Adaptability of Koenigia mollis to an Acid Tin Mine Wasteland in Lianghe County in Yunnan Province

Abstract

To explore the potential of Koenigia mollis as a pioneer plant in acid tin mine wasteland, Koenigia mollis plants and the corresponding rhizosphere soils in different areas in Lianghe County, Yunnan Province were collected, and their chemical properties and heavy metals contents were determined., the adaptability of the plant to the barren tailing environment and its acid resistance and tolerance to heavy metal such as Cu (Cu, CAS. No. 7144-37-8), Cd (Cd, CAS. No. 7440-43-9) and Pb (Pb, CAS. No. 10099-74-8) pollution were analyzed. Results showed that Koenigia mollis growth was normal. The pH value in rhizosphere soils was 3.74–4.30, which was strongly acidic. The organic matter (OM), total nitrogen (TN) (N, CAS. No. 7727-37-9), available potassium (AK) (K, CAS. No. 7440-09-7), and available phosphorus (AP) (P, CAS. No. 7723-14-0) contents in soils of the research area were in low levels. The total contents of Cu, Cd, and Pb in the soil of the research area exceeded the pollution risk screening value for the national risk control standard of soil environmental quality, indicating that Koenigia mollis has a certain resistance to acid and heavy metal pollution. In addition, Koenigia mollis has strong transport and enrichment capacity for Cu, Cd, and Pb and therefore has potential as a pioneer phytoremediation plant for acid tin mine wastelands and a remediated plant for agricultural land around metal mining areas.