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291.
北京山区生态系统稳定性评价模型初步研究 总被引:5,自引:0,他引:5
李晓秀 《生态与农村环境学报》2000,16(1):21-25
在建立北京山区生态评价体系的基础上,参考有关资料和北京的实际状况确定山区生态系统稳定性评价的标准和分级,选择适当的方法确定评价因子的层次关系和重要度,建立了综合评价模型。并以北京山区的一典型区为例对评价模型进行检验,结果与实际基本相符。 相似文献
292.
Circular agriculture is an essential way to realize the positive recycling of ecology and harmonious development of the country construction.The sustainable development of Beijing’s mountain areas depends on the background and orientation of ecological economy.Beijing’s mountain areas bear the responsibility of protecting the ecological safety of the whole Beijing district and also the exploration of circular agriculture in mountain areas is very important to promote the sustainable use of agriculture resou... 相似文献
293.
Paolo Tremolada Marco Parolini Cristiano Ballabio Alfredo Provini 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3298-3307
Soils are the main reservoirs of POPs in mountain ecosystems, but the great variability of the concentrations, also at small scale, leaves some uncertainties in the evaluation of environmental burdens and exposure. The role of the aspect of the mountain side and the seasonal variation in the contamination levels was analysed by means of several soil samples taken from central Italian Alps. A greater contamination content was present in northern soils with a mean ratio between the north vs. south normalised concentration of around a factor of 2 (North-South Enrichment Factor). Experimental factors agreed with theoretical calculations based on temperature-specific calculated Ksa values. From May to November consistent differences in normalised concentrations up to 5-fold were observed. A dynamic picture of the POP contamination in high altitudinal soils is derived from the data in this work, with spring-summer half-lives between 60 and 120 days for most of the compounds. 相似文献
294.
利用衡阳市2006年山洪灾情数据,引入综合灾情指数对湖南省衡阳市山洪灾害进行综合灾情损失评估,得出耒阳市的综合灾情指数最大;灾情重的直接原因是暴雨大,水位短时间上升快。同时,暴雨-山体滑坡-泥石流灾害链放大了灾情;农村地区防灾减灾意识淡薄、防洪工程标准偏低以及减灾措施不当也加剧了山洪灾情。为此,要通过加强工程建设与山洪灾害危险性宣传来提高农村抗灾能力,达到安全减灾目的。 相似文献
295.
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297.
欠发达资源富集山区的生态文明发展模式与对策建议 总被引:1,自引:0,他引:1
沈镭 《长江流域资源与环境》2011,20(4):501-507
结合国内外区域经济发展经验和黔东南实地调研情况,分析了欠发达资源富集区和山区资源开发的一些基本特征,指出了黔东南山区的生态价值和经济价值,认为开展生态文明建设是黔东南这样欠发地区实现经济与生态双赢的理想选择。黔东南州是我国经济欠发达、资源富集、生态优质、少数民族文化独特的典型山区,具有原形的自然生态、原始的民族文化、原貌的历史遗存,其生态价值具有十分明显的比较优势。生态文明是指人与自然和谐共荣的文化价值取向、生态系统良性发展下的可持续生产、满足人类自身需要又不损害自然系统的可持续消费的一种社会形态。提出了黔东南发展生态农业、生态工业循环经济、生态旅游、生态城镇和政府绿色管理等具体发展模式,最后从宣传教育、科技创新、特色经济、生态产业链和低碳经济等提出了若干对策建议。 相似文献
298.
van Drooge BL López J Fernández P Grimalt JO Stuchlík E 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1234-1240
European alpine lake systems are used as indicators of air quality over the continent. Preliminary data showed high polycyclic aromatic hydrocarbons (PAH) loads in the High Tatras (Eastern Europe) in comparison to other mountain regions. Here, insight on the spatial distribution of PAH is provided from analysis of top-core sediments of 27 alpine lakes distributed along the High Tatras.Top-core sediment concentrations were higher than those in deep-cores, and they were higher than those observed in other European high mountain regions. The PAH profiles were uniform and comparable to those observed in aerosols and snow, indicating that atmospheric deposition was the predominant PAH input pathway to the lakes. Good agreement between estimated atmospheric deposition and sedimentation fluxes was observed. However, in several lakes in the western range higher sediment fluxes may correspond to higher PAH depositions levels. The higher concentrations may also reflect inputs from potential emission source areas. 相似文献
299.
坡耕地严重的水土流失对山区农业的可持续发展构成了极大的威胁,滇东北山区因其人口众多,大面积的坡耕地水土流失十分严重,而长期处于贫困。本文针对滇东北山区基本现状而进行的坡耕地生态环境治理的初步探讨。 相似文献
300.
L. Ruby Leung Mark S. Wigmosta 《Journal of the American Water Resources Association》1999,35(6):1463-1471
ABSTRACT: Global climate change due to the buildup of greenhouse gases in the atmosphere has serious potential impacts on water resources in the Pacific Northwest. Climate scenarios produced by general circulation models (GCMs) do not provide enough spatial specificity for studying water resources in mountain watersheds. This study uses dynamical downscaling with a regional climate model (RCM) driven by a GCM to simulate climate change scenarios. The RCM uses a subgrid parameterization of orographic precipitation and land surface cover to simulate surface climate at the spatial scale suitable for the representation of topographic effects over mountainous regions. Numerical experiments have been performed to simulate the present-day climatology and the climate conditions corresponding to a doubling of atmospheric CO2 concentration. The RCM results indicate an average warming of about 2.5°C, and precipitation generally increases over the Pacific Northwest and decreases over California. These simulations were used to drive a distributed hydrology model of two snow dominated watersheds, the American River and Middle Fork Flathead, in the Pacific Northwest to obtain more detailed estimates of the sensitivity of water resources to climate change. Results show that as more precipitation falls as rain rather than snow in the warmer climate, there is a 60 percent reduction in snowpack and a significant shift in the seasonal pattern of streamflow in the American River. Much less drastic changes are found in the Middle Fork Flathead where snowpack is only reduced by 18 percent and the seasonal pattern of streamflow remains intact. This study shows that the impacts of climate change on water resources are highly region specific. Furthermore, under the specific climate change scenario, the impacts are largely driven by the warming trend rather than the precipitation trend, which is small. 相似文献