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Assessing Impact of Urbanization on River Water Quality In The Pearl River Delta Economic Zone, China 总被引:4,自引:0,他引:4
The Pearl River Delta Economic Zone is one of the most developed regions in China. It has been undergoing a rapid urbanization since the reformation and opening of China in 1978. This process plays a significant impact on the urban environment, particularly river water quality. The main goal of this present study is to assess the impact of urban activities especially urbanization on river water quality for the study area. Some Landsat TM images from 2000 were used to map the areas for different pollution levels of urban river sections for the study area. In addition, an improved equalized synthetic pollution index method was utilized to assess the field analytical results. The results indicate that there is a positive correlation between the rapidity of urbanization and the pollution levels of urban river water. Compared to the rural river water, urban river water was polluted more seriously. During the urban development process, urbanization and urban activities had a significant negative impact on the river water quality. 相似文献
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Wang M Markert B Chen W Peng C Ouyang Z 《Environmental monitoring and assessment》2012,184(10):5889-5897
In order to evaluate the current state of the environmental quality of soils in Beijing, we investigated contents of 14 metals in Beijing urban soils inside the 5th ring road by even grids sampling. Statistic analyses were conducted to identify possible heavy metal pollutants, as well as the effects of land uses on their accumulation. Our results revealed that the urban soils in Beijing were contaminated by Cd, Pb, Cu, and Zn. Land uses and urbanization ages affected the accumulation of the four heavy metals in soils significantly. Soils in industrial areas have the highest average Cu and Zn contents, while Pb contents in park areas and Cd in agricultural areas are the highest. The accumulations of Pb and Zn in urban soils increase significantly with sampling plots approaching the city center. And Pb, Cd, and Zn contents in soils in traffic areas also tend to increase in the city center. However, residential areas have the lowest contents of all the four heavy metals. 相似文献
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为了研究曝气池空间内水质的分布及变化规律,采用了YSI6600 V2多参数水质检测仪对成都市三瓦窑污水处理厂的一期工程传统污泥法(CAS)、二期工程缺氧、好氧和内源呼吸(AOE)工艺中的曝气池分别进行了包括DO、NH3-N、NO3--N、pH、氯化物和温度等水质指标的场的检测,通过分析这些数据,揭示了曝气池内部水质变化的规律,并比较了CAS工艺与AOE工艺内水质处理效果的差别。结果表明,(1)溶解氧沿池深方向呈现出一定的分布规律,CAS工艺中随池深增加,溶解氧增加,AOE工艺中随着池深的增加,溶解氧降低;(2)AOE工艺对氨氮在O区的去除率可达97.64%,明显高于CAS工艺的41.76%;(3)沿曝气池长度测量溶解氧空间分布规律,参照理论曲线及依据水质处理要求,调整曝气量的方法具有长期运行经济、水质处理效果好的特点。 相似文献
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采用土壤柱试验研究了土壤渗滤对再生水中有机微污染物的去除性能。结果表明,土壤柱对再生水中的DOC、UV254、总氮和总磷有较好的去除效果,并具有较高的抗冲击负荷的能力;土壤表层10 cm厚度对DOC的去除起主要作用;UV254和AOX在土壤表层10 cm厚度降解效果不明显,随着深度增加去除率逐渐升高;液相色谱有机碳探测(LC-OCD)检测结果表明,土壤柱对溶解性有机物质的去除主要体现在对多糖物质的降解上,其次是有机酸类,对腐殖质也有一定的去除作用。 相似文献
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Yun Ouyang Elizabeth A. Wentz Benjamin L. Ruddell Sharon L. Harlan 《Journal of the American Water Resources Association》2014,50(2):448-467
Studies that evaluate determinants of residential water demand typically use data from a single spatial scale. Although household‐scale data are preferred, especially when econometric models are used, researchers may be limited to aggregate data. There is little, if any, empirical analysis to assess whether spatial scale may lead to ecological fallacy problems in residential water use research. Using linear mixed‐effects models, we compare the results for the relationship of single‐family water use with its determinants using data from the household and census tract scales in the city of Phoenix. Model results between the household and census tract scale are similar suggesting the ecological fallacy may not be significant. Common significant determinants on these two spatial scales include household size, household income, house age, pool size, irrigable lot size, precipitation, and temperature. We also use city/town scale data from the Phoenix metropolitan area to parameterize the linear mixed‐effects model. The difference in the parameter estimates of those common variables compared to the first two scales indicates there is spatial heterogeneity in the relationship between single‐family water use and its determinants among cities and towns. The negative relationship between single‐family house density and residential water use suggests that residential water consumption could be reduced through coordination of land use planning and water demand management. 相似文献
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扬州经济开发区通过国家生态工业示范园区的创建和国家循环经济试点工作,构建以工业共生、物质循环、自然和谐、宜业宜居为特征及资源节约型、环境友好型开发区。本文介绍了扬州经济开发区发展循环经济的实践情况,以“减量化、再利用、资源化”和“可持续性”原则为理念,分析了其循环经济发展存在的问题,并提出了相应对策和规划。 相似文献
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多频管中电流法通过计算管道防腐层绝缘电阻来判断管道外防腐层的状态,近年来得到较为广泛的应用.但对于丘陵山地的埋地输油气气管道,其评价结果与实际状态有一定差距.通过研究发现,评价结果与实际状态不符的主要原因是:管道分布电容、管道分布电感在GDWFF处理软件中对防腐层评价结果影响较大,尤其是管道分布电感是关键参数.为此,修正了多频管中电流法评价软件给出的管道分布电感推荐值,并采用现场开挖的方式进行验证,说明评价结果更符合山地实际. 相似文献