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651.
为评价东江干流(惠州段)鱼类多样性,并监测其水质变化状况,根据该河段鱼类的调查资料及历史数据,编制了鱼类名录,并计算了鱼类平均分类差异指数和G-F多样性测度指数.结果显示,东江干流(惠州段)共记录近30多年来鱼类11目,29科,77属,94种,鲤形目鱼类占绝对优势;从物种水平看,研究的4个时间段鱼类物种多样性由大到小排序为 、 、 和 ;从科属水平看,鱼类物种多样性由1981~1983向2005~2007减小,再向2007~2010增加,最后向2011~2012减小.其中,1981~1983的多样性最高,2011~2012的多样性最低.平均分类差异指数与G-F多样性测度指数均适宜于东江干流(惠州段)鱼类物种多样性研究. 相似文献
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鱼类的退化受到不同类型环境因子的影响,为制定更合理的鱼类保护计划,本研究采用了非度量多维标度法(NMS)研究了太子河流域不同尺度环境因子对鱼类空间分布的影响.鱼类聚类结果发现太子河流域鱼类可分为3种分布类型区,即上游森林及支流源头区、中游山地区和下游平原区.NMS分析表明太子河流域鱼类空间分布受到流域、河段和微生境这3种尺度上环境因子的影响,海拔、河流等级和土地利用在流域尺度上对鱼类分布表现出显著影响,速度与深度结合等级、栖境复杂性等级和电导率等因子在河段尺度上表现出显著作用,底质等级是在微生境尺度上具有显著作用.因此,在流域鱼类保护管理中应考虑不同尺度上环境因子的影响. 相似文献
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金鱼(Carassius auratus L.)对水中游离态铅的吸收积累及鳃分泌粘液的自身保护作用 总被引:9,自引:0,他引:9
研究了金鱼(CarassiusauratusL.)在铅暴露实验中的铅吸收过程及鱼鳃分泌物的自身保护作用、水相Pb2+的鳃吸收机理以及分泌粘液对铅的络合作用。结果表明,金鱼因铅暴露导致粘液分泌量增加。结合到鳃上的铅与水相Pb2+活度关系可用Langmuir吸附等温式表述。据此估算的最大结合量为0.9424mmol/kg(干重).非常接近1的Hill常数(1.012)说明金鱼鳃上仅有一种类型的Pb2+结合位点。平均每尾金鱼鳃上Pb2+的结合位点数达1.62×10-5m/mol,结合的条件稳定常数(logKPb-鳃)为4.8.血液铅含量与鳃铅含量间呈显著线性关系。金鱼吸收Pb2+的主要过程为:Pb2+结合到鳃上,其后被动扩散或载体转运穿过鳃上皮,进入血液循环。 相似文献
657.
Vikas Pandey Zeba Usmani Avantika Chandra Rohit Kumar Mishra 《Chemistry and Ecology》2017,33(8):777-794
Ten sampling points were selected in Kanhan River, situated near the ash dump sites of Koradi Thermal Power Plant, Nagpur. The leaching of trace elements from fly ash dumps was experimentally determined by acid digestion, batch leaching and toxicity characteristic leaching procedure tests. Elemental concentrations in river water, sediment, plankton and five commonly prevailing fish species (Catla catla, Labeo bata, Cyprinus carpio, Cirrhinus reba, Puntius ticto) were determined using a Flame Atomic Absorption Spectrophotometer during the pre-monsoon and post-monsoon seasons. Metal concentrations (Cr, Mn, Zn, Cu, Fe, Ni, Cu and Pb) in river water were higher during the pre-monsoon season compared to the post-monsoon season. Zn (30.65?mg/kg) was observed to be the most predominant metal in plankton during the pre-monsoon season while, during the post-monsoon season, Fe (21.19?mg/kg) showed the maximum concentration. Muscles of C. catla had metal concentrations (Cr, Mn, Zn, Fe, Cu and Pb) above the permissible limits of Food and Agricultural Organization (FAO 1983) during the pre-monsoon season. Bioaccumulation factor (BAF) was found highest for Cr (37.5) in muscles of C. catla during the pre-monsoon season, while BAF was observed to be maximum in L. bata for Cu (28.09), which may be detrimental for human consumption. 相似文献
658.
