全文获取类型
收费全文 | 402篇 |
免费 | 6篇 |
专业分类
安全科学 | 16篇 |
废物处理 | 26篇 |
环保管理 | 36篇 |
综合类 | 48篇 |
基础理论 | 98篇 |
污染及防治 | 114篇 |
评价与监测 | 39篇 |
社会与环境 | 29篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 1篇 |
2022年 | 8篇 |
2021年 | 8篇 |
2020年 | 10篇 |
2019年 | 5篇 |
2018年 | 21篇 |
2017年 | 6篇 |
2016年 | 25篇 |
2015年 | 19篇 |
2014年 | 20篇 |
2013年 | 41篇 |
2012年 | 32篇 |
2011年 | 45篇 |
2010年 | 28篇 |
2009年 | 27篇 |
2008年 | 23篇 |
2007年 | 10篇 |
2006年 | 19篇 |
2005年 | 6篇 |
2004年 | 14篇 |
2003年 | 9篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
排序方式: 共有408条查询结果,搜索用时 156 毫秒
91.
The contingent valuation method (CVM) has limitations arising from the lack of a direct link between estimated willingness to pay and consumer behavior regarding the use of the good being evaluated. To estimate the total value of a resource under a capacity constraint, information on intended use is introduced as an integral part of the CVM. This combined approach allows use and non-use values to be distinguished for a sample of users and non-users. The econometric specification is applied to estimate the benefits of reducing water pollution on beaches located near an important metropolitan area of South America. 相似文献
92.
Study of metal fractionation in river sediments. A comparison between kinetic and sequential extraction procedures 总被引:6,自引:0,他引:6
Gismera MJ Lacal J da Silva P García R Teresa Sevilla M Procopio JR 《Environmental pollution (Barking, Essex : 1987)》2004,127(2):175-182
The extraction kinetic of trace metals (Cd, Cu, Pb, and Zn) in river sediments by four extraction agents was studied. As extractants ammonium acetate, acetic acid, hydroxylamine and EDTA solutions were assayed. These reagents can leach the metals more or less selectively from several metal compartments of sediments. The metal leaching kinetic model permits classification of the metal species in labile and moderately-labile ones. The combination of two or more non specific reagents permits a high characterisation of metal distribution and leachability. The results obtained with this model in four river sediments were compared with data obtained by the SM&T sequential extraction procedure, in order to characterise the chemical nature of leached metal. 相似文献
93.
Kinetics of photodegradation and ozonation of pentachlorophenol 总被引:3,自引:0,他引:3
The oxidation of 2,3,4,5,6-pentachlorophenol (PCP) has been carried out by a photodecomposition process using a polychromatic UV irradiation, and by an ozonation process. In the photodegradation process, the pH accelerated the decomposition rate and the approximate first-order rate constants were evaluated, with values between 0.16+/-0.005 min(-1) at pH=3 and 0.26+/-0.007 min(-1) at pH=9. A more rigorous kinetic study led to the determination of the quantum yields of the reaction, with values of 200+/-7x10(-3) mol/Eins for pH=3 and 22+/-1.1x10(-3) mol/Eins for pH=9. In the ozonation process, the rate constants for the reaction between ozone and PCP were determined by means of a competition kinetics, with values in the range from 0.67x10(5) to 314x10(5) l/mols. The specific rate constants for the un-dissociated and dissociated forms of PCP were also calculated. Finally, in both processes, the intermediate reaction products were identified, the most important being tetrachlorocatechol, tetrachlorohydroquinone and tetra-p-chlorobenzoquinone. Free chloride ion released, which was favored at high pHs, was also followed in both processes. 相似文献
94.
López Alonso M Benedito JL Miranda M Fernández JA Castillo C Hernández J Shore RF 《Environmental pollution (Barking, Essex : 1987)》2003,125(2):173-181
Mercury (Hg) is a highly toxic environmental contaminant and man-made emissions account for between a quarter and a third of total atmospheric levels. Point discharges, particularly coal-burning power stations, are major sources of atmospheric Hg and can result in marked spatial variation in mercury deposition and subsequent uptake by biota. The aims of this study were to quantify the extent to which major point and diffuse sources of atmospheric Hg emissions affected accumulation of Hg by biota throughout Galicia and Asturias, two of the major regions in northwest Spain. We did this by relating renal Hg concentrations in locally reared cattle (n=284) to the proximity of animals to point and diffuse sources of Hg emissions. Mercury residues in calf kidneys ranged between non-detected and 89.4 g/kg wet weight. Point discharges from coal-fired power plants in Galicia had the most dominant impact on Hg accumulation by calves in Galicia, affecting animals throughout the region and explaining some two-thirds of the variation in renal residues between animals located directly downwind from the plants. The effects of more diffuse emission sources on Hg accumulation in calves were not distinguishable in Galicia but were detected in cattle from neighbouring Asturias. The impact of both point and diffuse sources in elevating environmental levels of bioavailable Hg and subsequent accumulation by cattle extended to approximately 140-200 km downwind from source. 相似文献
95.
