Land | |
Root Distribution and Soil Properties of Gully Heads and Their Effects on Headcut Migration in the Mollisols Region of Northeast China | |
Xingyi Zhang1  Lixin Wang1  Jiarui Qi1  Zhuoxin Chen2  Jinzhong Xu3  Pengchong Zhou4  Mingming Guo4  | |
[1] College of Resources and Environment, Northeast Agriculture University, Harbin 150030, China;Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Xianyang 712100, China;Institute of Soil and Water Conservation, Heilongjiang Province Hydraulic Research Institute, Harbin 150080, China;Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin 150081, China; | |
关键词: gully erosion; land use; headcut retreat; root density; black soil region; | |
DOI : 10.3390/land11020184 | |
来源: DOAJ |
【 摘 要 】
Previous studies have proved that root distribution along gully headwalls greatly alters soil properties and further affects the soil erodibility of gully heads. However, it is not clear whether the gully headcut migration is affected by root distribution and soil properties. Five representative gullies developed in different land uses were selected to clarify the variations of root distribution and soil properties and their effects on headcut migration in the rainy season (May to October 2021) in the Mollisols region of northeast China. Results showed that the 68.4%–93.3% of root mass density and 65.6–88.5% of root length density were concentrated in 0–30 cm soil layer of gully heads, and the roots of <2.0 mm accounted for >85%. The gullies developed in farmlands had relatively higher soil compactness, shear strength and aggregate stability, but lower organic matter (OMC), disintegration capacity and soil permeability than those developed in woodlands, unpaved roads in farmland and stable gully-beds. Changes in soil properties of gully heads were closely related to root density. The linear, areal, and volumetric migration rate of gully heads varied greatly and were 1.07–35.11 m yr−1, 28.95–562.46 m2 yr−1 and 56.82–6626.37 m3 yr−1, respectively, with the average of 9.07 m yr−1, 156.92 m2 yr−1 and 1503.02 m3 yr−1, respectively. The change in headcut migration rate was significantly affected by root density, soil properties and drainage area, of which soil texture, OMC, soil aggregate structure, and the drainage area were the critical factors influencing headcut migration in the Mollisols region of northeast China.
【 授权许可】
Unknown