土壤有效钾与钾肥施用量关系的研究

在黄褐土和砂姜黑土上进行了 KCl施用量 (0、75、15 0、2 2 5、30 0 kg/ hm2 )与土壤速效钾增量和缓效钾增量关系的土培试验。结果表明 :KCl施用量与土壤速效钾增量及缓效钾增量之间均存在着极显著的线性正相关。KCl施用量产生的土壤速效钾增量 ,砂姜黑土 >黄褐土 ,水培 >旱培 ;在砂姜黑土上 ,旱培的缓效钾增量明显大于水培。经计算推测两种土壤的缓效钾 (K)“中等”指标值为 5 0 0 mg/ kg。本研究对测土施钾具有一定的指导作用

Study on Relationship between Available K in the Soil and the Application Amount of K Fertilizer

The relationship between KCl application amount (0,75,150,225,300 KClkg/hm 2)and the increasing amount of available and slowly available K researched in Shajiang black soil and yellow cinnamon soil was studied for soil culture. The results showed that the KCl application rate was extremely significantly and positively linear with the increasing amount of soil available and slowly available K. The increasing amount for soil available K by KCl application in Shajiang black soil was higher than that in yellow cinnamon soil, while the increasing amount under water culture was higher than that under dry land culture.The increasing amount of slowing available K under dry land culture was obviously higher than that under water culture in Shajing black soil. It was deduced by calculation that the medium index for soil slowly available K in two soils was 500 mg/kg.The results could be used for the direction for K application based.