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171.
文章运用人工神经网络方法,选取了8个经济指标,以黑龙江省2004年统计年鉴为数据源,对年黑龙江省66个县(市)的社会经济发展水平进行评价。结果表明:黑龙江省县域经济整体发展水平不高,而且区域差异显著;根据评价结果利用聚类分析方法将黑龙江省县域经济发展水平分为5级。文章最后提出了促进县域经济发展的措施。  相似文献   
172.
水土保持生态补偿对于我国的水土流失治理意义重大,水土保持补偿标准的确定是建立生态补偿机制的核心问题。基于潘家口水库上游东北沟流域1990年和2009年土地利用数据和气候、 土壤、 植被、 DEM及农户调查等数据,应用通用土壤侵蚀方程模型(RUSLE)计算该流域采取预防水土流失措施后的土壤侵蚀减少量,在此基础上采用环境经济学的方法核算水土保持生态功能的提供方和受益方两个主体的成本和收益,并构建了水土保持生态补偿标准计算模型,实现了水土保持生态补偿标准定量计算。结果显示:流域生态系统的年土壤保持量为6.49×104 t·a-1;水土保持服务提供方损失为24.48×104元,所得收益来自减少土地损失和肥力损失的价值共计44.21×104元;水土保持服务受益方主要指下游潘家口水库所得收益来自减少泥沙淤积和减少富营养化共计84.88×104元;流域所得的补偿介于24.48×104元(222.55元/人)到46.90×104元(426.36元/人)之间。  相似文献   
173.
The new WIOD database allows for improved empirical analysis on a wide range of important environmental research questions.In this paper we demonstrate the scientific power of the WIOD database and analyze very urgent policy questions on the impacts of international trade and structural change on the environment.We apply recent econometric approaches to show the impact of international trade on the environment via its different channels as for instance to increase welfare and potentially affect environmental regulation as well as countries’sector.This approach has become known as the econometric structural decomposition method.In addition to these guidelines by the literature,an econometric panel data approach is offered to shed some light on the impact of structural change and international trade on environmental pressure,where we especially address and solve several endogeneity issues that add further complexity to the analysis.  相似文献   
174.
The control of water pollution in China's South-North Water Transfer Project (SNWTP) is examined through the lens of promotion tournaments as Chinese governmentality to offer a special perspective on China's hydro-politics and Chinese manners of water pollution control. This paper characterizes the existing form of governmentality in the SNWTP, pointing to its problems and potential resolutions. The promotion tournament is a market system with authoritarian control, designed to reconcile the incentives of local officials and the central managers of the SNWTP. This governmentality embodies characteristics of China's authoritarian water management system: centralized personnel control combined with market-oriented promotion competitions. However, a clear conflict between the requirements of ecological modernization and the use of power in China's water management system leads to distorted behaviors among local officials, an important source of problems in China's water management system. Compared to promotion tournaments, payments for ecosystem services or eco-compensation are applications of neoliberal environmentalism that could overcome the shortcomings of tournaments, and become the most critical governmentality for water pollution control in the SNWTP.  相似文献   
175.
为分析非农就业对农户种植多样性的影响,通过农户问卷调查手段获得356份农户问卷,以在江苏省泰兴市和宿豫区的农户问卷调查数据为基础,采用Poisson回归方法,估计了农户种植多样性决策模型。依据模型估计结果,分析了非农就业对农户种植多样性的影响。分析表明,农户的种植多样性受到多种因素的影响。负责农业生产家庭成员受教育年限提高1 a,种植多样性提高1.5%左右;种植面积增加1 hm2,则农户种植多样性提高28%左右;就农户参与非农活动的影响而言,与负责农业生产家庭成员不参与非农活动的农户相比较,负责农业生产家庭成员参与非农活动家庭的种植多样性减少11%左右;负责农业生产家庭成员参与非农活动月数增加1个月,农户种植多样性大约降低1.4%。分析说明负责农业生产家庭成员参与非农就业会显著降低农户种植多样性。  相似文献   
176.
