全文获取类型
收费全文 | 2929篇 |
免费 | 247篇 |
国内免费 | 701篇 |
专业分类
安全科学 | 596篇 |
废物处理 | 66篇 |
环保管理 | 391篇 |
综合类 | 1642篇 |
基础理论 | 501篇 |
污染及防治 | 284篇 |
评价与监测 | 113篇 |
社会与环境 | 181篇 |
灾害及防治 | 103篇 |
出版年
2024年 | 11篇 |
2023年 | 33篇 |
2022年 | 89篇 |
2021年 | 111篇 |
2020年 | 113篇 |
2019年 | 116篇 |
2018年 | 86篇 |
2017年 | 114篇 |
2016年 | 147篇 |
2015年 | 148篇 |
2014年 | 181篇 |
2013年 | 262篇 |
2012年 | 266篇 |
2011年 | 274篇 |
2010年 | 195篇 |
2009年 | 217篇 |
2008年 | 132篇 |
2007年 | 227篇 |
2006年 | 200篇 |
2005年 | 168篇 |
2004年 | 165篇 |
2003年 | 125篇 |
2002年 | 89篇 |
2001年 | 78篇 |
2000年 | 59篇 |
1999年 | 65篇 |
1998年 | 39篇 |
1997年 | 33篇 |
1996年 | 29篇 |
1995年 | 19篇 |
1994年 | 22篇 |
1993年 | 13篇 |
1992年 | 12篇 |
1991年 | 13篇 |
1990年 | 8篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有3877条查询结果,搜索用时 171 毫秒
991.
F. Rigas R. Marchant V. Dritsa E. Kapsanaki-Gotsi Z. Gonou-Zagou E. J. Avramides 《Water, Air, & Soil Pollution: Focus》2003,3(3):201-210
Many papers have shown that white rot fungi can degrade aromatic pollutants under laboratory conditions, but few report field scale trials. Here we report the first steps in the development of a remediation system for Greek conditions. A review of the available organochlorine compound pollution information in Greece is presented. White rot fungi isolated from sites in Greece have been screened for growth rate and ligninolytic activity, using decolourisation of the dye Poly R-478 as an indicator of enzyme activity. Use of white rot fungi under field conditions in Greece will require bioaugmentation to be effective at high temperatures and low water activity for much of the year. The most potent strains have been selected under a range of conditions and have been challenged with priority pollutants to determine their degradative ability under laboratory conditions and subsequently ex situ in soil. 相似文献
992.
Soils in the Mediterranean area are very prone to erosion due to the loss of organic matter and the consequent lack of protective vegetation. In this experiment a Mediterranean degraded soil with a 15% slope was amended at a rate of 250 t ha–1 wet weight with sewage sludge and with a mixture of sewage sludge and barley straw (70% carbon from sewage sludge and 30% from the straw) in order to study their influence on soil structure recovery and hence the soilss resistance to erosion processes. Both types of organic amendment led to an improvement in several soil properties (physical, biological, and microbiological) as a result of the spontaneous growth plant covering that became evident three months after amendment. This vegetation remained throughout the two years of the experiment and prevented the water erosion processes that normally precede soil degradation. Amendment by sewage sludge alone reduced soil loss by 80% compared with the control soil, while the mixture that included both sewage sludge and barley straw reduced losses by 84%, both reducing runoff by 57%. The amended soils showed increases in the percentage of stable aggregates, the levels of the total and water-soluble C fractions, microbial biomass C, basal respiration, and the activity of the different enzymes involved in the biogeochemical cycles of C, N, and P. The results confirm the usefulness of sewage sludge as an organic amendment for recovering damaged soils. 相似文献
993.
