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291.
In the last decade, Indian shrimp aquaculture production tripled from 30,000 tons (1990) to 102,000 tons (1999). This fast development, combined with a lack of adequate planning and regulation, caused a number of environmental problems and social conflicts, including conversion of mangroves, water pollution, and salinization of drinking water wells. Because of the significant investments made in shrimp culture and the size of the environmental and social impacts, the formulation of a regulatory framework for shrimp aquaculture has been subject to an intensive debate between the aquaculture and the environmental lobbies. Following an order from the Supreme Court (1996), the Aquaculture Authority was established and a regulatory and institutional framework for the shrimp aquaculture sector has been set up. However, implementation of the system is still defective, and there is an urgent need for improvement. Farmers are increasingly able to prevent the devastating white spot disease in shrimps, and in the absence of proper planning and regulation, further expansion of shrimp production could result in significant additional environmental and social costs. The environmental and social management of Indian shrimp farming can be improved through a mix of policy measures, including strengthening of the license system, more effective enforcement of regulations, the use of economic incentives, and increased monitoring of environmental and social impacts.  相似文献   
292.
We studied trends in food production and nitrous oxide emissions from India's agricultural sector between 1961 and 2000. Data from Food and Agricultural Statistics (FAO) have been gathered covering production, consumption, fertilizer use and livestock details. IPCC 1996 revised guidelines were followed in studying the variations in N2O-N emissions. Results suggest that total N2O-N emissions (direct, animal waste and indirect sources) increased ~6.1 times from ~0.048 to ~0.294 Tg N2O-N, over 40 years. Source-wise breakdown of emissions from 1961–2000 indicated that during 1961 most of the N2O-N inputs were from crop residues (61%) and biological nitrogen fixation (25%), while during 2000 the main sources were synthetic fertilizer (~48%) and crop residues (19%). Direct emissions increased from ~0.031 to ~0.183 Tg. It is estimated that ~3.1% of global N2O-N emissions comes from India. Trends in food production, primarily cereals (rice, wheat and coarse grains) and pulses, and fertilizer consumption from 1961–2000 suggest that food production (cereals and pulses) increased only 3.7 times, while nitrogenous fertilizer consumption increased ~43 times over this period, leading to extensive release of nitrogen to the atmosphere. From this study, we infer that the challenge for Indian agriculture lies not only in increasing production but also in achieving production stability while minimizing the impact to the environment, through various management and mitigation options.  相似文献   
293.
Sustainable management of Electronic waste (E-waste) is a major challenge for contemporary India, an emerging economy burdened with both the domestic generation and illegal import of E-waste. Considering the ever-increasing complexities of E-waste in Indian cities, this paper aims to evaluate the current trends, opportunities and challenges associated with consumption of electronic items (with respect to computers and mobile phones) and disposal of E-waste in urban India. Bangalore, a city popularly known as the ‘Silicon Valley of India’, is considered as a case study in order to evaluate public awareness, household consumption and E-waste disposal behaviours. The city profile of Bangalore indicates that it has a rapidly emerging market for electronics and thus, has the potential to act as a ‘model’ for evaluating the issues concerning E-waste in metropolitan India. Questionnaires were distributed originally among 300 households with an effective response rate of 63.3%. The results indicate that the majority of households (59.3%) still retain their obsolete electronics due to lack of knowledge about proper E-waste management. High awareness about E-waste and high willingness to recycle/repair their E-waste (above 80% in both cases) are yet to be translated into responsible disposal/recycling behaviour as 95.8% of households have no knowledge about the presence of any formal recycling centre. Income, education, age and gender dimensions associated with E-waste disposal behaviour and awareness were also evaluated. Although we found no gender differences for most of the parameters, there have been some interesting correlations in age and income-wise segregation of disposal behaviour. We noted that the city of Bangalore still possesses some typical Indian socio-cultural characteristics, such as considering E-waste as ‘valuables’, changing several hands before final disposal, defying ‘brand’ or ‘looks’ consciousness, etc., which could be directed towards responsible E-waste disposal behaviours. We suggest that establishing appropriate and convenient E-waste collection/recycling facilities, ensuring responsible household disposal behaviour, implementing effective laws and legislation, and organizing mass E-waste awareness campaigns would aid in addressing the current E-waste concerns in the city.  相似文献   
294.
1960-2011 年东北地区热量资源时空变化特征   总被引:3,自引:1,他引:2  
基于1961-2011 年东北地区88 个气象站逐日气温资料,采用Kendall-Theil 线性趋势估计等方法探讨了该地区热量资源的时空变化特征。结果表明,近50 多年东北地区稳定≥0 ℃积温以25~95 ℃·d/10 a 的趋势显著增加,三江平原的增加趋势明显大于东部山区。稳定≥0 ℃气温的起始期在东北北部和中部显著提前,终止期在北部基本显著延后,日平均气温稳定≥0℃的日数在北部和中部地区基本以2~4 d/10 a 的趋势显著增加。东北地区大部分站点终霜冻日期明显提前,初霜冻日期明显延后,无霜冻期基本以3~5 d/10 a 的趋势显著增加。稳定≥10 ℃积温以30~110 ℃·d/10 a 的趋势显著增加,稳定≥10 ℃气温的起始期北部地区显著提前,终止期南部地区显著延后,作物有效生长期在中部和北部地区基本以2~4 d/10 a 的趋势显著增加。  相似文献   
295.
