Micro - Nano Bubble Technology- An In-Situ Treatment for Microbial Community Changes in Urban River

Urban watercourses are essential and important to the urban ecosystem, landscape ecology and citizen’s life. However, in recent decades, rapid industrialization and urbanization has accelerated the worsening waters in urban area in China. Urban rivers are usually used as drains for sewage, industrial wastewater and even domestic garbage, which contained various pollutants. When organic pollutants are discharged to rivers, part of them is precipitated in the sediment and the others are metabolized by microbes. During the metabolism, the microbes exhaust the dissolved oxygen in the water and make the aquatic environment anoxic, which promotes the growth of anaerobic microbes. As a result, the river is in anoxic condition, showing black appearance and stinking smell. These black-odor rivers flows through the cities affect residents’ life and pose a serious threat to human health. During the metabolism, the microbes exhaust the dissolved oxygen in the water and make the aquatic environment anoxic, which promotes the growth of anaerobic microbes. As a result, the river is in anoxic condition, showing black appearance.