Dynamics of Sediment Transport in the Teles Pires River Basin in the Cerrado-Amazon, Brazil

Abstract

The Teles Pires River basin is experiencing significant water challenges due to recent urban growth, expansion of irrigated agriculture, and the rise of hydroelectric power plants in Brazil’s forest and savanna regions, impacting water availability and sediment production. This study evaluated and estimated the production of suspended sediment (Qss) and total sediment (Qst) in rivers and streams of the Teles Pires River basin, using different sampling methods for suspended-solid discharge: vertical sampling (reference), composite sampling (section), sampling along the standard vertical, and sampling along three verticals, collected using the equal-width increment method. The Qss and Qst values varied from 0.31 to 39.35 metric tons (t) per day (d−1) and from 0.32 to 43.70 t d−1, respectively. The average percentages of the entrained solid discharge varied from 3 to 5%, between the dry and rainy seasons, and across all hydrological sections. The different sampling methods of Qss resulted in similar Qst in each of the monitoring sections. The statistical performance of the simple linear regression model was satisfactory with Willmott index of agreement greater than 0.8234 and 0.9455 for estimates of Qss and Qst, respectively. The dynamics of sediment production and transport was influenced by land use and cover, drainage area, and the hydrological seasonality of the region. The different sampling methods of Qss are compatible with obtaining suspended and total solid discharge; however, the standard vertical sampling is the most simplified and can be applied in a hydrological section with uniform hydraulic conditions.