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111.
The Paris Agreement reached during the COP21 in December 2015 represents a timid step towards burden sharing in emission mitigation involving all countries. However, given the heterogeneity of countries and their relative differences in vulnerability to climate change damage and in mitigation costs, compensating schemes are required to reach an effective agreement. This paper investigates the role of the Green Climate Fund (GCF) as a potential compensating measure for both adaptation and mitigation actions under a global climate regime. A dynamic climate-economy computable general equilibrium model (GDynEP) is developed by including both a monetary valuation of climate change damage costs and two alternative methods to determine the allocation of GCF resources among receiving countries and between adaptation and mitigation contributions. Results show that, despite the high costs associated with the implementation of mitigation actions, most developing countries would face even higher costs in case of inaction. Furthermore, the preference of a country for an allocation method is strongly influenced by its characteristics and needs. Consequently, a main policy conclusion is to design country-specific sharing rules for GCF in order to maximize country participation in a global agreement. 相似文献
112.
113.
飞机作为航空产品,使用维护成本在全寿命周期费用中占据了相当大的比例。将使用维护成本折算为备件的采购和维修成本,在设计阶段通过基于备件的分析,分类计算在不同飞行强度下各种备件的采购和维修费用,从而确定飞机在满足用户需求的前提下所能执行的最经济的飞行强度。以某型飞机为例,提出了一种最经济飞行强度的计算方法,有助于在设计阶段规划飞机的使用和维护保障。 相似文献
114.
Faced with an intermittent but potent threat, animals exhibit behavior that allows them to balance foraging needs and avoid predators and over time, these behaviors can become hard-wired adaptations with both species trying to maximize their own fitness. In systems where both predator and prey share similar sensory modalities and cognitive abilities, such as with marine mammals, the dynamic nature of predator-prey interactions is poorly understood. The costs and benefits of these anti-predator adaptations need to be evaluated and quantified based on the dynamic engagement of predator and prey. Many theoretic models have addressed the complexity of predator-prey relationships, but few have translated into testable mechanistic models. In this study, we developed a spatially-explicit, geo-referenced, individual-based model of a prototypical adult dusky dolphin off Kaikoura, New Zealand facing a more powerful, yet infrequent predator, the killer whale. We were interested in two primary objectives, (1) to capture the varying behavioral game between a clever prey and clever predator based on our current understanding of the Kaikoura system, (2) to compare evolutionary costs vs. benefits (foraging time and number of predator encounters) for an adult non-maternal dusky dolphin at various levels of killer whale-avoidance behaviors and no avoidance rules. We conducted Monte Carlo simulations to address model performance and parametric uncertainty. Mantel tests revealed an 88% correlation (426 × 426 distance matrix, km2) between observed field sightings of dusky dolphins with model generated sightings for non-maternal adult dusky dolphin groups. Simulation results indicated that dusky dolphins incur a 2.7% loss in feeding time by evolving the anti-predator behavior of moving to and from the feeding grounds. Further, each evolutionary strategy we explored resulted in dolphins incurring an additional loss of foraging time. At low killer whale densities (appearing less than once every 3 days), each evolutionary strategy simulated converged towards the evolutionary cost of foraging, that is, the loss in foraging time approached the 2.7% loss experienced by evolving near shore-offshore movement behavior. However, the highest level of killer whale presence resulted in 38% decreases in foraging time. The biological significance of these losses potentially incurred by a dusky dolphin is dependent on various factors from dolphin group foraging behavior and individual energy needs to dolphin prey availability and behavior. 相似文献
115.
《Environmental Hazards》2013,12(5):414-433
ABSTRACTThe paper updates normalisation of the Insurance Council of Australia’s Disaster List in the light of debate about the contribution of global warming to the rising cost of natural disasters. Normalisation estimates losses from historical events in a common year, here ‘season’ 2017 defined as the 12-month period from 1 July 2017. The number and nominal cost of new residential dwellings are key normalising factors and post-1974 improvements in construction standards in tropical cyclone-prone parts of the country are explicitly allowed for. 94% of the normalised losses arise from weather-related perils – bushfires, tropical cyclones, floods and severe storms – with the 1999 Sydney hailstorm the most costly single event (AUD5.6 billion). When aggregated by season, there is no trend in normalised losses from weather-related perils; in other words, after we normalise for changes we know to have taken place, no residual signal remains to be explained by changes in the occurrence of extreme weather events, regardless of cause. In sum, the rising cost of natural disasters is being driven by where and how we chose to live and with more people living in vulnerable locations with more to lose, natural disasters remain an important problem irrespective of a warming climate. 相似文献
116.
