Li S H, Hong L, Jin B X, Zhou J S, Peng S Y
Yunnan Provincial Geomatics Centre, Kunming, Yunnan, China.
College of Tourism & Geographic Sciences, Yunnan Normal University, Kunming, Yunnan, China.
J Environ Public Health. 2020 Apr 25;2020:4749765. doi: 10.1155/2020/4749765. eCollection 2020.
The increase of urbanization level has led to the rapid increase of impervious surface area (ISA). The aim of this work is to clarify the relationship between the ISA and water quality and lay a foundation for the improvement and protection of the water quality in the basin. Taking the Fuxian Lake Basin in Yunnan Province as an example, based on the Landsat ETM+ remote sensing image and the Gram-Schmidt (GS) image fusion algorithm, the four-terminal model and the linear spectral mixture model (LSMM) were used to extract the impervious surface of the watershed from 2006 to 2015. And statistical methods were used to distinguish its relationship with water quality. The results show that the four-terminal model and the linear spectral mixture model can effectively extract the impervious surface information of the Fuxian Lake Basin. The average root mean square error (RMS) of the image decomposition results from 2006 to 2015 was less than 0.02. In the past 10 years, the ISA has changed significantly in the Fuxian Lake Basin. The ISA showed an overall upward trend from 2006 to 2015. It increased from 24.73 km in 2006 to 35.14 km in 2015, an increase of 10.81 km. From the value anomaly, the ISA in 2006 and 2009 is lower than the multiyear average, and those in the other years are higher than the multiyear average. The percentage of ISA in the basin was significantly positively correlated with Chemical Oxygen Demand-Mn (CODMn) and total phosphorus (TP) ( is 0.772, 0.763), and the correlation in the flooding season was greater than that in the dry season. The ISA threshold for water quality deterioration is around 10% in the Fuxian Lake Basin. Reducing ISA coverage, controlling ISA to less than 10%, and preventing nonpoint source pollution during flooding season will be the best measures to effectively improve the water quality environment in the basin.
城市化水平的提高导致了不透水表面面积（ISA）的迅速增加。这项工作的目的是阐明ISA与水质之间的关系，为流域水质的改善和保护奠定基础。以云南省抚仙湖流域为例，基于Landsat ETM+遥感影像和Gram-Schmidt（GS）影像融合算法，利用四端模型和线性光谱混合模型（LSMM）提取了2006年至2015年流域的不透水表面。并采用统计方法区分其与水质的关系。结果表明，四端模型和线性光谱混合模型能够有效地提取抚仙湖流域的不透水表面信息。2006年至2015年图像分解结果的平均均方根误差（RMS）小于0.02。在过去10年里，抚仙湖流域的ISA发生了显著变化。2006年至2015年，ISA总体呈上升趋势。从2006年的24.73平方千米增加到2015年的35.14平方千米，增加了10.81平方千米。从值异常来看，2006年和2009年的ISA低于多年平均值，其他年份则高于多年平均值。流域内ISA的百分比与化学需氧量-锰（CODMn）和总磷（TP）显著正相关（分别为0.772、0.763），且汛期的相关性大于枯水期。抚仙湖流域水质恶化的ISA阈值约为10%。减少ISA覆盖面积，将ISA控制在10%以下，并在汛期防止面源污染，将是有效改善流域水质环境的最佳措施。
