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351.
呼伦湖、乌梁素海和岱海是内蒙古大、中、小型湖泊的典型代表,具有重要的区域生态地位.鱼类物种多样性及其群落结构可有效指示湖泊生态系统健康,本研究为首次采用环境DNA技术探究三大湖泊间鱼类多样性及其群落特征差异,为水生态监测与管理提供数据支撑.结果表明:(1)相比传统调查,环境DNA在单点位检出的物种数量更多,是传统调查的1.25倍;(2)环境DNA技术具有一定的准确度;(3)本次环境DNA调查共检出鱼类5目10科23属27种,对呼伦湖检出18种、乌梁素海检出19种、岱海检出23种,三大湖泊共同检出鱼类12种.环境DNA技术与形态学调查可相互补充,应用于不同场景,共同服务于水生态监测与管理.环境DNA技术具备高效灵敏、低损害性、环境限制少等优势,有望成为鱼类健康评估与诊断的有力工具. 相似文献
352.
为评估广西刁江野生鱼类重金属积累特征及其健康风险,分析了广西刁江水系8种野生鱼类肌肉中铅(Pb)、镉(Cd)、铬(Cr)、砷(As)和汞(Hg)5种重金属的含量水平.利用污染指数法和目标危害系数法对其污染程度、食用安全性及健康风险进行了评价.结果表明,所有鱼类肌肉样品中Pb、Cd、Cr、As和Hg的含量范围分别为0.041~1.160、0.000 1~0.066、0.173~0.789、0.010~2.420和0.000 7~0.077 mg·kg~(-1).Pb和As的含量水平超出《食品中污染物限量》(GB 2762-2012)的限值,超标率分别为5.06%和64.56%;而Cd、Cr和Hg的含量水平未出现超标现象.污染指数结果表明:越南鱊和须鱊受到重金属严重污染;罗非鱼处于中污染水平;餐鲦、南方拟餐、鲫鱼、大眼鳜和草鱼处于轻污染水平.刁江水系8种野生鱼类对Pb、Cr和Hg的富集程度较大;肉食性和杂食性鱼类重金属含量水平高于草食性鱼类.越南鱊和须鱊复合重金属目标危害系数均大于1,这表明当地居民长期摄食越南鱊和须鱊暴露重金属存在潜在健康风险.在所有野生鱼类(南方拟餐和餐鲦除外)的复合重金属目标危害系数中,As的贡献比例最高,平均贡献率达到76.63%,说明As是主要风险元素. 相似文献
353.
转基因作物潜在的健康和环境风险一直以来颇受争议,转基因作物加工成动物饲料后可能会诱导动物产生免疫应激反应,影响动物的生长发育、繁殖等。鱼类是水生脊椎动物的代表,已广泛应用于水环境的监测,但目前转基因作物对鱼类的饲用安全性研究还相对较少。文章基于转基因作物作为鱼饲料原料对鱼类生态毒理学效应的研究现状,综述了转基因作物对鱼的生长表现、生理生化、脏器功能及发育、组织病理以及行为活动等方面的生态毒理学效应,分析了当前研究中存在的问题,并对今后的研究趋势进行了探讨。 相似文献
354.
~~广西大明山自然保护区鱼类资源调查研究@黄文$湖南省第一师范学校!湖南长沙410002
@邓学建$湖南师范大学生命科学学院动物系!湖南长沙410081~~~~~~ 相似文献
355.
J. K. Finkenbine J. W. Atwater D. S. Mavinic 《Journal of the American Water Resources Association》2000,36(5):1149-1160
ABSTRACT: Urban development has compromised the quality of physical elements offish habitat in low‐order spawning and rearing streams. In order to identify where priorities should lie in stream rehabilitation, field surveys of a number of streams were conducted near Vancouver, British Columbia. All of the streams were located in watersheds which were urbanized approximately 20 years earlier. The study watersheds ranged from 5 to 77 percent total impervious area (percent TIA). The urban streambeds were found to have less fine material and slightly higher values of intragravel dissolved oxygen than in rural streams. This improved gravel quality is attributed to the higher peak flows generated by impervious areas, and the reduced recruitment of fine material in the urban watersheds. Summer base flow was uniformly low when imperviousness was above 40 percent, evidenced by a decrease in velocity rather than water depth. Large woody debris (LWD) was scarce in all streams with > 20 percent TIA. A healthy buffer zone and abundant LWD were found to stabilize stream banks. The introduction of LWD is considered the most important strategy for stream rehabilitation. Stormwater detention ponds, in contrast, are concluded to have few hydrological benefits if constructed after a stream has reached its urban equilibrium. 相似文献
356.
