全文获取类型
收费全文 | 452篇 |
免费 | 2篇 |
国内免费 | 6篇 |
专业分类
安全科学 | 16篇 |
废物处理 | 29篇 |
环保管理 | 62篇 |
综合类 | 41篇 |
基础理论 | 70篇 |
环境理论 | 1篇 |
污染及防治 | 155篇 |
评价与监测 | 69篇 |
社会与环境 | 16篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 8篇 |
2022年 | 34篇 |
2021年 | 17篇 |
2020年 | 4篇 |
2019年 | 8篇 |
2018年 | 10篇 |
2017年 | 12篇 |
2016年 | 11篇 |
2015年 | 9篇 |
2014年 | 25篇 |
2013年 | 58篇 |
2012年 | 26篇 |
2011年 | 19篇 |
2010年 | 18篇 |
2009年 | 15篇 |
2008年 | 20篇 |
2007年 | 22篇 |
2006年 | 19篇 |
2005年 | 23篇 |
2004年 | 14篇 |
2003年 | 8篇 |
2002年 | 9篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1994年 | 3篇 |
1992年 | 2篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1984年 | 2篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1968年 | 1篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1964年 | 2篇 |
1963年 | 1篇 |
1962年 | 2篇 |
1959年 | 2篇 |
1958年 | 1篇 |
1956年 | 2篇 |
1955年 | 2篇 |
排序方式: 共有460条查询结果,搜索用时 31 毫秒
131.
Duttagupta S Gupta S Gupta A 《Journal of environmental biology / Academy of Environmental Biology, India》2004,25(3):369-373
Red blooms of Euglena sp. in the floodplain wetland ecosystems of Barak Valley, Assam, India, were found to be induced by high concentrations of NH3-N, NO3, Fe, Mg and to some extent, PO4, Cu and Zn in their water. The trace elements were rapidly accumulated by the bloom organisms to high levels, whereby their concentrations in the water declined, leading to a collapse of the bloom, which tended to reappear as decomposition again led to the release of the nutrients. The bloom also harboured fairly high density of certain other algae and zooplankton, thereby acting as a sub-system within the wetland ecosystem. The bloom is non-toxic and is exploited as a fish food by the fish-farmers who artificially induce a bloom for augmenting the growth of surface-feeding species of fishes. 相似文献
132.
A revegetation trial was conducted to evaluate the feasibility of growing a legume species, Prosopis juliflora L., on fly ash ameliorated with combination of various organic amendments, blue-green algal biofertilizer and Rhizobium inoculation. Significant enhancements in plant biomass, photosynthetic pigments, protein content and in vivo nitrate reductase activity were found in the plants grown on ameliorated fly ash in comparison to the plants growing in unamended fly ash or garden soil. Higher growth was obtained in fly ash amended with blue-green algae (BGA) than farmyard manure or press mud (PM), a waste from sugar-processing industry, due to the greater contribution of plant nutrients, supply of fixed nitrogen and increased availability of phosphorus. Nodulation was suppressed in different amendments of fly ash with soil in a concentration-duration-dependent manner, but not with other amendments. Plants accumulated higher amounts of Fe, Mn, Cu, Zn and Cr in various fly ash amendments than in garden soil. Further, inoculation of the plant with a fly ash tolerant Rhizobium strain conferred tolerance for the plant to grow under fly ash stress conditions with more translocation of metals to the above ground parts. The results showed the potential of P. juliflora to grow in plantations on fly ash landfills and to reduce the metal contents of fly ash by bioaccumulation in its tissues. 相似文献
133.
Joshi N Gupta D 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(2):211-214
2, 4-dichlorophenoxyacetic acid (2,4-D) is a post emergence herbicide. The tests were conducted to study the toxicity of 2,4-D using EC50 value in four dilutions. 2,4-D was applied at concentration of 25, 50, 75, 100, 200 and 300 mg l(-1) in the potato Dextrose agar medium. The effect of this herbicide was evaluated as the colony forming unit (CFU). EC50 value for 10(-3) dilution of soil was 138 +/- 5.944 mg l(-1). Soil physico-chemical parameters and mycofloral properties were also evaluated. Qualitatively 10 genera of fungi were observed in untreated soil, whereas 4 genera were found in 2,4-D administered dose. 相似文献
134.
