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961.
中国一半的煤炭生产能力集中于生态脆弱的黄土高原,采矿活动进一步加剧了当地生态环境恶化,尤其是土壤退化.微生物是土壤物质转化的动力,对外界干扰十分敏感,厘清其变化对生态恢复和治理尤为重要.为此,本研究以黄土高原大柳塔煤矿及黑岱沟煤矿为对象,利用高通量测序技术和分子生态网络分析方法,揭示土壤细菌群落多样性及不同活动影响下土壤细菌群落之间的联系与差异.结果表明,不同活动对土壤理化性状影响显著,塌陷区有机质、速效磷、速效钾呈显著性下降(P0.05),复垦区土壤有机质、水分、pH和电导率则显著增加(P0.05),塌陷对土壤理化性状产生了抑制作用,复垦呈现促进作用.不同活动对土壤细菌群落产生不同的影响,塌陷区多样性指数降低了约20%,复垦则多样性指数增加了63%,但塌陷区、复垦区优势菌门保持一致.不同活动对土壤细菌分子生态网络的影响迥异:塌陷后分子生态网络趋于复杂,网络连接数及互作关系明显增强;复垦后则生态网络模块增加,模块内部趋于简单.为应对地表塌陷和土地复垦,土壤细菌往往改变菌种间关系作适应性变化.塌陷更多地促进相互合作以适应养分的贫瘠,复垦则促进模块数增加并趋于合作以获取更多的资源. 相似文献
962.
利用草酸钴废料协同浸出水钴矿中的钴和铜,考察了工艺条件对浸出率的影响,并推荐了一种二段浸出及后续生产草酸钴的工艺流程。实验结果表明,在草酸钴废料与水钴矿的质量比为20%、反应时间为120 min、反应温度为85 ℃、初始H2SO4浓度为1.00 mol/L、液固比为4 mL/g的最佳工艺条件下,钴和铜的浸出率分别达到98.82%和96.24%。该工艺应用于水钴矿的还原浸出,在回收利用草酸钴废料的同时,降低了还原剂的消耗,且对浸出液后续处理工艺无影响。 相似文献
963.
Minghong Wu Jiajia Xiang Fenfen Chen Cao Fu Gang Xu 《Environmental science and pollution research international》2017,24(25):20291-20299
Antidepressants are gaining public attention because of increasing reports of their occurrence in environment and their potential impact on ecosystems and human health. Continuous input of pharmaceuticals into rivers, through psychiatric hospital or wastewater treatment plant (WWTPs) effluent, may cause adverse effects on the aquatic ecosystems of the receiving water bodies. This work investigates the occurrence and sources of 8 antidepressants in main stream and tributaries of Huangpu River in Shanghai. The detected concentrations of the selected antidepressants ranged from low nanogram per liter to 42.9 ng L?1 (fluoxetine) in main stream and ranged from low nanogram per liter to 33.7 ng L?1 (fluoxetine) in tributaries. To study the effect of hospital or wastewater treatment plants (WWTPs) on environment, the upstream and downstream samples were analyzed. Generally, antidepressants had greater concentrations in downstream than that in upstream of the WWTPs or hospitals. It is suggesting that WWTPs and hospitals may introduce pollution into water environment. A preliminary risk assessment was conducted: none of the eight target compounds yielded risk quotient (RQ) values more than 0.1, thus indicating that no adverse effect is expected in water environment. These results will provide background data for future antidepressants pollution control and management in Shanghai, China. 相似文献
964.
965.
卡马西平在污水和水环境中广泛存在,且对水生生态系统安全构成风险,因此成为目前研究较多的药品之一。以北京清河再生水厂为例,研究"超滤—臭氧氧化—氯消毒"处理工艺中卡马西平的去除特性,并针对臭氧氧化和氯消毒工艺建立模拟卡马西平去除过程的机理模型。同时,利用美国环境保护署ECOTOX数据库,获取卡马西平对北京市水生生物物种的毒性数据,并基于毒性数据建立物种敏感度分布(species sensitivity distribution,SSD)模型,评价再生水厂出水补给地表水体时卡马西平产生的生态风险。臭氧氧化和氯消毒模型对卡马西平、总有机碳、氨氮等指标的模拟误差总体低于20%,模型的灵敏参数均可以被较好地识别,且其不确定性显著下降。对比7种SSD模型发现,对数正态分布和对数Logistic分布模型较好地拟合了北京市6个物种的卡马西平毒性数据,二者预测得到的总体生态风险期望值分别为7.4%和8.5%。 相似文献
966.