环境危机管理经验研究 总被引:1,自引:0,他引:1
Miranda Schreurs Robert Percival 《环境科学研究》2006,19(Z1):133-142
环境危机通常通过推动采用预防危机反复出现,并提高社会对危机事件迅速有效反应能力的措施,而成为改善环境管理的催化剂.回顾了美国、欧洲与日本的几个环境危机事例以及国家调整性政策的改变.总结出进行环境危机管理工作应该考虑:①紧急准备要求国家与地方权力机构应该通过仔细监测工业用有害化学品的使用情况、使用结果与运输情况,以及可能带来的环境影响,了解其潜在的环境灾难.要求从事可能会带来环境危机活动的责任方证明其已经制定了综合有效的应急反应计划.②排放有害物质的责任方要负责承担补救环境与人类健康损失所花费的全额成本.建立有效的责任计划可以推动对预防环境危机措施方面的投资.③发生环境危机时,采取的最基本措施是及时将有关危机性质与范围等情况通告应急反应权力机构及公众.以提高应急反应能力,保持公众的信任.④吸取经验预防环境危机事件再发生.独立调查委员会要探索发生环境事故的原因,并为预防工作提供意见或建议.⑤政府与行业有责任采取措施保护公众免受与有害物质排放和其他有害活动相关的潜在危害;在事故发生时能及时反应并使损害达到最低;对人类健康与环境造的成损害提供赔偿. 相似文献
96.
Juan C. Alonso Carlos Palacín Javier A. Alonso Carlos A. Martín 《Behavioral ecology and sociobiology》2009,63(12):1705-1715
Radio tracking of 142 males captured at 44 leks in Spain showed that partial migration of great bustard males in summer is
a widespread behaviour in many Iberian populations, in contrast to their previously assumed sedentariness. A variable number
of males migrated immediately after mating to summering areas with lower temperatures and human population densities and more
trees and rainfall levels than the breeding sites. Birds selected there fields with trees and sunflower crops which provided
shade during the hottest midday hours and protective cover against predators. Males breeding in areas with higher July temperatures
had a higher tendency to migrate, and males from hotter, southern regions migrated longer distances than those from milder,
northern regions and showed a preferred northward direction. These results confirmed various predictions from the weather
sensitivity hypothesis, suggesting that summer migration of great bustard males represents primarily an adaptation to escape
the summer heat of most breeding areas in central and southern Iberia. The hypothesis that males migrated to benefit from
higher food availability at the summering areas could not be rejected by our results. Finally, migrating males also gained
more tranquillity during the post-breeding moult due to the lower human population density at the summering areas. Summer
migration of Iberian great bustard males may thus be interpreted as a form of behavioural thermoregulation which has not been
described for other Palaearctic populations of this species or for other bird species breeding in temperate latitudes. 相似文献
97.
98.
Guiomar Rotllant Francisco Javier Moyano Mireia Andrés Alicia Estévez Manuel Díaz Enric Gisbert 《Marine Biology》2010,157(10):2215-2227
The effect of food deprivation on larval performance of the spider crab Maja brachydactyla was studied in terms of survival, moulting capacity, size, weight and enzymatic activities. Five feeding treatments that
differed in the initial age of first feeding larvae (fed from hatching, 2, 4 and 6 days post-hatching and unfed) were tested
for 20 days. Newly hatched larvae kept without food supply lasted for 10 days and did not moult; with 50% survival observed
at 6 days post-hatching. Larvae (zoea I stage) were only able to tolerate 2 days of food deprivation after the onset of exogenous
feeding without their performance being compromised. Multivariate analyses suggest that digestive enzyme activities may be
good indicators of the nutritional condition of larvae. 相似文献
99.
100.
Petra Quillfeldt Javier Martínez Janos Hennicke Katrin Ludynia Anja Gladbach Juan F. Masello Samuel Riou Santiago Merino 《Die Naturwissenschaften》2010,97(9):809-817
Whereas some bird species are heavily affected by blood parasites in the wild, others reportedly are not. Seabirds, in particular,
are often free from blood parasites, even in the presence of potential vectors. By means of polymerase chain reaction, we
amplified a DNA fragment from the cytochrome b gene to detect parasites of the genera Plasmodium, Leucocytozoon, and Haemoproteus in 14 seabird species, ranging from Antarctica to the tropical Indian Ocean. We did not detect parasites in 11 of these species,
including one Antarctic, four subantarctic, two temperate, and four tropical species. On the other hand, two subantarctic
species, thin-billed prions Pachyptila belcheri and dolphin gulls Larus scoresbii, were found infected. One of 28 thin-billed prions had a Plasmodium infection whose DNA sequence was identical to lineage P22 of Plasmodium relictum, and one of 20 dolphin gulls was infected with a Haemoproteus lineage which appears phylogenetically clustered with parasites species isolated from passeriform birds such as Haemoproteus lanii, Haemoproteus magnus, Haemoproteus fringillae, Haemoproteus sylvae, Haemoproteus payevskyi, and Haemoproteus belopolskyi. In addition, we found a high parasite prevalence in a single tropical species, the Christmas Island frigatebird Fregata andrewsi, where 56% of sampled adults were infected with Haemoproteus. The latter formed a monophyletic group that includes a Haemoproteus line from Eastern Asian black-tailed gulls Larus crassirostris. Our results are in agreement with those showing that (a) seabirds are poor in hemosporidians and (b) latitude could be a
determining factor to predict the presence of hemosporidians in birds. However, further studies should explore the relative
importance of extrinsic and intrinsic factors on parasite prevalence, in particular using phylogenetically controlled comparative
analyses, systematic sampling and screening of vectors, and within-species comparisons. 相似文献