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101.
Measurement of the quality and quantity of wildlife habitat is a necessity in planning and analyzing water resource projects. A methodology that provides a means of examining the following major components of habitat quality is proposed: (1) the quantity of land uses, (2) the degree of interspersion of land use, aand (3) the stage of land management and vegetative types. The model can be calibrated to a specific region by experienced wildlife biologists and applied by field technicians using aerial photographs and field evaluation of randomly located points. Biologists familiar with a region develop transformation curves relating variables that represent the above three major components to standardizing factors that range from 0 to 1; these transformation curves reflect the sensitivity of wildlife populations to determinants of habitat quality. The methodology also provides the means for biologists to weigh each components as to its relative importance to the wildlife group or species. A weighted geometric mean of the components provides an indication of the overall quality of the habitat. Changes in the habitat components that may occur because of alternative project actions can be used to evaluate the effectiveness of the alternatives. The change in the index of habitat quality will indicate the need for mitigation in water resource projects. The system then can be used to identify areas for mitigation and the effects of mitigating measures.  相似文献   
102.
ABSTRACT: The principal objective of this study was to investigate the long-term, temporal effect of channel modification in the diversity of macroinvertebrates. Correlation analyses suggest that aquatic macroinvertebrate communities stabilize shortly after channel modification. This conclusion is based on correlation analyses including five widely accepted diversity indices for stream reaches that have undergone channel work from less than 1 year to more than 30 years prior to the study.  相似文献   
103.
The Rocky Mountain Arsenal (RMA) in Adams County, Colorado has been identified as a priority site on the Superfund National Priority List. The Program Manager's Office of RMA announced in early 1990 its intention to implement installation of a state-of-the-art incineration plant to treat the most complex and controversial waste stream on the site. Established in 1942, RMA served as an Army manufacturing center for chemical agents such as mustard gas, white phosphorus, napalm, and GB nerve agent. Parts of the site were also leased to Shell Oil Company, which manufactured pesticides and other agricultural chemicals at this location between 1952 and 1982. To support these activities, the Army operated a ninety-three-acre surface impoundment called Basin F for collection and evaporation of chemical wastewaters. As a result of the wide variety of wastes received and concentrated at Basin F and early treatment attempts, its contents became one of the most unusual chemical cocktails known to man. By the time a formal interim response action for remediation was initiated in 1985, the composition of the Basin consisted of a multi-phase fluid and sludge, including super-saturated levels of inorganic salts; 30 percent or more organics such as pesticides, military agent by-products, degradation products, and solvents; high levels of ammonia compounds and bound nitrogen; and percent levels of copper, arsenic, and other metals. Selection of a remedial alternative involved twelve years of characterizationstudies and eleven years of treatability testing programs encompassing the universe of containment; encapsulation; stabilization; component separation; and thermal, electrical, chemical, and biological degradation technologies. The program resulted in the selection of a state-of-the-art down-fired liquid incinerator for destruction of aqueous organic contaminants in metallic salt matrices. The treatability demonstration, and the technical justification for selection of the T-Thermal submerged quench incinerator for this application, is the subject of this article.  相似文献   
104.
We observe a paradigm shift toward collaborative, multi‐level (from local to global) water management and suggestions for scale‐related design principles in the literature. Decision‐support tools are needed that can help achieve scale design principles. Mediated modeling (MM) refers to model building with people, rather than for people. This tool belongs to a family of participatory, systems oriented tools. This article explores their suitability for addressing challenges and principles that arise at multiple‐scales. MM can promote the understanding of cross‐level and cross‐scale links, creating salient, credible, and legitimate knowledge and encouraging boundary functions. Prerequisites for successful MM processes include an openness and willingness to collaborative learning. As new “meso‐level” institutions emerge to address complex challenges in water management collaboratively, tools like MM may play an important role in structuring dialogues, developing adaptive management capacity and advance an ecosystem services approach.  相似文献   
105.
A field experiment was conducted to determine the effect of fly ash from a coal combustion electric power facility on soil acidity in a cotton (Gossypium hirsutum L.) field. Fresh fly ash was applied to a Bosket fine sandy loam (fine-loamy, mixed, thermic Mollic Hapludalf) soil with an initial soil pH(salt) of 4.8. The fly ash was equivalent to 42 g kg(-1) calcium carbonate with 97% passing through a 60 mesh (U.S. standard) sieve. Fly ash was applied one day before cotton planting in 1999 at 0, 3.4, 6.7, and 10.1 Mg ha(-1). No fly ash was applied in 2000. Within 60 d of fly ash application in 1999, all rates of fly ash significantly increased soil pH above 6.0. Manganese levels in cotton petioles were reduced significantly by 6.7 and 10.1 Mg ha(-1) of fly ash. Soil boron (B) and sodium (Na) concentrations were significantly increased with fly ash. In 1999, B in cotton leaves ranged from 72 to 84 mg kg(-1) in plots with fly ash applications. However, no visual symptoms of B toxicity in plants were observed. In 1999, cotton lint yield decreased on average 12 kg ha(-1) for each Mg of fly ash applied. In 2000, cotton yields were significantly greater for the residual 3.4 and 6.7 Mg fly ash ha(-1) plots than the untreated check. Due to the adverse yield effects measured in the first year following application, fly ash would not be a suitable soil amendment for cotton on this soil at this time.  相似文献   
106.
