Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China.
Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
Sci Rep. 2017 Mar 10;7:44049. doi: 10.1038/srep44049.
Transition of populations from rural to urban living causes landscape changes and alters the functionality of soil ecosystems. It is unclear how this urbanization disturbs the microbial ecology of soils and how the disruption influences nitrogen cycling. In this study, microbial communities in turfgrass-grown soils from urban and suburban areas around Xiamen City were compared to microbial communities in the soils from rural farmlands. The potential NO emissions, potential denitrification activity, and abundances of denitrifiers were higher in the rural farmland soils compared with the turfgrass soils. Ammonia oxidizing archaea (AOA) were more abundant than ammonia oxidizing bacteria (AOB) in turfgrass soils. Within turfgrass soils, the potential nitrification activities and AOA abundances were higher in the urban than in the suburban soils. These results indicate a more pivotal role of AOA in nitrification, especially in urban soils. Microbial community composition was distinctly grouped along urbanization categories (urban, suburban, and rural) classified according to the population density, which can in part be attributed to the differences in soil properties. These observed changes could potentially have a broader impact on soil nutrient availability and greenhouse gas emissions.
人口从农村向城市生活的迁移导致了景观变化，并改变了土壤生态系统的功能。目前尚不清楚这种城市化如何扰乱土壤的微生物生态，以及这种干扰如何影响氮循环。在这项研究中，比较了来自厦门市城区和郊区草坪土壤中的微生物群落与来自农村农田土壤中的微生物群落。与草坪土壤相比，农村农田土壤中的潜在 NO 排放、潜在反硝化活性和反硝化菌丰度更高。在草坪土壤中，氨氧化古菌 (AOA) 的丰度高于氨氧化细菌 (AOB)。在草坪土壤中，城市土壤的潜在硝化活性和 AOA 丰度高于郊区土壤。这些结果表明 AOA 在硝化作用中起着更关键的作用，尤其是在城市土壤中。根据人口密度对城市化类别（城市、郊区和农村）进行分类，微生物群落组成明显分为不同的组，这在一定程度上归因于土壤性质的差异。这些观察到的变化可能会对土壤养分供应和温室气体排放产生更广泛的影响。
