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931.
利用1960~2012年长江三角洲地区气象观测资料,对长江三角洲区域雾和霾的时空分布及其影响因素进行了分析.结果表明:长江三角洲地区雾、霾分布不均匀,雾日大值区主要分布在江苏省盐城中部沿海地区、安徽省黄山地区、浙江东部沿海地区,霾日大值区主要分布在以南京、杭州、合肥、衢州为中心的周边城市.时间变化上,城市化水平高的大城市年雾日数在20世纪80年代之前呈增加趋势,之后呈减少趋势;城市化水平低的小城市年雾日数也呈先升后降的趋势,但下降时间滞后于大城市.大城市雾日月平均分布冬季最多,春秋季次之,夏季最少,小城市雾日月平均分布呈双峰型特征,即春季和冬季较多.大城市和小城市年平均霾日数一直呈增加趋势且20世纪90年代之后差距变大.区域气候变化和城市化导致的温度上升,空气污染加剧导致的气溶胶增加,是造成长江三角洲雾日、霾日不同变化特征的原因,但它们之间的相互作用效应复杂,值得深入研究.  相似文献   
932.
A new approach was developed to evaluate the implications of the spatiotemporal variability of green vegetation for the dispersion of livestock that is required to access quality forage in semi-arid Africa. Maximum NDVI (Normalized Difference Vegetation Index) at 1 km2 resolution was determined for concentric rings (0–31 km radii) around 227 individual sample locations within the study area for 14 dates (between 1 April to 1 November) annually over the 2000–2010 period. A sigmoidal curve was fitted to points within the maximum NDVI × distance radii space to determine the asymptote distance (AD) – the radius at which further dispersion from the sample location does not lead to significant gains in access to green forage. AD was found to: increase with latitude (or increasing aridity); decline as the rainy season proceeds; and show no trend over the 2000–2010 period. These results introduce much-needed empirical data to current debates surrounding the scales of governance to support livestock mobility.  相似文献   
933.
During the 1997–98 El Niño, Tumbes, Peru received 16 times the annual average rainfall. This study explores how Tumbes residents perceived the impact of the El Niño event on basic necessities, transport, health care, jobs and migration. Forty‐five individuals from five rural communities, some of which were isolated from the rest of Tumbes during the event, participated in five focus groups; six of these individuals constructed nutrition diaries. When asked about events in the past 20 years, participants identified the 1997–98 El Niño as a major negative event. The El Niño disaster situation induced a decrease in access to transport and health care and the rise in infectious diseases was swiftly contained. Residents needed more time to rebuild housing; recover agriculture, livestock and income stability; and return to eating sufficient animal protein. Although large‐scale assistance minimized effects of the disaster, residents needed more support. Residents' perspectives on their risk of flooding should be considered in generating effective assistance policies and programmes.  相似文献   
934.
Considering the significant roles of the policies in developing environmental finance, an overview is conducted on the environmental finance policies (EFPs) in China. This paper analyzed the definition, scope, evolution and main instruments of EFPs. The implementation progress of financial activities on each instrument are investigated respectively. Then the experiences learned from and failures discovered in the development of the EFPs are discussed well recommendations for further improvement of the EFPs and their implementation are provided. Our study found that the EFPs have been established in China after a four-phase evolution since the early 1980s. The policies have played a critical role in leading to a rapid development in environmental finance by involving more financial instruments to accomplish the objective-led environmental plans. Driven by the policies, the new green credit (GC), green security (GS), and green insurance (GI) instruments have been phased in as supplements to the conventional command and control approaches to improve the environmental governance of financial activities and pollution sources. However, the market mechanism of financial institution is limited due to their defensive and incapable performance on implementation some of EFP instruments. To further strengthen the effectiveness of EFPs in facilitating environmental man- agement, recommendations are made mainly on the aspects including developing more specific policy guidelines, enhancing information sharing and disclosure, providing sufficient economic incentives, establishing environmental liabilities with financial activities, and involving issues related to climate change, and biodiversity and ecosystem service.  相似文献   
935.
SUMMARY

The emerging concept of industrial ecology (IE) has been applied in practice in few case studies on local/regional industrial recycling networks. Analogously to a natural ecosystem, the aim is to develop material cycles and energy cascades between local cooperative actors. An optimal resource basis of an industrial ecosystem is the sustainable use of local renewable natural resources. In this paper, we consider the region of North Karelia in Finland, with 19 municipalities, and hence somewhat expand the system boundaries of an industrial ecosystem case study. The current situation and two scenarios of municipal heating energy production are presented. The heating system consists of individual, district and electric heating. The heat production and related greenhouse gas emissions are considered. The current fuel use is based on imported oil and regional fuels (peat, wood wastes). Also, shares for co-production of heat and electricity (CHP) are shown. In scenario one, we assume the majority of the fuel basis in oil and absence of CHP. Scenario two illustrates nearly complete dependence on regional wood wastes and firewood with the current share of CHP. The North Karelia region provides the IE theory with a fruitful case study because the supply of waste fuels and local renewables is vast and waste utilisation technologies (CHP, fluidized bed burning) constitute a significant part of energy production. Implications of the applied scenario approach are discussed in the context of regional decision making and, in particular, for its implementation with the concepts of a regional environmental management system (EMS) and a regional industrial ecosystem management system (RIEMS).  相似文献   
936.
