全文获取类型
收费全文 | 4299篇 |
免费 | 30篇 |
国内免费 | 10篇 |
专业分类
安全科学 | 85篇 |
废物处理 | 162篇 |
环保管理 | 205篇 |
综合类 | 1543篇 |
基础理论 | 897篇 |
环境理论 | 8篇 |
污染及防治 | 1055篇 |
评价与监测 | 204篇 |
社会与环境 | 173篇 |
灾害及防治 | 7篇 |
出版年
2022年 | 32篇 |
2019年 | 41篇 |
2018年 | 83篇 |
2017年 | 92篇 |
2016年 | 102篇 |
2015年 | 95篇 |
2014年 | 109篇 |
2013年 | 200篇 |
2012年 | 115篇 |
2011年 | 196篇 |
2010年 | 133篇 |
2009年 | 129篇 |
2008年 | 209篇 |
2007年 | 177篇 |
2006年 | 158篇 |
2005年 | 127篇 |
2004年 | 111篇 |
2003年 | 107篇 |
2002年 | 139篇 |
2001年 | 82篇 |
2000年 | 74篇 |
1999年 | 50篇 |
1998年 | 41篇 |
1997年 | 38篇 |
1996年 | 48篇 |
1995年 | 49篇 |
1994年 | 47篇 |
1993年 | 32篇 |
1992年 | 45篇 |
1991年 | 39篇 |
1990年 | 37篇 |
1989年 | 32篇 |
1981年 | 30篇 |
1976年 | 32篇 |
1973年 | 29篇 |
1968年 | 29篇 |
1967年 | 34篇 |
1966年 | 30篇 |
1965年 | 47篇 |
1964年 | 37篇 |
1963年 | 36篇 |
1962年 | 31篇 |
1961年 | 44篇 |
1960年 | 39篇 |
1959年 | 41篇 |
1958年 | 45篇 |
1957年 | 39篇 |
1956年 | 40篇 |
1955年 | 37篇 |
1954年 | 40篇 |
排序方式: 共有4339条查询结果,搜索用时 31 毫秒
901.
Improved phosphorus use efficiency in agriculture: a key requirement for its sustainable use 总被引:6,自引:0,他引:6
Mineral phosphorus (P) fertilizers processed from fossil reserves have enhanced food production over the past 50 years and, hence, the welfare of billions of people. Fertilizer P has, however, not only been used to lift the fertility level of formerly poor soils, but also allowed people to neglect the reuse of P that humans ingest in the form of food and excrete again as faeces and urine and also in other organic wastes. Consequently, P mainly moves in a linear direction from mines to distant locations for crop production, processing and consumption, where a large fraction eventually may become either agronomically inactive due to over-application, unsuitable for recycling due to fixation, contamination or dilution, and harmful as a polluting agent of surface water. This type of P use is not sustainable because fossil phosphate rock reserves are finite. Once the high quality phosphate rock reserves become depleted, too little P will be available for the soils of food-producing regions that still require P supplements to facilitate efficient utilization of resources other than P, including other nutrients. The paper shows that the amounts of P applied in agriculture could be considerably smaller by optimizing land use, improvement of fertilizer recommendations and application techniques, modified livestock diets, and adjustment of livestock densities to available land. Such a concerted set of measures is expected to reduce the use of P in agriculture whilst maintaining crop yields and minimizing the environmental impact of P losses. The paper also argues that compensation of the P exported from farms should eventually be fully based on P recovered from ‘wastes’, the recycling of which should be stimulated by policy measures. 相似文献
902.
Biosensors for detection of mercury in contaminated soils 总被引:1,自引:0,他引:1
Bontidean I Mortari A Leth S Brown NL Karlson U Larsen MM Vangronsveld J Corbisier P Csöregi E 《Environmental pollution (Barking, Essex : 1987)》2004,131(2):255-262
Biosensors based on whole bacterial cells and on bacterial heavy metal binding protein were used to determine the mercury concentration in soil. The soil samples were collected in a vegetable garden accidentally contaminated with elemental mercury 25 years earlier. Bioavailable mercury was measured using different sensors: a protein-based biosensor, a whole bacterial cell based biosensor, and a plant sensor, i.e. morphological and biochemical responses in primary leaves and roots of bean seedlings grown in the mercury-contaminated soil. For comparison the total mercury concentration of the soil samples was determined by AAS. Whole bacterial cell and protein-based biosensors gave accurate responses proportional to the total amount of mercury in the soil samples. On the contrary, plant sensors were found to be less useful indicators of soil mercury contamination, as determined by plant biomass, mercury content of primary leaves and enzyme activities. 相似文献
903.
Götz R Bauer OH Friesel P Herrmann T Jantzen E Kutzke M Lauer R Paepke O Roch K Rohweder U Schwartz R Sievers S Stachel B 《Chemosphere》2007,67(3):592-603
Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and other organic micropollutants were determined in dated sediment/soil cores collected from the flood-plain of the river Elbe near Pevestorf (PT), approximately 125 km upstream of Hamburg, and Heuckenlock (HL) in southeast of Hamburg. Concentrations of PCDD/Fs peaked sharply at PT in the 1950s and at HL at the end of the 1940s. Cluster analyses provide evidence that the region of Bitterfeld-Wolfen (about 350-400 km upstream of Hamburg) could be the source of the PCDD/F contamination existing in the cores PT and HL since the 1940s. Obviously it is caused by sediments of the river Elbe of a similar composition. Whereas the PCDD/Fs, HCHs (hexacyclohexane isomers), DDX (DDT, DDD, DDE), and tetrachlorinated ethers in PT and HL presumably originated predominantly from the Bitterfeld-Wolfen region, organotin compounds in HL and dichlorinated haloethers in HL during the 1940s and 1950s can probably largely be attributed to emissions from the Hamburg region. Although they are separated by a large distance, in both sediment cores PT and HL concentrations and composition patterns of most organic micropollutants analyzed widely match. Inductively it can be concluded that similar contaminations will be found in many of the river bank soils between the Bitterfeld-Wolfen region and Hamburg. Excavation of top soils may uncover highly contaminated materials. Since the dated sediment cores show the variation in contaminants in the Elbe sediments over a defined time period, it is possible to make an approximate assessment of the actual degree of contamination to be expected in areas where in previous decades contaminated dredged sediments from the Elbe and from the Port of Hamburg have been deposited on land and used for building plots or for agricultural purposes. 相似文献
904.
van den Bergh Thijs Körner Christian Hiltbrunner Erika 《Regional Environmental Change》2018,18(5):1375-1385
Regional Environmental Change - Shrub encroachment is one of the main consequences of abandonment of montane grassland. Higher surface roughness of shrubs leads to stronger aerodynamic coupling.... 相似文献
905.
Marmett Bruna Carvalho Roseana Böek Dorneles Gilson Pires da Silva Igor Martins Romão Pedro Roosevelt Torres Nunes Ramiro Barcos Rhoden Cláudia Ramos 《Environmental science and pollution research international》2020,27(31):39019-39028
Environmental Science and Pollution Research - Obesity and physical inactivity threaten human health, and both could be solved with exercise. However, a higher amount of pollutants is inhaled... 相似文献
906.
Umar Ibrahim Khalil Nourani Vahid Gökçekuş Hüseyin 《Environmental science and pollution research international》2021,28(36):49663-49677
Environmental Science and Pollution Research - Accuracy in the prediction of the particulate matter (PM2.5 and PM10) concentration in the atmosphere is essential for both its monitoring and... 相似文献
907.
908.
909.
910.