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51.
To some degree it is unfair to evaluate a post-disaster housing program as to its effectiveness in decreasing vulnerability and preventing future disasters. As Burton states, "With rare exceptions, administrators and techniques have been trained to cope with disaster rather than to prevent it" [reference (2), p.197]. These were certainly not goals articulated by the agency responsible for constructing housing after Fifi. However, the authors feel that failure to evaluate specific projects by persons knowledgeable of the projects functioning, will only forestall the shift which Cuny calls for, "… from disaster response to disaster mitigation and prevention" [reference (4), p.123). In doing this we hope to add some specific case study data to the growing literature on disaster mitigation and prevention. Disaster vulnerability in Honduras is overwhelmingly related to flooding. More crucial than the materials and construction of housing is the issue of siting. If appropriately sited, houses made of bajarique, wood, or concrete block are able to withstand the heavy rains associated with a hurricane. Regarding the siting of the projects, the Honduras Project clearly has one positive and one negative accomplishment in the cases of Santa Rica and Flores, respectively. San Jose is less clear but is certainly a much safer site than those formerly occupied by the residents, in that there is no danger of flooding. The present site was not flooded during Fifi nor did it experience mudslides. However, the future is not so clear regarding the latter. Within the village proper a large amount of vegetation has been added which will tend to stabilise the soil on the steeper slopes. The streets, however, are seriously eroded and probably can not be maintained for vehicle usage, which does not pose a serious problem to the residents as none possess automobiles or trucks. One large gully bisects the village and receives run-off from the adjacent hills. It has been expanding, which would suggest that the slopes above the village could prove problematic in case of a Fifi-sized storm. Flores is located on a very poor site in reference to prevention and mitigation. It is located in a portion of the Sula Valley which is prone to flooding and, as mentioned before, was inundated by over 2m of water during hurricane Fifi. No prevention techniques were possible by NAEA/HEA and the houses were built on earthen mounds barely adequate to keep water out during the rainy season. The nearby dike which could possibly provide protection is non-functional due to poor maintainance. Given a storm of Fifi's magnitude, or possibly smaller, this site will again be flooded. Santa Rica is clearly well sited concerning flooding: it did not experience flooding during Fifi and is not flood prone. However, houses did experience some wall damage due to earthquakes following and associated with the Guatemalan quake of 1976. Due to the size and nature of the latter much "re-adjustment" occurred in the neighbouring fault system; however, damage to the houses was all superficial. We feel the residents were vocal about their concern due to the severity of the Guatemalan disaster and their lack of experience with concrete block houses. That the two sites (particularly Flores and partially San Jose) are vulnerable to future disasters cannot be considered solely the fault of an outside agency without local knowledge and understanding. In the engineering report issued during the construction it was explicitly stated that in Flores, "Future flooding remains a danger," [reference (6), p.49]. The future residents of Flores had gained access to the land from the National Agrarian Institute and were anxious to receive assistance in building homes. In fact, CARE, which had previously given these people tin roofing for houses, was threatening to take it back since the people had not yet started building. NAEA/HEA were responding to people in a rather desperate situation. But, on the other hand, they were responding to people who had been promised (not given) land by an agency of the Honduran national government which would be cognizant of the potential flooding at this site. Likewise, in San Jose, where mudslides and erosion remain a threat, the land was provided by a local government agency, the municipality. Although our goal in this discussion has not been to establish blame, we feel it imperative to mention the sequence of events that resulted in the questionable siting of Flores and San Jose. It is very easy and often accurate to place blame on outsiders who lack sophistication and knowledge about such matters. In this case local input did not result in post-disaster planning that is actually precautionary. This, we feel, illustrates the extreme complexity of cross-cultural aid, especially in the post-disaster period. It also points to the need for precautionary planning with reference to permanent post-disaster reconstruction. 相似文献
52.
ERIC N. POWELL JOHN M. KLINCK EILEEN E. HOFMANN MARGARET A. McMANUS 《Environmental management》2003,31(1):0100-0121
A hydrodynamic–oyster population model was developed to assess the effect of changes in freshwater inflow on oyster populations
in Galveston Bay, Texas, USA. The population model includes the effects of environmental conditions, predators, and the oyster
parasite, Perkinsus marinus, on oyster populations. The hydrodynamic model includes the effects of wind stress, river runoff, tides, and oceanic exchange
on the circulation of the bay. Simulations were run for low, mean, and high freshwater inflow conditions under the present
(1993) hydrology and predicted hydrologies for 2024 and 2049 that include both changes in total freshwater inflow and diversions
of freshwater from one primary drainage basin to another.
Freshwater diversion to supply the Houston metropolitan area is predicted to negatively impact oyster production in Galveston
Bay. Fecundity and larval survivorship both decline. Mortality from Perkinsus marinus increases, but to a lesser extent. A larger negative impact in 2049 relative to 2024 originates from the larger drop in fecundity
under that hydrology. Changes in recruitment and mortality, resulting in lowered oyster abundance, occur because the bay volume
available for mixing freshwater input from the San Jacinto and Buffalo Bayou drainage basins that drain metropolitan Houston
is small in comparison to the volume of Trinity Bay that presently receives the bulk of the bay's freshwater inflow. A smaller
volume for mixing results in salinities that decline more rapidly and to a greater extent under conditions of high freshwater
discharge.
