水保所知识产出(1956---)知识库

The loessial tableland is a unique landform type on the Loess Plateau in China. Long-term
soil erosion has led to the retreat of gullies and the rapid reduction of fertile arable land, which has
further decreased agricultural production. In this study, we chose the Malian River basin to analyze
the temporal and spatial variation of its runoff and sediment load, as well as the potential causes.
The annual runoff and sediment load at six hydrological stations in the study area were collected for
the period between 1960 and 2016. The Mann − Kendall and Pettitt tests were respectively applied to
detect temporal variations and abrupt changes in the runoff and sediment loads. The results showed
that an abrupt change in the runoff and sediment loads occurred in 2003. The average annual runoff
in the Malian River was 4.42 × 10 8 m 3 yr − 1 from 1960 to 2002, and decreased to 3.32 × 10 8 m 3 yr − 1 in
2003–2016. The average annual sediment load was 1.27 × 10 8 t yr − 1 in 1960–2002, and decreased to
0.65 × 10 8 t yr − 1 in 2003–2016. The spatial patterns in the sediment load suggested that the Hongde
sub-basin contributed a higher sediment count to the Malian River, which may require additional
attention for soil and water conservation in the future. Anthropogenic activities significantly affected
runoff and sediment load reduction according to the double-mass curve method, accounting for
90.7% and 78.7%, respectively, whereas rainfall changes were 9.3% and 21.3%, respectively. As such,
the present study analyzed the loessial tableland runoff and sediment load characteristics of the
Malian River basin for soil and water erosion management.