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261.
In this paper, the role of nutrient transports between marine basins is investigated for cost-effective solutions to predetermined marine basin targets. The interdependent advective nutrient transports as well as retentions among the seven major marine basins of the Baltic Sea are described by input-output analysis. This is in contrast to prior economic studies of transboundary water pollution that include only direct transport between the basins. The analytical results show that the difference in impacts between transport specifications depends mainly on the openness of the basins, that is, their transports with other basins. The application on Baltic Sea shows significant differences in costs and policy design between the nutrient transport specifications. The reason is that the Sea is characterized by long water and nutrient residence times, so relatively large part of nutrients are transported among basins. 相似文献
262.
G. David Puttock 《Environmental management》1985,9(1):83-88
The establishment of forest reserves for the benefit of other resources and other land uses in areas where timber harvesting is taking place constitutes a significant withdrawal of wood fiber annually in Ontario.This article reports on a case study carried out on a representative forest area in northern Ontario where the primary land use is timber extraction. The results projected to the whole province show that the direct cost to the provincial economy of removing these forest lands from timber production is of the order of $2.5 million annually. 相似文献
263.
ABSTRACT: The proper use of input-output for estimating regional benefits and costs is described for instances where project outputs go to final or intermediate demand. How that estimation is affected by the method used to value the primary project benefits and by the sector content of the input-output model compared to the primary sector affected are discussed as are points of terminological confusion between the two methods. 相似文献
264.
Terry W. Rothermel Milton S. Sachs Frank O'Shaughnessy 《Journal of the American Water Resources Association》1971,7(4):867-877
ABSTRACT The Office of Saline Water, which has federal responsibility for developing low-cost, saline sources of fresh water, has recognized the need for an improved method of forecasting the future potential of desalting in this country. The magnitude of the role of desalting will influence the plans of federal, state, and local water resource agencies and the research and development programs of manufacturers. A dynamic simulation model has been developed by Arthur D. Little, Inc. under contract by OSW to translate relevant factors of water supply and demand into a forecast of desalting potential. The model projects the needs for desalting in 20 hydrologic regions of the U.S. Model performance has thus far been demonstrated by the development of a forecast and a battery of related sensitivity tests. Current results indicate the following potential desalting capacities: 225 MGD in 1980; 2,250 MGD in 2000; and 7,000 MGD in 2020. Significant improvements in desalting economics promise to increase these potentials by a factor of four or five by 2000-2020. Model inputs and results are continuing to be refined. When completed, OSW will have a dynamic tool with which to guide its R&D program. 相似文献
265.
Gordon R. Sloggett Harry P. Mapp 《Journal of the American Water Resources Association》1984,20(2):229-233
ABSTRACT: Irrigation costs are rising rapidly on the 32 million acres irrigated with ground water. Ground water levels are declining under about 15 million of those acres adding to increased costs. However, from 1975 to 1982, 75 to 80 percent of increased ground water irrigation costs were due to higher nominal energy prices and interest rates. In real dollars, adjusted for inflation, these costs have risen faster than other irrigation costs and the real rise in commodity prices has been very small. A continuation of rapidly rising costs and slowly rising prices will shorten the economic life of those aquifers experiencing declining water levels. That same condition of prices and costs place all ground water irrigators in a disadvantaged position compared to nonirrigators and could cause a decline in ground water irrigation. 相似文献
266.
The impact of measurement assumptions upon individual travel cost estimates of consumer surplus: a GIS analysis 总被引:1,自引:0,他引:1
I. J. Bateman J. S. Brainard A. A. Lovett G. D. Garrod 《Regional Environmental Change》1999,1(1):24-30
The individual travel cost method is one of the most commonly applied approaches to estimating the recreational value (or
`consumer surplus') of open-access sites where the visitor does not have to pay an entrance charge for using the area. This
paper presents a simple application of the method conducted using geographical information system (GIS) software. This approach
permits analysis of the impact of various, commonly used, assumptions concerning the definition of visitor outset origins
and routing to recreation sites. Results suggest that varying these assumptions can lead to substantial impacts upon estimates
of consumer surplus to the extent that previously published studies may be subject to substantial error.
Received: 24 February 1999 · Accepted: 9 June 1999 相似文献
267.
佛山市顺德区工业VOCs污染问题突出,以中小企业为主的家具行业排放是第二大来源(17%),因此,顺德区率先在广东省开展了家具行业VOCs排污权交易试点工作.本文以区内木质家具行业为例,研究了排污权交易定价方法,得到VOCs平均污染治理成本(5363.26元·t~(-1)·a~(-1))并将其作为排污权交易的初始价格,之后运用多级模糊综合评价法计算的地区调整系数(γ=1.47)进行修正,得到最终参考交易价格(7883.99元·t~(-1)·a~(-1)).该价格与2016年交易底价(8000元·t~(-1)·a~(-1))偏差较小(1.45%).本文还开发了内置核心算法的挥发性有机物排污权交易辅助定价工具,综合利用数据库中企业基本信息、挥发性有机物排放数据等,为排污权交易定价提供辅助决策服务. 相似文献
268.
269.
Optimal hardwood tree planting and forest reclamation policy on reclaimed surface mine lands in the Appalachian coal region 总被引:4,自引:0,他引:4
We study the optimal hardwood tree planting decision on reclaimed surface coal mines in the Appalachian region using a mine operator-focused, expected cost model that recognizes costs of preparing the site for tree planting, unit costs of planting seedlings, and opportunity costs of reforestation treatments and the performance bond. We also consider the possibility of failed initial attempts by incorporating the probability of reforestation success, based on empirical seedling ,survival rates and regulated tree survival standards, as well as fixed and unit costs of returning for additional planting. Optimal planting levels from 319 to 780 trees per acre and expected costs from $1049 to $2338 were found using simulations over a range of unit planting costs, fixed costs of replanting, tree survival standards, and interest rates. Further simulations compared optimal planting across un-weathered gray sandstone and weathered brown sandstone substrate materials, finding gray sandstone to be associated with lower expected costs. We conclude that optimal planting density and expected reforestation cost are sensitive to economic parameters, regulations, and planting substrate materials; and those policies influencing these factors may have substantial impact on reforestation outcomes and the choice of post-mining land use by mine operators. Our study provides a framework for understanding forest reclamation decisions that incorporates incentives faced by the mine operators who develop and implement the plans for mine reclamation, including forestry. 相似文献