旱改水对土壤铜含量及其有效性的影响研

旱改水对土壤Cu含量及其有效性的影响研究结果表明 ,代换态铜是土壤中Cu的强度因子 ,而晶形铁结合态铜和残留态铜为植物无效态铜且需经形态转化才有效 ,其他形态铜既是容量因子也是强度因子 ,其有效程度大致为无定形铁结合态铜 >有机结合态铜 >氧化锰结合态铜 >碳酸盐结合态铜。旱改水促进碳酸盐结合态铜、氧化锰结合态铜尤其是残留态铜向代换态铜、无定形铁结合态铜和有机态铜转化 ,提高土壤铜有效性和可移动性 ,并使Cu淋溶损失 ,导致水旱轮作土壤耕层全Cu贫化

Efects of cropping system of the rotation of upland crop and rice on the total and available copper contents in soils

The study on the effects of cropping system transformation from upland farming to the rotation of upland crop and rice on the total and available copper contents in calcic concretion black soils shows that the Ex Cu is the intensity factor of the available copper; the OM Cu, AFeO Cu, MnO Cu and Carb Cu are the capacity factor of the available copper; the Res Cu and CFeO Cu are unavailable for plants but can be activated under the artificial cultivation. The ratios of Res Cu, CFeO Cu, Carb Cu and MnO Cu to the total copper during the rotation of upland crop and rice decrease and on the contrary, those of OM Cu, Ex Cu and AFeO Cu increase, which enable the copper to be more movable and available, and finally lead to the reduction of total copper contents in tilling layer due to leaching.