Cadmium Accumulation in Vegetable Plantation Land Soils under Protected Cultivation: A Case Study.

Cadmium (Cd) accumulation in vegetable plantation land soils under a greenhouse was investigated in Shouguang County, Shandong Province, China. A total of 128 soil samples were collected from different agricultural fields. Soil samples were digested with the mixture of hydrogen peroxide (H2O2) and nitric acid (HNO3), and Cd content in the digested solution was detected with inductively coupled plasma-mass spectrometry (ICP-MS). The results indicated that the concentration of Cd in the greenhouse vegetable field was significantly more than that in open vegetable field, cotton field, wheat/maize field, and uncultivated soils. Cadmium concentration increased with the cultivation age, and the related accumulation rate was 0.0289 mg Cd kg-1y-1 in a greenhouse vegetable field. Organic fertilizer such as livestock manure was the major source for Cd accumulation in the greenhouse vegetable field with the average input amount of 70.7 g Cd ha-1 y-1 from organic manure. Thus, a decrease of Cd input from organic fertilizer into greenhouse soils is necessary. [ABSTRACT FROM AUTHOR]