对川东北地区天然气勘探过程中的几项清洁生产技术措施进行了初步的分析,确定在取得良好的经济效益的同时,实现勘探过程中废弃物"减量化、无害化、资源化"的清洁生产目标,降低了勘探过程中的环境风险,同时也产生了良好的社会效益。  相似文献   
296.
首届"东北亚中亚区域可持续发展国际论坛"在北京召开。与会专家围绕着"全球气候变化背景下东北亚和中亚区域可持续发展"主题展开充分讨论,并形成重要研究结论。来自中国、俄罗斯、蒙古国、乌兹别克斯坦和以色列等国20多个研究机构的7位科学院院士、9位研究所所长和200多位专家学者讨论认为,面对积极应对全球变化的国际态势,加强东北亚中亚可持续发展国际合作研究具有重大战略意义,并向东北亚和中亚地区各国政府和专家学者发出共同倡议。此次国际论坛对加强东北亚和中亚地区在全球变化背景下资源生态环境与可持续发展科学问题与规律的国际合作研究具有重要推动作用。  相似文献   
297.
1900年以来东北深源地震区6.0级以上深源地震与黑龙江及邻近地区5级左右浅源地震存在较好的对应关系。通过概率增益模型检验这种对应关系,发现并非随机对应,而是存在一定的内在物理联系。通过B分布函数的概率计算,预测2010年2月19日中俄交界6.5级地震后两年内,黑龙江及邻近地区发生5级左右地震的概率为0.58。  相似文献   
298.
Freshwater scarcity is no longer limited to sub-Saharan developing countries; also in Western society, access to unlimited amounts of freshwater is not assured at all times. It has been argued - and laid down in many national legal systems - that access to freshwater is a basic human right. What if corporate freshwater use threatens to interfere with this human right? The main focus of the article is to explore the role of today’s companies in relation to freshwater. A number of tools have been developed to attend to the necessity to reduce corporate use of freshwater. The article discusses specialised water reporting instruments such as the 2007 Global Water Tool and the ‘water footprint’ calculation method. In addition, attention is paid to a CERES report (2010) revealing that the majority of the 100 world’s leading companies in water-intensive industries still has weak management and disclosures of water-related risks and opportunities. To obtain concrete information about corporate water strategies and practices, an explorative analysis was conducted on 20 Dutch multinational companies. The article highlights various innovative practices. In sum, it is demonstrated that companies are expected to bear responsibility for their impact on water resources, in particular when it influences public access to water in areas with freshwater scarcity and/or weak government. Notwithstanding the critical conclusions of the CERES report, it is interesting to see an evolution in corporate research concerning sustainable water use and the development of greener products and greener ways of production.  相似文献   
299.
Municipal solid waste management is a major environmental issue in India. Due to rapid increase in urbanization, industrialization and population, the generation rate of municipal solid waste in Indian cities and towns is also increased. Mismanagement of municipal solid waste can cause adverse environmental impacts, public health risk and other socio-economic problem. This paper presents an overview of current status of solid waste management in India which can help the competent authorities responsible for municipal solid waste management and researchers to prepare more efficient plans.  相似文献   
300.
Urbanization has created a significant gap between the Three Northeast Provinces (TNP) and the Yangtze River Delta (YRD) since China’s reform and opening-up. In this study, we explain this problem by employing an urban expansion index, spatial hierarchical clustering, the Zipf-PLE model, fractal theory, and time-series analysis. Statistical data on the built-up area, population, and gross domestic product were downloaded from the National Bureau of Statistics of China. The results revealed the following. (1) During the stage of the planned economy, as a result of the significant government investment in development, the urban built-up areas in the TNP and the YRD reached 1867 and 757 km2, respectively, in 1984. (2) During the stage of the socialist market economy, the urban built-up area of the YRD experienced rapid growth over the 30 years from 1984 to 2014 with a rate of increase of 668.8%, which was higher than that of the TNP (139.9%). In 2014, the urban built-up areas of the TNP and the YRD were 4479 and 5820 km2, respectively. (3) Locational advantages had significant effects on urban development after China’s economic reform. The coastal cities of the YRD had higher rates of increase of the built-up areas. By contrast, the border cities of the TNP had lower rates of increase. Finally, this paper finds that the socialist market economy exhibited more efficiency in promoting urban expansion and economic development. The results are significant for generating balanced and sustainable regional development strategies in the future.  相似文献   
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