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本文对南广河水体中的砷镉铅铬含量分布特征进行了描述,并探讨了南广河的水质质量。结果表明:南广河从上游到了游水体中污染物含量为增大趋势;在时间上也存在一定的变化,枯水期水体中污染物含量高于水期和丰水期。目前南广河综合水质质量可满足Ⅱ类标准要求。 相似文献
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关于水磨河砷污染的分析 总被引:1,自引:0,他引:1
砷是世界上分布较广的元素,除砷矿及火山区外在自然界中含量都是较低的:地壳上层的岩石圈、土圈平均含量是5 mg/kg,地面水中的含量大都在0.005mg/L上下,在生物体乃至人体中都含有微量的砷我国黄河水中含砷量在0.002~0.16mg/L之间(应该注意黄河水中过高的砷,是由泥沙携带,溶解杰砷都在0.04mg/L以下),黄河流域如陕北一带的土壤中平均含量在10.38 相似文献
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西宁地区环境有害元素砷汞含量及其防治对策 总被引:3,自引:0,他引:3
对西宁地区自然环境(土壤、水体、农作物)中有害元素的调查分析表明,砷、汞含量水平相对较低,总体环境状况良好,局部土壤砷和汞的污染主要由人为活动(工业性大气降尘和农药、化肥施用等)所致。结合环境污染特点,探讨了砷、汞污染防治对策 相似文献
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成都地区典型土壤与农作物中砷含量研究 总被引:1,自引:0,他引:1
成都地区土壤和农作物中砷污染研究资料不多,本文以成都地区7类典型土壤和该土壤上生长的10余种常见农作物中的砷含量为研究对象,通过对监测数据的整理、分析,应用正态分布、方差分析、线性相关检验等方法对土壤和农作物中砷的分布规律以及两者的关系进行了比较详尽的分析和研究,并对比了国内相关研究结果,说明了成都地区土壤和农作物中砷污染的规律和相关性。 相似文献
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土壤-植物系统中磷和砷相互作用关系的研究进展 总被引:2,自引:0,他引:2
砷元素导致的环境污染问题日益突出,施磷已成为植物修复砷污染土壤过程中必要强化措施之一。土壤-植物系统中磷和砷的相互作用关系是非常复杂的,研究表明:磷和砷在土壤中往往是共生的,但又存在竞争吸附关系;磷和砷在不同植物中的相互作用关系主要有拮抗效应和协同效应;有必要通过分子生物学手段对磷和砷表达基理进行深入研究,获得对砷具有超积累能力的植株。 相似文献
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2019年,黄河流域生态保护和高质量发展成为国家战略,中央及黄河沿岸九省区都高度重视黄河流域的生态保护和生态治理,甘肃省也迈开了流域治理的坚实步伐.通过梳理黄河流域生态治理之理念及进展,分析了黄河流域甘肃段生态治理中的上游源头治理、流域体系化发展、左右岸统筹治理、流域复合型污染以及生态政策社会化等问题,提出了法治应对思... 相似文献
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Nitrogen contamination in the Yellow River basin of China 总被引:3,自引:0,他引:3
Nitrogen contamination is one of the most serious problems in the Yellow River of China. This study was conducted to analyze monitoring data on nitrogen contamination for the Yellow River basin in the years 1980, 1990, 1997, and 1999. Several significant results have arisen from the study. First, in conjunction with an increase in economic indexes from the Yellow River's upper basin to its lower basin, the nitrogen concentration in the tributaries also showed an increasing trend from the upper to the lower basin, which, in turn, led to an increase in the nitrogen concentration of the mainstream from the upper to the lower reaches. Second, nitrogen in the river water in the mainstream and the tributaries of the Yellow River was attributed mainly to point sources. In spite of the fact that the ratio of point to nonpoint sources decreased from 2.7 in 1990 to 1.8 in 1997 for total inorganic nitrogen in river water at the Tongguan Station in the lower basin, point sources increased more than nonpoint sources. Third, the ammonium nitrogen and total inorganic nitrogen content of the river water increased significantly in the mainstream and the tributaries during the 1980-1999 period, a change caused by an increase in wastewater discharge and nitrogenous fertilizer application in the Yellow River catchment. 相似文献
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Jiongxin X 《Environmental management》2004,33(5):637-653
