Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of the Chinese Academy of Sciences, Beijing 100049, China.
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Sci Total Environ. 2019 Mar 15;656:750-759. doi: 10.1016/j.scitotenv.2018.11.438. Epub 2018 Nov 29.
Biodegradable plastics have been widely introduced into agricultural production, but their impacts on the soil ecosystem remain unclear. The present study investigated the impacts of a biodegradable seedling tray (BST) on the microbial communities in paddy soils. A 110-day rice culture experiment was conducted with three different paddy soils developed from black soil (BS, black chernozem soil), chao soil (CS, Fluvo-aquic) and red soil (RS, Alfisols) and three application rates of BST (0, 0.02 and 0.2 g kg). Soil phthalic acid ester (PAE) concentrations, physicochemical properties and enzyme activities were determined to evaluate the influence of BSTs on soil quality. 16S high-throughput sequencing was used to study bacterial community composition and the Biolog EcoPlate™ test was used to profile microbial activity and community function. Results show that the application of BSTs did not markedly affect soil quality, and the potential release of PAEs from BSTs was negligible. Interestingly, the microbial community was affected by BSTs in a soil-dependent and time-dependent pattern. The microbial community in RS was not significantly influenced by BSTs. Relative abundances of some predominant genera in BS (e.g. norank_f__BSV40) and CS (e.g. Norank_f__Nitrosomonadaceae) were significantly influenced by BSTs, and db-RDA results show that community composition in BS and CS was shaped mainly by BSTs. Community level profiling shows that BSTs significantly increased microbial activity and decreased functional diversity in BS after 55 days, but the impacts disappeared after 110 days. The results contribute to the knowledge of how biodegradable plastics influence microbial communities in paddy fields and provide information relevant to the practical use of BSTs under field condition.
可生物降解塑料已广泛应用于农业生产，但它们对土壤生态系统的影响尚不清楚。本研究调查了可生物降解育苗盘（BST）对稻田土壤微生物群落的影响。采用黑土（BS，黑钙土）、潮土（CS，冲积-沼泽土）和红壤（RS，淋溶土）三种不同母质发育的稻田土，进行了为期 110 天的水稻栽培实验，BST 施用量分别为 0、0.02 和 0.2 g kg-1。测定土壤邻苯二甲酸酯（PAE）浓度、理化性质和酶活性，以评估 BST 对土壤质量的影响。采用 16S 高通量测序研究细菌群落组成，采用 Biolog EcoPlate™ 试验分析微生物活性和群落功能。结果表明，BST 的应用并未显著影响土壤质量，BST 中 PAE 的潜在释放可忽略不计。有趣的是，微生物群落受 BST 的影响具有土壤依赖性和时间依赖性。BST 对 RS 土壤中的微生物群落没有明显影响。BS（例如，unrank_f__BSV40）和 CS（例如，Norank_f__Nitrosomonadaceae）中的一些主要属的相对丰度受 BST 的显著影响，db-RDA 结果表明，BS 和 CS 中的群落组成主要由 BST 决定。群落水平分析表明，BST 显著增加了 BS 中微生物的活性，并在 55 天后降低了功能多样性，但 110 天后这种影响消失了。研究结果有助于了解可生物降解塑料如何影响稻田中的微生物群落，并为 BST 在田间实际应用提供相关信息。
