Li, PJ (reprint author), Chinese Acad Sci, Inst Appl Ecol, Shenyang 110016, Peoples R China.
Fourteen soil properties in 17 sampling sites were analyzed to study the soil degradation in a magnesite mining area in Haicheng City, Northeast China. Such areas have hitherto received little attention. The current practices of magnesite mining in this area resulted in degradation of soil quality and specifically led to an increase in soil pH, the ratio of magnesium to calcium, bulk density, clay dispersibility, total magnesium and equivalent calcium carbonate and a decrease in surface soil porosity and available phosphorous. The soil quality in the areas affected by intensive mining activity was obviously worse than that of areas far away from the mine. Four factors were identified and "magnesium factor", "pH factor" and "fertility factor", involving 13 soil properties, explained 82% of the total variance in the entire data set. Discriminant analysis showed that the total magnesium, water-soluble calcium and available phosphorous were the most sensitive indicators for soil quality.