Research of Runoff and Sediment Yields on Different Slopes of Lancang River Arid Valley Under Natural Rainfall Conditions

Water, Journal Year: 2025, Volume and Issue: 17(7), P. 997 - 997

Published: March 28, 2025

Limited by water and heat conditions, the southwest alpine valley area has a dry climate, complex terrain, low vegetation coverage, very fragile ecological environment. The runoff plots of different slope gradients (10°, 15°, 20°), lengths (2, 5, 10 m) reverse terrace (RST) in Lancang River arid were taken as objects. Through situ observation sediment yield six natural erosive rainfalls, contribution rate factors was quantified, effect mechanism revealed. main results follows: (1) Sediment yields rainfalls closely correlated with rainfall type duration. Under conditions heavy rain (rain II III), there critical gradient, maximum achieved when gradient 15°. (2) reduction benefits horizontal terraces 24.88% 46.25%, these increased 1.47 times 1.30 after setting RST, significantly increase number RSTs (p < 0.05). (3) In this study, intensity contributed most to (34.5%), followed length (15.1%) (7.2%). Slope length, intensity, order 25.9%, 18.0%, 11.4% rate, respectively. (4) There significant linear correlation between on slopes decreased RST (2.91 times), it numbers. This study can provide scientific basis reference for prevention control soil loss restoration canyon area.

Language: Английский

Assessment of Erosive Rainfall and Its Spatial and Temporal Distribution Characteristics: Case Study of Henan Province, Central China

Water, Journal Year: 2024, Volume and Issue: 17(1), P. 62 - 62

Published: Dec. 29, 2024

Erosive rainfall is essential for initiating surface runoff and soil erosion to occur. The analysis on its temporal spatial distribution characteristics crucial calculating erosivity, predicting erosion, implementing water conservation. This study utilized daily observation data from 90 meteorological stations in Henan 1981 2020, conducted geostatistical analysis, M-K mutation test wavelet erosive reveal the spatiotemporal over past 40 years. Building this foundation, correlation between rainfall, erosivity were further explored. findings indicated that average annual Province varied 217.66 mm 812.78 mm, with an yearly of 549.24 a standard deviation 108.32 mm. constitutes 77% average, found highly correlated volume. increased northwest southeast, had same as total rainfall. number days was 20.5 sub-erosive 26.86 ranged 1341.81 6706.64 MJ·mm·ha−1·h−1, averaging at 3264.63 MJ·mm·ha−1·h−1. Both are influenced by monsoon, showing unimodal trend, majority attributed June September, amounting 80%. results can provide basis forecasting heavy events, conservation planning, ecological treatment, restoration.

Language: Английский