贵州百花湖消落区土壤磷赋存形态初步研究

Preliminary Study on Phosphorus Forms in Soils in the Water-level-fluctuating Zone of the Baihua Reservoir

应用磷形态标准测试程序(SMT)对百花湖(水库)消落区土壤磷赋存形态进行了分级测定,分析了各形态磷之间与样品理化性质如有机质、pH、总氮和含水率的相关性。结果表明,百花湖消落区1区全磷含量平均为1239.9mg/kg,2区为1097.4mg/kg,3区为1041.5mg/kg;各形态磷中有机磷占全磷的百分比1区为58.7%,2区为55.1%,3区降至54.7%;消落带土壤中的磷以有机磷为主,无机磷为辅。铁铝结合态磷则是无机磷的主要组分,其中1区为77.1%,2区为66.7%,3区为61.4%;全磷、有机磷和铁铝结合态磷含量的总体变化趋势为1区>2区>3区;而钙结合态磷含量却呈现出3区>2区>1区。有机磷与全磷显著性相关,是土壤中磷素增加的主要因素;无机磷与铁铝结合态磷和钙结合态磷显著性相关,二者的增加和减少对无机磷的含量具有显著影响;全磷与有机质、酸碱性显著相关;有机磷与有机质,钙结合态磷与酸碱性之间均呈现出显著性相关,表明土壤的有机质和酸碱性影响磷的含量和分布。

The contents of phosphorus of different forms in the soils in the water-level-fluctuating zone of the Baihua Reservoir were measured by using the standard measurement and test （SMT） procedure of phosphorus forms. Correlation coefficients were analyzed between phosphorus forms and samples＇ physical-chemical characteristics, including total nitrogen, organic mat- ter, pH and soil moisture content. The results showed that the total average phosphorus contents in the soils of zone 1 were 1239.9 mg/kg, 1097.4 mg/kg in the soils of zone 2 and 1041.5mg/kg in the soils of zone 3, respectively. The ratio of OP/TP in zone 1 （average value= 77.1%） was higher than that in the soils of zone 2 （average value= 66.7 %） ,and the ratio in the soils of zone 3 （average value = 61.4 %） was the lowest of them. The dominant phosphorus form in soils was OP · The average ratio of Fe/AI-P/IP in zone 1 was 78.9%, that was 64.2% in the soils of zone 2 , and it decreased to 54.6% in zone 1 . The domi- nant phosphorus form of IP was Fe/AI-P. The TP, OP and Fe/A1-P contents in the soils of zone 1 were highest,and those in the soils of zone 3 were lowest. The Ca-P average content in zone 1 was 108.6 mg/kg , higher than that in the soils of zone 2 （average content =84.3 mg/kg）. The content was 62.1 mg/kg in the soils of zone 1 . Positive correlations existed among the contents of TP ,TP and OP, between IP and Fe/A1-P, Ca-P, OM and pH , and between OP and OM, Ca-P and pH. All these results indicated that the increase of OP is mainly due to the increase of TP in the silos. The increase and decrease of the a- mounts of Fe/AI-P and Ca-P have an impact on the content of IP, and the contents of phosphorus are affected by OM and pH.