As a typical shallow lake of the middle and upper reaches of the Yangtze River, Honghu Lake had became eutrophic due to intensive aquaculture, industrialization and agricultural intensification over the past decades. To investigate the interaction and co-evolution between microorganisms and environmental factors, such as total C, total organic C and total N, a sediment core sample of 70 cm length has been obtained. This 0-70 cm sediment core corresponded to 117 years based on the isotopic geochronol...