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901.
This study aimed to assess how poor planning for irrigation led to heavy salt loads, how those salt loads adversely affected the environment, and how to identify management practices to deal with these potential problems in the Great Menderes River Basin, Aydin Plain Irrigation Scheme of Turkey for the period between 2000 and 2006. In order to determine the effects on the environment; electrical conductivity, salinity load, total amount of water table salinity, inflow and outflow salinity were measured and calculated for the research area. There was no problem on account of water table fluctuations. The mean of area prevented the plant growth by high water table was 8.5%. The percentage of the area occurring water table salinity problem was 39.2. The total amount of salt transported to the Great Menderes River and accumulated in the soil of the research area was 211,609 and 246,565 tones respectively. Salt, 458,174 tones in total, had adverse effects on the environment.  相似文献   
902.
The purpose of this study is to outline the theme of saving energy resources and its relationship with the preservation of the environment, as well as the importance of green marketing in achieving sustainability. The model of data collection was a survey conducted by self-administered questionnaire. After collection, the data were statistically analysed and interpreted. Most individuals claim to be concerned about environmental problems, with 68% of these belonging to the ‘Savers’ group. However, even though they may be concerned with environmental problems, the vast majority of individuals do not have any system of renewable energy in their homes, despite claiming that renewable energies are a viable option for protecting the environment. Women display behaviour that is more favourable to the saving of energy resources than do men. Educational levels are not significant for distinguishing the more pro-environmental individuals from the others.  相似文献   
903.
This study describes the first attempt to validate a Portuguese natural soil (PTRS1) to be used as reference soil for ecotoxicological purposes, aimed to both: (i) obtain ecotoxicological data for the derivation of Soil Screening Values (SSVs) with regional relevance, acting as a substrate to be spiked with ranges of concentrations of the chemicals under evaluation and (ii) act as control and as substrate for the dilution of contaminated soils in ecotoxicological assays performed to evaluate the ecotoxicity of contaminated soils, in tier 2 of risk assessment frameworks, applied to contaminated lands. The PTRS1 is a cambisol from a granitic area integrated in the Central Iberian Zone. After chemical characterization of the soil in terms of pseudo-total metals, PAHs, PCBs and pesticide contents, it was possible to perceive that some metals (Ba, Be, Co, Cr and V) surpass the Dutch Target Values (Dtvs) corrected for the percentage of organic matter and clay of the PTRS1. Nevertheless, these metals displayed total concentrations below the background total concentrations described for Portuguese soils in general. The same was observed for aldrin, endosulfan I, endosulfan II, heptachlor epoxide, and heptachlor; however the Dtvs corrected become negligible. The performance of invertebrate and plant species, commonly used in standard ecotoxicological assays, was not compromised by both soil properties and soil metal contents. The results obtained suggest that the PTRS1 can be used as a natural reference soil in ecotoxicological assays carried out under the scope of ecological risk assessment.  相似文献   
904.
Paraeuchaeta norvegica (8.5 mm total length) and yolk-sac stage Atlantic cod larvae (4 mm total length) (Gadus morhua) larvae were observed in aquaria (3 l of water) using silhouette video photography. This allowed direct observations (and quantitative measurement) of predator–prey interactions between these two species in 3-dimensions. Tail beats, used by cod larvae to propel themselves through the viscous fluid environment, also generate signals detectable by mechanoreceptive copepod predators. When the prey is close enough for detection and successful capture (approximately half a body-length), the copepod launches an extremely rapid high Reynolds number attack, grabbing the larva around its midsection. While capture itself takes place in milliseconds, minutes are required to subdue and completely ingest a cod larva. The behavioural observations are used to estimate the hydrodynamic signal strength of the cod larva’s tail beats and the copepod’s perceptive field for larval fish prey. Cod larvae are more sensitive to fluid velocity than P. norvegica and also appear capable of distinguishing between the signal generated by a swimming and an attacking copepod. However, the copepod can lunge at much faster velocities than a yolk-sac cod larva can escape, leading to the larva’s capture. These observations can serve as input to the predator–prey component of ecosystem models intended to assess the impact of P. norvegica on cod larvae.  相似文献   
905.
Grünewald F 《Disasters》2012,36(Z1):S105-S125
Mogadishu, the capital of Somalia, has been central to life, war, and peace in the country for almost two decades. Its urban characteristics, though, have been put to one side for the most part. In recent years, Mogadishu-related issues have been merged mostly into a global agenda for South and Central Somalia, resulting in the technical and coordination approaches employed in the city largely being reproductions of solutions utilised in refugee camps and rural areas. Unfortunately, urban problems require urban solutions. The aid system is just starting to discover how specific aid in cities at war should be, both from an organisational and a technical standpoint. The enhancement of aid practices in an urban setting implies, among other things, a more strategic approach to the specific spatial characteristics of the city, a more fine-tuned analysis of the technical requirements of the urban service delivery systems, and a better understanding of the role of urban institutions.  相似文献   
906.