Ayşe N. Kiraççakali 《Chemistry and Ecology》2020,36(7):651-662
ABSTRACT Deltamethrin is a widely used pyrethroits worldwide. Although the chemical is used to combat insects, it has effects on other non-target organisms. Deltamethrin is extensively used in agriculture, animal husbandry, and domestic areas in the Lake Van basin. The aim of this study was to determine the cytotoxic, genotoxic, and oxidative damage from deltamethrin on the primary hepatocyte culture of Lake Van fish (Alburnus tarichi). In this study, the toxic effects of different concentrations (0.01, 0.1, 1, and 10?µM) of deltamethrin in the primary hepatocyte culture of Lake Van fish were investigated via liver enzymes aspartase aminotransferase (AST) and alanine aminotransferase (ALT), and the total antioxidant status (TAS), total oxidant status (TOS), lipid peroxidation (MDA), and DNA damage (8-OHdG). Deltamethrin caused an increase in the AST and ALT levels dependent on the dosage and time. The TAS and TOS levels increased at the end of 24?h and there was no difference at the end of 48?h. Deltamethrin did not affect the MDA level, but increased the 8-OHdG (P?<?0.05). In conclusion, it can be said that high doses of deltamethrin (1 and 10?µM) have a toxic effect on the primary hepatocyte culture of Lake Van fish. 相似文献
659.
Conservation and Community Benefits from Traditional Coral Reef Management at Ahus Island, Papua New Guinea 总被引:6,自引:0,他引:6
Abstract: We investigated traditional coral reef management practices at Ahus Island, Manus Province, Papua New Guinea, to evaluate their social role in the community and potential to conserve reef ecosystems. For generations, Ahus Islanders have prohibited spear and net fishing within six delineated areas of their reef lagoon. One to three times per year, fish are briefly harvested from the restricted areas to provide food for ceremonial occasions. Underwater visual censuses of fishes revealed a significantly greater biomass and average size of target species within the restricted areas (205 kg/ha ± 20 [SE]; 102 mm TL [total length]± 0.7) compared with areas without fishing restrictions (127 kg/ha ± 13 SE; 85 mm TL ± 0.7). We estimated the biomass of fish removed during one of the harvest events was 5 to 10% of the available biomass within the restricted area, and in underwater visual surveys conducted before and after a harvesting event we detected no effect of harvesting on fish stocks. Compliance with the fishing restriction is attributed to its perceived legitimacy, its ability to provide the community with direct and indirect benefits, and its reflection of local socioeconomic circumstances. Limited-take closure systems that can serve the needs of a community may provide a viable conservation alternative in situations where compliance with fully closed protected-area regulations is low and resources for proper enforcement are untenable. 相似文献
660.
鱼贝植物组合对上海白莲泾生态修复效应研究 总被引:2,自引:0,他引:2
将鱼、贝、植物组合成3种浮岛生态系统,对上海市黄浦江支流白莲泾污染治理和生态修复,效果明显。结果表明:银纹金线蒲+鲢鳙鱼+三角帆蚌组合对总氮去除率60.7%,总磷去除率43.7%,高锰酸盐去除率35.0%,叶绿素-a降低38.2%;血草+鲢鳙鱼+三角帆蚌组合对总氮去除率55.2%,总磷去除率37.2%,高锰酸盐指数去除率42.5%,叶绿素-a降低44.3%;菖蒲+鲢鳙鱼+三角帆蚌组合对总氮去除率55.1%,总磷去除率29.7%,高锰酸盐指数去除率28.3%,叶绿素-a降低26.0%。总体上,3种浮岛生态系统能将水体总磷从Ⅲ类达到至Ⅱ类;总氮从劣Ⅴ类达到至Ⅳ类;高锰酸盐指数从Ⅳ类达到至Ⅲ类。鱼、贝、植物组合的浮岛生态系统生态效应优于单一生物因子的生态效应,该系统内生物多样性较丰富,生长良好,生态景观性明显。 相似文献