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871.
新疆伊犁州2000~2005年生态环境质量变化评价与分析   总被引:1,自引:1,他引:0  
利用Landsat-5 TM遥感影像解译的土地利用数据分析了新疆伊犁州(州直辖)2000~2005年的土地利用变化,同时根据<生态环境状况评价技术规范>(试行)(HJ/T192-2006),对该区域生态环境质量状况进行综合评价,对生态环境指标变化情况进行对比分析.结果表明,2000~2005年伊犁州的生态环境质量均为一般,生态环境质量指数(E1)减少0.71.主要原因为草地面积明显减少,耕地面积明显增加.  相似文献   
872.
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   
873.
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   
874.
Solar radiation management (SRM) has been proposed as a means of last resort against dangerous climate change. We propose a stylized model of intergenerational decision making on SRM research, greenhouse-gas abatement and SRM deployment, under uncertainties about (a) the extent of future climate damage and (b) effectiveness and potential harmful side-effects of SRM. Open-ended research may reveal either that SRM effectively reduces climate damage, or that it would cause more harm than benefits. We find that SRM research increases the likelihood of deployment (“slippery slope”), and derive conditions that it decreases abatement effort in expectation (“moral hazard”). Neither of these provides a rationale against SRM research, though. The rational decision is to perform SRM research, unless (i) discounting is hyperbolic and (ii) the absolute prudence of expected climate damage is smaller than absolute risk aversion. These results generalize to the case where SRM research also provides information on climate sensitivity.  相似文献   
875.
This paper investigates the social costs of second-best agricultural greenhouse gas (GHG) mitigation policies. Adjustments along the land use and input intensity margins are represented within a regionalized optimization model of California crop production calibrated to economic and agronomic information. Second-best policies relying on spatially aggregated GHG emission factors lead to small abatement efficiency losses, while policies targeting a single GHG lead to moderate losses. In contrast, policies targeting a single input entail large abatement efficiency losses, which nonetheless can be reduced by combining instruments.  相似文献   
876.
We model climate change as a dynamic game and prove existence of a unique subgame-perfect Nash equilibrium (SPNE) that is also Markov perfect. We interpret this unique SPNE as the business-as-usual (BAU) equilibrium and show that if the countries are not sufficiently symmetric then the familiar trigger strategy equilibria may not be Pareto improvements over the BAU equilibrium and may even lack efficiency properties. We then motivate and introduce a subgame-perfect cooperative agreement as an improvement over the BAU equilibrium in the sense that every country or coalition of countries is better off in every subgame, irrespective of the extent of heterogeneity of the countries. We characterize subgame-perfect cooperative agreements and identify sufficient conditions for their existence. We show that (direct or indirect) transfers between countries to balance the costs and benefits of controlling climate change are a necessity and not a matter of approach.  相似文献   
877.
This paper empirically estimates the economic impacts of a large-scale public investment in natural infrastructure aimed at adapting to climate change and increasing coastal resilience. I utilize temporal and spatial variation in investment in dunes to provide a hedonic property value estimate of the economic benefits. I identify the net effect of treatment utilizing the doubly robust Oaxaca-Blinder estimator and show that coastal housing price increases attributable to constructed dunes are approximately 3.6%. A decomposition of the average impact suggests that the policy intervention generates ancillary costs related to impaired ocean views and privacy concerns that partially offset large protection benefits.  相似文献   
878.
Foreword     
Wassmann P  Lenton TM 《Ambio》2012,41(1):1-9
We provide an introduction to the volume The Arctic in the Earth System perspective: the role of tipping points. The terms tipping point and tipping element are described and their role in current science, general debates, and the Arctic are elucidated. From a wider perspective, the volume focuses upon the role of humans in the Arctic component of the Earth system and in particular the envelope for human existence, the Arctic ecosystems. The Arctic climate tipping elements, the tipping elements in Arctic ecosystems and societies, and the challenges of governance and anticipation are illuminated through short summaries of eight publications that derive from the Arctic Frontiers conference in 2011 and the EU FP7 project Arctic Tipping Points. Then some ideas based upon resilience thinking are developed to show how wise system management could ease pressures on Arctic systems in order to keep them away from tipping points.  相似文献   
879.
It seems inevitable that the ongoing and rapid changes in the physical environment of the marine Arctic will push components of the region’s existing social-ecological systems—small and large—beyond tipping points and into new regimes. Ongoing changes include warming, freshening, acidification, and alterations to food web structure. In anticipation we pose three distinct but interrelated challenges: (1) to explore existing connectivities within components of the marine system; (2) to seek indicators (if they exist) of approaching regime change through observation and modeling; and (3) to build functional resilience into existing systems through adaptation-oriented policy and to have in hand transformative options when tipping points are crossed and new development trajectories are required. Each of the above challenges is scale dependent, and each requires a much deeper understanding than we currently have of connectivity within existing systems and their response to external forcing. Here, we argue from a global perspective the need to understand the Arctic’s role in an increasingly nonlinear world; then describe emerging evidence from new observations on the connectivity of processes and system components from the Canada Basin and subarctic seas surrounding northern North America; and finally posit an approach founded in “resilience thinking” to allow northern residents living in small coastal communities to participate in the observation, adaption and—if necessary—transformation of the social-ecological system with which they live.  相似文献   
880.
Klijn F  de Bruijn KM  Knoop J  Kwadijk J 《Ambio》2012,41(2):180-192
Climate change and sea level rise urge low-lying countries to draft adaption policies. In this context, we assessed whether, to what extent and when the Netherlands’ current flood risk management policy may require a revision. By applying scenarios on climate change and socio-economic development and performing flood simulations, we established the past and future changes in flood probabilities, exposure and consequences until about 2050. We also questioned whether the present policy may be extended much longer, applying the concept of ‘policy tipping points’. Climate change was found to cause a significant increase of flood risk, but less than economic development does. We also established that the current flood risk management policy in the Netherlands can be continued for centuries when the sea level rise rate does not exceed 1.5 m per century. However, we also conclude that the present policy may not be the most attractive strategy, as it has some obvious flaws.  相似文献   
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