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204.
Manuel Pedro Rodríguez Bolívar Raquel Garde Sánchez Antonio M. López Hernández 《Journal of Environmental Planning and Management》2015,58(5):777-801
Corporate social responsibility (CSR) is increasingly required not only of private sector companies, but also of state-owned enterprises (SOEs), whose main function is to provide services to society and not principally to obtain financial reward. The important role played by managers in implementing CSR has been demonstrated by prior research. The objective of this paper is to examine how managers of SOEs perceive the concept of CSR, the reasons for their involvement and how it is integrated into everyday business practices. In addition, we examine whether managers' attitudes towards CSR policies are influenced by their personal profiles and by the sector in which the SOEs work. We find that, although these managers are aware of the importance of the CSR principles underlying their activities and understand the meaning, scope and dimensions of CSR, there remains an evident need to enhance the application of CSR policies among the strategies of SOEs. The manager profile and the sector in which the SOEs work both have a strong influence on their behaviour regarding CSR issues. 相似文献
205.
Miguel C. Leal Stella A. Berger Christine Ferrier-Pagès Ricardo Calado Jay Brandes Marc E. Frischer Jens C. Nejstgaard 《Marine Biology》2014,161(9):2191-2197
Gorgonians are widespread sub-littoral benthic suspension feeders in the world oceans. However, data on their trophic ecology and role in benthic–pelagic coupling and biogeochemical cycles remain limited. This study assesses the trophic ecology of Leptogorgia virgulata in the Skidaway River estuary, USA (31.9896N, 81.0242W) by analysing carbon and nitrogen isotopic signatures of its soft tissue and different-sized fractions of particulate organic matter (POM) in its environment. Samples were taken in 5 April, 2 August, and 15 October 2012 and 11 January 2013. Results support a distinct temporal shift in the diet of L. virgulata from the POM fraction <10 µm (i.e. pico- and nanoplankton) to the 10–63-µm fraction (i.e. microplankton). This trophic regime is likely associated with the natural abundance of prey items within these size classes, thus suggesting that L. virgulata may be an opportunistic feeder, and seasonal shifts in food availability in the water column affect its diet. As such small prey items affect the bioenergetics of L. virgulata, it is important to understand the implications of changes in food availability associated with environmental drivers on the physiology and population dynamics of this dominant species in the western Atlantic Ocean. 相似文献
206.
Vojtěch Ettler Martina Vítková Martin Mihaljevič Ondřej Šebek Mariana Klementová František Veselovský Pavel Vybíral Bohdan Kříbek 《Environmental geochemistry and health》2014,36(5):919-933
Metal smelting is often responsible for local contamination of environmental compartments. Dust materials escaping from the smelting facilities not only settle in the soil, but can also have direct effects on populations living close to these operations (by ingestion or inhalation). In this particular study, we investigate dusts from Cu–Co metal smelters in the Zambian Copperbelt, using a combination of mineralogical techniques (XRD, SEM/EDS, and TEM/EDS), in order to understand the solid speciation of the contaminants, as well as their bioaccessibility using in vitro tests in simulated gastric and lung fluids to assess the exposure risk for humans. The leaching of metals was mainly dependent on the contaminant mineralogy. Based on our results, a potential risk can be recognized, particularly from ingestion of the dust, with bioaccessible fractions ranging from 21 to 89 % of the total contaminant concentrations. In contrast, relatively low bioaccessible fractions were observed for simulated lung fluid extracts, with values ranging from 0.01 % (Pb) up to 16.5 % (Co) of total contaminant concentrations. Daily intakes via oral exposure, calculated for an adult (70 kg, ingestion rate 50 mg dust per day), slightly exceeded the tolerable daily intake limits for Co (1.66× for fly ash and 1.19× for slag dust) and occasionally also for Pb (1.49×, fly ash) and As (1.64×, electrostatic precipitator dust). Cobalt has been suggested as the most important pollutant, and the direct pathways of the population’s exposures to dust particles in the industrial parts of the Zambian Copperbelt should be further studied in interdisciplinary investigations. 相似文献
207.
Ofelia Morton-Bermea Omar Amador-Muñoz Lida Martínez-Trejo Elizabeth Hernández-Álvarez Laura Beramendi-Orosco María Elena García-Arreola 《Environmental geochemistry and health》2014,36(5):987-994
The increase in platinum (Pt) in the airborne particulate matter with size ≤2.5 µm (PM2.5) in urban environments may be interpreted as result of the abrasion and deterioration of automobile catalyst. Nowadays, about four million vehicles in Mexico City use catalytic converters, which means that their impact should be considered. In order to evaluate the contribution of Pt to environmental pollution of the metropolitan area of Mexico City (MAMC), airborne PM2.5 was collected at five different sites in the urban area (NW, NE, C, SW, SE) in 2011 during April (dry-warm season), August (rainy season) and December (dry-cold season). Analytical determinations were carried out using a ICP-MS with a collision cell and kinetic energy discrimination. The analytical and instrument performance was evaluated with standard road dust reference material (BCR-723). Median Pt concentration in the analyzed particulate was is 38.4 pg m?3 (minimal value 1 pg m?3 maximal value 79 pg m?3). Obtained Pt concentrations are higher than those reported for other urban areas. Spatial variation shows that SW had Pt concentration significantly higher than NW and C only. Seasonal variation shows that Pt median was higher in rainy season than in both dry seasons. A comparison of these results with previously reported data of PM10 from 1991 and 2003 in the same studied area shows a worrying increase in the concentration of Pt in the air environment of MAMC. 相似文献
208.
