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951.
Wazir Singh Lakra Uttam Kumar Sarkar Rupali Sani Kumar Ajay Pandey Vineet Kumar Dubey Om Prakash Gusain 《The Environmentalist》2010,30(4):306-319
In the present communication habitat ecology, species diversity; distribution and different indices of fish biodiversity management
were studied in a Central India river (River Betwa, a tributary of River Ganga basin approved under India’s first river linking
plan). Correlation between fish species richness with the hydrological attributes showed good relationship and water depth,
dissolved oxygen and pH were found the most important variables in shaping fish assemblage. Altogether, sixty-three fish species
belonging to 20 families and 45 genera were collected from five sampling stations spread along the upstream, mid stream and
lower streams. Cyprinids were the most dominated group represented by 26 species belonging to 15 genera, followed by Bagridae
(6 species from 3 genera), and Schilbeidae (4 species from 4 genera). The distribution of fish showed interesting pattern
and about 10% species were common to all the sites showing long migration range. Shannon-Weiner diversity index showed considerable
variation and ranged from 1.89 to 3.51. Out of 63 species status of 10 species were not known due to data deficit, 29 categorized
as lower risk, 14 as vulnerable, 8 as endangered, while the remaining two species were introduced. Our study shows that the
River supports considerable diversity of the fishes and is important for conservation and about 34% fish fauna is threatened
being either vulnerable or endangered. We assessed that the river supports considerable percentage of food fish (89.47), ornamental
fish (49.12%) and sport fish (5.26%). Among the eight major types of fish habitats identified along the entire stretch of
river, open river, shallow water and deep pools were habitats contributing maximum diversity. Fish species richness (FSR)
were significantly different (P < 0.05) in all the habitats except channel confluence and scour pool. Trophic niche model may be useful for assessing altered
as well as less altered fish habitat of the tropical rivers. Since this river will be interlinked in near future, this study
would be useful for conservation planning and management and also for future assessment after interlinking. Issues related
to various threats to aquatic environment and conservation management strategies have been discussed. 相似文献
952.
953.
Jaya Kumar S Naik KA Ramanamurthy MV Ilangovan D Gowthaman R Jena BK 《Journal of environmental management》2008,89(1):35-44
The 26th December 2004 Indian Ocean tsunami devastated coastal regions of the Indian subcontinent. Andaman and Nicobar Islands, coastal stretches of Tamil Nadu, Andhra Pradesh and Kerala were the most affected regions of India. Changes in the beach profiles, long shore currents, breaking wave characteristics in the surf zone at selected locations along the Tamil Nadu coast were studied during January, April, October 2005 and January 2006. Long shore sediment transport rates were estimated from the observed parameters. Studies were carried out earlier (1995-1996 and 1998) to understand the coastal environment over a one-year cycle in the study region. The post-tsunami observations were compared with the earlier studies to establish the variations in the littoral environment and to ascertain the normalcy of the littoral environment in the post-tsunami scenario. From the changes in the beach profiles, the shoreline was observed to recede by about 20m and built-up of backshore by about 0.5m at most locations. Observations from the field investigations and comparisons with earlier studies along this stretch of the coastline indicate that the coastline is yet to return completely to normalcy. 相似文献
954.
This paper provides baseline information about the total annual dust fall, and its constituents and seasonal variation, from a sub-tropical opencast coalmine area in Bina, India. Dust samples were collected monthly for 2 years (June 2002-May 2004) from five sampling sites in the region and analyzed in the laboratory for water-soluble and -insoluble matter. Water-insoluble components constituted the major fraction of the total annual dust fall. Two-way ANOVA indicated significant variations in dust fall at different sites, over the months and in their interactions. The dust deposition rate was highest during summer (March-June), followed by winter (November-February) and lowest in the rainy season (July-October). Maximum dust fall was observed near the coal handling plant (at site 2) followed by the receiving pit of the coal handling plant (site 3), near the main sub-station (site 4), Jawahar colony (site 1) and Gharasari village (site 5). An inverse and significant relation was observed between dust fall and precipitation. Our studies have shown that the main residential areas are experiencing higher levels of dust fall which makes them unsuitable for living. We suggest that residential areas should be moved farther away from the mining area in the opposite direction of prevalent winds. 相似文献
955.
Concentration levels of polycyclic aromatic hydrocarbons (PAHs) have been determined in air and water in order to estimate the magnitude and direction of gas flux across the air-water interface at the creek adjoining the Mumbai harbour, India. The range of total PAHs was found to be 4.1-30.4 ng/m3 in air and 84.3-377.5 ng/l in seawater, respectively. The lower molecular weight PAHs revealed positive values of the fluxes indicating the tendency for transfer of these contaminants from water to air. In contrast, fluxes of less volatile compounds like benzo(k)fluoranthene and benzo(a)pyrene were always from the atmosphere into the surface water of the creek at all locations and sampling periods. While the fugacity ratio ranged from 0.12 to 6.97, it was found greater than 1 for the lower molecular weight PAHs and less than 1 for higher molecular weight PAHs. The present study suggests the active transfer of lower molecular weight dissolved PAHs into the atmosphere due to volatilization and deposition of higher molecular weight gas-phase PAHs into the surface water. 相似文献
956.
