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221.
Assessing Risk in Operational Decisions Using Great Lakes Probabilistic Water Level Forecasts 总被引:1,自引:0,他引:1
/ A method adapted from the National Weather Service's Extended Streamflow Prediction technique is applied retrospectively to three Great Lakes case studies to show how risk assessment using probabilistic monthly water level forecasts could have contributed to the decision-mak-ing process. The first case study examines the 1985 International Joint Commission (IJC) decision to store water in Lake Superior to reduce high levels on the downstream lakes. Probabilistic forecasts are generated for Lake Superior and Lakes Michigan-Huron and used with riparian inundation value functions to assess the relative impacts of the IJC's decision on riparian interests for both lakes. The second case study evaluates the risk of flooding at Milwaukee, Wisconsin, and the need to implement flood-control projects if Lake Michigan levels were to continue to rise above the October 1986 record. The third case study quantifies the risks of impaired municipal water works operation during the 1964-1965 period of extreme low water levels on Lakes Huron, St. Clair, Erie, and Ontario. Further refinements and other potential applications of the probabilistic forecast technique are discussed.KEY WORDS: Great Lakes; Water levels; Forecasting; Risk; Decision making 相似文献
222.
Marc Bekoff 《Journal of Agricultural and Environmental Ethics》1997,10(3):269-296
In this essay I argue that the evolutionary and comparative study of nonhuman animal (hereafter animal) cognition in a wide
range of taxa by cognitive ethologists can readily inform discussions about animal protection and animal rights. However,
while it is clear that there is a link between animal cognitive abilities and animal pain and suffering, I agree with Jeremy
Bentham who claimed long ago the real question does not deal with whether individuals can think or reason but rather with
whether or not individuals can suffer. One of my major goals will be to make the case that the time has come to expand. The
Great Ape Project (GAP) to The Great Ape/Animal Project (GA/AP) and to take seriously the moral status and rights of all animals
by presupposing that all individuals should be admitted into the Community of Equals. I also argue that individuals count
and that it is essential to avoid being speciesist cognitivists; it really doesn't matter whether ‘dogs ape’ or whether ‘apes
dog’ when taking into account the worlds of different individual animals. Narrow-minded primatocentrism and speciesism must
be resisted in our studies of animal cognition and animal protection and rights. Line-drawing into ‘lower’ and ‘higher’ species
is a misleading speciesist practice that should be vigorously resisted because not only is line-drawing bad biology but also
because it can have disastrous consequences for how animals are viewed and treated. Speciesist line-drawing also ignores within
species individual differences.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
223.
Winter Quarters Bay (WQB) is a small embayment located adjacent to McMurdo Station, the largest researchbase in Antarctica. The bay is approximately 250 m wide andlong, with a maximum depth of 33 m. Historically, trashfrom the McMurdo Station was piled on the steep shoreline ofWQB, doused with fuel and ignited. That practice hasceased, and the adjacent land area has been regraded tocover the residual waste. The bottom of WQB remainslittered with drums, equipment, tanks, tires, cables, andother objects, especially the southeastern side of the baywhere dumping took place. Sediments are contaminated withPCBs, metals, and hydrocarbon fuels. The objectives of this study were to map the distributionof organic contaminants in WQB, assess the toxicity of WQB sediments using a simple microbial test, anddetermine correlations between toxicity and contaminantlevels. The study suggests that adverse ecological effectshave occurred from one or more of the contaminants found inWQB but the source of the toxic impacts to bay sedimentsremains unknown. Whole sediment toxicity was onlycorrelated with oil-equivalent while solvent extracts ofsediments were correlated with PAHs and oil-equivalent. Theauthors recommend that an integrated research plan bedeveloped that focuses on determining what additionalinformation is needed to make informed decisions on possibleremediation of WQB. 相似文献
224.
Neilson MA Painter DS Warren G Hites RA Basu I Weseloh DV Whittle DM Christie G Barbiero R Tuchman M Johannsson OE Nalepa TF Edsall TA Fleischer G Bronte C Smith SB Baumann PC 《Environmental monitoring and assessment》2003,88(1-3):103-117
The Great Lakes Water Quality Agreement stipulates that the Governments of Canada and the United States are responsible for restoring and maintaining the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem. Due to varying mandates and areas of expertise, monitoring to assess progress towards this objective is conducted by a multitude of Canadian and U.S. federal and provincial/state agencies, in cooperation with academia and regional authorities. This paper highlights selected long-term monitoring programs and discusses a number of documented ecological changes that indicate the present state of the open and nearshore waters of the Great Lakes. 相似文献
225.
