| 摘要: |
| 秸秆和地膜覆盖会改变农田土壤碳氮循环等理化条件，而覆盖对参与碳氮循环的土壤微生物的影响还鲜有报道。本研究通过高通量测序，分析了黄土高原旱作玉米农田无覆盖、秸秆覆盖、地膜覆盖下土壤细菌群落组成，探讨了细菌介导的碳氮循环对覆盖的响应。结果表明秸秆覆盖增加了土壤细菌群落丰富度和多样性，且显著增加了分解纤维素的细菌（纤维弧菌属Cellvibrio）及介导固氮（根瘤菌属Rhizomicrobium、Chryseolinea）和硝化过程的细菌（亚硝化螺菌属Nitrosospira）丰度（p＜0.05）；地膜覆盖增加了土壤细菌丰富度，但降低了细菌多样性，且显著增加了介导土壤硝化作用的硝化螺菌属Nitrospira的丰度（p＜0.05）。本结果为土壤中微生物介导的碳氮循环研究提供了理论依据。 |
| 关键词: 旱作农田 秸秆覆盖 地膜覆盖 细菌 碳氮循环 |
| DOI：10.7515/JEE192011 |
| CSTR： |
| 分类号: |
| 基金项目:国家自然科学基金项目（41303073）；陕西省青年科技新星计划项目（2016KJXX-83）；陕西省自然科学基础研究计划青年人才项目（2015JQ4101）；陕西省教育厅科学研究项目（14JK1731） |
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| Soil bacterial community structure in a dryland spring maize field with mulching |
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DING Liuyi, WANG Sen, FU Xin
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1. College of Urban and Environmental Sciences, Northwest University, Xi’an 710127, China
2. Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Northwest University, Xi’an 710127, China
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| Abstract: |
| Background, aim, and scope Straw and plastic film mulching will change the physical and chemical conditions such as carbon and nitrogen cycling in farmland soils, and few studies focused on the effects of covering soil microbes involved in carbon and nitrogen cycling. Consequently, in this paper we analyzed the bacterial community composition under different ways of mulching, and aimed at the microbial-mediated carbon and nitrogen cycling. Materials and methods In this study, the high-throughput sequencing technology was used to analyze the soil bacterial community composition in no mulching (CK), straw mulching (SM) and plastic film mulching (PM) spring maize in a dryland spring maize farmland on the Loess Plateau in China. Results The results showed that straw mulching increased the abundance and diversity of soil bacterial communities, and significantly increased the abundance of cellulolytic bacteria (Cellvibrio) and the bacteria with nitrogen fixation (Rhizomicrobium, Chryseolinea) and nitrification (Nitrosospira) (p＜0.05). Plastic mulching increased soil bacteria abundance but decreased soil bacteria diversity. and the plastic mulching significantly increased the abundance of Nitrospira with nitrification (p＜0.05). Discussion Mulching significantly increased carbon and nitrogen cycling-related microbes (Cellvibrio, Rhizomicrobium, Chryseolinea, Nitrosospira, and Nitrospira), and a positive correlation was found between soil total organic carbon, total nitrogen, potential mineralizable nitrogen and these microbes using redundancy analysis (p＜0.05), supporting the hypothesis that these microbes may play a major role in soil carbon and nitrogen cycling under straw and plastic mulching on the Loess Plateau. Conclusions Mulching increased the abundance soil bacteria, and affected the soil carbon and nitrogen. Cellvibrio, Rhizomicrobium, Chryseolinea, Nitrosospira, and Nitrospira may contribute greatly to soil carbon and nitrogen cycling under straw and plastic mulching in a dryland spring maize farmland. Recommendations and perspectivesThis result provides useful information for better studying the microbial-mediated carbon and nitrogen cycling in soil. |
| Key words: dryland field straw mulching plastic film mulching bacterial community carbon and nitrogen cycling |
