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121.
地球气候变化既有自然因素又有人为因素,全球变暖主要原因是人类活动温室气体排放过度。因此,在应对气候变化问题上,人们对减排温室气高度重视是理所当然,而长期以来对"适应气候变化"却有所忽视。其实,对发展中国家《适应气候变化》才是当务之急。本文在"发展低碳经济,应对全球变暖"减排二氧化碳温室气体的基础上,论述适应气候变化的迫切性和基本途径。  相似文献   
122.
摘要:对2006~2011年宜良县城NO2、SO2、PM10监测数据进行统计分析,认为SO2是县城的主要污染物。3种污染物年际浓度变化为:NO2、SO2下降趋势显著,PM10下降趋势不显著;季节浓度变化为:S02冬〉秋〉春〉夏,N02、PM10冬〉春〉秋〉夏,并提出防治建议。  相似文献   
123.
冬季黄东海颗粒有机碳的时空分布特征   总被引:1,自引:0,他引:1  
根据2007年1~2月对黄东海大面调查的资料,分析研究了黄东海颗粒有机碳(POC)的时空分布特征。结果表明,冬季黄东海POC的浓度范围是2.49~1 658.96μg/L,平均浓度为125.88μg/L。在垂直方向上,POC由上而下随着水深的增加浓度逐渐降低,到底层后浓度又升高。在平面分布上,POC整体上呈现西部近岸浓度较高、东部离岸浓度较低的特点;POC的高值区集中在浙江近岸海区,特别是浙江舟山群岛南部近海,POC浓度非常高,这是受陆源输入和沉积物再悬浮的共同作用。在周日变化上,受潮汐作用和海区生物活动的影响,东海陆架中部海域除底层以外,其它各层POC在午后、傍晚、凌晨出现浓度的高峰值,而西南海域,除了底层外,其它各层均表现出全日周期变化。  相似文献   
124.
大窑湾海域虾夷扇贝体内麻痹性贝毒的周年变化   总被引:3,自引:3,他引:0  
麻痹性贝毒是对人体健康构成严重危害的甲藻类毒素。2007~2008年,大窑湾虾夷扇贝体内麻痹性贝毒2周年的调查发现,其含量与组分有着明显的季节变化,4-7月份麻痹性贝毒含量较高,4月份最高,平均含量可达378.32μg STXeq/100 g,有C1、C2、GTX1、GTX2、GTX3、GTX5、dcGTX2、dcGTX3、neoSTX、STX等10种毒素组分。大窑湾虾夷扇贝体内麻痹行贝毒组分显著增多,含量明显增高。  相似文献   
125.
突发性环境事件时间序列特征可表征环境风险管理成效及存在问题。研究表明2000年以来中国突发环境事件预防、控制与管理取得了显著成效,其中,突发性水污染事件、大气污染事件以及噪声振动危害年发生频次呈大幅度降低趋势,但固废污染事件自2003年以来的年发生频次变化不大,而其它突发性环境事件自2002年以来的年发生频次则呈快速增长态势,说明中国在强调突发性水环境和大气环境事件监管的同时,还需加强固废污染事件及其它类型突发环境事件的监控与管理。  相似文献   
126.
生态城市特征性指标的辨析及其应用   总被引:1,自引:0,他引:1  
生态城市是依据生态学原理提出的一类社会、经济、自然协调发展的城市.基于生态城市内涵建立的城市特征性指标对城市特征性要素的量化和评价,是将生态城市个性这一主观观念变为可操作性目标的主要途径.基于城市复合生态系统理论和生态城市"健康、安全和发展"内涵,探讨了生态城市特征性指标的辨析方法.以厦门为例构建了厦门生态城市特征性指标体系.评价结果揭示了厦门城市特有的生态环境和资源的总体状态为亚健康状态(0.69)、比较脆弱的中警状态(0.39)和一般持续的发展状态(0.63).与现实的分析调研结果相符.这表明生态城市特征性指标有助于研究者辨识和评价城市生态系统的特定复合特征,更有针对性地明确城市生态规划和建设的重点行动领域,从而为城市实施可持续发展战略提供决策依据.  相似文献   
127.
