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991.
G. M. Rabiul Islam Faysal Elahi Khan Md. Mozammel Hoque Yeasmin Nahar Jolly 《Environmental monitoring and assessment》2014,186(11):7233-7244
The concentrations of Cr, Cd, Pb, Hg, and As in water, poultry meat, fish, vegetables, and rice plants obtained from the area adjacent to the Hazaribag tannery campus, Dhaka, Bangladesh, were estimated and compared with permissible levels established by the WHO and FAO and levels reported previously by other authors. The metal contents were in the following order according to the concentration in contaminated irrigation water: Cr?>?Pb?>?As?>?Hg?>?Cd. Mean concentrations of Cr, Pb, Hg, and As in irrigated water were above the permissible levels, whereas the results were below the permissible levels for Cd. The metal concentrations in poultry meat, fish, rice, and vegetables were in the following orders: Pb?>?Cr?>?Cd?>?Hg?>?As, Pb?>?Cr?>?Cd?>?As?>?Hg, Pb?>?As, and Cr?>?Pb?>?Cd?>?As?>?Hg, respectively. The mean concentrations of metals in poultry meat, fish, rice, and vegetables were much higher than the permissible levels. The trends of weekly intake of heavy metals (WIMs) from poultry meat, fish, rice, and vegetables were as follows: Pb?>?Cr?>?Cd?>?Hg?>?As, Pb?>?Cr?>?Cd?>?As?>?Hg, Pb?>?As, and Cr?>?Pb?>?Cd?>?As?>?Hg, respectively. WIMs for all the metals were lower than the provisional maximum weekly intake recommended by WHO/FAO and USNAS. 相似文献
992.
Bruce E. Underwood Natalie A. Kruse Jennifer R. Bowman 《Environmental monitoring and assessment》2014,186(11):7539-7553
Acid mine drainage (AMD) is a common result of coal and metal mining worldwide caused by weathering of metal sulfides exposed during mining. AMD typically results in low-pH, high-metal, high-conductivity water that does not support aquatic life. Chemical water quality improvement does not necessarily lead to rapid biological recovery. Little Raccoon Creek, a major tributary to Raccoon Creek in the Western Allegheny Plateau of Ohio, drains 401 km2, has a legacy of AMD that stems from mining activities over more than a century. Since 1999, seven major passive treatments systems have been installed in the watershed to a total of over $6.5 million. This study analyzes the hourly water quality data collected at a United States Geological Survey gage station alongside trends in fish and macroinvertebrate communities. Both fish and macroinvertebrate communities have shown a statistically significant improvement in the lower reaches of Little Raccoon Creek since treatment began. Long-term chemical monitoring shows a significant increase in pH, but no significant change in conductivity. The conductivity data is well correlated with sulfate concentrations and discharge, while the pH is well correlated with net alkalinity data, but not with discharge. Significant investment in passive treatment systems and land reclamation has decreased the percent occurrence of pH measurements below the target of 6.5 and has led to recovery of both fish and macroinvertebrate communities in the downstream reaches of Little Raccoon Creek. Long-term monitoring has proven to be a valuable tool to assess success of a high-cost remediation program. 相似文献
993.
M. F. Zawrah M. A. Ebiad A. M. Rashad E. El-Sayed Moustafa Gamal Snousy M. A. Tantawy 《Environmental monitoring and assessment》2014,186(11):7579-7591
Soil and groundwater contamination is one of the important environmental problems at petroleum-related sites, which causes critical environmental and health defects. Severe petroleum hydrocarbon contamination from coastal refinery plant was detected in a shallow Quaternary sandy aquifer is bordered by Gulf in the Northwestern Gulf of Suez, Egypt. The overall objective of this investigation is to estimate the organic hydrocarbons in shallow sandy aquifers, released from continuous major point-source of pollution over a long period of time (91 years ago). This oil refinery contamination resulted mainly in the improper disposal of hydrocarbons and produced water releases caused by equipment failures, vandalism, and accidents that caused direct groundwater pollution or discharge into the gulf. In order to determine the fate of hydrocarbons, detailed field investigations were made to provide intensive deep profile information. Eight composite randomly sediment samples from a test plot were selected for demonstration. The tested plot was 50 m long?×?50 m wide?×?70 cm deep. Sediment samples were collected using an American auger around the point 29° 57′ 33″ N and 32° 30′ 40″ E in 2012 and covered an area of 2,500 m2 which represents nearly 1/15 of total plant area (the total area of the plant is approximately 3.250 km2). The detected total petroleum hydrocarbons (TPHs) were 2.44, 2.62, 4.54, 4.78, 2.83, 3.22, 2.56, and 3.13 wt%, respectively. TPH was calculated by differences in weight and subjected to gas chromatography (GC). Hydrocarbons were analyzed on Hewlett–Packard (HP-7890 plus) gas chromatograph equipped with a flame ionization detector (FID). The percentage of paraffine of the investigated TPH samples was 7.33, 7.24, 7.58, 8.25, 10.25, 9.89, 14.77, and 17.53 wt%, respectively. 相似文献
994.
