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891.
施工承包企业安全成本及其核算的研究   总被引:4,自引:0,他引:4  
依据施工承包企业安全管理的目标、特点和程序,提出安全成本的概念和构成以及保证性安全成本对损失性安全成本的直接影响.同时,借助施工安全成本与安全度的关系、提高安全技术工作的经济合理性、加速构建施工承包企业安全成本核算制度,优化施工承包企业的安全管理工作,并为提高企业经济效益及社会经济运行的安全度奠定基础.  相似文献   
892.
ABSTRACT

Nepal is in the process of formulating its forest policies at the provincial level . Various community-managed forests have been designed in the past by the Nepal government to decentralize the forest for its sustainable management practice. This study facilitates the process of identifying appropriate forest management options in two of the provinces, namely Provinces Three and Gandaki. Four forest management options – passive, active, scientific and multiple – were identified following the existing management practices. For the evaluation of the overall performance of the options, a framework with three criteria, 10 indicators and 28 verifiers were designed. The framework followed the green economy perspective considering the improvement of the forest conditions, economic and social well-being, and low carbon emission. The Analytical Hierarchy Process was used to prioritize the best management option and analyse trade-offs to guide future decision-making and reduce the risk of unwanted consequences. Our results show that the elicitation of preferences for the evaluation criteria varied by stakeholder groups. Their preference was largely guided by improving the forest resource condition and economic well-being. Foresters prefer scientific and active forest management, policymakers prefer multiple-use forest management and scientific management, whereas community forest user groups prefer active forest management. We argue that a scientific management approach may contribute better to economic aspects, although it may often compromise the other aspects. The multiple forest management option seems to be the best for green economy considering ecological, economic and social consequences.  相似文献   
893.
Economic and Ecological Outcomes of Flexible Biodiversity Offset Systems   总被引:1,自引:0,他引:1  
The commonly expressed goal of biodiversity offsets is to achieve no net loss of specific biological features affected by development. However, strict equivalency requirements may complicate trading of offset credits, increase costs due to restricted offset placement options, and force offset activities to focus on features that may not represent regional conservation priorities. Using the oil sands industry of Alberta, Canada, as a case study, we evaluated the economic and ecological performance of alternative offset systems targeting either ecologically equivalent areas (vegetation types) or regional conservation priorities (caribou and the Dry Mixedwood natural subregion). Exchanging dissimilar biodiversity elements requires assessment via a generalized metric; we used an empirically derived index of biodiversity intactness to link offsets with losses incurred by development. We considered 2 offset activities: land protection, with costs estimated as the net present value of profits of petroleum and timber resources to be paid as compensation to resource tenure holders, and restoration of anthropogenic footprint, with costs estimated from existing restoration projects. We used the spatial optimization tool MARXAN to develop hypothetical offset networks that met either the equivalent‐vegetation or conservation‐priority targets. Networks that required offsetting equivalent vegetation cost 2–17 times more than priority‐focused networks. This finding calls into question the prudence of equivalency‐based systems, particularly in relatively undeveloped jurisdictions, where conservation focuses on limiting and directing future losses. Priority‐focused offsets may offer benefits to industry and environmental stakeholders by allowing for lower‐cost conservation of valued ecological features and may invite discussion on what land‐use trade‐offs are acceptable when trading biodiversity via offsets. Resultados Económicos y Ecológicos de Sistemas de Compensación de Biodiversidad Flexible Habib et al.  相似文献   
894.
生态补偿过程动态演化机制及其稳定策略研究   总被引:1,自引:1,他引:0  
生态补偿是通过调节相关方的利益关系,实现可持续利用生态系统服务的一种手段或制度安排。论文从微观维度对生态补偿问题进行研究,将生态补偿利益群体分为实施群和受益群,建立非对称演化博弈模型,分析各群体利益关系的复制动态、演化稳定策略和演化博弈系统的稳定性。结果表明:在"举报惩罚"制度存在的情况下,两群体间的演化博弈存在唯一的稳定均衡策略(保护、补偿),即实施群选择"保护"策略,受益群选择"补偿"策略,其中实施群决策主导系统稳定性;利益群体各决策选择的比重是稳定均衡策略的重要影响因素,增加实施群和受益群选择"保护"和"补偿"策略的比重,可加快稳定均衡策略的有效形成。  相似文献   
895.
