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781.
This paper investigates the sandy desertification change between 1986 and 2000 in the western Jilin province, North China. Land use and land cover data were obtained from Landsat TM data by using a supervised classification approach. We summarized the total area of desertified land by each county, as well as the area for each of the four categories of desertified land. The changes of different types of land use and land cover between 1986 and 2000 were calculated and analyzed. Taking Tongyu and Qianan as examples, both human and natural driving forces of the sandy desertification were analyzed. Our analyses indicate that the material sources and windy, warm and dry climate are the immanent causes of potential land desertification, while the irrational human activities, such as deforestation, reclaiming and grazing in the grassland, are the external causes of potential land desertification. However, rational human activities, such as planting trees and restoring grassland can reverse the land desertification process. Furthermore, the countermeasures and suggestions for the sustainable development in ecotone between agriculture and animal husbandry in North China are put forward.  相似文献   
782.
Human activities have impacted the environment since the first toolmakers learned to make fire. As the human population has grown and changed, so has our impact on the environment. Currently the world's population is estimated at 6–7 billion, and that number of people, along with the billions of domesticated animals, and their activities, are large enough to have major global and regional impacts. Climate change, declining fish populations in the oceans, and ever decreasing ranges for “wild” ecosystems are the most obvious impacts. Other impacts may be surprising to many people, especially those impacts that are regional and not raised to the level of international concern.This paper will take a very high level look at a number of global, regional and local human interactions with the environment, and how mitigating those impacts requires a very broad and multi-disciplinary response. Examples will focus on water, carbon and energy, all of which are needed for life, as we know it, to exist. Stewardship will be shown to involve determination and monitoring of many key indicators and environmental processes, followed by the tough decisions on how to steward those processes to maintain a healthy environment for all the planet's inhabitants. Stewardship is not easy, and there are few cases where solutions can be neatly divided into good or bad, positive or negative.  相似文献   
783.
Water is a resource that is essential for all life on Earth. An exponentially growing human population, in addition to unprecedented industrial and technological development, threaten the availability and quality of this resource. Climate change and ozone depletion are two major environmental problems facing mankind today. These problems have the potential to further strain currently available freshwater resources. Recent research has shown that climate change and ozone depletion are linked phenomena and their interaction exacerbates their impact. Changes in precipitation, surface runoff, solar UV radiation, temperatures, and evaporation are some of the predicted outcomes of climate change and ozone depletion. They influence the biogeochemical cycles and aquatic ecosystems in lakes and rivers, and alter the character of natural organic matter (NOM) and, consequently, they have the potential to affect the quality, quantity and treatability of our water resources. Given these uncertainties, and the need to mitigate the consequences of climate change and ozone depletion, the issues of changing water quality, quantity and treatability cannot be ignored by Australian governments and water utilities.  相似文献   
784.
孙君  王志峰 《环境与发展》2020,(4):27-27,29
通过Quick Bird、ZY-3商业卫星影像遥感解译提取台雄水库周围区域2008年、2018年共2期的土地利用数据,基于叠图法、景观指数法分析了水库建设前后土地利用空间分布格局、变化特征等。主要结论如下:台雄水库采取了有效的植被恢复措施,工程建设对自然植被尤其是森林植被的影响有限,工程建设和运行基本未改变生态系统总体异质性,对区域生态体系的阻抗稳定性影响不大。  相似文献   
785.
Global change affects alpine ecosystems by, among many effects, by altering plant distributions and community composition. However, forecasting alpine vegetation change is challenged by a scarcity of studies observing change in fixed plots spanning decadal-time scales. We present in this article a probabilistic modeling approach that forecasts vegetation change on Niwot Ridge, CO using plant abundance data collected from marked plots established in 1971 and resampled in 1991 and 2001. Assuming future change can be inferred from past change, we extrapolate change for 100 years from 1971 and correlate trends for each plant community with time series environmental data (1971–2001). Models predict a decreased extent of Snowbed vegetation and an increased extent of Shrub Tundra by 2071. Mean annual maximum temperature and nitrogen deposition were the primary a posteriori correlates of plant community change. This modeling effort is useful for generating hypotheses of future vegetation change that can be tested with future sampling efforts.  相似文献   
786.