David T. Rios Sudeep Chandra Alan C. Heyvaert 《Environmental monitoring and assessment》2014,186(11):7893-7907
Urban land use has been implicated as a major contributor of nonpoint source pollution in aquatic systems. Through increased nonpoint delivery of pollutants, including constituents found in stormwater, Lake Tahoe is undergoing a marked decline in its transparency, primarily due to increasing production of algae from enhanced nutrient loading and delivery of fine particles to the lake from the watershed. In response to these findings, a regional restoration effort is underway to improve basin watersheds and the water quality in Lake Tahoe. In this study, stormwater autosamplers were used to collect flow-weighted composite samples that characterized event mean concentrations for event and nonevent conditions within a small, urbanized watershed in the Tahoe basin. An event-specified constant-concentration water quality model was then applied to the event mean concentration and continuous streamflow data to estimate pollutant loads for nitrate, nitrite, ammonia, orthophosphate, and suspended sediment. These data were compared with previously reported load estimates from 10 primary monitored streams in larger watersheds of the Tahoe basin. Results from a linear regression analysis demonstrate strong and significant relationships between watershed impervious area and pollutant loadings from Lake Tahoe watersheds. These small, urbanized watersheds and intervening zones, which only comprise 10 % of the total Lake Tahoe drainage area, include a significant portion of the total Lake Tahoe impervious area. The findings of this study suggest that small, urbanized watersheds and intervening zones are disproportionately important contributors of nonpoint source pollution, including nutrients and suspended particles. 相似文献
995.
Can adaptive modulation of traits to urban environments facilitate Ricinus communis L. invasiveness?
Neha Goyal P. Pardha-Saradhi Gyan P. Sharma 《Environmental monitoring and assessment》2014,186(11):7941-7948
This paper addresses the phenotypic variation among Ricinus communis L. populations in four urban habitat types (road verges, garbage dumps, construction debris, and natural area) in Delhi, India, by evaluating important traits such as plant height, basal circumference, seeds per plant, seed size, seed weight, specific leaf area, and reproductive index. An important biochemical marker, proline, considered as a good plant performance indicator under stress was also quantified in leaves of R. communis to evaluate its response in different habitats. Interestingly, the species showed significant variation in plant height, specific leaf area, seed size, seed weight, and leaf proline content in different habitat types. Leaf proline content was positively related to plant height, specific leaf area, and seed size while negatively related to the total number of seeds/plant. Interestingly, reproductive index, calculated as a ratio of the total number of seeds to the plant height also showed a negative relation with leaf proline content. Results indicated that R. communis exhibits adaptive modulation of growth, reproductive traits, and leaf proline content in various urban habitats which contributes to invasiveness, range expansion, and establishment of the species. The study also gives evidence of how morphological and physiological traits could directly affect invasiveness of R. communis. 相似文献
996.
Maria Virgínia Alves Martins Fabrizio Frontalini Lazaro L. M. Laut Frederico S. Silva João Moreno Silvia Sousa Noureddine Zaaboub Monia El Bour Fernando Rocha 《Environmental monitoring and assessment》2014,186(12):8875-8897
Ria de Aveiro, which is located in the centre of Portugal (40° 38′ N, 8° 45′ W), is a well-mixed and complex coastal lagoon that is separated from the sea by a sandy barrier and connects with the Atlantic through an artificial inlet. Tidal currents are the main factor controlling the lagoon’s hydrodynamics and, to a great extent, the sedimentary dynamic. The inner lagoonal zones receive input from several rivers and experience the pressure caused by the accumulation of organic matter and pollutants (namely, trace metals) from diverse anthropic activities. This paper is the first piece of work aiming to recognize, characterize and explain the main benthic foraminiferal biotopes in Ria de Aveiro. To provide a broad overview of this kind of setting, our results are compared to those of previous published studies conducted in similar transitional environments. The research is based on an investigation of 225 sites spread throughout this ecosystem. Utilizing a statistical approach, this study analyses the details of dead benthic foraminiferal assemblages composed of 260 taxa, the texture and composition (mineralogical and geochemical) of the sediment and physicochemical data. On the basis of the results of R-mode and Q-mode cluster analyses, several different biotopes can be defined as marsh biotope/near-marsh biotope; marginal urban/marginal urban mixing biotope; inner-outer lagoon biotope or enclosed lagoon; outer lagoon biotope, mixed sub-biotope; and outer lagoon, marine sub-biotope. These biotopes are related to foraminifera assemblages and substrate type and are influenced by local currents, water depth, chemical and physicochemical conditions, river or oceanic proximity, and anthropogenic impact, as evidenced by the mapping of the six factor loadings of the principal component analysis conducted herein. Based on a similar methodology of analysis as that applied in previous studies in the Lagoon of Venice, comparable biotypes were identified in Lagoon of Aveiro. 相似文献
997.
