Soil Organic Carbon Accumulation and Stability Under Rice Straw, Ash, and Biochar Amendment in Saline-Alkali Soil

Abstract

Salinization and alkalization contribute significantly to soil degradation. Rice (Oryza sativa L.) cultivation is an effective approach to remediate saline-alkali soil. However, how rice straw (RS), rice straw biochar (RSB), and rice straw ash (RSA) impact soil organic carbon (SOC) accumulation and stability in saline-alkali soil remains unknown. Herein, SOC and SOC fractions contents in bulk soil and its particle- and aggregate-size classes under RS, RSB, and RSA amendments and control with amendments (CK) were investigated by field experiment. Carbon-13 nuclear magnetic resonance spectroscopy was used to evaluate bulk SOC chemical composition. The SOC and SOC fractions contents ranked as CK