Internalizing the global negative externality of carbon emissions requires the flattening of the extraction path of world fossil energy resources (=world carbon emissions). We consider governments with sign-unconstrained emission taxes at their disposal and seeking to prevent world emissions from exceeding some binding aggregate emission ceiling in the medium term. Such a ceiling policy can be carried out either in full cooperation or by a sub-global climate coalition. Unilateral action has to cope with carbon leakage and high costs, which makes a strong case for choosing a policy that implements the ceiling in a cost-effective way. In a two-country, two-period general equilibrium model with a non-renewable fossil-energy resource, we characterize the unilateral cost-effective ceiling policy and compare it with its fully cooperative counterpart. We show that with full cooperation there exists a cost-effective ceiling policy in which only first-period emissions are taxed at a rate that is uniform across countries. In contrast, the cost-effective ceiling policy of a sub-global climate coalition is characterized by emission regulation in both periods. The share of the total stock of energy resources owned by the sub-global climate coalition turns out to be a decisive determinant of the sign and magnitude of unilateral cost-effective taxes.  相似文献   
937.
陕西2012年极端天气气候事件与气象灾害   总被引:1,自引:0,他引:1  
利用极端天气气候事件监测系统监测结果,分析了陕西1981-2012年极端天气气候事件出现次数和强度,发现2012年陕西极端天气气候事件次数少于多年平均值,但华阴7月2-4日、佳县7月24-28日极端降水事件强度之大,为历史罕见,佳县27日降水量、26-28日3d降水量均超过百年一遇的水平,造成严重人员伤亡和经济损失.说明即便是在极端天气气候事件出现次数少,气候年景较好的年份,局地也会出现历史罕见的极端事件和灾害.此外,还分析了极端天气气候事件次数与灾情年景评估指数之间的相关性.  相似文献   
938.
《Environmental Hazards》2013,12(3):229-247
Focusing on three of the largest coastal cities in the Republic of Ireland, this paper highlights the importance of a historical analysis of flood hazards in contextualising current events and potential future risks. Over the last decade, the cities of Dublin, Cork and Galway have experienced several major coastal, river and pluvial floods. In the aftermath of these floods, two distinct but related narratives have dominated public discourse and official responses. The first narrative presents recent floods as unprecedented and as possible evidence of climate change. The second constructs floods primarily as natural events and assumes that the optimal means of reducing flood losses is to prevent flood events. In this paper, I suggest that these narratives are not supported by a historical analysis of exposure and vulnerability to flood hazards in Irish cities. This paper draws primarily on newspaper archives to construct a record of past flooding that challenges these narratives in several ways and in doing so offers lessons for similar cities in other countries. I contend that these narratives are perpetuated by a narrow form of knowledge production (quantitative risk assessment) and a narrow range of data (numeric instrumental records). Incorporating a broader range of sources and data types into risk and vulnerability assessments may illuminate more creative strategies for reducing both contemporary and future flood losses.  相似文献   
939.
《Environmental Hazards》2013,12(2):149-163
This research attempts to improve understanding of how climate change may affect international humanitarian spending, using existing international databases that track disaster occurrence and humanitarian costs. A range of potential impact scenarios is developed employing four distinct methodological approaches. The findings indicate that climate change will have a significant impact on humanitarian costs and the increase could range from a 32 per cent increase (taking into account only changes in frequency of disasters) to upwards of a 1,600 per cent increase when other criteria, such as intensity, are also taken into account. The paper further highlights that extreme weather events do not occur in isolation and the increasing interconnectedness of world economic and political systems has made disasters more complex and destructive. It makes a number of recommendations, including the need for more rigorous and systematic collection of disaster-related data and more constructive interaction between the humanitarian and climate change communities on future research, planning and action.  相似文献   
940.
Africa is most vulnerable to climate change, although it makes the least contribution to factors that result in global and regional climatic changes. High levels of vulnerability and low adaptive capacity across the continent have been linked to, among other things, poverty. This paper discusses and analyses the relationship between climate change and poverty in Africa. It investigates the relationship between climate change and poverty patterns in Africa, analyses the resultant impact, and discusses potential adaptation policies for moderating the consequences of climatic changes on poverty in the region. The record shows that climate change is happening. What is not discussed or is little researched is the potential devastating impact of climate change on socio-economic development in Africa and the policy measures available to the continent for adaptation.  相似文献   
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