全文获取类型
收费全文 | 6989篇 |
免费 | 577篇 |
国内免费 | 3027篇 |
专业分类
安全科学 | 201篇 |
废物处理 | 196篇 |
环保管理 | 575篇 |
综合类 | 5334篇 |
基础理论 | 2388篇 |
污染及防治 | 898篇 |
评价与监测 | 525篇 |
社会与环境 | 318篇 |
灾害及防治 | 158篇 |
出版年
2024年 | 53篇 |
2023年 | 199篇 |
2022年 | 303篇 |
2021年 | 322篇 |
2020年 | 292篇 |
2019年 | 294篇 |
2018年 | 300篇 |
2017年 | 311篇 |
2016年 | 407篇 |
2015年 | 413篇 |
2014年 | 489篇 |
2013年 | 773篇 |
2012年 | 594篇 |
2011年 | 629篇 |
2010年 | 478篇 |
2009年 | 488篇 |
2008年 | 472篇 |
2007年 | 541篇 |
2006年 | 490篇 |
2005年 | 377篇 |
2004年 | 317篇 |
2003年 | 315篇 |
2002年 | 266篇 |
2001年 | 233篇 |
2000年 | 222篇 |
1999年 | 148篇 |
1998年 | 110篇 |
1997年 | 116篇 |
1996年 | 109篇 |
1995年 | 117篇 |
1994年 | 87篇 |
1993年 | 71篇 |
1992年 | 48篇 |
1991年 | 53篇 |
1990年 | 42篇 |
1989年 | 30篇 |
1988年 | 15篇 |
1987年 | 16篇 |
1986年 | 9篇 |
1985年 | 2篇 |
1984年 | 6篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 7篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1971年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 755 毫秒
311.
312.
313.
粤北地区干旱监测及预警方法研究 总被引:2,自引:0,他引:2
从农业生产实际出发,引入能够判断作物受旱程度的毛管破裂含水量、凋萎含水量等土壤含水量指标来确定干旱指标,根据土壤水分平衡理论,建立干旱监测预警模型,利用自动站气象资料和降水趋势预报对干旱情况进行判别和分析,并采用Surfer软件对干旱情况进行直观的图形显示. 相似文献
314.
315.
Health risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China 总被引:24,自引:0,他引:24
Khan S Cao Q Zheng YM Huang YZ Zhu YG 《Environmental pollution (Barking, Essex : 1987)》2008,152(3):686-692
Consumption of food crops contaminated with heavy metals is a major food chain route for human exposure. We studied the health risks of heavy metals in contaminated food crops irrigated with wastewater. Results indicate that there is a substantial buildup of heavy metals in wastewater-irrigated soils, collected from Beijing, China. Heavy metal concentrations in plants grown in wastewater-irrigated soils were significantly higher (P相似文献
316.
Effects of three pesticides on the avoidance behavior of earthworms in laboratory tests performed under temperate and tropical conditions 总被引:2,自引:0,他引:2
Garcia M Römbke J de Brito MT Scheffczyk A 《Environmental pollution (Barking, Essex : 1987)》2008,153(2):450-456
Little research has been performed on the impact of pesticides on earthworms under tropical conditions. Taking into consideration the often-limited resources in tropical countries, simple screening tests are needed. Therefore, it was investigated whether three pesticides relevant for the Brazilian Amazon (benomyl, carbendazim, lambda-cyhalothrin) affect the avoidance behavior of the earthworm Eisenia fetida. The tests were performed for two days according to ISO guideline 17512 but were adapted to tropical conditions (i.e. test substrate, test organism and temperature). The results indicate that this test gives reproducible and reliable results. Toxicity values (NOEC, EC50) are lower than those determined in 14 day-acute mortality tests and are approximately in the same range such as those found in 56 day-chronic reproduction tests with the same earthworm species, which were performed in parallel. Therefore, the use of the earthworm avoidance tests is recommended as a screening tool for the risk assessment of pesticides. 相似文献
317.