The expansion of protected areas is a critical component of strategies to promote the continued existence of biodiversity (i.e., life at all levels of biological organization) as climate changes, but scientific, social, and economic uncertainties associated with climate change are some of the major obstacles preventing such expansion. New models of climate change and species distribution and new methods of conservation planning now make it possible to explore the uncertainties associated with climate changes and species responses. Yet few reliable estimates of the costs of expanding protected areas and methods for determining these costs exist, largely because of the many (and uncertain) determinants of these costs. We developed a cost-accounting model to estimate the range in costs of various options for expanding protected areas and to explore the variables that drive these costs. Model development was informed by an existing plan to expand protected areas in the Cape Floristic Region of South Africa to address species conservation under a scenario of climate change. The 50-year present value of total costs varied from US$260 million ($1077/ha) for an off-reserve option that involves agreements with landowners and no compensation of forgone production and associated revenue to $1020 million ($4228/ha) for an on-reserve option that involves land acquisition and protection. The costs of acquiring land or compensating landowners for forgone production and development opportunities were the major drivers of the total costs across all options because most of the area identified in the protected-area expansion plan consisted of urban and high-quality agricultural lands. Total costs were also affected by changes in protected area extent and discount rate. Model-generated outputs such as these may be useful for informing implementation strategies and the allocation of future efforts in monitoring, data collection, and model development. 相似文献
117.
Wayne B. Gray Ronald J. Shadbegian Chunbei Wang Merve Meral 《Journal of Environmental Economics and Management》2014
Any opinions and conclusions expressed herein are those of the author(s) and do not necessarily represent the views of the U.S. Census Bureau or the U.S. Environmental Protection Agency. All results have been reviewed to ensure that no confidential information is disclosed. We thank Wang Jin and Shital Sharma for excellent research assistance; we also thank Jim Davis at the Boston Research Data Center for his continued help, and Reed Walker and participants at the 2011 AERE Summer Conference and the Environmental Economics seminar at Harvard University?s Kennedy School for helpful comments. Any remaining errors are ours. 相似文献
118.
Energy efficiency plays an important role in reducing the carbon externality from buildings, but economic analyses of more efficient, green building have thus far ignored input costs. This paper finds that the average marginal cost of green-labeled construction projects is smaller than the value premiums documented in the literature. However, design fees, representing just a fraction of development costs but paid largely up-front, are significantly higher for green construction projects. These projects also take longer to complete. The results provide some insight into the market barriers and market failures that may explain the relatively slow adoption of otherwise economically rational green construction practices. 相似文献
119.
Solid Waste Treatment as a High-Priority and Low- Cost Alternative for Greenhouse Gas Mitigation 总被引:5,自引:0,他引:5
The increased concern about environmental problems caused by inadequate waste management, as well as the concern about global
warming, promotes actions toward a sustainable management of the organic fraction of the waste. Landfills, the most common
means to dispose of municipal solid waste (MSW), lead to the conversion of the organic waste to biogas, containing about 50%
methane, a very active greenhouse gas (GHG). One unit of methane has a global warming potential of 21 computed for a 100-year
horizon or 56 computed for 20 years. The waste sector in Israel contributes 13% of total greenhouse gases (GHG) emissions
for a time horizon of 100 years (for a time horizon of 20 years, the waste sector contribution equals to more than 25% of
total GHG emissions). The ultimate goal is to minimize the amount of methane (CH4) by converting it to CO2. This can be achieved by physicochemical means (e.g., landfill gas flare, incineration) or by biological processes (e.g.,
composting, anaerobic digestion). Since the waste in Israel has a high organic material content, it was found that the most
cost-effective means to treat the degradable organic components is by aerobic composting (investment of less than US$ 10 to
reduce emission of one ton CO2 equivalent per year). Another benefit of this technology is the ability to implement it within a short period. The suggested
approach, which should be implemented especially in developing countries, could reduce a significant amount of GHG at relatively
low cost and short time. The development of a national policy for proper waste treatment can be a significant means to abate
GHG emissions in the short term, enabling a gain in time to develop other means for the long run. In addition, the use of
CO2 quotas will credit the waste sector and will promote profitable proper waste management. 相似文献
120.
Michael B. Sonnen Larry C. Davis 《Journal of the American Water Resources Association》1979,15(2):404-419
ABSTRACT: Two analytical methods are presented and demonstrated for evaluating the monetary and nonmonetary benefits of wild rivers. In the traditional benefit-cost context special techniques are required to show that any wild river is worthy of preservation. The methods presented allow for the possibility of low development levels in river basins to be optimal, although advanced development can also be shown to be most efficient in some circumstances. That is, the methods are not directed to the wild condition only but to the entire spectrum of development possibilities. The applications of the methods to two adjacent subbasins in the State of Washington each showed that the currently undeveloped basin should be left in its wild condition, while the partially developed basin next door should be developed even more fully. 相似文献