Evaluating of Sediment Delivery Ratio on Spatial and Temporal Variabilities in Semiarid Watershed Brazil

Abstract

Evaluation of sediment delivery ratio is important for determining watershed sediment yield. Rates of both interrill and rill erosion were calculated under shrub and uncovered Inceptisols conditions and were not observed to the presence by ravines and gullies in the watershed of Jacu River, in a semiarid region, Brazil. Direct measurement campaigns of suspended sediment and bedload were also carried out by means of the US DH-48 for collection of suspended sediment samples and US BLH-84used to collect samples bed load. The soil loss due to interril erosion under uncovered conditions was equal to 8.43 t ha-1 and was considered high, and the same was true for the values of rill erosion with erodibility equal to 0.0021142 kg N-1 s-1 and critical shear stress (τc) equal to 2.34 Pa. The mean value of sediment delivery ratio of Jacu watershed was equal to 0.165 and ranged from 0.29 in the year 2008 to 0.026 in 2010. This variation was associated with the natural variability of semiarid environment, indicating the necessity of assessment for a longer period to deepen our knowledge of sediment delivery ratio of the Jacu semiarid watershed.

Application of statistical control on water quality in cisterns in the semiarid Pernambucano

“…However, vegetation cover is often removed, and agriculture without erosion control is implemented, promoting runoff in the rainy season, transporting sediment, and adsorbed nutrients that contribute to siltation and eutrophication of downstream rivers and dams (Silva et al, 2015). However, dry season water scarcity associated with evapotranspiration's natural process leads to low dilution capacity, which may result in extreme deterioration of water quality and elimination of natural biological communities (Piscoya et al, 2018).…”