Ecological restoration in contaminated soils of Kokdzhon phosphate mining area (Zhambyl region, Kazakhstan)
Abstract This study provides results of an ecological restoration activity performed in the Kokdzhon phosphate mining of the Zhambyl region (a semi-desert mining area of Kazakhstan). The test area was made by a quarry-hole, about 1.25 hectares wide, that was preliminarily filled with the earthy material of a dump and, subsequently, levelled. The total volume of human transported material (HTM) used was 700 tonnes. Soil samples were taken from 0 to 30 cm depth at 23 sampling sites and several soil quality parameters were determined. In the test area 750 tree species were planted in suitable dug holes: (150 seedlings of Russian Olive; 150 seedlings of Black Saxaul); 150 seedlings of Androsov …