摘要
对福建山地红壤磷吸附和解吸状况作了研究 ,结果表明 :福建山地红壤磷吸附与解吸状况极显著地吻合了Langmuir方程 ,运用该方程可推算出最大吸附量和标准需磷量。福建山地红壤磷吸附量较大、解吸量较小 ,且磷吸附量与土壤有机质、酸度、有效磷。
This paper studied the properties of P_adsorption and P_desorption in fujian mountain red soils for finding out the required quantities of the red soils for P and providing theoretical basis for fertilization in Southern mountain red soils. Five mountain red soils from eastern, northern, western northern and middle Fujian were used in this study. The top 0～20cm and 20～40cm of each soil profile were sampled, air dried, and sieved to pass a 2mm mesh. 50ml of KH2PO 4 solution (dissolved by 0.02 M KCL, pH7.0) were added to 5grams soil (quintuplicate) from each sample to give P rates at 100, 300, 500, 700 and 900 mg kg -1, intermittently shaken (28℃) for 24 h., centrifugalized and analyzed of P concentrations. P_adsorption amounts were calculated by differences between original and analyzed concentrations after adsorption. The treatments of P rates at 500, 900 mg kg -1 were used for P_desorption experiment, after adsorption and centrifugalization, liquid removed, 50 ml of 0.02 M KCI solution (no P) added to, intermittently shaken (28℃) for 24 h., centrifugalized and analyzed of P concentrations of centrifugalized liquid, P_desorption amounts cdlculated, continuous desorptions of three times. The results are as follows: the conditions of P_adsorption and desorption in fujian mountain red soils very markedly coincide Langmuir equation, it is possible to calculate max.adsorption and standard required P quantity by using the equation. The P_adsorption quantity is fairly large and the P_desorption rate very low in Fujian mountain red soils, and the relations are marked statistically between the P_adsorption quantity and the O.C., pH, available P, <0.001mm clay respectively. It needs further test and verify if the standard required P quantity 0.2mg/kg is applicable for mountain red soils in fujian.
出处
《山地学报》
CSCD
2001年第1期19-24,共6页
Mountain Research
