改性膨润土对东北石灰性土壤磷肥效果影响的研究

Enhanced Efficacy of Phosphate Fertilizer Mixed with Modified-Montmorillonite Applied in Calcareous Soil in the Northeast China

在东北石灰性土壤上采用田间试验方法,研究了改性膨润土对东北石灰性土壤磷肥效果的影响。结果显示,玉米不同生育期植株吸磷量和磷肥利用率显著增加。改性膨润土使玉米能够平稳而持久地吸收磷素营养,对提高磷肥利用率有重要意义。

Naturally occurring high-molecular polymer-compounds plus carbonate (particle size<0.16 mm pH=6.0) were mixed with montmorillonite clay (1∶8, V/V) and heated for 24 hours, forming a modified-montmorillonite. The modified-montmorillonite was then mixed with several chemical fertilizers includingurea, ammonium sulphate, ammonium phosphate, potassium chloride, and so on in processing practically available particle-fertilizers with a ratio of N∶P2O5∶K2O of 17∶14∶9, respectively. This mixed fertilizer was applied on corn field plots characterized by calcareous soil in the Northeast Region in China with 4 treatments with three replicates for each treatment to test the utilization ratio of phosphorus in the fertilizer. To analyze phosphate contents in soil, crop tissues, a conventional method was employed. It has been found that the fertilizer exhibited a remarkable enhancement for uptake of phosphorus by corn in comparison with the control plots. It may be concluded that the utilization of the modified-montmorillonite clay in the mixed fertilizer are really beneficial toeither corn production or protection of environment.