title: Space-time quantitative source apportionment of soil heavy metal concentration increments.
abstract: Assessing the space-time trends and detecting the sources of heavy metal accumulation in soils have important consequences in the prevention and treatment of soil heavy metal pollution. In this study, we collected soil samples in the eastern part of the Qingshan district, Wuhan city, Hubei Province, China, during the period 2010-2014. The Cd, Cu, Pb and Zn concentrations in soils exhibited a significant accumulation during 2010-2014. The spatiotemporal Kriging technique, based on a quantitative characterization of soil heavy metal concentration variations in terms of non-separable variogram models, was employed to estimate the spatiotemporal soil heavy metal distribution in the study region. Our findings showed that the Cd, Cu, and Zn concentrations have an obvious incremental tendency from the southwestern to the central part of the study region. However, the Pb concentrations exhibited an obvious tendency from the northern part to the central part of the region. Then, spatial overlay analysis was used to obtain absolute and relative concentration increments of adjacent 1- or 5-year periods during 2010-2014. The spatial distribution of soil heavy metal concentration increments showed that the larger increments occurred in the center of the study region. Lastly, the principal component analysis combined with the multiple linear regression method were employed to quantify the source apportionment of the soil heavy metal concentration increments in the region. Our results led to the conclusion that the sources of soil heavy metal concentration increments should be ascribed to industry, agriculture and traffic. In particular, 82.5% of soil heavy metal concentration increment during 2010-2014 was ascribed to industrial/agricultural activities sources. Using STK and SOA to obtain the spatial distribution of heavy metal concentration increments in soils. Using PCA-MLR to quantify the source apportionment of soil heavy metal concentration increments.
authors.affiliation: College of Resources & Environment, Huazhong Agriculture University, Wuhan, China; Key Laboratory of Arable Land Conservation (Middle & Lower Reaches of Yangtse River), Ministry of Agriculture, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Institute of Island & Coastal Ecosystems, Ocean College, Zhejiang University, Hangzhou, China; Department of Geography, San Diego State University, San Diego, CA, USA. Electronic address: gchristakos@zju.edu.cn.
authors.forename: George
authors.initials: G
authors.lastname: Christakos
authors.affiliation: Wuhan Geomatic Institute, Wuhan, China.
authors.forename: Mingwu
authors.initials: M
authors.lastname: Guo
authors.affiliation: Institute of Island & Coastal Ecosystems, Ocean College, Zhejiang University, Hangzhou, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Xiao
authors.affiliation: College of Resources & Environment, Huazhong Agriculture University, Wuhan, China; Key Laboratory of Arable Land Conservation (Middle & Lower Reaches of Yangtse River), Ministry of Agriculture, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
mesh_terms: D000383:Agriculture; D002681:China; D002947:Cities; D004784:Environmental Monitoring / Q000379:methods; D007221:Industry; D019216:Metals, Heavy / Q000032:analysis*; D008962:Models, Theoretical; D015999:Multivariate Analysis; D025341:Principal Component Analysis; D012044:Regression Analysis; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D062206:Spatial Analysis
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants
keywords: Accumulation; Principal component analysis-multiple linear regression (PCA-MLR); Quantitative source apportionment; Soil heavy metals; Spatiotemporal Kriging (STK)