Garrelts H  Lange H 《Ambio》2011,40(2):200-209
The spatial and temporal repercussions of climate change are of an extremely complex nature. Coping with climate change is, first and foremost, a challenge to political decision making and, considering the long-term effects of the climate system, to planning. However, there have never been more doubts that the political-administrative system is able to meet these requirements. Although much evidence has been put forward in favor of such skepticism, sometimes, it is dangerous to overstate the existing limits. Drawing on two case studies in the area of flood risk management in Germany, the article illustrates how and why significant path change came about. In both cases, the state proved to still being a pivotal actor, due to a number of functions that cannot be assumed by other actors. However, other actor groups—such as actors from science, the media, NGOs, and citizen groups—play a significant role as well by providing relevant expertise and influencing the public discourse, thus mobilizing significant political pressure.  相似文献   
787.
Poland is the largest hard coal producer in the European Union (EU), and remains very dependent on coal for its energy. Despite the significant long-term implications of EU mitigation policies for the Polish economy, coverage of climate change and policy in the Polish media remains very low. This study of the coverage both in print media and on television of the 2013/2014 Assessment Reports by the Intergovernmental Panel on Climate Change shows that the volume of coverage in Poland was much lower than in other European countries. The article explores possible reasons for the “exceptionalism” found in the Polish media.  相似文献   
788.
Robert Ladrech 《环境政策》2019,28(6):1017-1038
ABSTRACT

Political parties are important actors in domestic climate politics. What drives variation in parties’ climate policy preferences? To contribute to a growing literature on the party politics of climate change, we focus on the roles of public opinion, party competition, and parties’ traditional policy preferences in shaping parties’ climate policy preferences in Denmark and Ireland. In case studies that draw on in-depth interviews with policy practitioners, we show how parties respond to public opinion, accommodate issue-owners, and are powerfully constrained and enabled by their existing preferences. These mechanisms also help to explain different responses on climate policy across the left-right spectrum. Competition between mainstream parties is particularly powerful, but can constrain as much as it enables ‘greener’ climate policy preferences. While climate change may be a distinctive problem, the party politics of climate change features similar incentives and constraints as other domains.  相似文献   
789.
At the 2009 Copenhagen Climate Summit, donors pledged to ‘jointly mobilize’ $100 billion/year for climate finance by 2020. The Copenhagen Accord and other agreements do not specify who should provide how much of this collective target beyond the general principle of common but differentiated responsibilities and respective capabilities (CBDR&RC), according to which the more responsible a country is for climate change and/or the more capable of paying, the more climate finance it should provide. Two additional burden-sharing mechanisms may explain how much climate finance donors provide: willingness to pay or ‘greenness’ and self-interest. These mechanisms are tested to determine which best explains current patterns in climate finance commitments by analysing bilateral climate aid. There is evidence for capability—richer countries provide more climate aid. In contrast, responsibility, greenness or self-interest do not induce more climate aid commitments. Better understanding the drivers of climate aid helps to mobilize more climate finance, and advances understanding of (sectoral) aid allocation.  相似文献   
790.
The fossil fuel divestment movement has been a vibrant novel development in climate change politics in recent years, particularly in North America. Here, the character of the discourse used to promote divestment as a strategy is explored. The divestment discourse is shown to rest on four overlapping narratives, those of war and enemies, morality, economics and justice. All four are clearly discernible in statements from movement activists, in coverage of divestment campaigns by major news sources and in the movement’s aims, objectives and strategies covered in alternative media. The war narrative, with the formulation of fossil fuel companies as enemies to be overcome to ensure survival, is the dominant narrative. By polarising climate action and identifying an antagonist against which to mobilise, divestment discourse has articulated climate change as an explicitly political phenomenon, in contrast to the primarily consensus and collaboration-based approaches that have predominated in climate politics.  相似文献   
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