Singh N Gupta M Sirohi P Varsha 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(1):101-106
Alcoholic extract of whole fruit of Momordica charantia was prepared. Adult healthy albino rats were divided into four groups and received a dose of 6 mg/l00 gm. body weight of alloxan monohydrate. Animals of group I served as diabetic control group. The animals of II, III, and IV groups received 25 mg, 50 mg and 75 mg doses of the extract respectively for different durations. 75 mg dose showed increase in body weight. All doses of alcoholic extract of M. charantia were able to decrease the blood sugar level significantly. Extract feeding showed definite improvement in the islets of Langerhans. No toxic effect was observed in the liver The significant features of the study have been blood glucose once lowered by the treatment with M. charantia fruit extract remained static even after discontinuation of drug for 15 days. Blood sugar never fell below normal values even with a high dose, in pancreatic islets, beta cells showed definite improvement. 相似文献
135.
Kumar S Gupta A Yadav JP 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(2):227-232
The present investigation deals with fluoride removal from aqueous solution by thermally activated neem (Azadirachta indica) leaves carbon (ANC) and thermally activated kikar (Acacia arabica) leaves carbon (AKC) adsorbents. In this study neem leaves carbon and kikar leaves carbon prepared by heating the leaves at 400 degrees C in electric furnace was found to be useful for the removal of fluoride. The adsorbents of 0.3 mm and 1.0 mm sizes of neem and kikar leaves carbon was prepared by standard sieve. Batch experiments done to see the fluoride removal properties from synthetic solution of 5 ppm to study the influence of pH, adsorbent dose and contact time on adsorption efficiency The optimum pH was found to be 6 for both adsorbents. The optimum dose was found to be 0.5g/100 ml forANC (activated neem leaves carbon) and 0.7g/100 ml forAKC (activated kikar leaves carbon). The optimum time was found to be one hour for both the adsorbent. It was also found that adsorbent size of 0.3 mm was more efficient than the 1.0 mm size. The adsorption process obeyed Freundlich adsorption isotherm. The straight line of log (qe-q) vs time at ambient temperature indicated the validity of langergren equation consequently first order nature of the process involved in the present study. Results indicate that besides intraparticle diffusion there maybe other processes controlling the rate which may be operating simultaneously. All optimized conditions were applied for removal of fluoride from four natural water samples. 相似文献
136.
Pandey S Gupta K Mukherjee AK 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(3):655-662
The Madagascar Periwinkle, Catharanthus roseus (L.) G. Don (a valued medicinal plant) was exposed to different concentrations ofheavymetals like, CdCl, and PbCl, with a view to observe their bioaccumulation efficiency. Germination was inhibited by both the heavy metals in the seeds previously imbibed in GA, and KNO, for 24 hr. EC50 (the effective concentration which inhibits root length by 50%) was recorded as 180 microM for CdCl2, and 50 microM for PbCl2. Both alpha-amylase and protease activity were reduced substantially on treatment of seeds with increasing concentrations of CdCl2, and PbCl2. Malondialdehyde (MDA) a product of lipoxigenase (LOX) activity also increased due to the treatment of both CdCl, and PbCl2. When two-months-old plants grown in normal soil were transferred to soils containing increasing amounts of these two heavy metals, senescence of lower leaves and extensive chlorosis were noticed after four days of transfer However, plants gradually acclimatized and after 20 days the chlorophyll content was almost comparable to normal. Plants receiving CdCl2 treatment (250 microg g(-1) and less) became acclimatized after two weeks and started normal growth. But PbCl2 of 432 microg g(-1) and less could not affect the plant growth throughout, after a preliminary shock was erased. In case of CdCl2 treatment, a stunted growth with reduced leaf area, reduced biomass and sterility were recorded after six months, while plants show normal growth and flowering in case of PbCl2 treatment. Total alkaloid was also found to be decreased in the roots of CdCl2 treated plants. No change was observed in case of PbCl2. GA3 treatments to the CdCl2 treated plants show internode elongation and increase in leaf area with relatively elongated leaves and thinning of stem diameter AAS analyses of leaves of treated plants exhibited 5-10% accumulation of cadmium, but there was no accumulation of lead at all. 相似文献
137.