Thus, the decline in oyster abundance results from a disequilibrium between geography and salinity brought about by freshwater
diversion. Although the bay hydrology shifts, available hard substrate does not. The simulations stress the fact that it is
not just the well-appreciated reduction in freshwater inflow that can result in decreased oyster production. Changing the
location of freshwater inflow can also significantly impact the bay environment, even if the total amount of freshwater inflow
does not change. 相似文献
53.
N. K. Woodfield J. W. S. Longhurst C. I. Beattie D. P. H. Laxen 《Journal of Environmental Planning and Management》2003,46(1):49-64
The UK National Air Quality Strategy has required local authorities to review and assess air quality in their area of jurisdiction and determine locations in their areas where concentrations of specific air quality pollutants are predicted to exceed national air quality objectives in the future. Statutory air quality management areas (AQMAs) are designated where air quality is predicted to be above specified objective concentrations by specific target dates, and statutory air quality action plans will be necessary to improve the local air quality within these areas. Over 124 local authorities in England (including London), Wales and Scotland anticipate declaring AQMAs following the conclusion of the statutory air quality review and assessment process. However, other influences are being exerted on the local air quality management process and AQMA decision-making processes. Such influences include regional and sub- regional collaborative working between local authorities and government agencies and wider political decision-making processes. Some regions of Great Britain (encompassing England (including London), Scotland and Wales) anticipate many AQMA designations, whilst other regions are not anticipating any such designations despite apparently similar air quality circumstances. Evidence for regional or sub-regional variations in the locations of anticipated AQMAs are examined through an evaluation of the outcomes of the scientific review and assessment process undertaken by local authorities declaring AQMAs, and through a local authority survey to identify influences on decision-making processes at a level above that of the local authority. Regional variation is reported in the type of pollutant causing AQMAs to be declared, in the numbers of AQMAs in regions and in the spatial distribution of AQMAs across Great Britain. 相似文献
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56.
Until now no structured methodology existed for attuning environmental considerations to the business strategy of companies. The Environmental Competence Centre of Philips Sound & Vision in The Netherlands has developed and tested a methodology for this purpose. This methodology, called Selection of STRrategic Environmen Tal CHallenges (STRETCH), has proven to lead to promising results and should therefore be actively promoted. In this article, the authors show how the application of STRETCH provides the possibility of meeting three main objectives: First, focusing on the incorporation of environmental aspects into the company's business strategy can elicit innovations that may enhance the competitive position of the company by cost reduction and/or higher market shares. Second, the environmental opportunities and threats to be expected in the future can be anticipated in an earlier phase. Through this proactive approach a company can avoid external criticism and take the lead in environmental priority setting. Third, by applying the STRETCH methodology even higher eco-efficiencies are expected to be reached than through incremental, step-by-step environmental improvements. 相似文献
57.
A pedagogic problem in forestry and landscape management is to visualize future landscape effects of forest growth and current management activities in the forest. This paper presents a method for forecasting digital image projections of forest landscape dynamics. Static nonlinear regression functions estimate the digital numbers in a Landsat Thematic Mapper image. Regressors used are forest stand variables. By estimating the future forest stand data, based on intermediate treatment and growth, future satellite digital images are created. In a case study example, the future landscape of a forest block in the province of Västernorrland, Sweden, is projected to demonstrate the application of this visualization technique. 相似文献
58.
Summary Quantitative studies on the biomethanation processes using a different biomass (goat dung, cow dung, buffalo dung, piggery waste, poultry waste and sewage) alone or in combination have been made. The dung samples have been found to be an efficient producer of biogas at a 1:2 dilution. Better yields of biogas are obtained in combination with other biomasses rather than when used alone. Judicious mixing of biomasses, however, is important. Competitive biomethanation of a biomass by other biomasses as a source for a wild population of microbes has been studied in vials using a cross-inoculation technique, i.e. using inoculum of one biomass on different sterile biomasses. The results show that the microbes are very specific and usually non-adaptive. Each inoculum outclasses others in using its natural biomass for methanation but reacts poorly when inoculated to other alien biomasses. Buffalo dung is to some extent adaptive in nature.Professor S.C. Lahiri is the senior author of this paper and he is ex-Head of the Department of Chemistry at the University of Kalyani where Nilanjan Chakravorty is a research fellow. Dr G.M. Sarkar is a senior lecturer in the Department of Botany at Ranaghat College, Ranaghat, Nadia, West Bengal, India. 相似文献
59.
This paper assesses the status of coastal zones in the context of expected climate change and its related impacts, as well as current and future socioeconomic pressures and impacts. It is argued that external stresses and shocks relating to sea-level rise and other changes will tend to exacerbate existing environmental pressures and damage in coastal zones. Coastal zones are under increasing stress because of an interrelated set of planning failures including information, economic market, and policy intervention failures. Moves towards integrated coastal zone management are urgently required to guide the coevolution of natural and human systems. Overtly technocentric claims that assessments of vulnerability undertaken to date are overestimates of likely future damages from global warming are premature. While it is the case that forecasts of sea-level rise have been scaled down, much uncertainty remains over, for example, combined storm, sea surge, and other events. In any case, within the socioeconomic analyses of the problem, resource valuations have been at best only partial and have failed to incorporate sensitivity analysis in terms of the discount rates utilized. This would indicate an underestimation of potential damage costs. Overall, a precautionary approach is justified based on the need to act ahead of adequate information acquisition, economically efficient resource pricing and proactive coastal planning. 相似文献
60.