SUN Dali¹, WANG Hu², CHEN Miao¹, FU Tianling¹，HE Tengbing¹

(1.College of Resources and Environmental Engineering, Institute of New Rural Development, Engineering Laboratory of Pollution Control and Resource Reuse Technology of Guizhou Province in Mountainous Livestock and Poultry, Guizhou University, Guiyang 550025, China;
2. Guizhou Chuyang Ecological Environmental Protection Technology co., LTD, Guiyang 550025, China)

Abstract: In order to determine the soil geochemical baseline of the paddy field in the coal mining watershed of Guizhou Province. In this study, the rice fields in the Dumu River Coal Mining Basin in Longli County were used as the research area. A total of 47 farmland surface soil samples were collected and analyzed for 9 heavy metals( As, Cd, Cr, Cu, Pb, Ni, V, Li and Ti), a total of 47 rice samples were collected and analyzed for 6 heavy metals( As, Cd, Cr, Cu, Pb and Ni). The geochemical baseline values of the As、Cd、Cr、Cu、Pb and Ni were determined using the reference element method and the cumulative frequency curve method and discuss the applicability of geochemical baselines. The results show the following: The geometric mean values of As, Cd, Cr, Cu, Pb and Ni are 17.665, 0.489, 49.374, 23.842, 18.97 and 12.874 mg/kg, respectively; The geochemical baseline values determined by standardized methods are 17.656, 0.55, 49.043, 23.842, 19.08 and 12.88 mg/kg respectively; The geochemical baseline values determined by the relative cumulative frequency method were 12.034, 0.635, 48.355, 22.303, 17, and 12.12 mg/kg, respectively. Combining the baseline value of soil heavy metals and the limit value of heavy metal content of rice to carry out the regional cast point analysis. Based on the geochemical baseline value determined by the standardized method, the heavy metal elements with higher accuracy in the casting area are As, Cr, Cu, Pb and Ni. Based on the baseline value determined by the relative cumulative frequency line method, the heavy metal element with a higher accuracy rate in the casting area is Cd. Therefore, the baseline values of As, Cd, Cr, Cu, Pb and Ni determined by the standardized method can be used as reference values in this study area, and the baseline values of Cd determined by the relative cumulative frequency method as the reference values.

Key words:farmland; soil; heavy metal; Geochemical baseline; rice

EARTH AND ENVIRONMENT Vol.49, No.1, Tot No.344, 2021, Page 707-716