Teuchies J de Deckere E Bervoets L Meynendonckx J van Regenmortel S Blust R Meire P 《Environmental pollution (Barking, Essex : 1987)》2008,155(1):20-30
A historical input of trace metals into tidal marshes fringing the river Scheldt may be a cause for concern. Nevertheless, the specific physicochemical form, rather than the total concentration, determines the ecotoxicological risk of metals in the soil. In this study the effect of tidal regime on the distribution of trace metals in different compartments of the soil was investigated. As, Cd, Cu and Zn concentrations in sediment, pore water and in roots were determined along a depth profile. Total sediment metal concentrations were similar at different sites, reflecting pollution history. Pore water metal concentrations were generally higher under less flooded conditions (mean is (2.32 ± 0.08) × 10−3 mg Cd L−1 and (1.53 ± 0.03) × 10−3 mg Cd L−1). Metal concentrations associated with roots (mean is 202.47 ± 2.83 mg Cd kg−1 and 69.39 ± 0.99 mg Cd kg−1) were up to 10 times higher than sediment (mean is 20.48 ± 0.19 mg Cd kg−1 and 20.42 ± 0.21 mg Cd kg−1) metal concentrations and higher under dryer conditions. Despite high metal concentrations associated with roots, the major part of the metals in the marsh soil is still associated with the sediment as the overall biomass of roots is small compared to the sediment. 相似文献
318.
Kinetic extractions to assess mobilization of Zn, Pb, Cu, and Cd in a metal-contaminated soil: EDTA vs. citrate 总被引:4,自引:0,他引:4
Labanowski J Monna F Bermond A Cambier P Fernandez C Lamy I van Oort F 《Environmental pollution (Barking, Essex : 1987)》2008,152(3):693-701
Kinetic EDTA and citrate extractions were used to mimic metal mobilization in a soil contaminated by metallurgical fallout. Modeling of metal removal rates vs. time distinguished two metal pools: readily labile (QM1) and less labile (QM2). In citrate extractions, total extractability (QM1+QM2) of Zn and Cd was proportionally higher than for Pb and Cu. Proportions of Pb and Cu extracted with EDTA were three times higher than when using citrate. We observed similar QM1/QM2 ratios for Zn and Cu regardless of the extractant, suggesting comparable binding energies to soil constituents. However, for Pb and Cd, more heterogeneous binding energies were hypothesized to explain different kinetic extraction behaviors. Proportions of citrate-labile metals were found consistent with their short-term, in-situ mobility assessed in the studied soil, i.e., metal amount released in the soil solution or extracted by cultivated plants. Kinetic EDTA extractions were hypothesized to be more predictive for long-term metal migration with depth. 相似文献
319.
Heavy metal accumulation in Littoraria scabra along polluted and pristine mangrove areas of Tanzania
The periwinkle Littoraria scabra was collected at polluted and pristine mangrove sites along the Tanzanian coastline, including Msimbazi, Mbweni (i.e. Dar es Salaam) and Kisakasaka, Nyamanzi and Maruhubi (i.e. Zanzibar). Periwinkles were morphologically characterized, sexed and their heavy metal content was determined using ICP-MS. Analysis revealed that L. scabra from polluted areas contained higher soft tissue heavy metal levels, were significantly smaller and weighed less compared to their conspecifics from the unpolluted mangroves. The current morphological observations may be explained in terms of growth and/or mortality rate differences between the polluted and non-polluted sites. Although a variety of stressors may account for these adverse morphological patterns, our data suggest a close relationship with the soft tissue heavy metal content. Compared to soft tissue heavy metal levels that were measured in L. scabra along the same area in 1998, most metals, except for arsenic, chromium and iron have decreased dramatically. 相似文献
320.
Hernández-Allica J Becerril JM Garbisu C 《Environmental pollution (Barking, Essex : 1987)》2008,152(1):32-40
A hydroponic screening method was used to identify high biomass crop plants with the ability to accumulate metals. Highest values of shoot accumulation were found in maize cv. Ranchero, rapeseed cv. Karat, and cardoon cv. Peralta for Pb (18 753 mg kg(-1)), Zn (10 916 mg kg(-1)), and Cd (242 mg kg(-1)), respectively. Subsequently, we tested the potential of these three cultivars for the phytoextraction of a metal spiked compost, finding out that, in cardoon and maize plants, increasing Zn and Cd concentrations led to lower values of root and shoot DW. By contrast, rapeseed shoot growth was not significantly affected by Cd concentration. Finally, a metal polluted soil was used to check these cultivars' phytoextraction capacity. Although the soil was phytotoxic enough to prevent the growth of cardoon and rapeseed plants, maize plants phytoextracted 3.7 mg Zn pot(-1). We concluded that the phytoextraction performance of cultivars varies depending on the screening method used. 相似文献