The Yellow River has been intensively affected by human activities, particularly in the past 50 years, including soil–water conservation in the upper and middle drainage basin, flood protection in the lower reaches, and flow regulation and water diversion in the whole drainage basin. All these changes may impact sedimentation process of the lower Yellow River in different ways. Assessing these impacts comprehensively is important for more effective environmental management of the drainage basin. Based on the data of annual river flow, sediment load, and channel sedimentation in the lower Yellow River between 1950 and 1997, the purpose of this paper is to analyze the overall trend of channel sedimentation rate at a time scale of 50 years, and its formative cause. It was found in this study that erosion control measures and water diversion have counteractive impacts on sedimentation rate in the lower Yellow River. Although both annual river flow and sediment decreased, there was no change in channel sedimentation rate. A regression analysis indicated that the sedimentation in the lower Yellow River decreased with the sediment input to the lower Yellow River but increased with the river flow input. In the past 30–40 years, the basin-wide practice of erosion and sediment control measures resulted in a decline in sediment supply to the Yellow River; at the same time, the human development of water resources that required river flow regulation and water diversion caused great reduction in river flow. The former may reduce the sedimentation in the lower Yellow River, but the reduction of river flow increased the sedimentation. When their effects counterbalanced each other, the overall trend of channel sedimentation in the lower Yellow River remained unchanged. This fact may help us to better understand the positive and negative effects of human activities in the Yellow River basin and to pay more attention to the negative effect of the development of water resources. The results of this study demonstrate that, if the overuse of river water cannot be controlled, the reduction of channel sedimentation in the lower Yellow River cannot be realized through the practice of erosion and sediment control measures. 相似文献
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本文从资源环境超载、生态环境本底脆弱、水资源指标性短缺等方面对黄河流域煤化工产业发展的长期形势作出判断研究,系统梳理了煤化工产业发展的环境保护经验与教训,对煤化工产业发展中规模增长过快、布局不合理以及突出环保问题等经验和教训进行分析和评述。在此基础上,本文就黄河中上游煤化工产业高质量发展提出了若干建议,包括以生态环境安全格局稳定为原则,推动国家级煤化工相关专项规划编制及规划环评工作;转变传统发展模式,跨区域共建黄河中上游地区现代煤化工绿色技术创新平台;围绕再生水资源利用,推进煤化工“近零排放”和水权交易;按工业绿色发展理念和生态工业模式,促进煤化工产业优化升级等。 相似文献
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黄河流域环境污染与高质量发展已成为当前国内关注的重要问题,我国为应对黄河流域生态恶化带来的挑战制定了一系列环保政策。本文立足生态补偿政策并构建准自然实验,以 2005-2019年黄河流域 A股制造业上市公司为研究对象,运用多期双重差分法实证检验生态保护补偿政策对黄河流域制造业高质量发展的影响。研究发现:生态保护补偿政策的实施促进了黄河流域制造业高质量发展水平的提高且存在明显的区域异质性和产权异质性,具体表现在对黄河流域上游和国有企业制造业高质量发展促进作用明显高于中下游地区和非国有企业。社会责任承担和政府补助增加是生态保护补偿政策推进黄河流域制造业高质量发展的重要方式,上述研究结论在经过 PSM-DID、更换被解释变量、安慰剂检验后仍然具有稳健性。研究全面考虑了生态保护补偿政策在流域内不同区域发挥作用的渠道,有利于充分发挥生态保护补偿政策在黄河流域生态治理和高质量发展中的功效。 相似文献
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黄河流域是我国重要的生态功能区,是实现国家粮食安全的重点区域。本文梳理了近期黄河流域的相关研究,从粮食安全视角下分析了黄河流域现阶段在流域水效率、流域水管理机制、流域水生态文明三方面的问题,并提出了关于黄河流域大保护与高质量发展的两方面建议。一是创新流域水管理机制,服务国家粮食安全。积极改进水资源管理方式,加大节水宣传教育力度,加强黄河流域水土流失综合治理,合理调控水价,完善黄河流域水权市场建设。二是践行"两山"理论,提升流域水生态文明。建设"四大体系"和"七大区域",推进生态廊道建设;转变经济发展方式;提前布局水生态文明建设。 相似文献