Different film-mulching strategies alter soil biological characteristics and fungal and archaeal community structures under a drip fertigation system

Abstract

Soil microorganisms play a crucial role in ecosystem succession. Thus, understanding the responses of microbial communities during film mulching with drip fertigation is essential. This study employed high-throughput sequencing to evaluate soil biological characteristics and the community composition, diversity, and potential ecological functions of fungi and archaea in a semi-arid region under drip fertigation with the following film mulching treatments: drip irrigation without mulching (DI), polyurethane film mulching (PF), and biodegradable film mulching (DF).The biodegradable film used in this study was composed of maize-specific poly (propylene carbonate), high molecular weight polyester, chain extenders, and layered nanofillers. Results demonstrated that, compared to PF, DF significantly enhanced microbial biomass carbon (MBC) by 8.4 %, microbial biomass nitrogen (MBN) by 17.1 %, and basal respiration (BR) by 10.6 %. Both DF and PF significantly increased soil sucrase (S-SC) activity, while reducing soil laccase (SL) and catalase (S-CAT) activities. Specifically, compared to DI, DF increased S-SC by 13.7 % and PF increased it by 20.3 %. Moreover, DF and PF significantly altered the fungal and archaeal community compositions and diversity. Specifically, DF exhibited a lower Shannon index for both fungi and archaea compared to PF, with a reduced relative abundance of potentially pathogenic microorganisms (Fusarium, Leptosphaeria, Pseudomonas, and Acidovorax) and an increased relative abundance of potentially beneficial microorganisms (Powellomyces, Penicillium, and Methanosarcina). Structural equation modeling (SEM) revealed that soil pH and MBC were the primary drivers of fungal and archaeal community alterations, respectively. Network analysis further indicated that DF promoted more stable fungal co-occurrence networks, enhancing resistance to environmental perturbations, while fostering stronger species interactions within archaeal co-occurrence networks. This study highlights the pivotal role of biodegradable film mulching in optimizing soil ecological environments and promoting sustainable agriculture, providing scientific evidence for improved agricultural management strategies.