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141.
Model-based scenarios of water use in two semi-arid Brazilian states   总被引:2,自引:0,他引:2  
Sustainability-oriented water management calls for scenarios of future water use. Model-based qualitative-quantitative scenarios combine the development of story lines and the quantification of driving forces with the application of a water use model. In order to support regional planning in two semi-arid Brazilian states suffering from water scarcity, the water use model NoWUM was applied to derive two reference scenarios of municipality-specific sectorial water uses (irrigation, livestock, household, industry and tourism), and to assess the impact of certain interventions. Until 2025, the extension of irrigation accounts for almost 80% of the additional water withdrawals and for an even higher fraction of consumptive use in both scenarios. Domestic and industrial use increases in regions with high immigration, but water use intensities can be controlled by appropriate water pricing. A significant improvement of the developed scenarios is only possible if better data on water use and its driving forces become available. Electronic Publication  相似文献   
142.
Historical alterations of nitrogen deposition in the western part of Germany were investigated by comparing nitrogen concentrations and 15N natural abundance of historical and recent samples of the two pleurocarpous mosses Pleurozium schreberi and Scleropodium purum. Pooling of the data revealed only slight tissue N increases over the past 140 years which were significant nevertheless. At closer examination on the single site level historical increases of N concentrations were found particularly for some sites in regions where agricultural activities were considerably intensified during the second half of the 20th century. The comparison of δ15N values showed a strong depletion of 15N natural abundance in areas currently heavily influenced by livestock management. This indicates an increased impact of NHy compounds. However, the almost unchanged δ15N values in some low mountain range areas with only moderate intensification of agriculture point to a more or less constant ratio of NHy/NOx input over time. Significant correlations of both tissue N concentrations and 15N natural abundance between the two species justify the assumption that they use the same nitrogen source, probably atmospheric deposition.  相似文献   
143.
探讨了我国区域循环经济的发展模式,结合我国已有的循环经济实践,提出并分析了企业集团型、社会功能型、城市功能型和生态功能型4种区域循环经济的发展模式。  相似文献   
144.
我国区域性水体农药污染现状研究分析   总被引:5,自引:0,他引:5  
以4大流域为基础,较为全面地概述了我国区域性农药污染情况,并对其污染原因进行了分析。结果表明:长江流域有机磷农药、氨基甲酸酯类农药以及部分拟除虫菊酯类农药的的残留量很高;珠江流域农药污染情况较轻,检出量均低于我国地表水环境质量标准;黄淮海流域和松辽流域主要检出农药为酰胺类和三嗪类农药,但具体检出物质存在差异。研究分析表明各流域农药污染与该区域的农作物种类有重要关系。  相似文献   
145.
Geographic proximity is said to be a key characteristic of the resource reuse and recycling practice known as industrial symbiosis. To date, however, proximity of symbiont companies has remained an abstract characteristic. By conducting a statistical analysis of synergies facilitated by the United Kingdom's National Industrial Symbiosis Programme during their first five years of operation, this article attempts to quantify geographic proximity and in the process provide practitioners with an insight into the movement trends of different waste streams. Among other it was found that the median distance materials travelled within a symbiotic relationship is 20.4 miles. It is argued that quantitative information of this form is of practical value for the effective deployment of industrial symbiosis practitioners and wider resource efficiency planning. The results and discussion presented within this article are specific to industrial symbiosis opportunities facilitated within the United Kingdom; the methodology and assessment of resource movement influences are, however, expected to be relevant to all countries in which industrial activity is similarly mature and diversified.  相似文献   
146.
Urbanization is a dominant component of social and economic development around the world, but this process creates tremendous pressure on the ecological environment. How to achieve coordination between urbanization and conservation of this environment has become a key issue, especially in developing countries. It is necessary to identify the driving factors that affect this coordination. To identify these factors, we chose 290 Chinese prefecture-level cities to analyze the driving factors behind urbanization using spatial regression analysis, and explored the spatial differences among regions in these factors. Our results show that industrial upgrading and technological progress were the main factors that promoted coordinated development, with industrialization having positive effects under government management, but with differences among regions in how the driving forces affected coordinated development. Using technological progress to promote industrial upgrading, creating new employment to absorb surplus rural labor, and providing workers with skills training so they can take advantage of new jobs can promote win–win solutions that coordinate urbanization with conservation of the ecological environment.  相似文献   
147.
