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921.
Renewable electricity policies promote investment in renewable electricity generators and have become increasingly common around the world. Because of intermittency and the composition of other generators in the power system, the value of certain renewable – particularly wind and solar – varies across locations and technologies. This paper investigates the implications of this heterogeneity for the cost effectiveness of renewable electricity policies. A simple model of the power system shows that renewable electricity policies cause different investment mixes. Policies also differ according to their effect on electricity prices, and both factors cause the cost effectiveness to vary across policies. We use a detailed, long-run planning model that accounts for intermittency on an hourly basis to compare the cost effectiveness for a range of policies and alternative parameter assumptions. The differences in cost effectiveness are economically significant, where broader policies, such as an emissions price, outperform renewable electricity policies. 相似文献
922.
J. A. Maynard J. E. Johnson P. A. Marshall C. M. Eakin G. Goby H. Schuttenberg C. M. Spillman 《Environmental management》2009,44(1):1-11
The frequency and severity of mass coral bleaching events are predicted to increase as sea temperatures continue to warm under
a global regime of rising ocean temperatures. Bleaching events can be disastrous for coral reef ecosystems and, given the
number of other stressors to reefs that result from human activities, there is widespread concern about their future. This
article provides a strategic framework from the Great Barrier Reef to prepare for and respond to mass bleaching events. The
framework presented has two main inter-related components: an early warning system and assessment and monitoring. Both include
the need to proactively and consistently communicate information on environmental conditions and the level of bleaching severity
to senior decision-makers, stakeholders, and the public. Managers, being the most timely and credible source of information
on bleaching events, can facilitate the implementation of strategies that can give reefs the best chance to recover from bleaching
and to withstand future disturbances. The proposed framework is readily transferable to other coral reef regions, and can
easily be adapted by managers to local financial, technical, and human resources. 相似文献
923.
Impact assessment (IA) is one of the most widely applied instruments for generating policy-relevant knowledge. However, the step-wise process, logic of linear knowledge transfer and influence of IA has frequently been criticised. Current IA procedures do not adequately address complex and unpredictable policy processes, such as the preparation of climate policies. Drawing on a framework of science–policy interface problems, we analyse knowledge exchange in a national climate policy IA case and discuss the reasons for the problems. We demonstrate various problems in knowledge use and production as well as in the balance between the demand for and supply of knowledge, such as ignoring the knowledge involved in the policy process, the monopoly held by certain knowledge providers and models, insufficient scoping and framing of the IA, poor interaction with knowledge providers and users, and inadequate planning and coordination of the process. We highlight the need for adding context-sensitive and tailored knowledge exchange practices to IA processes to enhance the use of existing knowledge in climate policy. 相似文献
924.
恢复力作为刻画人类自身响应和发挥主体能力、积极抵御和适应外界变化的指标,在灾害学领域的引入进一步丰富和明晰了灾害承灾体的性质,与脆弱性具有同等的重要性。但当前对灾害恢复力的研究不足,如何界定灾害恢复力的特征、诊断和定量评价恢复力尚存在较大的探讨空间。在湖南鼎城高排河流域野外土地利用现状测量与入户调查所得数据和气象数据的基础上,应用数学统计方法重点分析了土地利用、农户经济、文化素质状况等因素与农业旱灾承灾体恢复力的关系。结果表明,地貌类型与海拔高度从较大尺度上决定了农业旱灾承灾体恢复力的大小,水源地位置及其蓄水能力、水田与旱地的比例关系、劳动力文化水平、农户实际年收入和非农收入比例是影响农业旱灾承灾体恢复力的主要因素。 相似文献
925.
María Eugenia Ibarrarán Matthias Ruth Sanjana Ahmad Marisa London 《Environment, Development and Sustainability》2009,11(3):549-569
Commonly occurring natural events become natural disasters when they affect the population through death and injury, and/or
through the destruction of natural and physical capital on which people rely for their livelihood and quality of life. Climate
change plays a role in that it tends to increase the frequency and intensity of weather-related natural disasters. Additionally,
climate change may put people at risk by influencing access to water, coastal flooding, disease and hunger, and leaving them
with a more degraded environment, leading, in turn, to increased vulnerability. The purpose of this paper is to present a
review and synthesis of the literature and case studies addressing differential impacts of climate change-related natural
disasters on a society and its economy. Developed and developing countries show different vulnerabilities to natural disasters.
Even within countries, impacts vary significantly across population and economic sectors. When losses from natural disasters
are large, their cumulative effect can have notable macroeconomic impacts, which feed back to further pronounce existing income
inequalities and lower income levels. Impacts tend to be most pronounced for women, the young and elderly, and people of ethnic
or racial minorities.
相似文献
María Eugenia IbarraránEmail: |
926.
