Monitoring Land Use and Land Cover Effects on Water Quality in Cheung Ek Lake using ASTER Images | Science Publications

American Journal of Environmental Sciences

Kensuke Kawamura¹  Endan Suwandana¹  Yuji Sakuno¹  Nara Im¹ 

关键词: Cambodia;    Remote Sensing;    Urbanization;    Water Environment;   

DOI  :  10.3844/ajessp.2015.1.12

学科分类：环境科学（综合）

来源: Science Publications

【 摘 要 】

Cheung Ek Lake is the biggest naturaltreatment plant for nearly 80% of wastewater and storm-water from Phnom Penhcity. Land Use and Land Cover (LULC) changes of the lake and its catchment areacould deteriorate capacity of the lake in purifying wastewater and affect toits water quality. The study aims to assess the relationship between LULCchanges and water quality using ASTER images with field observations. Threepairs of temporal ASTER images in 2002, 2009 and 2011 acquired in dry seasonwere used to make LULC map with five classes: (1) Urban or built-up areas, (2)rangeland, (3) agricultural land, (4) water bodies and (5) barren land, usingMaximum Likelihood (ML) classification method. Post-classification comparisonwas chosen to study changes from 2002 to 2009 and from 2009 to 2011. The waterquality data of the Ministry of Environment from 2000 to 2013 were used tostudy water quality change. Spatial distribution of water quality parametersincluding total phosphorus, total nitrogen, chemical oxygen demand, five-daybiochemical oxygen demand, total suspended solids and chlorophyll-a wasobserved in the rainy and dry seasons in 2012 and 2013, respectively. Theresults showed that ML gave moderate level with overall accuracy of around 60%and Kappa coefficient of around 0.48 for classification images in all threedates. Also, some significant change were happened between 2002 and 2011;rangeland decreased by approximately 22%, while agricultural land and urban orbuilt-up areas increased by more than 2 and 16%, respectively. In addition tothe downward trend of water quality status changes recorded by the Ministry ofEnvironment from 2000 to 2013, the spatial distribution maps revealed thatwastewater from the city was the main source of water quality deterioration.These results might be suggested that LULC changes of the lake’s catchment areaappeared to have negative effects on water quality of the lake.

【 授权许可】

Unknown