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We report the first record of the invasive freshwater jellyfish Craspedacusta sowerbii Lankester in Kralk1z1 Dam Lake,Southeastern Anatolia,Turkey.The medusa was found only in August,2008 when average surface water temperatures were 26.9℃. 相似文献
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H2S是一种剧毒、有害性气体,乌鲁木齐西山井田是我国最早发现煤层瓦斯中H2S异常的井田之一。为了新建矿井煤炭资源开采安全,基于煤田地质勘查和矿井开拓成果,分析了影响原位煤层中H2S含量的因素,探讨了H2S异常的成因。研究结果表明:1)在煤田勘探范围内(埋深浅于600m),实测H2S含量与煤层埋深、煤层瓦斯总含量、CH4、CO2、N2含量、水分含量(Mad)、灰分产率(Ad)呈负相关趋势,与全硫含量(St,d)、挥发分产率(Vdaf)呈正相关趋势;2)H2S异常的主要成因为煤层自燃、BSR、TDS、TSR混合成因及地下水的迁移。 相似文献
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Using regression model to identify and evaluate heavy metal pollution sources in an open pit coal mine area,Eastern Junggar,China 总被引：1，自引：0，他引：1
Rukeya Sawut Tashpolat Tiyip Abdugheni Abliz Nijat Kasim Ilyas Nurmemet Memet Sawut Nigara Tashpolat Arzune Ablimit 《Environmental Earth Sciences》2017,76(24):822
This study aims at identifying multi-source heavy metal pollution from natural and anthropogenic sources using a regression model, principal component analysis, and five different indices (geo-accumulation index (I geo), the modified degree of contamination, pollution load index (PLI), enrichment factor, and ecological risk factor. Results revealed that: (1) although the average concentrations of soil heavy metals (Cu, Cr, Pb, Hg, As, Zn) were generally low, Hg, As, and Cr concentrations exceeded national standard values by approximately 0.91, 1.84, and 0.91 times with maximum concentrations up to 0.41, 78.6, and 175.2 μg/g, respectively; (2) PLI results showed that the industrial park and Wucaiwan open coal mining area were the most polluted (PLI of 1.98, 1.71). The potential ecological hazards index indicated that the E i r of three heavy metals (Cu, Hg, As) in the soil were relatively high, presenting potential ecological risk factors of 74.89, 16.71, 4.15%, respectively; (3) stepwise regression model and principal component analysis suggest that Cu and Zn were primarily effected by the natural geological condition and atmospheric dust fall. Cr, Hg, Pb are mainly derived from anthropogenic sources, particularly coal mining activities and industrial sources. Results of this research have some significant implications for heavy metal pollution prevention and the sustainable development of the economy and ecology of arid regions in China. 相似文献
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