Sulfamethazine uptake by plants from manure-amended soil 总被引:12,自引:0,他引:12
Animal manure is applied to agricultural land as a means to provide crop nutrients. However, animal manure often contains antibiotics as a result of extensive therapeutic and subtherapeutic use in livestock production. The objective of this study was to evaluate plant uptake of a sulfonamide-class antibiotic, sulfamethazine, in corn (Zea mays L.), lettuce (Lactuca sativa L.), and potato (Solanum tuberosum L.) grown in a manure-amended soil. The treatments were 0, 50, and 100 microg sulfamethazine mL(-1) manure applied at a rate of 56 000 L ha(-1). Results from the 45-d greenhouse experiment showed that sulfamethazine was taken up by all three crops, with concentrations in plant tissue ranging from 0.1 to 1.2 mg kg(-1) dry weight. Sulfamethazine concentrations in plant tissue increased with corresponding increase of sulfamethazine in manure. Highest plant tissue concentrations were found in corn and lettuce, followed by potato. Total accumulation of sulfamethazine in plant tissue after 45 d of growth was less than 0.1% of the amount applied to soil in manure. These results raise potential human health concerns of consuming low levels of antibiotics from produce grown on manure-amended soils. 相似文献
957.
Critical review of EPS production, synthesis and composition for sludge flocculation 总被引:1,自引:0,他引:1
Klai Nouh Ram Saurabh Kumar Sellamuthu Balasubramanian Rajeshwar Dayal Tyagi 《环境科学学报(英文版)》2018,30(4):225-245
Extracellular polymeric substances(EPS) produced by microorganisms represent biological macromolecules with unfathomable potentials and they are required to be explored further for their potential application as a bioflocculant in various wastewater sludge treatment. Although several studies already exist on biosynthetic pathways of different classical biopolymers like alginate and xanthan, no dedicated studies are available for EPS in sludge. This review highlights the EPS composition, functionality, and biodegradability for its potential use as a carbon source for production of other metabolites. Furthermore, the effect of various extraction methods(physical and chemical) on compositional, structural, physical and functional properties of microbial EPS has been addressed. The vital knowledge of the effect of extraction method on various important attributes of EPS can help to choose the suitable extraction method depending upon the intended use of EPS. The possible use of different molecular biological techniques for enhanced production of desired EPS was summarized. 相似文献
958.
Revised algorithm for estimating light extinction from IMPROVE particle speciation data 总被引:14,自引:0,他引:14
Pitchford M Maim W Schichtel B Kumar N Lowenthal D Hand J 《Journal of the Air & Waste Management Association (1995)》2007,57(11):1326-1336
The Interagency Monitoring of Protected Visual Environments (IMPROVE) particle monitoring network consists of approximately 160 sites at which fine particulate matter (PM2.5) mass and major species concentrations and course particulate matter (PM10) mass concentrations are determined by analysis of 24-hr duration sampling conducted on a 1-day-in-3 schedule A simple algorithm to estimate light extinction from the measured species concentrations was incorporated in the 1999 Regional Haze Rule as the basis for the haze metric used to track haze trends. A revised algorithm was developed that is more consistent with the recent atmospheric aerosol literature and reduces bias for high and low light extinction extremes. The revised algorithm differs from the original algorithm in having a term for estimating sea salt light scattering from Cl(-) ion data, using 1.8 instead of 1.4 for the mean ratio of organic mass to measured organic carbon, using site-specific Rayleigh scattering based on site elevation and mean temperature, employing a split component extinction efficiency associated with large and small size mode sulfate, nitrate and organic mass species, and adding a term for nitrogen dioxide (NO2) absorption for sites with NO2 concentration information. Light scattering estimates using the original and the revised algorithms are compared with nephelometer measurements at 21 IMPROVE monitoring sites. The revised algorithm reduces the underprediction of high haze periods and the overprediction of low haze periods compared with the performance of the original algorithm. This is most apparent at the hazier monitoring sites in the eastern United States. For each site, the PM10 composition for days selected as the best 20% and the worst 20% haze condition days are nearly identical regardless of whether the basis of selection was light scattering from the original or revised algorithms, or from nephelometer-measured light scattering. 相似文献
959.
Sanjena Narayanasamydamodaran Jian e Zuo Haiteng Ren Nawnit Kumar 《Frontiers of Environmental Science & Engineering》2021,15(4):66
960.
An eco-sustainable green approach for heavy metals management: two case studies of developing industrial region 总被引:2,自引:0,他引:2
Rai PK 《Environmental monitoring and assessment》2012,184(1):421-448
Multifaceted issues or paradigm of sustainable development should be appropriately addressed in the discipline of environmental
management. Pollution of the biosphere with toxic metals has accelerated dramatically since the beginning of the Industrial
Revolution. In present review, comparative assessment of traditional chemical technologies and phytoremediation has been reviewed
particularly in the context of cost-effectiveness. The potential of phytoremediation and green chemicals in heavy metals management
has been described critically. Further, the review explores our work on phytoremediation as green technology during the last
6 years and hand in hand addresses the various ecological issues, benefits and constraints pertaining to heavy metal pollution
of aquatic ecosystems and its phytoremediation as first case study. Second case study demonstrates the possible health implications
associated with use of metal contaminated wastewater for irrigation in peri-urban areas of developing world. Our researches
revealed wetland plants/macrophytes as ideal bio-system for heavy metals removal in terms of both ecology and economy, when
compared with chemical treatments. However, there are several constraints or limitations in the use of aquatic plants for
phytoremediation in microcosm as well as mesocosm conditions. On the basis of our past researches, an eco-sustainable model
has been proposed in order to resolve the certain constraints imposed in two case studies. In relation to future prospect,
phytoremediation technology for enhanced heavy metal accumulation is still in embryonic stage and needs more attention in
gene manipulation area. Moreover, harvesting and recycling tools needs more extensive research. A multidisciplinary research
effort that integrates the work of natural sciences, environmental engineers and policy makers is essential for greater success
of green technologies as a potent tool of heavy metals management. 相似文献