【摘要】：土壤非交換性鉀的釋放總量和釋放速率是土壤供鉀能力的重要指標.本文采用CaCl2連續(xù)提取的方法研究了22年長期不施肥(CK)、NP(不施鉀肥)、NPK(施鉀肥)、NPKS(鉀肥與秸稈還田配施)和S(單施秸稈)對紫色土非交換性鉀釋放特性的影響,以期為紫色土鉀素管理提供科學依據(jù).結(jié)果表明:當運用不一樣的施肥處理紫色土非交換性鉀的釋放全部是前期迅速釋放、后期緩慢平穩(wěn)釋放的特點.采用4種動力學方程對紫色土交換性鉀的釋放過程進行模擬發(fā)現(xiàn),前期快釋放階段(1~168h)用Elovich方程(對數(shù)曲線方程)模擬最佳,釋放量占全過程的74.2%~77.0%;后期慢釋放階段(168~1 472h)用拋物線方程模擬效果最佳.不同處理土壤非交換性鉀的釋放速率和釋放量的差異有統(tǒng)計學意義,其大小為:S原始土壤NPKS、CKNPKNP,長期不施鉀肥的NP處理非交換性鉀的釋放速率比NPK處理低18.3%,比試驗前土壤低26.7%;該處理土壤的非交換性鉀累積釋放量(133.32mg/kg)僅占NPK釋放量的78.69%;化肥配施秸稈土壤非交換性鉀釋放量為176.26mg/kg,釋放速率為16.13mg/kg·h~(-1)略高于氮磷鉀施肥,秸稈還田能夠提高紫色土供鉀能力.
[Abstract]:The total release and release rate of non-exchangeable potassium in soil are important indexes of soil potassium supply capacity. In this paper, the continuous extraction method of CaCl2 was used to study the application of potassium fertilizer without potassium fertilizer (CK), NP (without potassium fertilizer), NPK (for 22 years. Effects of NPKS (combined application of potassium fertilizer and straw) and S (single application of straw) on non-exchangeable potassium release characteristics of purple soil in order to provide scientific basis for potassium management of purple soil. The results showed that the release of non-exchangeable potassium from purple soil was characterized by rapid release in the early stage and slow and steady release in the later stage. Four kinds of kinetic equations were used to simulate the release process of exchanging potassium in purple soil. It was found that the Elovich equation (logarithmic curve equation) was the best in the early rapid release stage (1 鈮，

本文編號：2483171