物种敏感度分布(SSD)方法在农药环境风险评估中的应用 总被引:1,自引:0,他引:1
物种敏感度分布法(Species Sensitive Distribution,SSD)能够依据不同物种对农药等胁迫因素的敏感度服从一定的累积概率分布,以统计形式将多种非靶标物种的实验室数据进行汇总分析,获得物种对农药的敏感度差异,作为效应评估指标应用于农药风险评估。本文综述了SSD概念、方法原理、国内外研究和应用进展,并以毒死蜱为例进行了数据分析。由此建议继续关注国际上对SSD及更复杂模型模拟研究进展,以便应用于我国农药环境风险评估,推动我国农药管理的持续发展。 相似文献
967.
Jun-juan Shao Cheng-bin Liu Qing-hua Zhang Jian-jie Fu Rui-qiang Yang Jian-bo Shi Yong Cai Gui-bin Jiang 《Environmental geochemistry and health》2017,39(3):475-482
The accumulation and species of mercury (Hg) in mosses and lichens collected from high-altitude Tibetan Plateau were studied. The altitudes of the sampling sites spanned from 1983 to 5147 m, and a total of 130 mosses and 52 lichens were analyzed. The total mercury (THg) contents in mosses and lichens were in the ranges of 13.1–273.0 and 20.2–345.9 ng/g, respectively. The average ratios of methylmercury (MeHg) in THg in mosses and lichens were 2.4 % (0.3–11.1 %) and 2.7 % (0.4–9.6 %), respectively, which were higher than those values reported in other regions. The contents of THg in both mosses and lichens were not correlated with the THg in soils (p > 0.05). The lipid contents displayed a significantly positive correlation with concentrations of MeHg in mosses (r = 0.461, p < 0.01, n = 90), but not in lichens. The correlations between Hg contents in mosses and the altitudes, latitudes and longitudes of sampling sites indicated the mountain trapping and spatial deposition of Hg in the Tibetan Plateau. 相似文献
968.
剩余活性污泥和厨余垃圾续批式混合中温消化试验研究 总被引:1,自引:0,他引:1
将加碱水解和未水解剩余活性污泥与厨余垃圾混合后进行序批式中温厌氧消化,对生化产甲烷势(BMP)进行了测定.剩余活性污泥的水解通过添加NaOH进行,合理的NaOH投量为40 mmol/L,在25 ℃和35 ℃下经过6 h的水解后SCOD水解率分别提高27.4%和31.1%.厨余垃圾、25℃和35℃下水解污泥的最终甲烷产量分别为607、284、312 mL/g(VS),两种水解污泥比未水解污泥分别高出43%、57.6%,水解污泥和厨余垃圾混合消化的可降解能力要优于未水解污泥和厨余垃圾的混合进料. 相似文献
969.
Monitoring the effectiveness of management activities within reserves is always a complicated task. When the focus of management
activities is mammals, it is difficult to monitor their populations in a way that is rapid, effective, and inexpensive. We
report on a mammal survey of a reserve in southwest China using remote-trip cameras. We surveyed 329 locations over 2 field
seasons in 2002 and 2003. Sixteen species of mammals were detected with these cameras, with four species documented for the
first time. After accounting for variation due to slope, aspect, elevation, and habitat type, the distribution of six species
was positively associated with the location of conservation stations and/or patrolling routes. Species of medium-sized mammals
are excellent candidates for monitoring programs based on these cameras, due to their relative abundance, sufficient size
to be detected by the camera units, and sensitivity to human activity. The distribution of mammals relative to management
efforts is a relatively rapid means to assess reserve effectiveness. The repeat use of the cameras as part of a monitoring
plan should provide a quantifiable measure of reserve effectiveness. 相似文献
970.