长期施肥条件下黑土镉的积累及其趋势分析

Cadmium accumulation and its development tendency in black soil under long-term fertilization

以中国科学院海伦农业生态实验站长期田间定位试验为基础,研究了长期定量施用氮磷化肥和猪粪对黑土Cd的积累及其有效性的影响,并对黑土Cd的积累趋势进行了预测.结果表明:在完全不施肥的自然农业生产条件下黑土Cd浓度略有增加;长期定量施用氮磷化肥使黑土Cd浓度显著增加,但不同化肥用量对黑土Cd积累的影响无显著差异;长期施用猪粪可显著增加黑土Cd的积累,且近年来有加速积累的趋势,含Cd饲料添加剂可能是猪粪中Cd的重要来源;施用氮磷化肥对黑土Cd的有效性无显著影响,长期施用猪粪则可显著提高黑土Cd的有效性.

Based on the long-term field experiment at Hailun Agro-ecosystem Experimental Station of Chinese Academy of Sciences, this paper studied the cadmium （Cd） accumulation, its development tendency, and Cd availability in black soil under effects of long-term application of chemical N and P fertilizers and pig manure. The results showed that under no fertilization, soil Cd concentration had a slight increase. Long-term chemical N and P fertilization increased soil Cd concentration significantly, but soil Cd accumulation had less difference under different N and P fertilization rates. Applying pig manure increased the Cd accumulation in soil significantly, and the accumulation had a tendency of speed-up. Cd-containing feedstuff additives could be the important source of Cd in pig manure. No significant effects of chemical N and P fertilization were observed on the Cd availability in soil, but long-term application of pig manure increased the Cd availability significantly.