ABSTRACT
Liu River Basin lies in semi-arid monsoon climate zone where characterized by sparse vegetation, infertile soil, strong wind and water erosion. In this basin, mountain area accounts for 43%, followed by hills of 32%, sand dunes of 15%, and plains of 10% respectively. Liu River is destined to be a sandy river because of its specific underlying surface characteristics (e.g geology, soil type, topography), also combined by human activities such as land reclamation, forests and grass destruction, overgrazing, and etc. Mean annual runoff of Liu River is only 281 million m3, but its multi-year average sediment concentration is quite high, up to 19.58 kg/m3 at Xinmin station. According to monitoring data, more sediment discharge at Naodehai station located in upstream of Xinmin station, with annual average load of 13,859,700 t/a and sediment concentration of 51.59 kg/m3 from 1954 to 2004. Thus, the sediment in Liu River mainly originates from the upstream region of Naodehai. Based on previous research of Liu River, vast sediment accumulated in the riverbed from Naodehai to Xinmin, thereby forming a “suspend river”. Sediment deposition has been seriously endangered flood safety of the river surrounding regions. In this paper, analysis was firstly conducted on the distribution and possible sources of sediments in Liu River. Based on these analysis, sediment regulation advices and approaches were proposed from the aspects of controlling slope erosion, managing channel erosion and building reservoirs.
