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101.
The Natural Vegetation Responses to the Groundwater Change Resulting from Ecological Water Conveyances to the Lower Tarim River 总被引:4,自引:0,他引:4
This paper takes the ecological water conveyance project (EWCP) that transfers water from the Bosten Lake, to Daxihaizi Reservoir, and finally to the Taitema Lake as a case study to analyze
the dynamic change of the groundwater depth, the vegetation responses to the elevation of the groundwater depth as well as
the relationship between the groundwater depth and the natural vegetation. The results from many years’ monitoring in field
indicate: (1) the groundwater depth has been elevating gradually with the increase in the times of watering and the elevation
range has been expanding continuously in the lower reaches of Tarim River. Correspondingly, the natural vegetation has a favorable
response to the elevation of the groundwater depth. The change of the natural vegetation has accordance with that of the groundwater
depth. Such facts not only show that groundwater is a key factor to the growth of the native vegetation but also prove it
is feasible that the degraded ecosystem can be restored and protected by the EWCP; (2) the results of analysis of the spatial-temporal response of the natural vegetation to watering reveals that the beneficial
influence of the EWCP on the ecosystem in the lower Tarim River is a long-term process; (3) in terms of the function and structure of ecosystem
after watering in the lower reaches of Tarim River, the EWCP does not still reach the goal of ecological restoration at a large spatial scale at present. Based on such monitoring results,
some countermeasures and suggestions for the future restoration strategy are proposed so as to provide a theoretical basis
for restoring and protecting the ecosystem in Tarim River, and meanwhile it can also provide some scientific references for
implementing the similar ecological projects in other areas. 相似文献
102.
The work is devoted to the investigation of nonlinear singular ecological models with initial functional conditions and determination of solutions of problems, which are connected with these models. It is also considered some of its applications in field of ecological modelling under formulation and investigation of the so-called keeping and protection problems. We shall investigate nonlinear models that are described with the help of partial differential equation of first and second orders. Solutions of linear and some singular nonlinear problems with functional initial conditions are obtained in the form depending from initial parameters. 相似文献
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阐述了生态文明的内涵,认为生态文明入法是思想理念上升为法律意志,分析了生态文明入法的必要性、合理性和价值性。 相似文献
107.
108.
Claire Beausoleil Jean-Nicolas Ormsby Andreas Gies Ulla Hass Jerrold J. Heindel Marie Louise Holmer Pia Juul Nielsen Sharon Munn Gilbert Schoenfelder 《Chemosphere》2013
A workshop was held in Berlin September 12–14th 2012 to assess the state of the science of the data supporting low dose effects and non-monotonic dose responses (“low dose hypothesis”) for chemicals with endocrine activity (endocrine disrupting chemicals or EDCs). This workshop consisted of lectures to present the current state of the science of EDC action and also the risk assessment process. These lectures were followed by breakout sessions to integrate scientists from various backgrounds to discuss in an open and unbiased manner the data supporting the “low dose hypothesis”. While no consensus was reached the robust discussions were helpful to inform both basic scientists and risk assessors on all the issues. There were a number of important ideas developed to help continue the discussion and improve communication over the next few years. 相似文献
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腐蚀性环境与自动控制设备的保护 总被引:1,自引:0,他引:1
介绍了环境空气中腐蚀住气体对电子仪器和自动控制设备的腐蚀机理与防护方法.腐蚀产生的原因主要是直接氧化和电化学过程.腐蚀性环境通常根据腐蚀性气体的反应性进行分级.环境空气的腐蚀性可通过控制环境条件和空气净化去除。 相似文献