贵州百花湖消落区土壤磷赋存形态初步研究

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。

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

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 matter, 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/Al-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 dominant phosphorus form of IP was Fe/Al-P.The TP, OP and Fe/Al-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/Al-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 amounts of Fe/Al-P and Ca-P have an impact on the content of IP, and the contents of phosphorus are affected by OM and pH.