Abstract:At present, the study about historical mining wasteland as the object, the spatial distribution characteristics of reclamation soil quality and the relationship between the spatial distribution characteristics of soil quality and the response to reclamation measures are rarely reported in the literature. Based on classical statistics, variation function theory and empirical Bayesian Kriging method, the southwest area of historical sulfur mining wasteland reclamation area as the research object, from two aspects of point and area, the spatial distribution characteristics of reclamation soil heavy metals were systematically analyzed, and the quantitative relationship between them and reclamation measures was revealed. The results showed that the combined method of classical statistics, geostatistics and empirical Bayesian Kriging was feasible to reveal the spatial distribution characteristics of soil heavy metals. The variation coefficients of heavy metals in the five soils were larger, which were consistent with the characteristics disorder, the variability and the spatial uniformity and the abrupt change of land reclamation. The enrichment coefficient of heavy metals in soil was more than 2. Under the interaction of mining, reclamation measures and topography interaction, the heavy metals in different soils had a certain similarity in the global space, in the northsouth and eastwest basically showed two low and high in the middle of the inverted “U” trend. The C0/(C0+C1) of most heavy metals of reclaimed soils was 50%, and the random factors, such as soil cover, soil fertility and soil pH value regulation, were dominant in the spatial variation of different heavy metals. No matter what kind of heavy metals, the eastern of the first region, the northern of the second region, and the western of the fourth region had higher heavy metal content;the western of the first and second regions, the northern of the third region was relatively low. The average content of heavy metals in forest land and grassland was higher than that of cultivated land, and the heavy metal pollution, especially the Cd, was needed to control the heavy metal pollution in the future. With the increase of the effective soil layer thickness, the heavy metals in the soil showed a decreasing trend. There was no significant difference of soil heavy metal between the effective soil layer thickness in 30~100cm, which suggested that the effective soil layer thickness of the reclaimed soil in the study area was 100cm or more. As soil pH value became smaller, the total heavy metals in reclaimed soil showed an increasing trend, but the control of pH value to reduce the content of heavy metals in soil needed to be maintained at a certain extent, the pH value of proposed study area was continuously controlled in 7 ~ 8. The research results would provide guidance on the method of quality monitoring for the reclamation of abandoned industrial and mining land, and provide a scientific basis for historical mining wasteland reclamation soil heavy metal pollution further control and management.
