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121.
William A. Jury Gideon Sinai Lewis H. Stolzy 《Journal of the American Water Resources Association》1979,15(5):1444-1458
ABSTRACT: Electric generation facility water requirement will increase substantially in the future in the Western United States because new power plants are to be constructed at inland sites rather than on the coast. At the inland locations, power plants will have to compete with agriculture and public users for fresh water supplies, and will be constrained by environmental legislation to dispose of cooling waste water in lined evaporation ponds. The various options for power plant cooling are analyzed in respect to cost, water consumption, and environmental hazard, and also in respect to their compatibility with existing state and federal regulations. Several proposals for balancing the water requirements of various users in water-scarce areas are reviewed and criticized. 相似文献
122.
Repulsion of green sunfish by certain chemicals 总被引:2,自引:0,他引:2
123.
M. L. Mallory A. J. Gaston M. R. Forbes H. G. Gilchrist B. Cheney S. Lewis P. M. Thompson 《Marine Biology》2008,154(6):1031-1040
Variation in the timing and abundance of marine food resources is known to affect the breeding behaviour of many seabirds,
constraining our understanding of the extent to which these behaviours vary in different parts of a species’ range. We studied
incubation shifts of northern fulmars (Fulmarus glacialis) breeding at two colonies in Arctic Canada (High Arctic oceanographic zone) and one colony in the UK (Boreal oceanographic
zone) between 2001 and 2005. Fulmars in Arctic Canada had longer incubation shifts than previously reported at more southern
colonies, presumably because marine productivity is lower early in the breeding season in the Arctic. Shift durations were
particularly long at one colony in years with abnormally late, extensive sea-ice cover, although at the other Arctic colony,
where sea-ice cover is predictably late every year, the duration of shifts was shorter than expected. At the Boreal colony,
incubation shifts were much longer than expected, similar to Arctic colonies, and likely attributable to poor marine food
supplies in the North Sea in recent years. Collectively, our data suggest that fulmars can adjust their incubation rhythm
to compensate for poor marine feeding conditions, although this may incur a cost to body condition or reproductive success. 相似文献
124.
Dargie Greta C. Lawson Ian T. Rayden Tim J. Miles Lera Mitchard Edward T. A. Page Susan E. Bocko Yannick E. Ifo Suspense A. Lewis Simon L. 《Mitigation and Adaptation Strategies for Global Change》2019,24(4):669-686
Mitigation and Adaptation Strategies for Global Change - The recent publication of the first spatially explicit map of peatlands in the Cuvette Centrale, central Congo Basin, reveals it to be the... 相似文献
125.
Burwell RW Beasley JS Gaston LA Borst SM Sheffield RE Strahan RE Munshaw GC 《Journal of environmental quality》2011,40(4):1241-1248
Nutrient and sediment runoff from newly constructed levee embankments pose a threat to water quality during soft armor vegetation establishment. Research was initiated in 2008 and 2009 to evaluate the effect of bermudagrass ( L.) coverage and N source on nutrient and sediment runoff from levee embankments during establishment. Bermudagrass plots were seeded at 195.3 kg pure live seed ha and fertilized at 50 kg N ha using a water-soluble N source, urea or NH-NO, or slow-release N source, S-coated urea (SCU) or urea formaldehyde (UF), with controls unfertilized. Vegetative cover percentage, time until the onset of runoff, runoff volume, and total solids (TS), NO-N, and NH-N concentrations were measured from simulated and natural rainfall events for 70 d in 2008 and 56 d in 2009. Bermudagrass at 90% grass cover delayed the onset of runoff an additional 441 to 538 s and reduced runoff volumes 74 to 84% of that exhibited at 10% grass cover. Nitrogen fertilizers did not accelerate bermudagrass growth sufficiently, however, to reduce TS loading compared with unfertilized bermudagrass in either year of the study. The application of urea and SCU resulted in cumulative N losses of 2.45 and 3.13 kg ha compared with 1.59 kg ha from the unfertilized bermudagrass in 2008, and 1.73 kg ha from NH-NO vs. 0.24 kg ha from controls in 2009. Only UF increased bermudagrass establishment without increasing cumulative N losses compared with unfertilized bermudagrass. Therefore, the benefit of greater erosion and runoff resistance expected from N-accelerated vegetative growth did not occur but had the unintended consequence of higher N losses when water-soluble N and SCU fertilizers were applied. 相似文献
126.
