Impact of a Single Lignite Humic Acid Application on Soil Properties and Microbial Dynamics in Aeolian Sandy Soils: A Fourth-Year Study in Semi-Arid Inner Mongolia

作者：Lei Zhou, Junqi Chu, Yufen Zhang, Qi Wang, Yanting Liu, Baoping Zhao · 发表于：Agronomy · 年份：2024 · DOI：10.3390/agronomy14112581 · 被引用次数：6 · 研究领域：Soil Carbon and Nitrogen Dynamics、Coal and Its By-products、Agronomic Practices and Intercropping Systems

Humic acid (HA) is considered a promising soil amendment for improving soil fertility. However, the effects of HA application on the microbial community, especially in aeolian sandy soils of semi-arid regions, remain insufficiently elucidated. To address this gap, a field experiment was conducted to investigate the changes in soil properties, bacterial and fungal diversity, and community structure in a buckwheat field in the fourth year after a single application of lignite humic acid (L-HA) at 0 (L-HA0), 2 (L-HA1), 4 (L-HA2), and 6 (L-HA3) ton·ha−1 in an aeolian sandy soil in Inner Mongolia, China. The results demonstrated that four years after L-HA application, there was a significant (p < 0.05) decrease in soil pH, accompanied by an increase in soil water content and nutrient levels, including organic matter and total N, available P, and K. Additionally, the application of L-HA enhanced microbial biomass C and N and stimulated enzyme activities, such as urease and invertase, with these effects being more pronounced at higher application rates (L-HA2 and L-HA3). However, HA addition did not significantly (p < 0.05) affect soil microbial biomass P or alkaline phosphatase activity. The L-HA amendment enhanced the α-diversity indices of soil bacteria but did not significantly (p < 0.05) affect soil fungal diversity. The addition of L-HA induced significant changes in the composition of the soil microbial community at both the phylum and genus levels, with significant ...