Pedosphere 29(1): 102--113, 2019
ISSN 1002-0160/CN 32-1315/P
©2019 Soil Science Society of China
Published by Elsevier B.V. and Science Press
Soil Erodibility and Physicochemical Properties of Collapsing Gully Alluvial Fans in Southern China
DENG Yusong1,2, SHEN Xue3, XIA Dong1, CAI Chongfa1, DING Shuwen1, WANG Tianwei1
1Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtze River) of the Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070(China)
2Forestry College, Guangxi University, Nanning 530004(China)
3College of Economics and Management, Huazhong Agricultural University, Wuhan 430070(China)
ABSTRACT
      In southern China, collapsing gully erosion produces massive deposits of sediment on the plough layer of alluvial fan farmland, leading to reduced nutrients, increased erodibility, and even desertification. The aim of this study was to investigate soil erodibility (the factor K in the universal Soil Loss Equation, USLE) and physicochemical properties of the alluvial fans of the most severe collapsing gully erosion areas (Hubei, Jiangxi, Fujian, and Guangdong provinces) in southern China. The soils of the collapsing gully alluvial fans had a higher bulk density, but a lower total porosity, saturated water content, and silt and clay fractions than the control (CK) soils from the farmland without desertification. Soil quality gradually decreased from fan edge to fanhead. Significant decreases were found in soil pH, organic matter, cation exchange capacity, and total potassium, nitrogen, and phosphorus, as well as available nitrogen, phosphorus, and potassium, resulting in a gradual decrease in soil nutrients from the fanedge to the fanhead. Soil erodibility was greatest in the fanhead, and soil erodibility K values of the alluvial fans were 53.71%, 66.28%, 67.53%, and 71.68% greater than that in those of the CK soils of Hubei, Jiangxi, Fujian, and Guangdong, respectively, indicating a significant correlation between the soil erodibility K values and physicochemical properties, particularly sand fraction and organic matter content. The results provide new insights into the relationship between soil physicochemical properties and erodibility of alluvial fans, and suggest that improving soil structure might increase soil fertility in the collapsing gully alluvial fan farmland.
Key Words:  soil erosion,soil fertility,soil property,soil quality,soil structure
Citation: Deng Y S, Shen X, Xia D, Cai C F, Ding S W, Wang T W. 2019. Soil erodibility and physicochemical properties of collapsing gully alluvial fans in southern China. Pedosphere. 29(1):102-113.
View Full Text



Copyright © 2019 Editorial Committee of PEDOSPHERE. All rights reserved.
Address: P. O. Box 821, 71 East Beijing Road, Nanjing 210008, China    E-mail: pedosphere@issas.ac.cn
Technical support: Beijing E-Tiller Co.,Ltd.