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521.
Billy Christmas 《环境政策》2017,26(3):502-520
Cost–benefit analysis has been criticised on the grounds that it cannot compute the value of environmental goods whose value constitutively defies monetary valuation. Two forms of incommensurability make monetary valuation problematic: constitutive incommensurability and quantitative incommensurability. These pose a threat only to shadow pricing, and not the formation of prices in an actual market. Where property rights to environmental goods are appropriately assigned, the prices that form reflect the actual uses persons put them to, given their value commitments. In a real market, the formation of prices does not depend upon the assignment of cardinal values via monetary valuation; rather, the formation of prices is a side effect of the way in which environmental goods are used. A property right gives one the right to reject terms of exchange one deems inappropriate. Where sale of an environmental good is deemed inappropriate, it is kept out of the cash nexus. Incommensurability therefore precludes cost–benefit analysis, but not markets in environmental goods where property rights are appropriately allocated. 相似文献
522.
Dafna M. DiSegni Menashe Bitan Dov Zviely 《Journal of Environmental Planning and Management》2017,60(11):2056-2070
Marine constructions are highly vulnerable to climate change and sea-level rise (SLR), leading to increased risk rates of destruction and the potential closure of ports, harbors, and marinas along the coast. We present a cost-adjustment analysis for such constructions along the south-eastern Mediterranean coast, which takes into account the physical characteristics of the constructions, and environmental uncertainty factors. At 0.5 m SLR, the estimated adjustment cost is USD 280 million, and at 1 m SLR, the estimated cost is USD 505 million. These costs are equivalent to 0.091% and 0.165% of the Israeli gross domestic production, respectively. Although high, these adjustment costs are lower than the costs of future damage that will accrue if we fail to act. This implies that the adaptation-policy approach to controlling for the risk of SLR will provide benefits to the economic marine sectors and the public at large. 相似文献
523.
Mónica Rodríguez-Freire Rafael Crecente-Maseda 《Environmental Modeling and Assessment》2008,13(1):35-51
In view of the extensive information available on wolf ecology and habitat suitability, and on the fragmentation of wolf populations
by motorways and similar infrastructures, a key factor in their conservation, the aim of the present study was to model the
directional connectivity of wolf populations in the region of Galicia in northwest Spain, and to quantify anthropogenic effects
on wolf dispersal patterns. To this end, we map the probability of wolf movement by means of known relationships between wolf
movement and anthropogenic, vegetation and topographic factors. The relative importance of each factor was quantified by sensitivity
analyses. Three types of cost surface were constructed: (a) isotropic surfaces, (b) anisotropic cost surfaces taking into
account terrain slope effects in the movement, and (c) surfaces obtained by combining the isotropic and anisotropic surfaces.
The results obtained by approaches (a) and (c) indicate that one of the region’s motorways (the AP-9) probably acts as a significant
barrier to wolf movement, possibly isolating two subpopulations, while the remaining motorways probably do not have major
effects on dispersal. Estimation of lowest-cost routes for wolf displacement allowed identification of areas critical for
connectivity, in which it would be of interest to perform detailed studies with more precise input data on motorway course
and the location of drainage channels and underpasses, etc. (these being the factors identified by sensitivity analysis to
be those with the most marked effects on the cost surfaces). The visualization of connectivity enabled by this approach will
allow wolf management and conservation efforts to be focused on critical areas: such efforts might include measures aimed
to encourage wolf dispersal through areas in which conflict with human activity is minimized, thus contributing positively
to the management of a socially conflictive species. Finally, evaluation of the different cost surfaces suggests that it would
be of interest to introduce two modifications to the anisotropic algorithm, to allow the user to weigh the importance of the
different input factors, and to allow the inclusion of more than one anisotropic factor in the model. 相似文献
524.
D. Murdiyarso 《Environmental monitoring and assessment》2000,61(1):123-131
The impacts of climate change on potential rice production in Asia are reviewed in the light of the adaptation to climatic variability and change. Collaborative studies carried out by IRRI and US-EPA reported that using process-based crop simulation models increasing temperature may decrease rice potential yield up to 7.4% per degree increment of temperature. When climate scenarios predicted by GCMs were applied it was demonstrated that rice production in Asia may decline by 3.8% under the climates of the next century. Moreover, changes in rainfall pattern and distribution were also found suggesting the possible shift of agricultural lands in the region. The studies however have not taken the impacts of climatic variability into account, which often produce extreme events like that caused by monsoons and El Niño. Shifts in rice-growing areas are likely to be constrained by land-use changes occurring for other developmental reasons, which may force greater cultivation of marginal lands and further deforestation. This should be taken into account and lead to more integrated assessment, especially in developing countries where land-use change is more a top-down policy rather than farmers' decision. A key question is: To what extent will improving the ability of societies to cope with current climatic variability through changing design of agricultural systems and practices help the same societies cope with the likely changes in climate? 相似文献
525.
