Porter Matthew D, Andrus J Malia, Bartolerio Nicholas A, Rodriguez Luis F, Zhang Yuanhui, Zilles Julie L, Kent Angela D
Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
Environmental Resources Management, 1701 Golf Road, Suite 1-700, Rolling Meadows, IL, 60008, USA.
Microb Ecol. 2015 Oct;70(3):710-23. doi: 10.1007/s00248-015-0605-8. Epub 2015 Apr 26.
Denitrifying bioreactors, consisting of water flow control structures and a woodchip-filled trench, are a promising approach for removing nitrate from agricultural subsurface or tile drainage systems. To better understand the seasonal dynamics and the ecological drivers of the microbial communities responsible for denitrification in these bioreactors, we employed microbial community "fingerprinting" techniques in a time-series examination of three denitrifying bioreactors over 2 years, looking at bacteria, fungi, and the denitrifier functional group responsible for the final step of complete denitrification. Our analysis revealed that microbial community composition responds to depth and seasonal variation in moisture content and inundation of the bioreactor media, as well as temperature. Using a geostatistical analysis approach, we observed recurring temporal patterns in bacterial and denitrifying bacterial community composition in these bioreactors, consistent with annual cycling. The fungal communities were more stable, having longer temporal autocorrelations, and did not show significant annual cycling. These results suggest a recurring seasonal cycle in the denitrifying bioreactor microbial community, likely due to seasonal variation in moisture content.
反硝化生物反应器由水流控制结构和填充木屑的沟渠组成，是从农业地下或瓦管排水系统中去除硝酸盐的一种很有前景的方法。为了更好地了解这些生物反应器中负责反硝化作用的微生物群落的季节动态和生态驱动因素，我们在两年的时间里对三个反硝化生物反应器进行了时间序列检测，采用微生物群落“指纹识别”技术，研究细菌、真菌以及负责完全反硝化作用最后一步的反硝化功能菌群。我们的分析表明，微生物群落组成对生物反应器介质的深度、水分含量和淹没情况的季节变化以及温度有响应。使用地统计分析方法，我们观察到这些生物反应器中细菌和反硝化细菌群落组成存在反复出现的时间模式，与年度循环一致。真菌群落更稳定，具有更长的时间自相关，并且没有显示出明显的年度循环。这些结果表明反硝化生物反应器微生物群落存在反复出现的季节性循环，可能是由于水分含量的季节变化所致。
