Distinct temporal succession patterns of soil microbial communities under multi-source compost and chemical...

Understanding the temporal succession of soil microbial communities under multi-source composts and chemical fertilizer (CF) is critical for sustainable agriculture. This study investigated the effects of CF and composts derived from cow dung (CD), chicken manure (CM), and food waste (FW) on soil microbial community over 360 days. Composts application enhanced soil microbial diversity with distinct temporal patterns: FW provided consistent enrichment, CD caused cyclical fluctuations, and CM produced delayed positive effects. CF persistently reduced diversity and created unique ecological niches of bacteria. Microbial communities exhibited clear directional shifts over time, with key transition points at day 14 (shift to active restructuring) and day 150 (onset of stabilization). Besides, CM enriched cellulose- and hemicellulose-degrading microbes; CD promoted C/N-cycling and mutualistic microbes; FW increased nutrient-transforming functional bacteria as well as some risk-associated taxa. CF restructured the microbial community by enriching nitrogen-cycling specialists. Temporal biomarkers indicated a shift from copiotrophic to oligotrophic taxa, with 17 early abundant genera declining over time, likely contributing to necromass accumulation. Furthermore, compost fostered more complex and resilient microbial networks with greater functional diversity, whereas CF simplified community structure despite higher connectivity. Over time, networks showed fewer nodes and phased fluctuations in topology, reflecting functional reorganization from early competitive interactions toward later synergistic associations. These dynamics were linked to depletion of DOC and NH₄⁺-N and accumulation of TN and NO₃^--N, causing structural simplification but tighter topological connectivity. Overall, the results emphasize the need for source-specific compost strategies to optimize soil ecosystem services.