Interpretation of the environmental change of Dongting Lake, middle reach of Yangtze River, China, by 210Pb measurement and satellite image analysis

摘要: Abstract The present study examined the recent environmental history of Dongting Lake, located in middle Yangtze River region, central China. sediment was recovered by 22 vibrocores different lake sectors, primarily characterizing subaqueous delta and bay subfacies. High sedimentation rates, revealed 210Pb measurement subfacies lake, ranged from 0.77 to 2.33 cm/year. These rates equate deltaic associated with mobile channels resulting flood events. Satellite images confirm that Lake does not contain biggest floods. Moreover, comparative bathymetric surveys verify has lost almost two-thirds its total area past century, due siltation sediment. In late 19th a major flood-induced channel avulsion resulted coupling ‘Four-Tributary’ subbasin causing massive increase supply into since then. Hydrological data demonstrate about 83% lake's annual influx are derived Yangtze. addition, pressures growing population human activities, such as reclamation, embanking, aquaculture, slope modification deforestation, compounding loss surface storage capacity.