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
927.
We integrated basic concepts from fisheries science and toxicological risk assessment to form a potential method for setting
screening-level, risk-based, site-specific water quality objectives for temperature. In summary, the proposed approach: (a)
uses temperature impacts upon specific growth as a measure of chronic (cumulative) temperature effects; (b) explicitly incorporates
the consequences of both magnitude and cumulative duration of exposures; (c) adjusts the result for local watershed conditions,
reducing the likelihood that naturally warm systems are identified as thermally polluted while helping to ensure that naturally
cool systems are closely monitored for ecologically harmful changes in thermal regime; and (d) expresses the net result both
graphically and as a risk quotient, RQ, closely analogous to that used in toxicological risk assessments. The latter yields a site-specific, risk-based water quality
objective and may serve as a straightforward decision rule for environmental managers. The method was applied to historical
data from a small British Columbia stream subject to increasing urban development pressures. We also illustrate how the technique
might be used to explore potential climatic change impacts, using coupled general circulation model predictions in conjunction
with empirical downscaling. Overall, the method and results are presented as an introduction and illustration of concept,
intended as a step toward the development of a logistically feasible risk-based approach to establishing screening-level,
site-specific water temperature objectives, and monitoring compliance, in the context of large-scale, many-site, environmental
monitoring networks. With further work, the technique offers potential to fill the gap between the temperature threshold-based
targets typically specified in regulatory guidelines, which may be hydroecologically unrealistic, and detailed biophysical
modelling, which typically is logistically infeasible in a day-to-day environmental monitoring and management context. 相似文献
928.
为了观察农户生计活动复杂化过程,分析弹性在可持续生计中发挥的作用,推动扶贫开发战略从识别贫困人口向防御贫困转变,本文采用曲线拟合、核密度函数非参数估计算法等实证研究方法,利用陕西省安康农户生计与环境调查数据,基于脆弱性、适应性维度对农户生计多样性发展阶段进行了识别、划分,系统分析了弹性在农户、社区不同尺度上、阶段上对于农户生计脆弱性与适应性的作用过程。研究发现:生计多样性发展阶段随尺度有所不同,随着适应性提高,在社区尺度上,生计活动多样性指数先增加后减小,在农户尺度上,则是先减小后增加;农户生计活动存在高脆弱性、低适应性的尝试阶段,在经历了这个阶段之后,伴随着农户适应性的提高,脆弱性会同时增加;在社区尺度上,弹性作用下伴随着收入提高,脆弱性会逐步降低,在农户尺度上,弹性作用下伴随着收入提高,生计活动脆弱性会提高,形成"高风险、高收益"的情况。研究发现说明农户、社区存在着"多样性尝试"发展阶段,在一定尺度上保持适度脆弱性有利于社区、地域的可持续发展,作为联系不同尺度生计活动脆弱性、适应性的关键,农户在这个阶段完成生计多样性水平专业化过程,社区在这个阶段形成地区特色的生计活动。扶贫开发工作应把握好这一时机,提高工作措施效果和绩效。在扶贫开发工作实践中,在目标制定上不仅需要考虑收入因素,还需要考虑生计活动复杂性因素,政策措施充分利用"多样性尝试"发展时机,同时主动开展替代生计研究、落实工作,提高贫困防御能力,推动农户、社区可持续发展。 相似文献
929.
Rebecca J. Romsdahl Andrei Kirilenko Robert S. Wood Andy Hultquist 《Environmental Communication: A Journal of Nature and Culture》2017,11(4):515-536
While many national governments struggle to maintain global climate change as a high priority issue, many local governments are taking action to fill the policy gaps. This study examines how local governments across the United Kingdom of Great Britain are reframing climate change. We compiled a dataset of newspaper publications covering climate change over a 10-year timeframe, plus survey and interview responses from local governance practitioners, to identify a shift in national discourse that has changed the priority level of climate change in UK local governance. This paper argues that many local governments are strategically reframing climate change as alternative issues in order to make progress in climate adaptation planning. 相似文献
930.
Ken’ichi Matsumoto Kanako Morita Dimitrios Mavrakis Popi Konidari 《International Journal of Green Energy》2017,14(8):724-736
In Japan, the Renewable Portfolio Standard (RPS) and the Feed-in-Tariff (FIT) have been used for the exploitation of renewable energy sources (RES). Although these are significant to enhance the use of RES, the RES penetration is not reaching the expected percentage. The identification of their strengths/weaknesses will allow their improvement for achieving the target. This paper concerned the evaluation of RPS and FIT using a multi-criteria evaluation method. First, official data/information were used to assess their performance using the method. Second, national experts were asked about their performance to verify the outcomes. We found FIT was more effective than RPS. 相似文献