The dramatic changes and anthropogenic causes of erosion and deposition in the lower Yellow (Huanghe) River since 1952

The Yellow River has been considerably altered over the past half century from human activities. These perturbations provide a rare opportunity to document how this natural system has responded to anthropogenic impacts on channel hydrodynamics. Using a six-decade record data set, I analyze and summarize changing patterns in erosion and sedimentation of a downstream channel with three units (km3/y, Gt/y, and cm/y), and the response to human impacts upstream. The changing pattern of channel-bed erosion and deposition in the lower reach during 1952–2007 is divided into five phases in terms of erosion and deposition rates and human activities: (1) a rapid and quasi-natural deposition phase (1952–1959, 0.25 km3/y or 10 cm/y) with few main human effects, (2) a rapid erosion phase (1960–1964, − 0.36 km3/y or − 14 cm/y) in response to heavy sedimentation in the Sanmenxia reservoir, (3) a rapid deposition phase (1965–1973, 0.32 km3/y or 13 cm/y) in response to sediment release from the Sanmenxia reservoir, (4) a moderate erosion and deposition phase with a net deposition (1974–1999, 0.10 km3/y or 4 cm/y) in response to the Sanmenxia reservoir practice of storing clear water and discharging turbid water since 1974 and the intensified soil and water conservation since the 1970s, and (5) a slow erosion phase (2000–2007, − 0.15 km3/y or − 6 cm/y) in response to the water and sediment regulation and the initial operation of Xiaolangdi reservoir. The total reduction in sediment delivery by this river is 41.0 Gt (giga tons) during 1959–2007. The sediment delivery reduction are dams and reservoirs (51%), soil and water conservation (25%), increased water consumption (19%), and channel sedimentation (13%).