几种因素对红壤性水稻土锌的化学形态的影响

EFFECTS OF SOME FACTORS ON CHEMICAL FRACTIONS OF ZINC IN PADDY SOILS DERIVED FROM RED EARTH

用化学连续浸提法对本校设置的稻作制、有机肥和地下水位３因子多水平各处理红壤性水稻土中锌的化学形态进行分析测定，结果表明，由耕型第四纪红土红壤开垦而来的红壤性稻田土壤，锌以残留态锌为主，平均为７５．５２ｍｇ／ｋｇ，占土壤全锌含量的３６．５２％．其次是有机结合态和氧化铁结合态锌．其它形态所占比例较小．３种稻作制比较，冬泡能促使残留态锌和晶形氧化铁结合态锌向交换态、氧化锰结合态、有机结合态和无定形氧化铁结合态锌转化．高水位处理的土壤，交换态锌、有机结合态锌和晶形氧化铁结合态锌的含量大于低水位处理的土壤．不同有机肥施用量处理比较，土壤中交换态锌和无定形氧化铁结合态锌的含量是常量有机肥最高，高量有机肥次之，化肥最低．

The studies of soil Zinc fractionation revealed that most of the Zinc in red earth paddy soil derived from quarternary red clay was of residual forms,some were of organic complexed and iron oxide bounded forms,and a relatively small fraction was exchangeable and manganese bounded forms.Winter flooding could decrease residual and crystalline sesquioxide bounded forms of Zinc in soils,and increase exchangeable,organically complexed,manganese bounded and amorphous sesquioxide bounded forms of Zinc.Under two groundwater level conditions,the contents of exchangeable,organicolly complexed and crystalline sesquioxide bounded forms of Zinc in high groundwater level soils were higher than those in low groundwater level soils.Under three applying rates of organic manure conditions,the contents of exchangeable Zinc,amorphours sesquioxide bounded Zinc in heavily manured soils were higher than those in lightly manure and no manured soils.