水稻土中铁还原与无机磷有效性的关系

采集我国吉林省吉林市(1号)、四川省邛崃市(2号)、江西省安福县(3号)及广东省雷州半岛(4号)等地区的四种典型水稻土,通过模拟厌氧培养试验,研究在厌氧还原条件下不同水稻土中Fe(II)产生量、有效性磷浓度及A l-P、Fe-P和O-P等无机磷形态变化情况。结果表明,淹水后四种水稻土中Fe(II)含量均有不同程度的增加,土壤有效磷浓度也呈现相同的变化趋势。淹水60天后在1、2、3、4号土壤中,Fe(II)的净增加量分别为5.5mg g-1,4.3mg g-1,2.1mg g-1和3.7mg g-1;有效磷的增加量分别为50 mg kg-1,18.6 mg kg-1,23 mg kg-1和12.4 mg kg-1。厌氧培养30天内土壤Fe(II)产生量与有效磷浓度的变化呈极显著的相关关系。在1、2、3、4号土壤中,Fe(II)与有效磷的相关系数依次为0.9679、0.9744、0.8949和0.7501。

The Relationship Between Iron Oxides Reduction and Inorganic Phosphorus Availability in Four Paddy Soils of China

Four kinds of paddy soil from Jilin(No.1),Sichuan(No.2),Jiangxi(No.3) and Guangdong(No.4) of China were collected,and the changes of Fe(II),Al-P,Fe-P,O-P and available phosphorus under an anaerobic condition in these four paddy soils were determined.The results showed that the concentration of Fe(II) increased under the anaerobic condition,and the same trend was observed in available P.After flooded for 60d,the increase of Fe(II) was 5.5mg kg-1,4.3mg kg-1,2.1mg kg-1 and 3.7mg kg-1,and the increase of available P was 50 mg kg-1,18.6 mg-1kg,23 mg kg-1 and 12.4 mg-1kg for sample 1,2,3 and 4,respectively.The close relationship between the concentration of Fe(II) and soil available phosphorus were obtained in all these 4 paddy soils,and the concentration of soil available phosphorus increased significantly with the increasing of Fe(II) during the anoxic incubating process.The correlation coefficients of Fe(II) and available phosphorus were 0.9679,0.9744,0.8949 and 0.7501 for sample 1,2,3 and 4,respectively.