Fredrik Dalerum 《Ambio》2021,50(6):1259
Large carnivores are ecologically important, but their behaviour frequently put them in conflict with humans. I suggest that a spatial co-occurrence of suitable habitat and relatively poor socioeconomic conditions in rural areas may contribute to inflated human–carnivore conflict. Here, I test if there is potential for such an explanation for the human–wolf conflict in Sweden, a conflict that is arguably not congruent with the costs and damages imposed by the wolf population. I found negative correlations between wolf habitat suitability within Swedish municipalities and indicators of their relative socioeconomic conditions. I argue that geographic socioeconomic inequality may contribute to the Swedish human-wolf conflict, partly by the use of wolves as symbols for socioeconomic dissent and partly by using them as scapegoats for socioeconomic conditions. Therefore, regional policies aimed at alleviating geographic socioeconomic inequities may create a more favourable environment for solving the human-wolf conflict in Sweden.Supplementary InformationThe online version of this article (10.1007/s13280-021-01524-y) contains supplementary material, which is available to authorized users.  相似文献   
148.
This article reports the results of an examination of the relationships between degree of sprawl and improvements in ozone air quality for 52 metropolitan areas in the US. It also examines state political alignment and environmental resources with regard to these two primary objects of investigation. Evidence of a relationship between sprawl and air quality improvement was identified, but the evidence is ambiguous. More research appears warranted to explore the sprawl–air quality improvement relationship. Electronic Publication  相似文献   
149.
人力资本流动对地区经济增长差距的影响   总被引:1,自引:0,他引:1  
由于具有不同教育背景和不同技术条件的劳动力对流入地经济增长的推动肯定是不相同的.因而我们有必要分别考察具有不同人力资本含量的劳动力对流入地经济增长的贡献。本文引入了一个包含异质型流动人口变量的函数。并对1985—1990年期间我国分地区流动人口的素质状况对地区经济增长的影响进行了研究。研究结果显示,在此期间.仅流动人口中的智力资本就为我国的经济增长带来了大约72.5亿元国民生产总值的价值;而分地区的研究结果显示.流动人口中的智力资本也极大地促进了东部地区和西部地区的经济增长。但是,对中部来说,在此期间的流动人口不管是从对劳动力数量的增长贡献上。还是从对本地区人力资本存量的增长贡献上,都对本地区经济增长产生了消极的影响。  相似文献   
150.
The role of PM2.5 (particles with aerodynamic diameters ≤ 2.5 µm) deposition in air quality changes over China remains unclear. By using the three-year (2013, 2015, and 2017) simulation results of the WRF/CUACE v1.0 model from a previous work (Zhang et al., 2021), a non-linear relationship between the deposition of PM2.5 and anthropogenic emissions over central-eastern China in cold seasons as well as in different life stages of haze events was unraveled. PM2.5 deposition is spatially distributed differently from PM2.5 concentrations and anthropogenic emissions over China. The North China Plain (NCP) is typically characterized by higher anthropogenic emissions compared to southern China, such as the middle-low reaches of Yangtze River (MLYR), which includes parts of the Yangtze River Delta and the Midwest. However, PM2.5 deposition in the NCP is significantly lower than that in the MLYR region, suggesting that in addition to meteorology and emissions, lower deposition is another important factor in the increase in haze levels. Regional transport of pollution in central-eastern China acts as a moderator of pollution levels in different regions, for example by bringing pollution from the NCP to the MLYR region in cold seasons. It was found that in typical haze events the deposition flux of PM2.5 during the removal stages is substantially higher than that in accumulation stages, with most of the PM2.5 being transported southward and deposited to the MLYR and Sichuan Basin region, corresponding to a latitude range of about 24°N-31°N.  相似文献   
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