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111.
Tropospheric ozone (O3) pollution is increasing in the Beijing-Tianjin-Hebei (BTH) region despite a significant decline in atmospheric fine aerosol particles (PM2.5) in recent years. However, the intrinsic reason for the elevation of the regional O3 is still unclear. In this study, we analyzed the spatio-temporal variations of tropospheric O3 and relevant pollutants (PM2.5, NO2, and CO) in the BTH region based on monitoring data from the China Ministry of Ecology and Environment during the period of 2014–2019. The results showed that summertime O3 concentrations were constant in Beijing (BJ, 0.06 µg/(m3•year)) but increased significantly in Tianjin (TJ, 9.09 µg/(m3•year)) and Hebei (HB, 6.06 µg/(m3•year)). Distinct O3 trends between Beijing and other cities in BTH could not be attributed to the significant decrease in PM2.5 (from -5.08 to -6.32 µg/(m3•year)) and CO (from -0.053 to -0.090 mg/(m3•year)) because their decreasing rates were approximately the same in all the cities. The relatively stable O3 concentrations during the investigating period in BJ may be attributed to a faster decreasing rate of NO2 (BJ: -2.55 µg/(m3•year); TJ: -1.16 µg/(m3•year); HB: -1.34 µg/(m3•year)), indicating that the continued reduction of NOx will be an effective mitigation strategy for reducing regional O3 pollution. Significant positive correlations were found between daily maximum 8 hr average (MDA8) O3 concentrations and vehicle population and highway freight transportation in HB. Therefore, we speculate that the increase in rural NOx emissions due to the increase in vehicle emissions in the vast rural areas around HB greatly accelerates regional O3 formation, accounting for the significant increasing trends of O3 in HB.  相似文献   
112.
SUMMARY

The Rio Earth Summit and publication and distribution of Agenda 21 (UN, 1992) have generated much activity in many nations towards development and implementation of community indicators of sustainable development (SI). In recent years efforts at development and implementation of SI have intensified at regional and urban government levels, although fewer efforts are evident at a rural community level. In response to initial ad hoc efforts, methodologies for SI construction are currently being proposed, tested and refined. Within this evolutionary process, increasing recognition is being given to the critical need for, and importance of, ‘stakeholder’ involvement in SI development and implementation. This paper critically reviews these and related efforts from the perspective of rural communities in Canada. The argument is presented that the process of development and implementation of rural community-level SI can significantly benefit from development and implementation of a methodological approach in support of principles and practices of effective stakeholder involvement. It is further argued that development of SI must be stakeholder-driven, and that a pivotal element in the SI development process is the facilitation of information sharing. The paper concludes with a proposal for an approach to stakeholder participation and information sharing achieved through research, testing and refinement, and integration of these concepts within the process of rural community sustainable indicator development.  相似文献   
113.
Increased efforts to analyze the human dimensions of anglers are necessary to improve freshwater fisheries management. This paper is a comparative analysis of urban and rural anglers living in a metropolis, based on n = 1061 anglers responding to a mail survey in the German capital of Berlin. More than two thirds of the anglers (71%) had spent most (>50%) of their effort outside the city borders of Berlin and thus were categorized as rural anglers. Compared to the rural anglers, urban anglers (50% of total effort spent inside the city) were younger and less educated. Urban anglers were more avid and committed, less mobile, and more frequently fished from boats and during weekdays. Rural anglers were more experienced, fished for longer times per trip, fished more often at weekends and on holidays, were more often members of angling clubs, and more frequently caught higher valued fish species. The achievement and fish quantity aspects of the angling experience were more important for urban than for rural anglers. Concerning management options, urban anglers more frequently suggested constraining other stakeholders and reducing regulations, whereas rural anglers more often proposed improving physical access to angling sites. Future urban fishing programs should offer ease of access, connection to public transportation, moderate prices, and diverse piscivorous fish stocks. In contrast to rural fisheries, the provision of high ecological and aesthetical quality of the angling waters can be regarded as of minor importance in urban fisheries. Rural fisheries managers need to consider the needs of stakeholders living in Berlin to minimize impacts on the less degraded rural water bodies and potential user conflicts with resident anglers. Ecosystem-based management approaches should guide rural fisheries policy.  相似文献   
114.
