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101.
ABSTRACT: Rapid population growth in the metropolitan area of Denver, Colorado, is causing conflicts over water use. Two cities, Thomton and Westminster, have begun condemnation proceedings against three irrigation companies to secure agricultural water rights for municipal use. This is the first condemnation proceeding against irrigation water rights for municipal use. Should the suit succeed, over 30,000 acres of presently irrigated land will lose its water supply. There are about four hundred landowners in the area; two hundred of these are commercial farmers, including truck, dairy and specialty farms. Total agricultural production amounts to about $8 million per year. About 561 jobs related to agriculture will disappear along with about $4 million in not income. Only 6.4 percent of the farmland along the Front Range is irrigated. Continued urban growth will put pressure on the water supply of much of this land. The interested parties of the region should cooperate to lessen the impact of urban growth on agricultural lands and water by forming a metropolitan water district. Such a district could share costs of development of additional municipal water and develop systems where municipalities would recycle waste water back to the irrigated lands.  相似文献   
102.
    
Many of the world's rangelands are degraded due to either natural or anthropogenic causes. One of the main indicators of the degradation process is the depletion of the organic carbon stocks in the soil. The organic carbon plays a crucial role in supporting the soil microbial community, maintaining the soil structure formation and stability, and retaining water and nutrients in the uppermost soil layers. Biochar, the by-product of the pyrolysis technology for bio-energy production, has been proven to have the capability to efficiently maintain soil quality and increase vegetative production. At the same time, the inert nature of the biochar enables the long-term sequestration of carbon in soil. To date, the application of biochar has been examined almost exclusively in arable lands, but not yet in rangelands. The objective of this paper is to raise awareness of this topic in order to encourage research and development in this field. Progress in knowledge and understanding on this matter could contribute to the reclamation of degraded rangelands. At the same time, it would potentially increase their capacity for long-term sequestration of carbon to a rate of between 0.69 and 10.7 Pg. Large-scale implementation of this practice in the future should be funded through central authorities, based on payments for improvement in ecosystem services.  相似文献   
103.
Global climate change measures are difficult to implement. In this context, local air pollution measures may play an important role in the political agenda since their effects are felt more immediately by citizens. Distributional implications are one of the main barriers for implementing environmental policies. This paper explores the distributional implications of air pollution taxes and compares them to climate change taxes. For the comparison, both tax schemes were set to yield the same revenue. Methodologically, the study uses a top–down approach linking a macro model to a micro model. We find that taxes on local air pollutants are more regressive than those levied on CO2. This is because the goods implicitly taxed have a greater weight in the consumer basket of low-income groups, even if the tax revenues are recycled. Furthermore, the revenue-neutral recycle scheme increases both taxes efficiency, but, at the same time, can increase regressivity.  相似文献   
104.
    
Voluntary, permanent land protection is a key conservation process in many countries. Concerns with the effectiveness of such decentralized processes exist due to the potential for (1) selection bias, that is, the protection of parcels whose land cover would have been conserved in the absence of protection, and (2) local spillover effects, that is, protection increasing the likelihood that adjacent parcels lose land cover due to additional conversion. We examine the validity of both concerns using a quasi-experimental approach and a dataset of 220,187 parcels and 26 years of protection and land-cover change in Massachusetts. We find that land acquisitions and conservation restrictions implemented by state, local, and nongovernmental actors reduced forest loss and conversion to developed uses without increasing either type of land-cover change on adjacent parcels. Our results suggest that voluntary, permanent land protection can make significant contributions in protecting land cover in landscapes dominated by private ownership.  相似文献   
105.
    