有机化改性海泡石对六六六吸附性能的探讨   总被引:1,自引:0,他引:1  
分别采用阴阳离子表面活性剂对海泡石进行有机化改性处理,并对改性海泡石进行了吸附六六六实验.结果表明,未经有机化改性的海泡石对六六六各异构体去除能力由小到大依次为:γ-六六六(12.66%)、δ-六六六(12.79%)、α六六六(17.35%)、β-六六六(33.57%).经DOSO3Na有机化改性的海泡石对六六六各异构体的去除能力由小到大依次为:β-六六六、γ δ-六六六、α-六六六.经CTMAB有机化改性的海泡石对六六六各异构体的去除能力由小到大依次为:β-六六六、α-六六六、γ δ-六六六.有机化改性海泡石使体系中β-六六六大幅度增加,可能为有机化海泡石催化α、γ、δ各异构体向β异构体转化.  相似文献   
128.
Determinants of adaptive and mitigative capacities (e.g., availability of technological options, and access to economic resources, social capital and human capital) largely overlap. Several factors underlying or related to these determinants are themselves indicators of sustainable development (e.g., per capita income; and various public health, education and research indices). Moreover, climate change could exacerbate existing climate-sensitive hurdles to sustainable development (e.g., hunger, malaria, water shortage, coastal flooding and threats to biodiversity) faced specifically by many developing countries. Based on these commonalities, the paper identifies integrated approaches to formulating strategies and measures to concurrently advance adaptation, mitigation and sustainable development. These approaches range from broadly moving sustainable development forward (by developing and/or nurturing institutions, policies and infrastructure to stimulate economic development, technological change, human and social capital, and reducing specific barriers to sustainable development) to reducing vulnerabilities to urgent climate-sensitive risks that hinder sustainable development and would worsen with climate change. The resulting sustainable economic development would also help reduce birth rates, which could mitigate climate change and reduce the population exposed to climate change and climate-sensitive risks, thereby reducing impacts, and the demand for adaptation. The paper also offers a portfolio of pro-active strategies and measures consistent with the above approaches, including example measures that would simultaneously reduce pressures on biodiversity, hunger, and carbon sinks. Finally it addresses some common misconceptions that could hamper fuller integration of adaptation and mitigation, including the notions that adaptation may be unsuitable for natural systems, and mitigation should necessarily have primacy over adaptation.
Indur M. GoklanyEmail:
  相似文献   
129.
India occupies 2.4% of the world’s geographical area with a large percentage of its land under agriculture. About 228 Million hectares (Mha) of its geographical area (nearly 69%) fall within the dryland (arid, semi-arid and dry sub-humid) region. Of the total cultivated area of 142 Mha, major part of agriculture in the country is rainfed, extending to over 97 Mha and constituting nearly 68% of the net cultivated area, therefore making the agricultural sector vulnerable and exposed to the vagaries of weather conditions. Climate change adds to this dimension of stress. A strong need is felt for targeting programmes in these areas that address issues related to employing suitable soil and water conservation measures. In this context this paper seeks to examine the case for watershed development as an adaptive strategy. An examination of the possibility of fortifying the existing programme with a view to adapting to expected changes in climate in future is undertaken. Also, the possibility of watershed development integrating into a suitable mitigation strategy for the country is assessed.
Preety M. BhandariEmail:
  相似文献   
130.
The possibility of adopting national targets for carbon dioxide (CO2) emissions from tropical deforestation in a future international climate treaty has received increasing attention recently. This attention has been prompted by proposals to this end and more intensified talks on possible commitments for developing countries beyond the United Nations Framework Convention on Climate Change Kyoto Protocol. We analyze four main scientific and political challenges associated with national targets for emissions from tropical deforestation: (1) reducing the uncertainties in emission inventories, (2) preserving the environmental integrity of the treaty, (3) promoting political acceptance and participation in the regime, and (4) providing economic incentives for reduced deforestation. We draw the following conclusions. (1) Although there are large uncertainties in carbon flux from deforestation, these are in the same range as for other emissions included in the current Kyoto protocol (i.e., non-CO2 GHGs), and they can be reduced. However, for forest degradation processes the uncertainties are larger. A large challenge lies in building competence and institutions for monitoring the full spectrum of land use changes in developing countries. (2 and 3) Setting targets for deforestation is difficult, and uncertainties in future emissions imply a risk of creating ‘tropical hot air’. However, there are proposals that may sufficiently deal with this, and these proposals may also have the advantage of making the targets more attractive, politically speaking. Moreover, we conclude that while a full carbon accounting system will likely be politically unacceptable for tropical countries, the current carbon accounting system should be broadened to include forest degradation in order to safeguard environmental integrity. (4) Doubts can be cast over the possible effect a climate regime alone will have on deforestation rates, though little thorough analysis of this issue has been made.
U. Martin PerssonEmail:
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