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131.
132.
Adaptation is nowrecognized as an inevitable component ofthe overall climate change responsestrategy. For a developing region likesub-Saharan Africa with low greenhouse gasemissions and high vulnerability to theimpacts of climate change, the importanceof adaptation in climate change policy iseven more fundamental. This paper examined alook at the adaptational preparedness ofthe sub-Saharan African region to climatechange. Clearly evident in theenvironmental strategy and developmentfocus of these countries is lack ofrecognition of the need to adapt, poorincentive to adapt and low capacity toadapt to climate change. This furtherexacerbates their vulnerability and hasimplications for the global climate changeresponse strategy. Unfortunately, fewattempts have been made to understand thestructural reasons underlying the pervasivepattern of adaptational unpreparedness inthe region, neither has there been acomprehensive and systematic analysis ofhow to remedy this problem. This paper is acontribution in this regard. It alsohighlights the factors to whichinternational community need to payattention, if it truly wishes to make itsefforts at adaptation more global inscope. 相似文献
133.
中国南方喀斯特地区面积大,自然资源丰富,生态环境脆弱,在世界喀斯特地区中极具代表性。文章依据中国南方喀斯特地区独特的自然特征和社会、经济功能,借助申报自然遗产机遇,为实现该区人口、资源、环境与社会的可持续发展,提出了一系列针对中国南方喀斯特地区的保护策略及措施。 相似文献
134.
本文详细的论述了地震灾害效应,并给出了地震灾害防御对策的准确概念。在总结中国近二十年地震灾害防御对策的基础上,给出了今后我国地震灾害防御对策的发展趋势,对于我国今后开展震害防御工作具有一定意义。 相似文献
135.
Fuelwood plays an important role in the rural economy of the developing countries of Asia and Africa. Optimizing energy fixation
in forest trees through high density energy plantations (HDEP), gasification of wood, and conversion of forest tree biomass,
are some of the potential areas whereby additional research and development input for efficient management of atmospheric
carbon in our energy system can be incorporated. For example, the photosynthetic efficiency of forest trees is rarely above
0.5%, which on the basis of theoretical considerations can be increased by up to 6.6%. Thus there is an ample scope to improve
the efficiency up to 1%, which amounts to doubling of the productivity of the forests.
Recent policy changes and experiences with wood-based bio-energy programmes in several countries indicate that woodfuels may
become increasingly attractive as industrial energy sources. Use of biodiesel and the formulation of a project for undertaking
13.4 million ha of Jatropha plantations in India highlight the seriousness with which the Government of India is promoting carbon neutral energy plantations.
The cost of establishment of plantations primarily for fuel production and its conversion to energy are major deterrents in
this pursuit. Some of the issues in developing countries, like low productivity on marginal lands, degraded forest lands,
and unorganized units for biomass energy conversion, result in cost escalation as compared to other energy sources. This paper
revisits the scope for raising energy plantations, a comparison of the direct and indirect mitigation potential uses of plantations
as an adaptation strategy through reforestation and afforestation projects for climate change mitigation and socio-economic
issues to make this venture feasible in developing countries. 相似文献
136.
137.
Dhazn Gillig Bruce A. McCarl Ronald D. Sands 《Mitigation and Adaptation Strategies for Global Change》2004,9(3):241-259
An econometrically estimated family ofresponse functions is developed forcharacterizing potential responses togreenhouse gas mitigation policies by theagriculture and forestry sectors in theU.S. The response functions are estimatedbased on results of anagricultural/forestry sector model. Theyprovide estimates of sequestration andemission reductions in forestry andagriculture along with levels of sectoralproduction, prices, welfare, andenvironmental attributes given a carbonprice, levels of demand for agriculturalgoods, and the energy price. Sixalternative mitigation policiesrepresenting types of greenhouse gasoffsets allowed are considered. Resultsindicate that the largest quantity ofgreenhouse gas offset consistently appearswith the mitigation policy that pays forall opportunities. Restricting carbonpayments (emission tax or sequestrationsubsidy) only to aff/deforestation or onlyto agricultural sequestration substantiallyreduces potential mitigation. Highercarbon prices lead to more sequestration,less emissions, reduced consumer and totalwelfare, improved environmental indicatorsand increased producer welfare. 相似文献
138.
李安民 《湖南环境生物职业技术学院学报》2001,(4)
在社会主义市场经济条件下,为什么要大力发展高等职业教育?文章认为,发展高等职业是市场经济发展和科教兴国的客观要求,并通过对高职教育的定位分析,阐明了发展高职教育的重要性.文章从高等教育的特点和“三改一补”的发展途征两方面论述了高职教育的发展方向. 相似文献
139.
140.
Tamara Fraizer 《Behavioral ecology and sociobiology》1997,41(6):423-434
I develop a state-based dynamic model of behavior to demonstrate that size-dependent differences in temperature tolerances
are not necessary to account for the activity of small male digger wasps late in the day. In the model, males defend or patrol
the nesting area, wait near nests, or feed away from the nesting area depending on time of day, energy reserves and size rank.
I assume a large male competitive advantage, so mating opportunities decrease with size rank for territorial or patrolling
males and are rare for all waiting males; the costs of patrolling or defense are higher than the costs of waiting. If energy
reserves of all males are initially small, all males alternate feeding and territorial or patrolling behavior. If energy reserves
are initially large, large males patrol or maintain territories until they risk starvation and leave the area to feed. At
this time, smaller males that have conserved their resources by waiting and feeding may defend territories or patrol. I simulate
the behavior of three populations representing two species of Microbembex by assuming large initial energy reserves for populations in which males were territorial and small initial reserves for
populations in which males patrolled, and then convert the predicted time of activity to temperature using local regressions
from field studies. Temporal patterns in the activity of large and small males were similar to those actually observed, and
relationships between size and temperature predicted by the model corresponded to most observations and were sometimes positive.
Thus, the delayed activity of smaller males does not correspond to activity at higher temperatures and is probably not attributable
to size-dependent thermal tolerances, but may represent a temporal displacement of mating activity due to intra-sexual competition
and mediated by energetics. The model makes testable predictions on the timing of feeding and depletion of energy reserves
in relation to size and initial energy state, and suggests how differences among species may influence the temporal and spatial
organization of male mating behavior.
Received: 27 February 1997 / Accepted after revision: 26 July 1997 相似文献