Author(s): Shuqing Nan, Jia Li, Linlei Zhang
Linked Author(s): Jia LI
Keywords: Yarlung Zangbo River, hydrological parameter, TP, transport
Abstract:
Phosphorus is one of the necessary nutrition elements for biological growth, and its transport and variation properties can reflect the evolution process of aquatic ecological environment. With the special geographic climate characteristics of the plateau river, Yarlung Zangbo River (YZR) is unique in rainfall, runoff, sediment transport, water temperature variation, etc., which facilitate the formation of the special dynamic process of total phosphorus (TP) transport. The results show that the TP concentration of single measurement for years in the main stream of YZR is within ND-0.32 mg/L, and the annual average value of various points is between 0.015 mg/L and 0.13 mg/L. In the time scale, the TP concentration curve has the unimodal shape in a year. The variation process is synchronous with the runoff and sediment. That is to say, the peak value appears in wet season and the valley value appears in dry season, and the maximum peak-to-valley ratio is 64, which is different from Huaihe River and other inland rivers. In the space scale, the TP concentration along the main stream of YZR mostly reaches to the maximum value with the confluence of Lhasa River. From the point of view of the transport flux level, the average monthly TP flux at different points varies from 0.036 to 0.143 kg/s. The Pearson correlation analysis shows that the TP concentration has a higher degree of correlation with other factors, and the correlation coefficient varies from 0.509 to 0.959. The correlation degree with suspended sediment discharge is the largest, and with flow rate is the second. The distributions of TP in particle state and dissolved state show that the TP in the main stream of YZR is mainly from the non-point source, and runoff and sediment are the main controlling factors of its transport. (2605, 78, 318)
Year: 2017