| To obtain water and fertilizer management for safety crop production in cadmium contaminated soil, the effects of different water and fertilizer treatments on crop growth, cadmium uptake and microbial characteristics in cadmium contaminated soil were investigated using pot experiments. The main findings are outlined as follows:(1) At 60 days after tranplanting, fertilization (N 0.25 g·kg-1, P2O50.1 g·kg-1, K2O 0.1 g·kg-1) and alternate irrigation (75% of full irrigation amount) treatment had the best growth of maize and lowest Cd uptake under high Cd condition (2 mg·kg-1).(2) At the cabbage harvest, under the low-cadmium (1 mg·kg-1) condition, irrigation (full irrigation amount) and high-nitrogen (0.3 g·kg-1) treatment had the highest cabbage yield, low cabbage Cd uptake, can increase soil respiration. under the high-cadmium (3 mg·kg-1) condition, alternate irrigation (70%) and nitrogen (0.15 g·kg-1) treatment had the highest cabbage yield, low cadmium uptake, higher activities of urease and neutral phosphatase and microbial biomass C in soil.(3) In cadmium (2 mg·kg-1) contaminated soil, fertilization (N 0.105 g·kg-1, P2O5 0.07 g·kg-1, K2O 0.105 g·kg-1 and bio-fertilizer 0.98 g·kg-1) and alternate irrigation (70%) treatment had higher cabbage yield, lower total cadmium uptake and higher activities of sucrose and urease.(4) In comparison, in cadmium contaminated soil, fertilization (N 0.35 g·kg-1, P2O5 0.1 g·kg-1, K2O 0.15 g·kg-1) and alternate irrigation (70% of full irrigation amount) treatment had the highest cabbage yield, lower cadmium uptake, larger soil invertase activity and stronger soil respiration.In summary, fertilization (N 0.35 g·kg-1, P2O5 0.1 g·kg-1, K2O 0.15 g·kg-1) and alternate irrigation (70%) treatment had the highest cabbage yield, lower cadmium content, and slight improvement of microbial properties, suggesting that our results can provide scientific basis in water and fertilizer management for safety crop production in cadmium contaminated soil. |
