Abstract: To clarify the distribution characteristics and sources of heavy metals in soil weathered from the Cambrian Qingxudong formation in karst area, overlying soil samples, including surface soils and profile soils, were collected from Qingxudong formation in Kaiyang, Songtao, Bijiang, Zhenyuan, Taijiang, Kaili, and Duyun. The concentrations of heavy metals and trace elements in the soils were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the concentrations of Cd, Cr, Cu, Ni, Pb and Zn in surface soils were 3.46, 77.98, 34.83, 48.66, 90.18, 562.78 mg·kg^-1, respectively. Heavy metals in the surface soil showed obvious accumulation characteristics, with cumulative degree of Cd>Pb>Zn>Ni>Cu>Cr. Heavy metals in soil profiles were characterized by significant accumulation of Cd, Pb and Zn at the bottom. The main accumulative elements Cd, Pb and Zn were closely related to the leadzinc mineralization of Qingxudong formation.

Key words: energy balance., tilt correction, triple rotation, double rotation, eddy covariance, planar fit