Causes of Variations in Sediment Yield in the Jinghe River Basin, China

Abstract

The Jinghe River remains the major sediment source of the Yellow River in China; however, sediment discharge in the Jinghe River has reduced significantly since the 1950s. The objective of this study is to identify the causes of sediment yield variations in the Jinghe River Basin based on soil and water conservation methods and rainfall analyses. The results revealed that soil and water conservation projects were responsible for half of the total sediment reduction; sediment retention due to reservoirs and water diversion projects was responsible for 1.3% of the total reduction. Moreover, the Jinghe River Basin has negligible opportunity to improve its vegetation cover (currently 55% of the basin is covered with lawns and trees), and silt-arrester dams play a smaller role in reducing sediment significantly before they are entirely full. Therefore, new large-scale sediment trapping projects must be implemented across the Jinghe River Basin, where heavy rainfall events are likely to substantially increase in the future, leading to higher sediment discharge.

Intra-annual sediment dynamic assessment in the Wei River Basin, China, using the AIC functional-structural connectivity index

“…This concurs with the observations and estimations of sediment discharge in these areas. Despite the implementation of various soil and water conservation works in the Jing sub-basin since the 1950 s, the Jing River is still a major sediment source of the Yellow River (Zhang et al, 2020), with an annual sediment transport modulus of Jing sub-basin of 4,776 t/km 2 et al, 2021). On the other the Grain for Green project has greatly improved the vegetation cover in the Beiluo sub-basin (Chen et al, 2016), and the average soil erosion modulus of Beiluo sub-basin in 2009 ~ 2018 has been calculated at 358.33 t/(km 2 •a) (Hao et al, 2020).…”

Effects of single‐ and multi‐site calibration strategies on hydrological model performance and parameter sensitivity of large‐scale semi‐arid and semi‐humid watersheds

“…Most of the linear fitting lines between the measured and simulated monthly runoff of the three hydrological stations are below the 1:1 straight line during the calibration and validation period (Figure 3), indicating that the measured runoff tends to be greater than the simulated runoff in the calibration and validation period. This phenomenon can be attributed to the scarcity of precipitation in the Jinghe River Watershed during the dry period; the stormflow in the dry season primarily comes from the recharging of groundwater (Zhang, Shang, et al, 2020a). The R 2 of three sites in the calibration period are all greater than that of the validation period, of which Zhangjiashan station has the maximum R 2 value of 0.8286, indicating that the scatterplots in the calibration period of the Zhangjiashan station have good linear fitting performance.…”

“…Watershed during the dry period; the stormflow in the dry season primarily comes from the recharging of groundwater (Zhang, Shang, et al, 2020a). The R 2 of three sites in the calibration period are all greater than that of the validation period, of which Zhangjiashan station has the maximum R 2 value of 0.8286, indicating that the scatterplots in the calibration period of the Zhangjiashan station have good linear fitting performance.…”

A framework for modelling emergent sediment loss in the Ombrone River Basin, central Italy

“…35.9 Pg yr −1 2012), mainly driven by land-use changes, such as the decline of forests and the expansion of semi-natural vegetation and cropland [23]. In addition, hydrological systems in different river basins worldwide have come under increasing pressure on land resources due to urbanisation and poor land management practices [24], as well as changes in precipitation patterns [25].…”