Welcome to visit Geoscience!

Geoscience ›› 2018, Vol. 32 ›› Issue (06): 1302-1310.DOI: 10.19657/j.geoscience.1000-8527.2018.06.18

• Geochemistry • Previous Articles     Next Articles

Study on Concentration Characteristics and Influencing Factors of Heavy Metals in Soils in Longhai, Fujian Province

SUN Kai1,2,3(), SUN Binbin1,2(), ZHOU Guohua1, HE Ling1,2, ZENG Daoming1,2, WU Chao1,2, CHENG Xiaomeng1,2   

  1. 1. Key Laboratory of Geochemical Exploration,Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences, Langfang,Hebei 065000,China
    2. International Center on Global-scale Geochemistry,United Nations Educational Scientific and Cultural Organization,Langfang,Hebei 065000,China
    3. China University of Geosciences,Beijing 100083,China
  • Received:2018-01-17 Revised:2018-06-05 Online:2018-12-10 Published:2018-12-20

Abstract:

To prevent ecological risk from heavy metals in soils in Longhai County, heavy metal concentration and their speciation characteristics as well as influencing factors of heavy metals were studied by classic statistical methods and random forest. The results show:(1) most heavy metals are enriched in paddy soils derived from Quaternary alluvial, deluvial or marine sediments;(2) the available contents of heavy metals in red soils in hilly and mountainous areas are relatively higher, which are derived from acid rock in Yanshanian age;(3) the speciation contents of As,Cu and Ni are correlated with their total contents, but the correlation is poor for Cd, Cr and Hg;(4) except for the total amount of elements, the effects of soil physico-chemical properties on the speciation of heavy metals are varied significantly. It presents that soil organic matter have great impact on the fraction contents of heavy metals of weak-bound to organic matter(except for Ni, Pb) as well as ion exchangable and carbonate-bound fractions of Cd and Zn. The cation exchange capacity has effect on all forms of Ni. The ratios of (Fe×Al)/Si have effect on the fractions of Cu. However, soil origin and soil type seems to have little effect on heavy metal fractions. The study shows that the labile fraction of heavy metals is not corresponding to their total contents in most cases. Therefore, it is necessary to consider the speciation characteristics of heavy metals in soil when assessing their ecological risk.

Key words: heavy metal in soil, soil origin, influencing factor, random forest, Longhai County, Fujian Province

CLC Number: