北方河流生态护岸技术初探

生态水利是水利事业发展的大方向,干旱、少雨、河道生态环境恶劣、水土流失现象严重是北方河流的显著特点,探讨适合北方河流生态建设的护岸型式对于缓解和改善河道生态有一定的积极作用。     

Property rights and groundwater in Nebraska

Property rights are important institutions that influence economic performance and reflect the historical, cultural, and political realities of particular societies. Drawing on a variety of concepts from legal and economic studies, a framework for explaining the origin and evolution of property rights is developed and applied to the specific case of changing ground water rights in Nebraska. The Nebraska case is an interesting example of reliance on local control in regulating water use. Despite the importance of local initiatives in ground water management, this case also illustrates the need for external support from the judicial and legislative systems. The evolution of ground water property rights in Nebraska, as in other parts of the United States, has been conditioned by historical circumstances and changing values and attitudes as well as by economic and political forces.     

污染河流生态修复研究

[目的]寻求一种适宜城市污染河流的修复方法.[方法]选择苏南某市具有代表性的河流的老城段为研究对象,采用人工湿地、浮岛式湿地和净化浮岛3种河流修复方式对污染河流进行净化修复.[结果]浮水植物(圆币草和聚草)相较于挺水植物(黄花鸢尾、花叶芦竹、芦苇、水培冬青、千屈菜)修复效果好,去除率分别为:总氮37.9％和34.1％,总磷80.1％和73.5％,COD81.1％和74.8％,氨氮80.6％和85.9％,SS59.1％和77.3％;净化浮岛、人工湿地、浮岛式湿地3种修复技术中净化浮岛的去除效果相对较好,去除率分别为;总氮87.6％,总磷71.3％,氨氮87.6％,COD 97.5％,SS 81.8％;工程段底泥和水样的硝化速率和反硝化速率明显高于参照段,分别高出15.4％和21.1％;工程段和非工程段底泥的硝化速率和反硝化速率明显高于水样,分别高出26.9％和31.8％;曝气条件下修复植物对总磷、总氮、COD以及SS去除效果好于未曝气条件.[结论]净化浮岛工程对城市污染河流具有显著的修复效果.     

天津地区主要河流中磷含量分布调查研究

[目的]考察天津地区主要河流富营养化的程度,了解造成水体富营养化的主要影响因素。[方法]调查研究天津主要河流中的磷含量分布,采用钼锑抗分光光度法测定水体中的磷含量。[结果]海河的磷含量远高于津河和御河。海河的平均磷含量为0.220mg/L,津河为0.082 mg/L,御河为0.110 mg/L。而当磷含量达到0.100 mg/L时,即属于富营养化水体。[结论]天津地区3条主要河流海河、津河、御河中磷含量基本都达到了水体发生富营养化的浓度,3条河流已经受到不同程度的污染。     

管道定向钻穿越河流的工程地质勘察问题

对管道定向钻穿越河流的工程地质勘察工作中出现的一些问题进行了总结和探讨，认为勘察钻孔工作量和布置应随场地条件而异，科学合理地安排，而不宜教条地执行规范、规程中的某些条款。在勘探手段的应用上，提出采用工程物探与地质钻探相结合的综合勘探方法。     

Water-Quality Trends in the Nation's Rivers

Water-quality records from two nationwide sampling networks now permit nationally consistent analysis of long-term water-quality trends at more than 300 locations on major U.S. rivers. Observed trends in 24 measures of water quality for the period from 1974 to 1981 provide new insight into changes in stream quality that occurred during a time of major changes in both terrestrial and atmospheric influences on surface waters. Particularly noteworthy are widespread decreases in fecal bacteria and lead concentrations and widespread increases in nitrate, chloride, arsenic, and cadmium concentrations. Recorded increases in municipal waste treatment, use of salt on highways, and nitrogen fertilizer application, along with decreases in leaded gasoline consumption and regionally variable trends in coal production and combustion during the period appear to be reflected in water-quality changes.     

中小型河流突发氨氮污染应急处理技术研究

针对中小型河流突发性水体污染,以突发氨氮污染为例,探究水体污染应急处理技术.结果表明,氨氮浓度为10 mg/L左右时,平均自然降解系数KN为0.009 d-1;同一工况下,不同工艺对水中氨氮的去除能力表现为活性炭吸附＞自然曝气+沸石＞自然曝气.但在实际工程操作过程中,综合考虑工程的经济及可行性,在处理突发性氨氮污染时,建议主要采用自然曝气+沸石法去除氨氮,活性炭作为辅助吸附剂,从而提高氨氮的整体去除效果.     

城市河流生态环境修复探讨

在研究国内外现有的对城市河流生态景观研究的基础上,通过对南淝河生态环境的修复,将南淝河的生物、植物群落一起融入城市公共空间,形成人与水相和谐的生态环境,成为合肥市的生态景观廊道。     

河流中溶解态污染物水质模型

通过对河流中溶解态污染物的迁移运行规律的讨论，建立了河流污染带二维水质模型，经原体观测检验，模型计算值与观测值相当吻合。     

南方城市受污染河道的生态修复技术研究现状与展望

河道作为城市生态系统的重要组成部分,其污染问题受到了普遍关注.近年来,全国掀起了城市河道治理的热潮,一些城市的点源污染已得到控制,黑臭现象基本消除,城市河道面貌初步改观.在点源污染得到控制的基础上,面源污染的控制和生态系统的恢复逐渐成为河流研究的热点和治理城市河道的大趋势.综述了目前国内外主要应用的河道生态修复技术,提出必须结合多种河道修复技术,并且从流域尺度进行河道的生态系统恢复.