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361.
This paper examines the impact of urban afforestation on infant health outcomes by exploiting a quasi-experimental setting where one million new trees were planted in New York City (NYC), but not in counties surrounding NYC over the same time period. Using a near-universal birth record of NYC and surrounding counties over 2004–2015 and employing both the synthetic control method and a difference-in-differences model, we find that an approximately 20% increase in urban forest cover decreased prematurity and low birth weight among mothers in NYC by 2.1 and 0.24 percentage points, respectively, relative to similar mothers outside of NYC. The low birth weight finding is equivalent to getting a mother smoking two cigarettes a day during pregnancy to quit. An internal validity test suggests that changes in the composition of NYC mothers cannot explain the observed effects. Additionally, we find evidence that declines in PM2.5 concentrations and increases in outdoor walks are potential causal mechanisms. Results suggest that urban afforestation may be able to complement existing policies aimed at improving infant health.  相似文献   
362.
We compared the composition of diatom assemblages collected from New Jersey Pinelands blackwater streams draining four different land uses, including forest land, abandoned-cranberry bogs, active-cranberry bogs, and developed and upland-agricultural land. Over a 2-year period (2002-2003), we collected 132 diatom taxa at 14 stream sites. Between-year variability in the composition of stream samples was high. Most diatom species were rarely encountered and were found in low abundance. Specific conductance and pH were higher at developed/agricultural sites compared with all other site types. Neither species richness nor genus richness was significantly different between stream types. However, clear community patterns were evident, and a significant difference in species composition existed between the developed/agricultural sites and both cranberry and forest sites. The primary community gradient, represented by the first axis of a DCA ordination, was associated with variations in pH and specific conductance. Although community patterns revealed by ordinating the data collected in 2002 differed from those obtained using the 2003 data, both ordinations contrasted the developed/agricultural sites and the other sites. Acidobiontic and acidophilous diatoms characterized the dominant species at forest, abandoned-bog, and cranberry sites, whereas indifferent species dominated the developed/agricultural samples. Although our study demonstrated a relationship between the composition of diatom assemblages and watershed conditions, several factors, including taxonomic problems, the large number of diatom species, incomplete pH classifications, and year-to-year variability may limit the utility of diatom species as indicators of watershed conditions in the New Jersey Pinelands.  相似文献   
363.
The effect of dairy farming on water quality in New Zealand streams has been identified as an important environmental issue. Stream fencing, to keep cattle out of streams, is seen as a way to improve water quality. Fencing ensures that cattle cannot defecate in the stream, prevents bank erosion, and protects the aquatic habitat. Stream fencing targets have been set by the dairy industry. In this paper the results of a study to identify the factors influencing dairy farmers' decisions to adopt stream fencing are outlined. Qualitative methods were used to gather data from 30 dairy farmers in four New Zealand catchments. Results suggest that farm contextual factors influenced farmers' decision making when considering stream fencing. Farmers were classified into four segments based on their reasons for investing in stream fencing. These reasons were fencing boundaries, fencing for stock control, fencing to protect animal health, and fencing because of pressure to conform to local government guidelines or industry codes of practice. This suggests that adoption may be slow in the absence of on-farm benefits, that promotion of stream fencing needs to be strongly linked to on-farm benefits, and that regulation could play a role in ensuring greater adoption of stream fencing.  相似文献   
364.
为解决改扩建项目环评中"以新带老"的重点和难点问题,结合医疗废物焚烧处置厂项目环评实例,说明如何利用实测数据和现场调查相结合的方式分析和解决"以新带老"问题,结果表明这两种方式缺一不可。  相似文献   
365.
为学习和借鉴国外发达国家先进的生态和环境保护经验,研究了澳大利亚和新西兰自然生态和城市环境保护工作,分析了两国在自然生态保护、农业可持续发展、城市基础设施建设方面的特点,总结了两国在城市内河治理、挥发性气体回收、公众环保参与形式及固体废物回收利用等方面的经验,提出了中国生态与环境保护工作的建议。  相似文献   
366.
新北市位于台湾本岛最北端,东北与基隆市为邻,东南接宜兰县,西邻桃园县,中间环绕台北市。新北地形以盆地、谷地为主。对比分析了南京市与新北市在社会经济、环境质量现状、环保体制机制方面的差异,介绍了新北市在在河川治理、空气质量改善、生活垃圾处理处置以及环保宣教等环保工作中的经验和做法,最后,对南京的环保工作提出了几点建议,以供决策参考。  相似文献   
367.
Knowledge of particle number size distribution(PND) and new particle formation(NPF)events in Southern China is essential for mitigation strategies related to submicron particles and their effects on regional air quality,haze,and human health.In this study,seven field measurement campaigns were conducted from December 2013 to May 2015 using a scanning mobility particle sizer(SMPS) at four sites in Southern China,including three urban sites and one background site.Particles were measured in the size range of15-515 nm,and the median particle number concentrations(PNCs) were found to vary in the range of 0.3× 10~4-2.2 × 10~4 cn~(-3) at the urban sites and were approximately 0.2 × 10~4 cm~(-3) at the background site.The peak diameters at the different sites varied largely from 22 to 102 nm.The PNCs in the Aitken mode(25-100 nm) at the urban sites were up to 10 times higher than they were at the background site,indicating large primary emissions from traffic at the urban sites.The diurnal variations of PNCs were significantly influenced by both rush hour traffic at the urban sites and NPF events.The frequencies of NPF events at the different sites were0%-30%,with the highest frequency occurring at an urban site during autumn.With higher SO_2 concentrations and higher ambient temperatures being necessary,NPF at the urban site was found to be more influenced by atmospheric oxidizing capability,while NPF at the background site was limited by the condensation sink.This study provides a unique dataset of particle number and size information in various environments in Southern China,which can help understand the sources,formation,and the climate forcing of aerosols in this quickly developing region,as well as help constrain and validate NPF modeling.  相似文献   
368.
武汉东湖新技术开发区是首批国家新技术产业开发区之一,为了促进开发区的环境与经济的协调发展,加强东湖新技术开发区的环境保护,笔者对东湖新技术开发区环境质量现状进行了调查研究,初步摸清了该区域环境质量状况,指出了目前开发区建设中应重视的环境管理问题,并对开发区的环境保护提出了一些建议,该项研究具有明显的社会和环境效益,对改善武汉市是东湖开发区的投资环境,提高人民生活水平和质量,树立城市新形象有着重要的现实意义。  相似文献   
369.
在对上海嘉定区农民新村污水纳管,污水处理及污水最终排放去向作全面调查的基础上,分析了农民新村污水排放现状.存在的主要问题和发展趋势,并从排水管网基础建设、污水就地处理技术应用、环保部门执法监督和农民环境意识提高等方面,剖析了问题的根源,阐述了解决问题的思路,并得出相应的对策和建议。  相似文献   
370.
新世纪企业环境战略研究   总被引:1,自引:1,他引:1  
汪勇  裴洪平 《重庆环境科学》2002,24(2):14-16,20
介绍了环境营销的定义,开展环境营销的必要性及其给企业和社会带来的好处,指出在新世纪,为了实现可持续发展,企业不仅要做好自身的污染防治工作,更应变被动为主动,选择环境营销导向,从战略的高度来审视企业的环境活动和行为,并对企业进行重新组织,同时本文还对企业建立环境营销战略的具体环境行为作了进一步探讨。  相似文献   
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