香蕉茎叶堆制还田对土壤各形态钾的影响

在室内模拟大田环境中香蕉茎叶堆肥还田对土壤中各形态钾的影响。结果显示:土壤中添加香蕉茎叶腐熟材料能提高土壤的pH值,在0～240mg/kg(以香蕉茎叶中的钾折算每千克土中添加钾的量,下同)添加量下,土壤pH值随添加量的增加而升高,总体维持在6.3～7.0范围内;土壤速效钾的含量也随着堆肥样品添加量的增加而增大。由于堆肥样品中各种物质的影响,土壤速效钾的量高于外源钾添加量和原始土壤中速效钾的量总和,且速效钾增率随堆肥样品添加量的增加而增大。90d后土壤中速效钾增率仍维持在36.83%～137.58%之间。缓效钾的量与速效钾相比,堆肥样品添加量对其在土壤中的含量变化影响不大,在大部分时间内不同堆肥样品添加量下缓效钾的量差异不显著。

The Effects of Banana Stalk-leaf Compost on Different Forms of Soil Potassium

Simulating filed condition, the effects of banana stalk-leaf compost on different forms of soil potassium(K) were studied in a laboratory scale. The results indicated that the soil pH rose after the application of with mature compost of banana stalk-leaf. Specifically, under the K application of 0~240 mg/kg soil(calculated on the K content of banana stalk-leaf), pH would increase with the increase of compost application and was in the range of 6.3~7.0. The available K in the soil also increased with the increase of compost.application. The content of available K in the soil influenced by various factors was higher than the sum of aitive K from banana stalk-leaf compost and the available K in the original soil. The increase rate of available K rose with the increase of compost adding, which was still in the range of 36.83%~137.58% after 90 days. Comparing with the content of available K in the soil, compost adding affected little to the content of slow-release K and the no significant difference was observed by slow-release K under different compost adding in most of the time.