D.P. Ryckman D.V. Weseloh P. Hamr G.A. Fox B. Collins P.J. Ewins R.J. Norstrom 《Environmental monitoring and assessment》1998,53(1):169-195
The levels of organochlorine contaminants (OCs) in the eggs of double-crested cormorants (Phalacrocorax auritus) from the Canadian Great Lakes, Lake Nipigon and Lake-of-the-Woods were monitored between 1970 and 1995. PCBs and p,p-DDE were present at the highest concentrations. Significant declines in OC concentrations on the Great Lakes were observed over this period for Lake Ontario, Lake Superior, Georgian Bay and North Channel but not Lake Erie where levels remained relatively stable. In the early 1970s, the greatest OC levels were generally observed in cormorant eggs from nesting sites in Georgian Bay and North Channel of Lake Huron. Between 1984 and 1995 mirex and PCB levels were consistently highest in samples from Lakes Ontario and Erie, respectively. Similar levels of PCDDs and PCDFs were observed from all regions of the Canadian Great Lakes in 1989. In general, OC levels in cormorant eggs between 1984-95 were ranked as follows: Lake Erie>Lake Ontario Lake Superior>Lake Huron. In 1995, eggshell thickness in Canadian Great Lakes cormorants, ranged from 0.423 to 0.440 mm and was on average only 2.3% thinner than pre-DDT era values. Between 1988 and 1996, 31 cormorant chicks with bill defects were observed at 16 different colonies (21% of all colonies surveyed) in Lakes Ontario and Superior, Georgian Bay and North Channel, and the main body of Lake Huron. No bill deformities were observed at reference sites in northwestern Ontario (Lake Nipigon and Lake-of-the-Woods). For the period 1988-96, the prevalence of bill defects in cormorant chicks (0.0 to 2.8/10,000 chicks) did not differ significantly (P > 0.05) among most regions in the Canadian Great Lakes. Georgian Bay was the only region to show a significant decrease in the prevalence of bill defects between the periods 1979-87 and 1988-95. 相似文献
226.
A. B. Crockett 《Environmental monitoring and assessment》1997,47(1):39-57
McMurdo Station is the largest research station in Antarctica and has a population that ranges from 250 to 1200 people. Wastewater from the Station is macerated, was sometimes mixed with waste brine from the desalinization plant and is discharged to McMurdo Sound. Effluent water quality has been routinely monitored since 1989, and a special ambient water quality study was conducted by Idaho National Engineering Laboratory (INEL) personnel in 1992. Results of the effluent monitoring efforts show that low concentrations of a few organic contaminants have been detected, while concentrations of metals, particularly copper, are considerably higher. Ambient water quality and sea ice monitoring detected very few contaminants, all at very low levels. Only minor and variable dissolved oxygen depression was detected near the outfall. Diatom communities near the outfall differ in relative abundance, cell counts, and chlorophyll a content compared to control sites. For the purpose of evaluating the impact of McMurdo`s effluent on ambient water quality, improved effluent monitoring and sediment quality monitoring are recommended instead of frequent monitoring of ambient water quality. 相似文献
227.
通过有效运行的环境监测质量管理体系和实施监测全过程质量管理对虹口区环境监测站质量管理现状进行分析,提出了对策及建议,结果,通过建立数学分析模型对监测数据进行综合分析,实验室工作逐步做到熟练地应用测量不确定度,使环境监测站质量管理水平进一步提高,更好的为环境管理服务. 相似文献
228.
Pimentel D 《Environmental management》2005,35(5):692-702
A total of 154 aquatic alien species have invaded the New York State Canal and Hudson River systems and a total of 162 aquatic species have invaded the Great Lakes Basin. Some of these invasive species are causing significant damage and control costs in both aquatic ecosystems. In the New York State Canal and Hudson River systems, the nonindigenous species are causing an estimated 500 million dollars in economic losses each year. The economic and environmental situation in the Great Lakes Basin is far more serious from nonindigenous species, with losses estimated to be about 5.7 billion dollars per year. Commercial and sport fishing suffer the most from the biological invasions, with about 400 million dollars in losses reported for the New York State Canal and Hudson River systems and 4.5 billion dollars in losses reported for the Great Lakes Basin. 相似文献
229.
Theodore K. Miller Lawrence J. Onesti 《Journal of the American Water Resources Association》1988,24(6):1207-1217
ABSTRACT: Stream channel development is a complicated process involving many factors. A major goal of research in fluvial geomorphology is to develop an understanding of the relations between channel form, water discharge, and sediment discharge characteristics. The concept of thresholds has been introduced as an element in fluvial processes, with the implication that the factors involved in a process might change in some way as threshold boundaries are passed. This study is focused on the extent to which a particular regional boundary represents a threshold in the process of stream channel development. Twenty-four alluvial stream channels from the Great Plains region and 24 from the Central Lowlands region are compared with regard to the distributional form, central tendency and dispersion characteristics, and correlation structure of ten variables, including indicators of discharge, channel sediment, and channel morphology. The results suggest that these aspects of the data are very similar between the regions, except for certain differences in central tendency characteristics, which are assumed to reflect underlying differences between the regions in geology and climate. In general, the results support the idea that this regional boundary is not an effective threshold with respect to the stream channel development process, and that, therefore, stream channels develop in these environmentally distinct regions by way of a similar process. 相似文献
230.
ABSTRACT. Beginning of month water temperature profiles are estimated for each lake. These water temperature profiles along with surface water temperatures are used to determine the effects of thermal expansion and contraction of water on the net basin supply values obtained from water balance studies using end of month lake levels. It is demonstrated that net basin supply values (equivalent to precipitation on the lake minus the evaporation from the lake plus the runoff into the lake) obtained from water balance studies without accounting for the thermal expansion and contraction of water may be in error by as much as 100 percent during some months for each lake. 相似文献