The formation mechanism of the naturally green selenium-rich land characterized by high selenium and low heavy metal concentrations in the western Liyang Plain was investigated. An absolute principal component score-multiple linear regression（APCS-MLR） model was utilized to quantitatively assess the sources and contribution rates of major heavy metal elements （such as Se and Cd in surface soils，supplemented by geostatistical methods to analyze the spatial distribution patterns of elements from distinct sources. The results indicate that favorable environmental quality is exhibited throughout the study area. Activities involving fireworks and firecrackers，non-metallic building materials industries，and related transportation sectors contribute to elevated concentrations of elements such as As，Cd，Cr，Ni，Cu，Pb，and Zn in soil，however，the spatial extent and magnitude of the impact remain manageable. The exceptionally high selenium content and elevated Se/Cd ratio in the provenance area of the western sector are characterized as critical determinants enabling the development of this naturally high-selenium green soil in China. Secondary selenium enrichment in soils is significantly augmented by long-term rice cultivation，representing a core supplementary mechanism sustaining the universally high Se/Cd ratio observed across the region.