Dóra B. Huszár Rasmus S. Larsen Sarah Carlsen Jacobus J. Boomsma Jes Søe Pedersen 《Behavioral ecology and sociobiology》2014,68(11):1859-1870
Ant supercolonies (large networks of interconnected nests) represent the most extreme form of multi-queen breeding (polygyny) and have been found across ant lineages, usually in specific long-term stable populations. Many studies on the genetic population structure and demography of ant supercolonies have been done in recent decades, but they have lacked multicolonial control patches with separated colonies headed by a single or few queens so the origin of the supercolonial trait syndrome has remained enigmatic. Here, we set out to compare sympatric supercolonial and multicolonial patches in two natural Danish populations of the common red ant Myrmica rubra. We used DNA microsatellites to reconstruct genetic colony/population structure and obtained morphological and density measurements to estimate life history and ecology covariates. We found that supercolonies in both populations completely dominated their patches whereas colonies in multicolonial patches coexisted with other ant species. Supercolony patches had very low genetic differentiation between nests, negligible relatedness within nests, and lower inbreeding than multicolonial patches, but there were no significant morphological differences. One population also had nests that approached true outbred monogyny with larger workers and males but smaller queens than in the two other social nest types. Our results suggest that once smaller colonies start to adopt additional queens, they also gain the potential to ultimately become supercolonial when the habitat allows rapid expansion through nest budding. This is relevant for understanding obligate polygyny in ants and for appreciating how and why introduced North American populations of M. rubra have recently become invasive. 相似文献
209.
S. Kabas A. Faz J. A. Acosta J. M. Arocena R. Zornoza S. Martínez-Martínez D. M. Carmona 《Environmental geochemistry and health》2014,36(1):41-54
Poor soil fertility is often the biggest challenge to the establishment of vegetation in mine wastes deposits. We conducted field trials in the El Gorguel and El Lirio sites in SE Spain, two representative tailing ponds of similar properties except for pH, to understand the environmental and plant-relevant benefits of marble waste (MW) and pig slurry (PS) applications to mine tailings. Low pH (5.4) tailings (El Lirio) exhibit reduction of up to fourfold in bio-availability of metals as shown by the DTPA-Zn, Pb, water-soluble Zn, Pb and up to 3× for water-soluble Cd. Tailings in El Gorguel have high pH (7.4) and did not exhibit significant trends in the reductions of water-extractable Zn, Pb, Cd and Cu. Improvements to the edaphic (plant-relevant) properties of tailings after the amendments are not as sensitive to pH compared to the environmental characteristics. The two sites had increases in aggregate stability, organic matter (total N and organic C) although total N is higher in the El Gorguel (up to 212 μg N kg?1) than the El Lirio (up to 26 μg N kg?1). However, cation exchange capacities are similar in both sites at 15.2 cmol(+) kg?1. We conclude that the characteristics, especially pH, of tailing materials significantly influence the fate of metals but not improvements to plant-relevant properties such as cation exchange capacity and aggregate stability 1 year after the application of MW and PS amendments. 相似文献
210.
A. P. Rodríguez-Troncoso E. Carpizo-Ituarte D. T. Pettay M. E. Warner A. L. Cupul-Magaña 《Marine Biology》2014,161(1):131-139
Coral bleaching events are associated with abnormal increases in temperature, such as those produced during El Niño. Recently, a breakdown in the coral–dinoflagellate (genus Symbiodinium) endosymbiosis has been documented in corals exposed to anomalously cold-water temperatures associated with La Niña events. Given the ecological significance of such events, as well as the threat of global climate change, surprisingly little is known about the physiological response of corals to cold stress. This study evaluated some physiological effects of continuous temperature decline in colonies of the eastern Pacific reef-building coral Pocillopora verrucosa. Twenty days of incubation at 18.5–19.0 °C resulted in a substantial decrease in holobiont lipid and Chla content, as well as an increase in Symbiodinium density. These observations suggest a combination of symbiont acclimation due to the temperature decline and reallocation of carbon toward algal growth as opposed to translocation to the host coral. With a decreased availability of symbiont-derived carbon, the coral likely catabolized storage lipids in order to survive the stress event. Despite this stress and some tissue necrosis, no mortality was noted and corals recovered quickly when returned to the ambient temperature. As these results are in marked contrast to similar studies investigating elevated temperature on this coral from this same location, Pocillopora in the Mexican Central Pacific may be more prone to long-term damage and mortality during periods of ocean warming as opposed to ocean cooling. 相似文献