordination. It is concluded that vegetation composition can be a principal factor in delineating wetland boundaries along natural upland to wetland transitions. However, where distinct vegetation changes are not observed, a feature of our study sites, a multiparameter approach should be used. 相似文献