土壤胡敏酸与铜、锌离子的络合特征及生物有效性的研究

通过田间试验研究了胡敏酸(HA)与铜、锌离子的络合特性。结果表明,施肥后土壤HA向结构复杂方向转化,HA与Cu2+、Zn2+之间的络合稳定性提高。HA-Cu2+的logk值,有机肥大于化肥;HA-Zn2+的logk值,以化肥的作用更明显。土壤HA与Cu2+或Zn2+络合,倾向于形成混合或多核络合物。施有机肥可提高HA-Cu2+或HA-Zn2+的结合强度和增加结合数量,而施化肥处理则相反。培养试验结果表明,有机肥处理的HA,玉米吸收Cu2+、Zn2+量下降,单施化肥处理下降较小;其中Cu2+吸收量受影响程度较大,而Zn2+吸收量没有那么明显。

Complexing characteristics of HA with copper and zinc and their biological availability

In this paper,we studied the characteristics of complexes between Cu~(2 ) /Zn~(2 )and HA and their availability under field condition.The results showed that long-term fertilization resulted in a construction of soil HA more complicated,and the complexes stability of HA-Cu~(2 )/Zn~(2 ) more stable.Applying organic fertilizer could enhance logk value of HA-Cu~(2 ) compared to chemical fertilizer; but the result was inversed for HA-Zn~(2 ) in which applying chemical fertilizer had a more significant positive effect on logk.Soil HA was inclined to form mixed or mixed or polynuclear complexes with Cu~(2 )/Zn~(2 ).Applying organic fertilizer could increase the complexing strength and capacity of HA with Cu~(2 ) /Zn~(2 ).However,applying chemical fertilizer could promote the activity and availability of HA-cation resulting in a reversed picture.The incubation experiment showed that applying HA treated with organic fertilizer reduced more Cu~(2 )/ Zn~(2 ) uptake than single application of chemical fertilizer in maize.In general,different fertilization had a more pronounced effect on Cu~(2 ) than Zn~(2 )more pronounced.