[Effects of Organic Materials Combined with Dolomite on Acidic Yellow Soil and Maize Growth].

Abstract

The problem of acidification of yellow soil in the southwest of China is prominent. To rejuvenate the new quality productive forces of acidic yellow soil， five treatments were set up： no amendment （CK）， organic fertilizer （OF）， biochar （BC）， biochar + dolomite （BC+D）， and organic fertilizer + dolomite （OF+D）. The aim was to identify a comprehensive improvement plan suitable for high-quality and long-term acidified yellow soil. The results showed that： ① OF+D significantly reduced exchangeable hydrogen by 25.9% and exchangeable aluminum by 34.1%， increased base saturation by 45.8% and pH by 0.43 units， and could promptly buffer the input of acidic substances near the root layer， reducing the sharp fluctuations in pH caused by the hydrolysis of potential acid， achieving the best acid control and prevention. ② BC and BC+D promoted the uniform distribution of soil water and nitrogen， while OF and OF+D were more effective in increasing water and nitrogen reserves. Particularly， OF+D increased total nitrogen， organic carbon， and available phosphorus by 9.1%， 12.4%， and 551.6%， respectively， while BC+D showed antagonistic effects. ③ The dry matter accumulation of corn was in the order of OF+D>BC+D>OF>BC>CK. The significant advantages were shown before the jointing stage after the application of dolomite， and the accumulation of grain biomass and nitrogen was accelerated thereafter. The yield， nitrogen uptake efficiency， and partial factor productivity of nitrogen of OF+D increased by 10.3%，73.8%， and 10.3%， respectively， and the production efficiency was improved in a coordinated manner. Therefore， considering the comprehensive aspects of acid regulation and control， soil fertility improvement， and stable and increased production， the application of organic fertilizer combined with dolomite is the most ideal approach for the improvement of acidic yellow soil and the increase of corn yield.