L. E. Miranda 《Environmental monitoring and assessment》2014,186(12):8899-8905
Electrofishing is widely used to monitor fish species composition and relative abundance in streams and lakes. According to standard protocols, multiple segments are selected in a body of water to monitor population relative abundance as the ratio of total catch to total sampling effort. The standard protocol provides an assessment of fish distribution at a macrohabitat scale among segments, but not within segments. An ancillary protocol was developed for assessing fish distribution at a finer scale within electrofishing segments. The ancillary protocol was used to estimate spacing, dispersion, and association of two species along shore segments in two local reservoirs. The added information provided by the ancillary protocol may be useful for assessing fish distribution relative to fish of the same species, to fish of different species, and to environmental or habitat characteristics. 相似文献
998.
The flow curve of anaerobically digested wastes from different origins was determined through rheological measurements. Regardless of their origin, samples can be divided into two families: simple non-Newtonian liquids well modelled by basic power law below 10%DC and viscoelastic liquids with a yield stress, well modelled by a Herschel–Bulkley model above. In all the cases, the rheological behaviour is driven by both the organic content and the volatile fraction (organic content/solid content), indicating that anaerobic digestion tends to smooth the rheological characteristics of organic wastes, whichever their origins. 相似文献
999.
Kusum Komal Karati G. Vineetha N. V. Madhu P. Anil M. Dayana B. K. Shihab A. I. Muhsin C. Riyas T. V. Raveendran 《Environmental monitoring and assessment》2017,189(12):653
El Niño, an interannual climate event characterized by elevated oceanic temperature, is a prime threat for coral reef ecosystems worldwide, owing to their thermal threshold sensitivity. Phytoplankton plays a crucial role in the sustenance of reef trophodynamics. The cell size of the phytoplankton forms the “master morphological trait” with implications for growth, resource acquisition, and adaptability to nutrients. In the context of a strong El Niño prediction for 2015–2016, the present study was undertaken to evaluate the variations in the size-structured phytoplankton of Kavaratti reef waters, a major coral atoll along the southeast coast of India. The present study witnessed a remarkable change in the physicochemical environment of the reef water and massive coral bleaching with the progression of El Niño 2015–2016 from its peak to waning phase. The fluctuations observed in sea surface temperature, pH, and nutrient concentration of the reef water with the El Niño progression resulted in a remarkable shift in phytoplankton size structure, abundance, and community composition of the reef waters. Though low nutrient concentration of the waning phase resulted in lower phytoplankton biomass and abundance, the diazotroph Trichodesmium erythraeum predominated the reef waters, owing to its capability of the atmospheric nitrogen fixation and dissolved organic phosphate utilization. 相似文献
1000.
Vulnerability assessments are a cornerstone of contemporary disaster research. This paper shows how research procedures and the presentation of results of vulnerability assessments are politically filtered. Using data from a study of tsunami risk assessment in Portugal, the paper demonstrates that approaches, measurement instruments, and research procedures for evaluating vulnerability are influenced by institutional preferences, lines of communication, or lack thereof, between stakeholder groups, and available technical expertise. The institutional setting and the pattern of stakeholder interactions form a filter, resulting in a particular conceptualisation of vulnerability, affecting its operationalisation via existing methods and technologies and its institutional embedding. The Portuguese case reveals a conceptualisation that is aligned with perceptions prevalent in national government bureaucracies and the exclusion of local stakeholders owing to selected methodologies and assessment procedures. The decisions taken by actors involved in these areas affect how vulnerability is assessed, and ultimately which vulnerability reduction policies will be recommended in the appraisal. 相似文献