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921.
《煤矿安全监察条例》与安全生产立法问题探讨   总被引:1,自引:1,他引:0  
基于对国务院 2 96号令《煤矿安全监察条例》和我国现行的安全生产法律、行政法规的全面比较分析 ,从执法主体、执法内容、执法监督及行政强制措施、即时强制和法律责任等 5个方面 ,研究、总结了《煤矿安全监察条例》在立法上的 13个特点及其对新时期安全生产立法的指导意义  相似文献   
922.
重大工业隐患的地域监控体系研究   总被引:6,自引:3,他引:3  
系统地分析了重大工业危险源与事故隐患 ;研究了地域监控、预警、应急预案的体系建设以及隐患监控的新技术应用基础 ;提出了职业安全卫生监控体系中的工业危险源和隐患监控。笔者认为 :应该分为过程安全监控和安全目标监控两个层次  相似文献   
923.
安全流变理论及其在煤矿事故中的应用   总被引:12,自引:5,他引:7  
提出了“安全流变理论”,分析了事物“安全流变”的基本特征和理论基础 ,描述了煤矿事故的安全流变特性 ,同时指出煤矿事故的发生和发展可以用“安全流变理论”进行解释 ,进而说明“安全流变理论”是符合事物发展变化规律的。  相似文献   
924.
洞庭湖区生态环境的问题与治理对策   总被引:5,自引:0,他引:5  
贺建林 《四川环境》2001,20(2):55-58
在广泛、深入调查的基础上,分析了洞庭湖区生态环境的主要问题,并提出了治理对策。  相似文献   
925.
The aim of this study is to empirically illustrate the importance of taking movement constraints into account when testing for habitat selection with telemetry data. Global Positioning System relocations of two Scandinavian brown bears were used to compare the results of two different tests of habitat selection by the bears within their home range. Both relied on the comparison of observed dataset with datasets simulated under the hypothesis of random habitat use. The first analysis did not take movement constraints into account (simulations were carried out by randomly distributing a set of points in the home range) whereas the second analysis accounted for these constraints (simulations were carried out by building random trajectories in the home range). The results for the two analyses showed contrasted results. Therefore, not accounting for movement constraints in analyses may result in a misleading biological interpretation. Autocorrelation between relocations is not undesirable: it contains information about ecological processes that should be integrated in habitat selection analyses.  相似文献   
926.
This paper is to show that most discrete models used for population dynamics in ecology are inherently pathological that their predications cannot be independently verified by experiments because they violate a fundamental principle of physics. The result is used to tackle an on-going controversy regarding ecological chaos. Another implication of the result is that all dynamical systems must be modeled by differential equations. As a result it suggests that researches based on discrete modeling must be closely scrutinized and the teaching of calculus and differential equations must be emphasized for students of biology.  相似文献   
927.
Simulations provide an opportunity to examine how single or multiple perturbations may impact a specific species. The objectives of this study were to identify thresholds at which changes in stream peak flow, stream base flow, and/or chytrid fungus presence alter long-term Rana chiricahuensis populations. We used scenarios with varying peak flow mortality rates, base flow mortality rates, and chytrid fungus mortality rates. Sensitivity analysis was also conducted. Over 50 years, populations in six scenarios increased and 13 scenarios decreased. Eight scenarios resulting with fewer than 100 individuals included stochastic effects for at least two of three perturbations and the remaining scenarios included chronic effects of 30% or higher. Scenarios with population increases had either no chytrid fungus effect or chronic effects from perturbations totaling less than 30%. In the absence of chytrid fungus, populations increased and became stable. At a 10% annual death rate caused by chytrid fungus, the R. chiricahuensis population decreased 46.8%. At a 20% death rate, the population decreased 98.6%. Model scenarios were sensitive to peak flow death rates. As peak flow mortality increased to 10 and 20%, extinction rates increased to 91.7 and 99.9%, respectively. With model parameters and the no base flow mortality, R. chiricahuensis populations declined by 92% with a 3.2% extinction rate at 50 years. Models with base flow mortality rates of 10 and 20% resulted in population extinction rates of 48.7 and 96.1%, respectively. Scenario analysis of perturbations on a hypothetical R. chiricahuensis population provided a framework in which to view combined effects on a species. Analysis supports supposition that chytrid fungus is the proximate cause of many amphibian declines, but the added effect of base flow and peak flow has the potential to hasten declines.  相似文献   
928.
Assessing carrying capacities of coastal areas in France   总被引:1,自引:0,他引:1  
This paper provides the methodological framework for carrying capacity assessment through a set of indicators, as implemented in a French case study. The approach aims to help the State and local governments of coastal areas facing population growth and important touristic flows to undergo a local development strategy that does not imperil their territorial strategic resources. This work shows how situations of dysfunction or saturation points have interlinked consequences on environmental, social and economic resources, justifying a crosswise assessment.  相似文献   
929.
It is accepted that the historical routine use of agrochemicals may have resulted in undesirable concentrations of metals in the environment. To investigate and assess the effects of land use on concentrations of heavy metals around the Guanting Reservoir in China, 52 surface soil samples (depth of 2–10 cm) were taken from areas where four types of land use were practiced (including arable land, woodland, bare land, orchard land). The metals and metalloids (As, Cr, Ni, Cu, Zn, Cd, and Pb) were analyzed using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Significant accumulation of As, Cd, and Cr was found in soils of arable land. Based on correlation and cluster analysis, it can be concluded that Cd and Zn originate mainly from phosphate fertilizer, Pb from the use of insecticides, fertilizers, and sewage sludge as well as air deposition, and Cu from copper-based fungicides, while As, Ni and Cr might come from parent soil material. According to an ecological risk analysis of metals based on the ecological index suggested by Hakanson, the four types of land can be ranked by severity of ecological risk as follows: arable land > woodland > bare land > orchard land, with a high ecological risk of Cd for all four types. Management measures for land use planners for avoiding water, soil, and sediment pollution caused by metals around the Guanting Reservoir are presented.  相似文献   
930.
河流生态基流量整合计算模型   总被引:19,自引:2,他引:17  
针对北方地区流域水域生态系统人工化明显和河流断流的现状,提出了河流生态基流量的概念,并分析了其内涵.河流生态基流量包括河道生态基流量、河口生态基流量和湿地生态基流量.河流生态基流量计算应考虑流域内不同水系、不同河段生态环境的差异性和时空变化规律.通过改进生态环境需水量的计算方法,分析河流的空间结构特征、各河段的相互关系以及流域的水特征,提出了整合计算模型.整合计算模型分为2类:不同水系和同一水系的整合.同一水系整合计算模型又分为:河流生态基流量整合模型、河流与湿地生态基流量的整合以及河道生态基流量的整合模型.其中最为复杂的河道生态基流量的整合模型共分为6种形式:简单式、汇流式、分流式、组合式、交叉式和河口式.研究结果表明:各子系统的生态基流量是河流生态基流量整合计算的基础;河流生态基流量保证系数是计算的重要参数,其值在确定基数的基础上,通过恢复模式和空间优化配置这2个影响因子进行调整而得到,取值范围为[0,1];整合计算模型需要明确消耗性生态基流量和非消耗性生态基流量,消耗性生态基流量不受保证系数的影响,非消耗性生态基流量因保证系数取值的不同而变化.  相似文献   
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