Insights into Distribution of Soil Available Heavy Metals in Karst Area and Its Influencing Factors in Guilin, Southwest China

The bioavailable contents of heavy metals in karstic soils are a subject increasing concern since the uptake by plants can pose severe threat to food safety and public health. However, their effective factors poorly understood karst regions. Calcareous soil red developed from carbonate clastic rocks, respectively, were chosen typical region (Guilin) southwestern China, total (CT) available (CA) 11 metals, as well influencing profiles, investigated. results showed that calcareous has greater organic carbon, nitrogen, potassium, calcium (Ca) than soil, but lower phosphorus C:N. Acid-soluble Ca (Aca) was dominant fraction both types soil. Heavy highly accumulated mainly controlled secondary enrichment processing rock weathering. For majority had higher CT CA According redundancy analysis (RDA) Pearson correlation coefficient, high pH content primary especially residual Aca CA. Additionally, cation exchange capacity clay minerals also probably improved immobility metals.