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551.
由文辉 《生态与农村环境学报》1997,(3)
淀山湖是上海市唯一的淡水湖泊,面积约62km2。淀山湖湿地的形成主要是地质、地貌、气候、水文等自然因素和人类活动影响长期相互作用的结果。本文着重讨论了淀山湖湿地的生产功能和环境生态功能,并对湖泊湿地的利用与保护提供了建议。 相似文献
552.
王献薄 《生态与农村环境学报》1995,(2)
景观作为自然与人类相互作用的一个基本单位,目前正在发生剧烈的变化。许多传统的文化建筑和土地利用方式和格局正在走向衰亡,景观的多样性和丰富性受到前所未有的威胁,常常被千篇一律的大片单调的景色所代替。本文主要讨论下列三个问题:景观的基本含义及其保护,景观保护的主要任务;景观保护是区域发展的基础。 相似文献
553.
554.
Utility of Dynamic-Landscape Metapopulation Models for Sustainable Forest Management 总被引:5,自引:0,他引:5
BRENDAN A. WINTLE§ SARAH A. BEKESSY† LISA A. VENIER‡ JENNIE L. PEARCE‡ RYAN A. CHISHOLM 《Conservation biology》2005,19(6):1930-1943
Abstract: We evaluated the utility of combining metapopulation models with landscape-level forest-dynamics models to assess the sustainability of forest management practices. We used the Brown Creeper ( Certhia americana ) in the boreal forests of northern Ontario as a case study. We selected the Brown Creeper as a potential indicator of sustainability because it is relatively common in the region but is dependent on snags and old trees for nesting and foraging; hence, it may be sensitive to timber harvesting. For the modeling we used RAMAS Landscape, a software package that integrates RAMAS GIS, population-modeling software, and LANDIS, forest-dynamics modeling software. Predictions about the future floristic composition and structure of the landscape under a variety of management and natural disturbance scenarios were derived using LANDIS. We modeled eight alternative forest management scenarios, ranging in intensity from no timber harvesting and a natural fire regime to intensive timber harvesting with salvage logging after fire. We predicted the response of the Brown Creeper metapopulation over a 160-year period and used future population size and expected minimum population size to compare the sustainability of the various management scenarios. The modeling methods were easy to apply and model predictions were sensitive to the differences among management scenarios, indicating that these methods may be useful for assessing and ranking the sustainability of forest management options. Primary concerns about the method are the practical difficulties associated with incorporating fire stochasticity in prediction uncertainty and the number of model assumptions that must be made and tested with sensitivity analysis. We wrote new software to help quantify the contribution of landscape stochasticity to model prediction uncertainty. 相似文献
555.
城市生态系统的格局和过程 总被引:4,自引:0,他引:4
城市生态系统是人类活动影响下的复合生态系统。人为的开发利用活动和局地的生物物理条件形成了城市特有的景观格局。城市发展改变了自然的生物栖息环境,从根本上改变了生态系统的结构、过程、功能,以及所提供的各种服务。这种改变最终又会影响人类自身的健康生存。文章综述了国内外有关城市景观格局和和重要生态过程之间相互作用机制的研究进展。通过研究发现,在大尺度上,净初级生产力是衡量城市发展对区域物流、能流影响的有效指标;在小尺度上,城市物流、能流过程和城市内部的景观结构、格局有很强的相关性。城市发展显著的改变了自然的栖息地及生物生长过程,本地植被种类减少,外来种增加,外来种的数量和人口数量有显著的相关性;而城市动物群落主要由一些小型哺乳动物、无脊椎动物、鸟类、两栖爬行类动物组成,其中,鸟类是研究城市化过程的有效指示物种。城市生态系统特有的景观格局及生态等过程显著的改了局部区域的微气候和水文过程,城市气温增加,风速降低,云、雾量增加,地表径流增加,流速加大,污染负荷增强等。因此,控制人类活动,优化土地利用的结构和空间格局,是改善城市生态系统结构和过程,保证可持续发展的基本出发点。但是,目前有关城市-格局-过程之间的影响机制还不十分清楚,尤其是定量研究较少。因此,结合传统的城市生态学,景观生态学的理论和其他相关学科领域的发展,为深入分析城市格局-过程之间的关系提供了重要的研究前景。 相似文献
556.
本文分析了园林中水的形态类型及特征,从形状、声音、色泽和气味等论述了园林中水的艺术地位和审美特征. 相似文献
557.
G. P. Patil J. A. Bishop W. L. Myers C. Taillie R. Vraney Denice Wardrop 《Environmental and Ecological Statistics》2004,11(2):139-164
Geographical surveillance for hotspot detection and delineation has become an important area of investigation both in geospatial ecosystem health and in geospatial public health. In order to find critical areas based on synoptic cellular data, geospatial ecosystem health investigations apply recently discovered echelon tools. In order to find elevated rate areas based on synoptic cellular data, geospatial public health investigations apply recently discovered spatial scan statistic tools. The purpose of this paper is to conceptualize a joint role for these together in the spirit of a cross-disciplinary cross-fertilization to accomplish more effective and efficient geographical surveillance for hotspot detection and delineation, and early warning system. 相似文献
558.
改革开放以来,我国城市园林绿化事业虽然取得了长足进展,但仍面临着人多地少、资金严重缺乏的窘境,本文分析了产业这些问题的症结,提出了相应的对策与建议。 相似文献
559.
~~特变电工衡阳变压器有限公司环境景观设计构思@陈盛彬$湖南环境生物职业技术学院园林系!湖南衡阳421005
@陈景$湖南环境生物职业技术学院园林系!湖南衡阳421005
@谢振华$衡南县林业局!湖南衡阳421005~~~~~~ 相似文献
560.
Summary This contribution presents an attempt to measure the path of habitat and vegetation succession in a coastal dune system (Kenfig
Burrows, South Wales) using remote sensing and GIS. The loss of slack habitats associated with the continuing stabilization
of this dune system is a major cause for concern. These habitats support a range of plant species, including the rare fen
orchid,Liparis loeselii, as well as other hydrophytes. A decrease in their areal extent implies a reduction in biodiversity. To quantify the overall
rate and spatial dimension of these changes, a series of aerial photographs dating from 1962 to 1994 were digitized and analysed
in an image processing system. The resultant maps. transferred to a vector-based GIS, were used to derive a transition matrix
for the dune system over this period of time. The results indicate that there has been a marked reduction in the total area
of bare sand (19.6% of the dune system in 1962, but only 1.5% in 1994) and a decline in both the areal extent and the number
of dune slacks. Over the same period of time, there has been an increase inSalix repens dominated habitats, at the expense of pioneer species. Analysis of the habitat maps, together with hydrological data, within
the GIS suggests that even the dry slacks have the potential for further greening and to support invasive species. In terms
of habitat management however, there is still scope to restore many of the slacks to their original state. It is estimated
that at least 24% of the area occupied by partially and moderately vegetated slacks could be rehabilitated. 相似文献