无径流和淋溶条件下钾肥利用率的研究

应用盆栽模拟试验方法，在无钾的径流和淋溶损失情况下，连续3年种植玉米，测定出广西10种土壤的钾肥利用率为79．0％～93．8％，平均为87．5％，研究结果表明，钾肥利用率与作物收获后的土壤速效钾含量呈极显著的负相关，与土壤阳离子交换量(CEC)也呈显著的负相关，土壤供钾量的估算方法对钾肥利用率的计算结果影响较大，土壤供钾量应依据种植前和收获后土壤供钾水平的改变及土壤对钾的缓冲能力来估算才符合实际情况，钾肥利用率的计算也应以此为基础。

Study on the recovery rate of K fertilizer under no runoff and no leaching conditions

Under pot culture conditions with no runoff and no leaching, the recovery rate of K fertilizer of the 10 major soil types of Guangxi were investigated and the values ranged from 79.0% to 93.8%, with an average of 87.5%. The correlation of the recovery rate of K fertilizer to soil available K after harvest was negative and very significant, and so was to soil cation exchange capacity (CEC). The calculation ways of the supply of soil K influenced the recovery rate of K fertilizer very greatly. The calculation of supply of soil K should be based on the variations of soil K status between planting and after harvesting and the buffer property of soil K, and so as the recovery rate of K fertilizer.