Temporal and spatial variability and stability evaluation of soil arsenic pollution in Juzhang River basin

Abstract

To explore spatial and temporal variability of Arsenic (As) pollution and its stability of the soil in the Juzhang River basin, the data of 255 surface soil samples are analyzed in the study area. The analysis methods include Moran’s I, the semi-variant function, the inverse distance interpolation method and the superposition analysis. The results showed that: (1) in 2006 and 2016, the average content of arsenic in soil was 1.17–48.55 mg∙kg⁻¹ and 4.16–89.50 mg∙kg⁻¹, only a few samples exceeded the risk screening value (GB15618-2018), but not exceeded risk intervention value. (2) The soil As was positively correlated with the space in 2006 and 2016, and the distribution of As of soil was more obvious in 2016; the spatial continuity of As of soil is stronger in 2016 than that in 2006, and the space self-correlation range in 2016 was larger than in 2006. The spatial difference of As in different directions is different, and the distribution of As pollution in the soil has slight diffusion and weighting tendency, which is closely related to the distribution of the enterprises. (3) The soil stability in the southeast is lower, and the stability of the soil in the west is relatively high; the lower the soil stability is, the larger variations the pollution space have. However, the relationship between the degree of the soil As pollution and the stability of the soil is uncertain.