论文选取2000、2006年时相相近的TM遥感影像作为山东黄河流域的基本数据源,采用监督分类法、专家分类法进行森林资源的分类和验证,运用层次分析和模糊数学法建立森林资源生态适宜性综合评价模型。结果表明,流域的森林资源分布极不均匀,济南、泰安、莱芜的森林覆盖率超过30%,其它地市只有15%。森林资源生态适宜性方面,泰安市优,济南市和莱芜市良,淄博市、滨州市、菏泽市、东营市和德州市中等,济宁市和聊城市较差。6 a间,泰安市的森林资源生态适宜性评价由良好到优秀,济南市和莱芜市的评价得分值虽然都较高,但是,济南市朝好的方向发展,相反,莱芜市的得分值不升反降。淄博市、滨州市、菏泽市、东营市和德州市的得分值虽然没有达到良好标准,但其变好的趋势非常明显,济宁市和聊城市相对较差。  相似文献   
896.
Behavioural models for both humans and other animals often assume economic rationality on the part of decision makers. Economic rationality supposes that outcomes can be assigned objective values within a stable valuation framework and that choices are made to maximise a decision maker’s expected payoff. Yet, both human and animal behaviour is often not economically rational. Here, we compare economically rational making strategies with a strategy (trade-off contrasts) that has been proposed to account for decision-making behaviour in humans that departs of axiomatic rationality. We model the fitness of these strategies in a simple environment where choices are made on repeated occasions, there is stochastic fluctuation in the choices available at any given time, and uncertainty about what choices will be available in the future. Our results show that, for at least some of the model parameter space, non-rational decision strategies achieve higher fitness than economically rational strategies. The differences were comparable in magnitude to selection differentials observed in nature.  相似文献   
897.
Vanadium (V) is widely used industrially, and plays an important role in the biosphere. Sensitive and reliable analytical methods to determine V in various kinds of samples are of extensive interest. Mainly two spectrophotometric methods developed in the last decade are discussed, namely complex formation methods and catalytic methods. The former is based on either oxidation or reduction of V leading to coloured complexes with proper reagents; they are applicable to determination of V at the mg L?1 level. Catalytic methods are based on the ability of V to catalyse the oxidation of various organic dyes and are applicable to determination at the μg L?1 level. Both methods are used for determination of V in environmental and biological samples.  相似文献   
898.
Organizations are increasingly engaging in socially and environmentally sustainable initiatives. This paper focuses on the institutional isomorphism mechanisms to analyse the organizational adoption of sustainable manufacturing practices like eco-design, source reduction, and environmental management practices. This paper empirically examines the role of institutional influence in the organizational adoption of sustainable manufacturing practices among firms in India. The results of this study confirm the significance of the three institutional isomorphism mechanisms in influencing sustainable responses, but not all mechanisms influence the organizational response equally. In particular, the results show a strong influence of self-regulatory normative isomorphism on the implementation.  相似文献   
899.
月湖近代生物硅沉积测定与营养演化的动态过程   总被引:4,自引:2,他引:2  
在综合了国内外实验方法基础上,完善了湖泊沉积生物硅实验室测定方法.利用此方法,首次对一富营养化小型浅水湖泊--武汉市汉阳区月湖进行了2个柱状沉积物的生物硅含量测试.结果表明,生物硅可以反映月湖的营养演化的动态过程,130 a前,湖泊受到的环境压力为轻;20世纪初期,月湖生物硅沉积缓慢上升,为水体富营养化开始发生时间;20世纪30年代至50年代,月湖已成为一富营养化湖泊;20世纪60年代至80年代,月湖水质持续恶化;20世纪80年代至月湖清淤前这段时期入湖污水增多,这加速了生物硅的沉积,正是这段时期使月湖最终沦为劣五类水质的湖泊.  相似文献   
900.
刘玉  冯健 《自然资源学报》2008,23(3):545-552
目前,我国跨区资源调配工程双方的区域利益关系尚未完全理顺,区域利益矛盾存在并有进一步激化的可能。西电东送南通道双方在价格水平与增长趋势、送电曲线和生态补偿等方面存在较大分歧,当前的资源交易与区域利益分配模式存在不合理的因素。西电东送的特殊性需要由市场和政府共同承担协调区域利益关系的任务,市场化是西电东送的必然取向,但政府应在体现西电东送综合效益、潜在效益和隐性效益及促进区域协调发展等方面发挥作用。  相似文献   
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