Mapping socio-economic scenarios of land cover change: a GIS method to enable ecosystem service modelling 总被引:3,自引:0,他引:3
Swetnam RD Fisher B Mbilinyi BP Munishi PK Willcock S Ricketts T Mwakalila S Balmford A Burgess ND Marshall AR Lewis SL 《Journal of environmental management》2011,92(3):563-574
We present a GIS method to interpret qualitatively expressed socio-economic scenarios in quantitative map-based terms. (i) We built scenarios using local stakeholders and experts to define how major land cover classes may change under different sets of drivers; (ii) we formalized these as spatially explicit rules, for example agriculture can only occur on certain soil types; (iii) we created a future land cover map which can then be used to model ecosystem services. We illustrate this for carbon storage in the Eastern Arc Mountains of Tanzania using two scenarios: the first based on sustainable development, the second based on 'business as usual' with continued forest-woodland degradation and poor protection of existing forest reserves. Between 2000 and 2025 4% of carbon stocks were lost under the first scenario compared to a loss of 41% of carbon stocks under the second scenario. Quantifying the impacts of differing future scenarios using the method we document here will be important if payments for ecosystem services are to be used to change policy in order to maintain critical ecosystem services. 相似文献
127.
128.
Significance of mangrove–mudflat boundaries as nursery grounds for the mud crab, Scylla paramamosain
Fisheries managers frequently try to protect juveniles in order to preserve stocks. Juveniles can be protected by either implementing changes designed to avoid catching immature animals (e.g. increasing mesh size or altering fishing techniques) or protecting nursery grounds. To prevent the capture of immature animals, an estimate of size at maturity is required as well as a knowledge of both fishing methods and the exact location of the nursery grounds. Strong demand for juvenile mud crabs to stock aquaculture ponds has resulted in development of fisheries targeting crabs of all sizes from instar 1 to mature individuals. Using five different fishing methods, different stages in the life cycle of Scylla paramamosain were followed for a period of 16 months in an estuarine population in the Mekong Delta, Vietnam. Mangrove habitat utilisation begins when crabs settle out from the plankton at instar 1 [modal internal carapace width (ICW), 0.5 cm] amongst the pneumatophores at the mangrove fringe. Increasingly larger crabs were found deeper into the mangrove but they were still living on the surface (modal ICW size class, 1.5 cm). As their size increases, the crabs either dig burrows (modal ICW size class, 4.5 cm) or they live in the sub-tidal zone, migrating into the mangrove with each tide to feed (modal ICW size class, 4.5 cm). Larger crabs were caught offshore (modal ICW size class, 12.5 cm) where females accounted for 60% of the catch although of these, only 63% were mature. Recruitment of early instars was continuous but peaked in December to February. Subsequent peaks in the catch rates of larger size classes indicated the development of a single cohort with an estimated growth rate of 2.0 cm ICW per month. On the basis of abdominal width, females were estimated to mature at 10.2 cm ICW although at 9.7 cm ICW, 50% of females had disengaged abdomens. Abdominal disengagement occurred in males at the slightly smaller size of 9.1 cm ICW. Allometric relationships between chela height and carapace width suggested 50% of males acquire mature chelae at 10.2 cm ICW. These results demonstrate the close linkage between early life stages of S. paramamosain and certain specific niches within mangrove habitats, with the main adult population found to be living sub-tidally at some distance from the mouth of the estuary. The study also highlights the special importance of the mangrove fringe, the border between the mangrove forest and the sea, an area which is particularly vulnerable to physical and anthropogenic impacts. 相似文献
129.
130.