SUMMARY

Long-term cropland fallowing decisions of farmers in the West Nile Province of Uganda were studied. Tabular and regression methods are used to examine the relationship between farm and household factors and seasons of net fallowing. The results show that farmers plan to decrease the rate of fallowing in the immediate future. Serious (but undocumented) problems in maintaining cropland productivity could result. Population density had a large and negative effect on net fallowing (seasons of fallowing less seasons of crops), decreasing from the current average of ?0.6 seasons to ?2.21 seasons for a doubling of population. This 268% decrease in the use of fallowing could occur in as few as 13.5 years, assuming a 3% annual population growth rate. Farms larger in size, but with no increase in per capita cropland availability, had a higher rate of net fallowing. Cashcrop production was negatively associated with net fallowing, whilst farmer age had a positive association.

The results have implications for both agricultural policy and guidance for further research on cropland fallowing. Increased cash-cropping should not be recommended unless the full economic costs of using land resources are evaluated. Much of the increased area for cash-crop production would come from fallowed land, decreasing the rate of fallowing and thus increasing the potential for soil degradation. Fallowing has long been used in the area to maintain cropland productivity. Building upon farmers current practices and improving fallowing through the use of green manures and agroforestry could prove to be more economical than the use of mineral fertilizers. Investigating why farms larger in size and those with older head-of-households were able to use fallowing more effectively may provide key information for the development of more productive fallowing technologies.  相似文献   
177.
In this paper, I show the existence and the characteristics of equilibrium in a non-renewable resource market where extraction costs are non-convex and market price is subject to stochastic shocks, an empirically relevant setting. In my model firms may be motivated to hold inventories to facilitate production smoothing, which allows them to continue producing at a smooth pace at any instant when extraction ceases, e.g. when reserves are exhausted. This aspect of the model then supports a competitive equilibrium in the presence of non-convex costs. Casual empirical evidence is provided that supports the central features of my model for a variety of non-renewable resources, lending credence to the explanation for equilibrium I propose.  相似文献   
178.
David A. Savage 《Disasters》2019,43(4):771-798
This paper outlines why a move towards a complex adaptive systems model of behaviour is required if the goal is to generate better understanding of how individuals and groups interact with their environment in a disaster setting. To accomplish this objective, a bridge must be built between the broader social sciences and behavioural economics to incorporate discipline‐specific insights that are needed to move towards complexity. This is only possible through a deeper understanding of behaviour and how the environment in which they occur can influence actions. It is then that one can counteract the poor behavioural predictions, flawed policies based on myth, inefficient design, and suboptimal outcomes that have flourished in the absence of a complex adaptive systems model. This paper provides a conceptual framework that draws on concepts from across the natural and social sciences, such as behavioural economics, endocrinology, psychology, sociobiology, and sociology in order to build an interactive theory of disaster behaviour.  相似文献   
179.
纯氧曝气在城市污水处理中的经济性比较   总被引:3,自引:0,他引:3  
就城市污水处理工艺中鼓风曝气系统和纯氧(或富氧)曝气系统,从原理、技术性指标等方面进行了分析和比较,显然纯氧曝气系统比鼓风曝气系统具有一定的优越性。在城市污水处理厂老厂改造和新厂建设中采用纯氧曝气法具有良好的前景。  相似文献   
180.
• Economics of food waste treatment projects at 29 pilot cities in China was examined. • Roles of location, population size, processing technique, and income were studied. • Economic benefits were limited with a profit to cost ratio of 0.08±0.37. • Service population size affects construction economics significantly (P = 0.016). • Choice of food waste processing technique affects operating economics notably. This study examines the economic benefits of food waste treatment projects in China and factors affecting them. National-level pilot projects for food waste treatment located in 29 cities were selected as samples. The economics of food waste recycling from the investors’ perspective, in terms of investment during the construction phase and cost and benefit during the operation phase, was assessed. Results indicate that the average tonnage investment of food waste treatment projects was RMB 700.0±188.9 thousand yuan, with a profit to cost ratio of 0.08±0.37. This ratio increased to 0.95±0.57 following the application of government subsidies. It highlights the limited economic benefits of food waste treatment facilities, which rely on government subsidies to maintain their operations in China. Further analysis using a multi-factor analysis model revealed that regional location, service population size, processing techniques, and urban income exerted varying impacts on the economy of food waste treatment. Population size exerted the highest impact (P = 0.016) during the construction stage, and processing techniques notably influenced the project economy during the operation stage. The study highlights the need to prioritize service population size and processing techniques during economic decision-making and management of food waste recycling projects. The results of this study can serve as a valuable practical reference for guiding future policies regarding food waste treatment and related planning.  相似文献   
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