Social innovation represents a social practice that aims to meet social needs by involving communities in dialogues through participatory and collaborative approaches. One new and particular solution of social innovation is represented by Urban Civic Networks. However, considering the novelty of this topic, neither the benefits nor the role of public entities in implementing such practice of social innovation, nor the strengths of the implementation process are known, yet. This study aims to fill this gap through the analysis of a single‐case study, based upon theories of social innovation and social change, referring to the City of Bari. Results show that implementation of Urban Civic Networks generates both tangible and intangible benefits and demonstrate that local government plays a pivotal and leading role in the implementation process. Finally, they show that the strengths of this practice are connected to bottom‐up approaches enabling efficient knowledge management and collaboration.  相似文献   
106.
Recent legislation to initiate vegetation management in the Central Sierra hydrologic region of California includes a focus on corresponding changes in water yield. This served as the impetus for developing a combined geographic information system (GIS) and simulation assessment framework. Using the existing vegetation density condition, together with proposed rules for thinning to reduce fire risk, a set of simulation model inputs were generated for examining the impact of the thinning scenario on water yield. The approach allows results to be expressed as the mean and standard deviation of change in water yield for each 1-km2 map cell that is thinned. Values for groups of cells are aggregated for typical watershed units using area-weighted averaging. Wet, dry, and average precipitation years were simulated over a large region. Where snow plays an important role in hydrologic processes, the simulated change in water yield was less than 0.5% of expected annual runoff for a typical watershed. Such small changes would be undetectable in the field using conventional stream flow analysis. These results suggest that use of water yield increases to help justify forest-thinning activities or offset their cost will be difficult.  相似文献   
107.
为了解近年南海明珠项目、葫芦岛、秀英港扩建工程等人工填海工程对海口湾冲淤变化的影响,基于FVCOM海洋数值模型,对研究区人工填海前后潮流场、波浪场及冲淤变化进行了数值模拟。人工填海后,综合各条件下的冲淤情况,海口湾受潮流和波浪共同作用大部分区域处于淤积状态,年淤积量预测值为0.1~1.0 m;白沙角等局部区域处于侵蚀状态,年冲刷量预测值为0.1~0.3 m;受海口湾人工填海工程的影响,秀英港航道的水动力条件减弱,对通航条件改善有利,需加强航道的水深监测和定时的清淤工作;在南海明珠人工岛南侧波影区泥沙堆积会形成向海的舌状的突出体,其两侧海岸形成侵蚀后退带,需人工补沙等措施以保证岸线稳定。  相似文献   
108.
This experimental research addresses the effectiveness of communication about complex environmental issues, depending on whether the same information is provided by multiple collaborating or by individual organizations (i.e., stakeholders). The information provided pertains to carbon dioxide capture and storage (CCS) technology, as an example of a complex environmental issue. In Studies 1 (N = 75) and 2 (N = 66) we found that participants perceived factual information from collaborating stakeholders to be of higher quality than when the same information was provided by individual stakeholders. As predicted, the expectation of diverse perspectives being represented in the collaborative information mediated this effect. In addition, in Study 3 (N = 79) the perceived dissimilarity of collaborating stakeholders was shown to be an important precondition for the collaboration effect observed in Studies 1 and 2. Finally, these studies indicate that occasional collaboration between different stakeholders does not necessarily harm the perceived credibility of each individual stakeholder.  相似文献   
109.
吐曼河近5a水质变化浅析   总被引:1,自引:0,他引:1  
通过单因子评价法对吐曼河水质现状及近期变化趋势进行了分析,揭示了近几年来吐曼河水质年内及年际变化的特点,以期对吐曼河水污染治理提供参考。  相似文献   
110.
    
Building on conservation of resources theory, we construct a dual-pathway approach which aims to reveal the mixed effects of organizational resilience on environmental, social and corporate governance (ESG) performance. Specifically, this paper argues that organizational resilience will both stimulate innovation input, enhancing ESG performance (positive pathway) and promote strategic change, inhibiting ESG performance (negative pathway). Meanwhile, the indirect effect of organizational resilience on ESG performance via innovation input and strategic change is also moderated by industry concentration, and both indirect effects are stronger when industry concentration is low. Data of Chinese A-share listed firms from 2010 to 2020 support the proposed theoretical framework. This study provides theoretical and managerial implications for organizational resilience research.  相似文献   
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