Gupta D Mittal RK Kant A Singh M 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(2):265-269
Correlation coefficient analysis conducted on 22 triticale x bread wheat derivatives along with six checks to select true- breeding derivative(s) for future hybridization programme with tolerance to drought and cold stress conditions as well as better quality traits revealed significant correlation of grain yield with spikelets per spike, biological yield, harvest index, leaf area index. Interestingly, the grain yield and drought susceptibility index showed no association. However, with cold tolerance it showed significant positive correlation indicating the desirability of certain plant traits under cold stress. The grain yield exhibited no association with quality traits which might assist in the predictability of high yielding varieties with high protein, total sugars, reducing sugars and non-reducing sugars. Path coefficient analysis revealed that biological yield had the highest positive direct effect on grain yield followed by harvest index, specific leaf weight, stomatal number, 1000 grain weight, stomatal size, spikelets per spike and days to heading. Therefore, indirect selection for these plant traits in order should be exercised in selecting drought tolerant genotypes. Two genotypes (RL-124-2P2 and RL 111P2) were found to be drought and cold tolerant with high grain yield, spikes per plant, spikelets per spike and leaf area index. 相似文献
138.
There has been considerable research on North–South issues on climate change; however, little work has been done on how the recent discovery of oil in some developing countries could affect North–South relations, the prospects for development for the South, climate change and local socio-environmental issues. Using the theory of inclusive development, the concept of the Right to Development, and their relation to stranded assets, this paper addresses the question: what does inclusive development imply at the national and global level in dealing with oil extraction in the context of climate change? Based on a literature review and a layered case study of Kenya, this paper concludes that (a) Kenyans argue that Kenya has a right to extract and use oil resources and that rich countries should reduce their extraction and use; (b) such a claim could be integrated in an appropriate emissions trading scheme; and that (c) Kenya should also account for the national and local socioecological aspects to reduce potential local conflict, yet the conditions favoring inclusive development are not yet established. However, such an argument may also lead to perverse results. If addressing climate change requires phasing out fossil fuels, this argument may lead to stranded assets in both developed and developing countries, and may ironically leave developing countries poorer off as stranded assets are possibly more expensive than having stranded resources. 相似文献
139.
Gupta Khushboo Kumar Raushan Baruah Kushal Kumar Hazarika Samarendra Karmakar Susmita Bordoloi Nirmali 《Environmental science and pollution research international》2021,28(24):30551-30572
Environmental Science and Pollution Research - Agricultural soil acts as a source and sink of important greenhouse gases (GHGs) like methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2).... 相似文献
140.
A Comprehensive Land-Use/Hydrological Modeling System for Scenario Simulations in the Elbow River Watershed, Alberta, Canada 总被引:1,自引:0,他引:1
Gayan Nishad Wijesekara Babak Farjad Anil Gupta Ying Qiao Patrick Delaney Danielle J. Marceau 《Environmental management》2014,53(2):357-381
The Elbow River watershed in Alberta covers an area of 1,238 km2 and represents an important source of water for irrigation and municipal use. In addition to being located within the driest area of southern Canada, it is also subjected to considerable pressure for land development due to the rapid population growth in the City of Calgary. In this study, a comprehensive modeling system was developed to investigate the impact of past and future land-use changes on hydrological processes considering the complex surface–groundwater interactions existing in the watershed. Specifically, a spatially explicit land-use change model was coupled with MIKE SHE/MIKE 11, a distributed physically based catchment and channel flow model. Following a rigorous sensitivity analysis along with the calibration and validation of these models, four land-use change scenarios were simulated from 2010 to 2031: business as usual (BAU), new development concentrated within the Rocky View County (RV-LUC) and in Bragg Creek (BC-LUC), respectively, and development based on projected population growth (P-LUC). The simulation results reveal that the rapid urbanization and deforestation create an increase in overland flow, and a decrease in evapotranspiration (ET), baseflow, and infiltration mainly in the east sub-catchment of the watershed. The land-use scenarios affect the hydrology of the watershed differently. This study is the most comprehensive investigation of its nature done so far in the Elbow River watershed. The results obtained are in accordance with similar studies conducted in Canadian contexts. The proposed modeling system represents a unique and flexible framework for investigating a variety of water related sustainability issues. 相似文献