This paper describes a study examining the potential of mineral magnetic, geochemical and organic properties to determine if a 2003 wildfire in a catchment in British Columbia, Canada, caused a change in the sources of the suspended sediment transported in the channel relative to a nearby unburnt (reference) catchment. The results show that some of the properties offer the potential to determine sediment sources in the unburnt catchment. However, the 2003 wildfire modified the concentrations of some properties and this can either compromise or enhance their ability as tracers in the burnt catchment. At present, the source tracing results are inconclusive. This has implications for the use of certain properties as fingerprints and raises important issues about approaches to sediment source identification.  相似文献   
107.
In order to elucidate the global distribution of dioxins and related compounds, such as PCDDs, PCDFs and coplanar PCBs, levels of these compounds were determined in the muscle of skipjack tuna (Katsuwonus pelamis) collected from the offshore waters and open seas near Japan, Taiwan, Philippines, Indonesia, Seychelles and Brazil, and the Japan Sea, the East China Sea, the South China Sea, the Indian Ocean and the North Pacific Ocean. PCDDs, PCDFs and coplanar PCBs were detected in almost all the specimens collected from all the locations surveyed, indicating widespread contamination by these compounds in the marine environment. Higher concentrations of dioxins and coplanar PCBs were detected in the samples from temperate Asian regions, plausibly due to larger usage and anthropogenic generation in highly industrialized countries around the East China Sea and the South China Sea, such as Japan, Korea, Taiwan, Hong Kong and coastal China.  相似文献   
108.
The Contribution of Headwater Streams to Biodiversity in River Networks1   总被引:1,自引:0,他引:1  
Abstract: The diversity of life in headwater streams (intermittent, first and second order) contributes to the biodiversity of a river system and its riparian network. Small streams differ widely in physical, chemical, and biotic attributes, thus providing habitats for a range of unique species. Headwater species include permanent residents as well as migrants that travel to headwaters at particular seasons or life stages. Movement by migrants links headwaters with downstream and terrestrial ecosystems, as do exports such as emerging and drifting insects. We review the diversity of taxa dependent on headwaters. Exemplifying this diversity are three unmapped headwaters that support over 290 taxa. Even intermittent streams may support rich and distinctive biological communities, in part because of the predictability of dry periods. The influence of headwaters on downstream systems emerges from their attributes that meet unique habitat requirements of residents and migrants by: offering a refuge from temperature and flow extremes, competitors, predators, and introduced species; serving as a source of colonists; providing spawning sites and rearing areas; being a rich source of food; and creating migration corridors throughout the landscape. Degradation and loss of headwaters and their connectivity to ecosystems downstream threaten the biological integrity of entire river networks.  相似文献   
109.
Organizational identification is defined as a perceived oneness with an organization and the experience of the organization's successes and failures as one's own. While identification is considered important to the organization, it has not been clearly operationalized. The current study tests a proposed model of organizational identification. Self-report data from 297 alumni of an all-male religious college indicate that identification with the alma mater was associated with: (1) the hypothesized organizational antecedents of organizational distinctiveness, organizational prestige, and (absence of) intraorganizational competition, but not with interorganizational competition, (2) the hypothesized individual antecedents of satisfaction with the organization, tenure as students, and sentimentality, but not with recency of attendance, number of schools attended, or the existence of a mentor, and (3) the hypothesized outcomes of making financial contributions, willingness to advise one's offspring and others to attend the college, and participating in various school functions. The findings provide direction for academic administrators seeking to increase alumni support, as well as for corporate managers concerned about the loyalty of workers in an era of mergers and takeovers.  相似文献   
110.
ABSTRACT: A method is presented for predicting base flow using easily measured, or estimated, hydrogeologic parameters. A mathematical model based upon the theory of subsurface flow to parallel drains is applied to a small watershed in Oklahoma. An example of model application is presented for a five-year period of record from this small watershed. Three years of data are used to calibrate the model, and two years of data are used for model validation. Hydrographs of observed and predicted base flow are presented for the five-year period of record. We concluded from this limited application of the model, on a small watershed, that the modeling techniques discussed herein were valid and should be tested for longer time periods on a larger watershed to determine their general applicability.  相似文献   
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