Abstract: Snowmelt largely affects runoff in watersheds in Nordic countries. Neural networks (NN) are particularly attractive for streamflow forecasting whereas they rely at least on daily streamflow and precipitation observations. The selection of pertinent model inputs is a major concern in NNs implementation. This study investigates performance of auxiliary NN inputs that allow short‐term streamflow forecasting without resorting to a deterministic snowmelt routine. A case study is presented for the Rivière des Anglais watershed (700 km2) located in Southern Québec, Canada. Streamflow (Q), precipitations (rain R and snow S, or total P), temperature (T) and snow lying (A) observations, combined with climatic and snowmelt proxy data, including snowmelt flow (QSM) obtained from a deterministic model, were tested. NN implemented with antecedent Q and R produced the largest gains in performance. Introducing increments of A and T to the NNs further improved the performance. Long‐term averages, seasonal data, and QSM failed to improve the networks.  相似文献   
907.
We investigated conventional characterization of wastewaters of the "Kullar Domestic Wastewater Treatment Plant." In the study of conventional characterization; 23 composite samples, which were taken during 10 months, were used and analysed as COD, BOD5, TKN, NH3-N, SS, VSS, TP, RP, TS, Alkalinity, oil and grease, detergent, chloride parameters. For determine of the plant efficiency, 8 output grab samples were taken. The COD and BOD5 values of influent, respectively, ranging from 37 to 1,056 mg/L and 8 to 140 mg/L in total wastewater. The meanly BOD5/COD ratio was calculated as 0.34 in total wastewaters.  相似文献   
908.
In this study, the characteristics, benefits, and effects of the environment and ecology project, which has been implemented in Turkey for the first time to restore the natural life that has been spoilt and the ecological balance of Lake Bafa located in Great Meander Basin, are searched. Moreover, the water samples taken from the stations that were spotted in the lake have been analyzed for the physical and chemical changes taking place in water quality before and after the project. The water cycle occurring as a result of giving water that was raised in Great Meander River by the Rubber regulator, which is the most important element of the project, through the Serçin inlet and feeder channel; and draining the saline and low-quality water to the river bed of the Great Meander, will improve the water quality, the natural life, and the ecological balance of the lake in time. Thanks to the water given to the lake within the scope of project, the salinity of the lake water decreased from 25,500 to 22,500 mmhos cm???1. The electrical conductivity, Na?+?, Mg?+?2, Ca?+?2, Cl???, $\text{CO}_\text{3} ^{-\text{2}}In this study, the characteristics, benefits, and effects of the environment and ecology project, which has been implemented in Turkey for the first time to restore the natural life that has been spoilt and the ecological balance of Lake Bafa located in Great Meander Basin, are searched. Moreover, the water samples taken from the stations that were spotted in the lake have been analyzed for the physical and chemical changes taking place in water quality before and after the project. The water cycle occurring as a result of giving water that was raised in Great Meander River by the Rubber regulator, which is the most important element of the project, through the Ser?in inlet and feeder channel; and draining the saline and low-quality water to the river bed of the Great Meander, will improve the water quality, the natural life, and the ecological balance of the lake in time. Thanks to the water given to the lake within the scope of project, the salinity of the lake water decreased from 25,500 to 22,500 mmhos cm( - 1). The electrical conductivity, Na+, Mg+2, Ca+2, Cl(-), CO3(-2), HCO3(-), and the amount of the organic substances were found as over the appropriate values for fishery. Besides, the decreases in the amounts of NO3(-), HN3(-) and PO4(-3) affect the living beings in the lake negatively. In addition, the measures to take are specified, so that the natural life of the Lake and the ecological balance can renew themselves within a short time.  相似文献   
909.
This work was conducted to investigate the possibility of using stillage from ethanol distilleries as substrate for sulfate reducing bacteria (SRB) growth and to evaluate the removal efficiency of heavy metals present in wastewaters containing sulfates. The experiments were carried out in a continuous bench-scale Upflow Anaerobic Sludge Blanket reactor (13 l) operated with a hydraulic retention time of 18 h. The bioreactor was inoculated with 7 l of anaerobic sludge. Afterwards, an enrichment procedure to increase SRB numbers was started. After this, cadmium and zinc were added to the synthetic wastewater, and their removal as metal sulfide was evaluated. The synthetic wastewater used represented the drainage from a dam of a metallurgical industry to which a carbon source (stillage) was added. The results showed that high percentages of removal (>99%) of Cd and Zn were attained in the bioreactor, and that the removal as sulfide precipitates was not the only form of metal removal occurring in the bioreactor environment.  相似文献   
910.
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