College of Land and Environment, Shenyang Agricultural University, Shenyang, 110866, China; Rural Energy and Environment Agency, Ministry of Agriculture and Rural Affairs, Beijing 100125, China.
Tillage and Cultivation Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang, 110161, China; National Agricultural Experimental Station for Agricultural Environment, Fuxin, 123102, China.
Chemosphere. 2023 Oct;337:139280. doi: 10.1016/j.chemosphere.2023.139280. Epub 2023 Jun 27.
The use of biodegradable plastic film mulching as a replacement for polyethylene plastic film has gained recognition due to its reduced environmental pollution. However, its impact on soil environment is not yet fully understood. Here, we compared the effects of different plastic film mulching on the accumulation of microbial necromass carbon (C) and its contribution to soil total C in 2020 and 2021. Results showed that biodegradable plastic film mulching decreased the accumulation of fungal necromass C compared to no plastic film mulching and polyethylene film mulching. However, the bacterial necromass C and soil total C were not affected by the plastic film mulching. Biodegradable plastic film mulching decreased the soil dissolved organic carbon content after maize harvest. Random forest models suggested that soil dissolved organic C, soil pH and the ratio of soil dissolved organic C to microbial biomass C were important factors in regulating the accumulation of fungal necromass C. The abundance of the fungal genus Mortierella was also found to have a significant positive contribution to the accumulation of fungal necromass C. These findings suggest that biodegradable plastic film mulching may decrease the accumulation of fungal necromass C by changing substrate availability, soil pH, and fungal community composition, with potential implications for soil C storage.
可生物降解塑料薄膜覆盖作为聚乙烯塑料薄膜的替代品已经得到认可，因为它可以减少环境污染。然而，其对土壤环境的影响尚未完全了解。在这里，我们比较了不同塑料薄膜覆盖对微生物残体碳（C）积累及其对土壤总 C 的贡献的影响，结果表明，与不使用塑料薄膜覆盖和聚乙烯薄膜覆盖相比，可生物降解塑料薄膜覆盖减少了真菌残体 C 的积累。然而，细菌残体 C 和土壤总 C 不受塑料薄膜覆盖的影响。可生物降解塑料薄膜覆盖会降低玉米收获后土壤溶解性有机碳的含量。随机森林模型表明，土壤溶解性有机碳、土壤 pH 值以及土壤溶解性有机碳与微生物生物量 C 的比值是调节真菌残体 C 积累的重要因素。真菌属 Mortierella 的丰度也被发现对真菌残体 C 的积累有显著的正贡献。这些发现表明，可生物降解塑料薄膜覆盖可能通过改变基质可用性、土壤 pH 值和真菌群落组成来减少真菌残体 C 的积累，这可能对土壤 C 储存有影响。
