Wind Erosion Modification in the Reversion Process of Desertification in the Middle Reaches of Shiyang River
Wind erosion is an important factor causing desertification and sand storms in arid and semi-arid regions.Mobile sand dunes and desertified lands closed for 5,15 and 25 years were selected as a restoration series in the reversion process of desertification to reveal changing characteristics of wind erosion in the middle reaches of Shiyang River.The results showed that the percentage of wind eroded area reduced from 100% on the mobile sand dunes to 80%, 9% and 2% on the desertified lands closed for 5, 15 and 25 years respectively.When the average wind velocity at 2 m height reached 6.5m/s, the sand transport rate reduced from 28.59g/cm2 ·h at mobile sand dunes to 0.91g/c2·h on the desertified land closed for 5 years, and almost to zero on the desertified lands closed for 15 and 25 years.An increase in ground roughness, reduction of near-surface wind velocity, and increased soil shear strength with the restoration of soil and vegetation were essential reasons for reduction of wind erosion.Compared with the mobile sand dunes, after 25-yearrestoration, the ground roughness increased by over 5000 times, the wind velocity within the 20 cmheight decreased by 83.68% ,and the soil shear strength increased by 30.1 times.The results can provide a theoretical basis for wind erosion control and support ecological restoration practices of the desertified land in arid inland river basins.
wind erosion desertified land sand-binding vegetation
Quanlin Ma Yaolin Wang Dekui Zhang Hujia Jin Baoli Fan Fang Cheng Youjun Liu
Gansu Key Laboratory of Desertification Combating,Gansu Desert Control Research Institute,Lanzhou 730070,China
国内会议
甘肃武威
英文
65-72
2013-07-12（万方平台首次上网日期，不代表论文的发表时间）