Habitat function of agricultural soils as affected by heavy metals and polycyclic aromatic hydrocarbons contamination 总被引:20,自引:0,他引:20
Ecotoxic activity of soils polluted with polycyclic aromatic hydrocarbon (PAH) and heavy metals (HM) was evaluated in pot and laboratory experiments. Plants and soil microorganisms were chosen as test organisms and six different soil materials were used in the study. The applied levels of HM and PAH were aimed to reflect environmental conditions in the "worst case" situation. Zn(2+), Pb(2+) and Cd(2+) were introduced to the soils as an aqueous solution of the mixture of salts at the concentrations corresponding to 1000, 500 and 3 mg kg(-1), respectively. Mixture of four PAH compounds (flourene, anthracene, pyrene and chrysene) as a CH(2)Cl(2) solution was applied at levels of 10-100 mg summation operator 4PAH kg(-1). Population and activity of soil microflora was evaluated as measured of total bacteria counts, intensity of respiration and enzyme activity (dehydrogenases and phosphatases). Effect on plants was evaluated on the base of the growth (plant at an early stage of their development) and yield (mature plant) measurements. The results indicate that combined effect of PAH and heavy metals on soil microorganisms activity and on some plants at an early stage of their development can be stronger than in soils amended with HM or PAH separately. Reaction of tested organisms was related to soil properties, PAH concentration, time and plant species. Mature plants (maize) were insensitive to the applied levels of both group of contaminants. 相似文献
994.
Gongal'skii K. B. Pokarzhevskii A. D. Savin F. A. Filimonova Zh. V. 《Russian Journal of Ecology》2003,34(6):395-404
The mode of spatial distribution of soil animals and their trophic activity was studied in the sod-podzolic soil under a spruce forest. At the test point level, no apparent relationship between the distribution of soil animals and physicochemical characteristics of the soil was observed. The patterns of distribution of detritophages and the trophic activity (measured using the bait-lamina test) were similar. The perforation of laminae in the bait-lamina test resulted from the trophic activity of both micro- and mesofauna. 相似文献
995.
楚雄市农村能源建设的生态经济效益分析 总被引:1,自引:0,他引:1
通过对楚雄市2002年农村能源现状及2002-2010年农村生活用能源建设规划分析,对2005年、2010年能源结构及生态环境效益进行了定量分析。经过8年农村能源建设,完全可以实现能源结构优化。环境、经济效益非常显著。 相似文献
996.
通过对205个投资额在100万元以下小型建设项目环境影响评价报告的调查,对比建设项目环保审批6项原则,发现该类建设项目环境影响评价报告中存在报告降级编写、内容不完整、结论模糊等问题,据此提出了提高报告质量的措施、建议[1]。 相似文献
997.
Impacts of newly added organic carbon (C) and inorganic nitrogen (N) on the microbial utilization of soil organic matter are important in determining the future C balance of terrestrial ecosystems. We examined microbial responses to cellulose and ammonium nitrate additions in three soils with very different C and N availability. These soils included an organic soil( 14.2% total organic C, with extremely high extractable N and low labile C), a forest soi1(4.7% total organic C, with high labile C and extremely low extractable N), and a grassland soil(1.6% total organic C, with low extractable N and labile C). While cellulose addition alone significantly enhanced microbial respiration and biomass C and N in the organic and grassland soils, it accelerated only the microbial respiration in the highly-N limited forest soil. These results indicated that when N was not limited, C addition enhanced soil respiration by stimulating both microbial growth and their metabolic activity, New C inputs lead to elevated C release in all three soils, and the magnitude of the enhancement was higher in the organic and grassland soils than the forest soil. The addition of cellulose plus N to the forest and grassland soils initially increased the microbial biomass and respiration rates, but decreased the rates as time progressed. Compared to cellulose addition alone, cellulose plus N additions increased the total C-released in the grassland soil, but not in the forest soil. The enhancement of total C- released induced by C and N addition was less than 50% of the added-C in the forest soil after 96 d of incubation, in contrast to 87.5% and 89.0% in the organic and grassland soils. These results indicate that indigenous soil C and N availability substantially impacts the allocation of organic C for microbial biomass growth and/or respiration, potentially regulating the turnover rates of the new organic C inputs. 相似文献
998.
999.
1000.
建筑施工振动环境影响评价 总被引:4,自引:0,他引:4
讨论了建筑施工振动特点.提出在编制施工计划的同时编制预防建设施工振动的规划.推荐环境振动的预测方法.认为对于建筑施工振动进行环境影响评价是非常重要的. 相似文献