The interrelationship of society and environment is addressed here through the study of a remote fishing village of 750 people. An interdisciplinary study evaluated demographic, economic, and social aspects of the community, and simulation modeling was used to integrate these societal characteristics with environmental factors.The population of the village had grown gradually until the 1960's, when a decline began. Out-migration correlated with declining fish harvests and with increased communications with urban centers. Fishing had provided the greatest economic opportunity, followed by logging. A survey was conducted to investigate the costs and revenues of village fishermen. Diversification characterized the local fleet, and analysis showed that rates of return on investment in the current year were equal between vessel types.The variable levels and rate parameters of the demographic, economic, and social components of the model were specified through static and time series data. Sensitivity analysis to assess the effects of uncertainty, and validation tests against known historical changes were also conducted. Forecast scenarios identified the development options under several levels of fish abundance and investment. The weight given to ecological versus economic resource management registered disproportionate effects due to the interaction between investment and migration rates and resource stochasticity. This finding argues against a golden mean rule for evaluating policy trade-offs and argues for the importance of using a dynamic, socio-ecological perspective in designing development policies for rural communities.  相似文献   
115.
The Countryside Commission's report A Better Future for the Uplands puts forward a new strategy for public intervention in the uplands of England and Wales. The aim of the report is to integrate rural policies and to promote higher environmental priorities in rural areas. This paper considers the degree to which the report is successful in planning to achieve these ends. The paper is specifically concerned with the planning methodology on which the report is based. The paper argues for an approach to rural planning which permits the consideration of more radical solutions to rural problems, along with the application of a more systematic planning methodology, in order to assist in the choice of an appropriate direction for planned change.  相似文献   
116.
Financing of wasteland afforestation in India   总被引:2,自引:0,他引:2  
India has vast tracts of wastelands, which have been lying barren for ages. Most such lands are physically suitable for growing trees and thus could be put to socially productive uses. However, although usually economically viable, afforestation requires massive initial investment, generally beyond the means of the landowners. Also, government budgetary allocations do not cover current needs. In this situation, institutional credit is required. The National Bank for Agriculture and Rural Development (NABARD) of India has recognized this need and has devised a number of different schemes to provide refinance facilities to individuals and organisations. Although the number of forestry schemes refinanced by NABARD has increased rapidly in the past, they currently constitute only about 1% of the total number of loans sanctioned, and only about 2% of NABARD's cumulative loan disbursement to date. In fact, since 1992, the share of afforestation schemes has declined. A number of factors have been identified as major constraints, including time-consuming and complicated procedures for accessing land; restrictions on harvesting and selling trees; delays in sanctioning and disbursement of bank credit; non-remunerative prices for tree products; and flawed public policies and programmes. This article argues that unless these constraints are overcome, NABARD will not be able to play an effective role in speeding up development programmes in the forestry sector. It further argues that most of the current constraints on institutional credit for wasteland afforestation can be removed or relaxed. Practical strategies are suggested to mobilize more funds and channel more institutional credit for wasteland afforestation in India.  相似文献   
117.
This article examines a number of issues connected with the development of small-scale hydroelectric power and related investments in Nepal. The micro-hydro investment scheme in Barpak village serves as a case study, and the article also presents a number of related issues discussed against the background of the evolution of micro-hydro power in Nepal. The article outlines the success of micro-hydro development, modest in relation to its enormous potential, the realization of which depends on whether a number of challenges and constraints can be overcome. The article closes with suggestions on implementing sustainable micro-hydro development in rural areas, based on the Barpak experience and the authors' other recent studies of rural energy issues in Nepal.  相似文献   
118.
This paper considers the contribution of computing to the implementation of a policy of partnership between public environmental agencies and local voluntary groups. The present policy commitment to partnerships of this kind is reviewed. Particular information needs arise when public agencies seek to give co‐ordinated support to the environmental action undertaken by local groups. These stem from the disaggregated nature of the structure and functions of the voluntary sector. Computer‐based information systems are identified as a bridge between the regional organisation of public agencies and the local activities of voluntary groups. A computer system devised to aid the forward planning of public support for voluntary action is described. It is considered that this technique has value as part of a wider strategy of interaction between the public and voluntary sectors.  相似文献   
119.
Whether the proposed Yucca Mountain nuclear waste repository system will adversely impact tourism in southern Nevada is an open question of particular importance to visitor-oriented rural counties bisected by planned waste transportatin corridors (highway or rail). As part of one such county's repository impact assessment program, tourism implications of Three Mile Island (TMI) and other major hazard events have beem revisited to inform ongoing county-wide socioeconomic assessments and contingency planning efforts. This paper summarizes key research implications of such research as applied to Lincoln County, Nevada. Implications for other rural counties are discussed in light of the research findings.  相似文献   
120.
鞠菲 《环境保护科学》2015,41(2):73-76,121
为了研究锦州市农村饮用水水源地基础环境状况综合评估工作,从环境禀赋、污染状况、环境监管和环境风险四个领域入手,分析农村饮用水水源地存在的主要环境问题和原因。有以下几点:水文地质参数匮乏,上游来水水质较差;由于地质因素及当地人民生活、牲畜饲养所排废物以及长期施用化肥导致总硬度及高锰酸盐指数超标;基本没有开展保护区的划分,也没有进行勘界、树立水源保护区标志、污染源搬迁等工作。  相似文献   
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