Biodiversity monitoring surveys are rarely optimised statistically before being initiated. Here, we optimised the monitoring
of plants in a temperate forest. The total inventory cost, the number and size of quadrats were optimised to detect a 10%
change in species richness over 5 years with α = β = 0.05, using data from ongoing long-term floristic monitoring programs. The procedure showed that the inventory cost would
be ca 15% lower using 100-, 200-m2 quadrats instead of 300- or 400-m2 quadrats. Despite the cost associated with the optimisation (e.g. gathering preliminary data) and the imprecise estimates
(due to the typically small sample size of the pilot studies), optimisation would often be a better option than expert opinion
when designing a monitoring survey. 相似文献
526.
527.
Applying the relational analysis in the Grey System Theory and Method, the comprehensive evaluation on five pesticide pollution controlling techniques in the vegetable production has been made and a comprehensive profit (cp–comprehensive cost (cc) evaluation system (composed of 15 comprehensive cost indices and 14 comprehensive profit indices) has been established, with a index optimization matrix of comprehensive cost indices and comprehensive profit indices obtained and a ratio model of comprehensive cost to comprehensive profit (Rcc/cp) built. Results show that the Rcc/cp value of vegetables intercropping soybeans in insect-proof thin film greenhouses is the smallest and the Rcc/cp value of vegetables intercropping taros in insect-proof net greenhouses, pheromones in insect-proof thin film greenhouses, pheromones in insect-proof thin film greenhouses and ground planting (only using chemical pesticide for insect-proof without covering materials and synthetic sex pheromone) other four techniques are 0.6268, 0.6393, 0.6407, 0.9809 respectively. In accordance with the Rcc/cp value, vegetables intercropping soybeans in insect-proof thin film greenhouses can be the most optimized pesticide pollution controlling technique in the vegetable growing. 相似文献
528.
我国城市污水处理的有效措施 总被引:16,自引:0,他引:16
我国水环境污染和水资源短缺,促进了污水处理厂的建设,而污水处理工艺在很大程度上决定了污水处理厂的投资、基建费用、用地和运行管理费用。文章介绍了我国有污水处理厂的工艺、投资和运行费用。结合我国的基本国情,提出了建立经济有效的处理工艺的措施。 相似文献
529.
自然资源可持续利用的实现,需要有效的制度保证.目前,主流的观点是支持政府管制.但是,本文从一个实例出发,证明了由自治组织内部成员间相互监督而形成的剔出机制,不仅使得违规成本最大化,而且剔出违规成员增加了其他成员的监督收益,所以有效地增强了监督效用.从而使得独立的自治组织内部监督成本低于政府的规制成本.同时本文阐明了在剔出机制下,自治组织对自然资源可持续利用的有效性以及最优规模边界问题.自治组织的规模只有小于该最优规模边界值时,成员间的相互监督机制才能有效;当自治组织的成员数大于该边界时,可先建立规模较小的组织,在此基础上进一步构建较大的组织,最终形成网络结构.同时,本文进一步证明了在自然资源量一定的情况下,自治组织可通过品牌授权带来非资源量的增值,这对促进自然资源可持续利用尤其重要.在此理论研究的基础上,本文对对我国现实的自治组织或自治协会提出了相应的建议. 相似文献
530.
华北平原冬小麦-夏玉米种植模式碳足迹研究 总被引:17,自引:0,他引:17
农业碳足迹理论可以系统评价农业生产过程中人为因素引起的碳排放,是构建低碳农业的理论基础,对实现低碳农业其有重要的指导意义.为探明农业生产中的碳足迹,本文基于河北吴桥县农户生产调查数据,利用农业碳足迹理论及研究方法,评价了华北平原冬小麦-夏玉米两熟种植模式的碳足迹.结果表明:冬小麦-夏玉米种植模式碳足迹的大小为1 737.37±337.02 kgCe/hm2·a,生产1 kg粮食的碳成本是0.12±0.03 kgCe,其中冬小麦的碳足迹是1 101.31±251.91 kgCe/hm2·a,小麦的碳成本是0.16±0.04kgCe/kg,夏玉米的碳足迹是636.06±163.90 kgCe/hm2·a,玉米的碳成本是0.08±0.02 kgCe/kg.冬小麦-夏玉米种植模式碳足迹的组成中,化肥占总量的61.76%,电能占25.03%,柴油占7.44%,种子占4.75%,农药占1.02%.同时,发现N肥的施用量和电能消耗量均与碳足迹有正相关性,种植规模与碳成本有负相关性.因此,构建节肥、节水及规模化的低碳种植模式是实现华北平原农业节能减排的重要途径. 相似文献