攀西地区新垦土壤对磷的固定和释放作用的研究

对攀西地区新垦土壤磷固定释放行为的研究表明,新垦土壤全磷、有效磷含量低,经水浸泡后土壤有效磷含量提高。根据对磷的固定特征,把供试土壤分为两类,红壤、重壤质性改土与目标土壤(菜园土、水稻土)相似,为第一类土壤,其固磷率高、释磷率低;而漂灰土、荒地土、旱坡土、砂质新改土为第二类土壤,其固磷率低、释磷率高。供试土壤固磷曲线与三种吸附模型拟合。Freundlich和Temkin方程的拟合度呈极显著水平,以Fleundlich方程最优,Langmuir方程只有部分吻合。

Study on Phosphor Fixation and Release of Newly Reclaimed Soils in West Area of Panzhihua

The results obtained by studying soil-P fixation and release in west reclaimed area of Panzhihua showed that total P and available P were low in all newly reclaimed soils and that available P increased after they were soaked in water for 4 days. According to soil P fixation characteristic, the studied soils were divided into two kinds. Red soil and newly cultivated heavy loam, the first kind, were resemble to target soils (vegetable growing soil and paddy soil), they had high P-fixation, low P-release rate; whereas bleached soil, waste land soil, sloping dry-land soil and newly cultivated sandy soil were the second kind, had low P-fixation, high P-release rate. In the three absorption models, Freundlich and Temkin equation were significantly correlated to P fixation data, and the Freundlich equation was the more , but the Lang muir equation only fit some data.