Urban Land-Use Influences on Transport of Heavy Metals to Lakes and Concentrations in Fish 总被引:1,自引:0,他引:1
Water, Air, &; Soil Pollution: Focus - To investigate the urban land-useinfluences on transport of heavy metals to lakesand metal concentrations in fish liver (perch andcrucian carp), ten lakes... 相似文献
357.
John Cairns Kenneth W. Thompson J. David Landers Michael J. Mckee Albert C. Hendricks 《Journal of the American Water Resources Association》1980,16(3):421-427
ABSTRACT: Electronic modifications necessary to adapt an existing fish opercular movement monitor for use in salt water are described. Ten species of fresh and salt water fishes were tested for suitability as test organisms for future studies of pollutional effects. It was concluded that with proper tank design most species would provide useful data and that the system could be easily adapted for use in marine situations. 相似文献
358.
This paper aims to identify challenges, and threats, and further explore opportunities for a new Biodiversity Friendly Fisheries
Management Regime on the Issyk-Kul Lake in the Kyrgyz Republic. This lake is the second largest high-altitude lake in the
world providing recreational and small-scale fishing activities as well as cage culture of introduced species. The populations
of several indigenous species are seriously threatened, because many of the introduced species are potential predators. We
examine the root causes for overfishing and relationships of alien and endemic fish species in Issyk-Kul Lake and give possible
policy options that can help remediate or mitigate the biodiversity degradation. This analysis focuses on necessary legal
modifications, institutional cooperation, the protection of selected endemic fish species, control of the alien species, the
sustainable extension services and management of fish ponds. Fisheries co-management is one option to explore shared stewardship
and empowering user groups on the lake. A comprehensive fisheries management plan is also needed, in addition to immediate
action and further studies on the following wider aspects: water management/irrigation issues, water-quality assessment near
cage cultures, socio-cultural issues, resource inventory, and assessing fish biology and the lake ecosystem. 相似文献
359.
Welt M Mielke HW Gonzales C Cooper KM Batiste CG Cresswell LH Mielke PW 《Environmental geochemistry and health》2003,25(4):387-396
This research examines the pattern of sediment contamination of an urban bayou of New Orleans (formerly a natural waterway) and the potential for human exposure from consumption of fish caught in the bayou. Sediments and soils of Bayou Saint John were evaluated for lead (Pb), zinc (Zn), and cadmium (Cd). Sediment cores were collected at bridges (n = 130) and sites between the bridges (n = 303) of the bayou. In addition, soil samples (n = 66) were collected along the banks of the bayou. Sediments below the bridges contain significantly more (p-value approximately 10(-7)) Pb and Zn (medians of 241 and 230 mg kg(-1), respectively) than bayou sediments located between bridges (medians of 64 and 77 mg kg(-1), respectively). Sediments below bridges of the upper reaches of the bayou contain significantly larger amounts of metals (p < 10(-14) for Pb and Zn and p approximately 10(-8) for Cd) (medians of 329, 383 and 1.5, respectively) than sediments below bridges in the lower reaches of the bayou (medians of 43, 31 and 0.5 for Pb, Zn and Cd, respectively). Likewise, medians for sediments located between bridges contain significantly (p < 10(-14)) higher quantities of Pb, Zn and Cd (170, 203 and 1.8 mg kg(-1), respectively) in the upper bayou than Pb, Zn, and Cd (48, 32, and 0.8 mg kg(-1), respectively) in the lower reaches of the bayou. The potential risk for human exposure may be magnified by the fact that fishing generally occurs from the numerous bridges that cross the bayou. Poor and minority people do most of the fishing. Most people (87%) indicated they ate fish they caught from the Bayou. 相似文献
360.
本文对化学品登记时所要求的生物系统效应数据做解释.涉及到的测试参数包括 藻类生长抑制、蚤类急性活动抑制和繁殖及鱼类急性毒性. 相似文献