Hu Yinhong, Dou Xiaolin, Li Juanyong, Li Feng
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China.
Front Microbiol. 2018 Feb 27;9:226. doi: 10.3389/fmicb.2018.00226. eCollection 2018.
The rapid expansion of urbanization has caused land cover change, especially the increasing area of impervious surfaces. Such alterations have significant effects on the soil ecosystem by impeding the exchange of gasses, water, and materials between soil and the atmosphere. It is unclear whether impervious surfaces have any effects on soil bacterial diversity and community composition. In the present study, we conducted an investigation of bacterial communities across five typical land cover types, including impervious surfaces (concrete), permeable pavement (bricks with round holes), shrub coverage (), lawns (), and roadside trees () in Beijing, to explore the response of bacteria to impervious surfaces. The soil bacterial communities were addressed by high-throughput sequencing of the bacterial 16S rRNA gene. We found that , , , , , and were the predominant phyla in urban soils. Soil from impervious surfaces presented a lower bacterial diversity, and differed greatly from other types of land cover. Soil bacterial diversity was predominantly affected by Zn, dissolved organic carbon (DOC), and soil moisture content (SMC). The composition of the bacterial community was similar under shrub coverage, roadside trees, and lawns, but different from beneath impervious surfaces and permeable pavement. Variance partitioning analysis showed that edaphic properties contributed to 12% of the bacterial community variation, heavy metal pollution explained 3.6% of the variation, and interaction between the two explained 33% of the variance. Together, our data indicate that impervious surfaces induced changes in bacterial community composition and decrease of bacterial diversity. Interactions between edaphic properties and heavy metals were here found to change the composition of the bacterial community and diversity across areas with different types of land cover, and soil properties play a more important role than heavy metals.
城市化的快速扩张导致了土地覆盖变化，尤其是不透水表面面积的增加。这种变化通过阻碍土壤与大气之间的气体、水和物质交换，对土壤生态系统产生重大影响。目前尚不清楚不透水表面是否对土壤细菌多样性和群落组成有任何影响。在本研究中，我们对北京五种典型土地覆盖类型（包括不透水表面（混凝土）、透水路面（圆孔砖）、灌木覆盖地、草坪和路边树木）的细菌群落进行了调查，以探索细菌对不透水表面的响应。通过对细菌16S rRNA基因进行高通量测序来分析土壤细菌群落。我们发现， 、 、 、 、 和 是城市土壤中的优势菌门。不透水表面的土壤细菌多样性较低，且与其他土地覆盖类型差异很大。土壤细菌多样性主要受锌、溶解有机碳（DOC）和土壤含水量（SMC）的影响。灌木覆盖地、路边树木和草坪下的细菌群落组成相似，但与不透水表面和透水路面下的不同。方差分解分析表明，土壤性质对细菌群落变异的贡献率为12%，重金属污染解释了3.6%的变异，二者之间的相互作用解释了33%的变异。总之，我们的数据表明不透水表面导致了细菌群落组成的变化和细菌多样性的降低。我们发现，土壤性质和重金属之间的相互作用改变了不同土地覆盖类型区域的细菌群落组成和多样性，且土壤性质比重金属发挥着更重要的作用。
