1.Key Laboratory of Forest Ecology and Conservation in Guangxi University;2.Key Laboratory of Agro-ecological Process in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences
Central Government Guides the Development of Local Science and Technology Project, China (Guike. ZY21195016); Guangxi Key Research and Development Project (AB22035058); National Natural Science Foundation of China (42077077).
This study aims to investigate the impact of soil physicochemical properties and plant root structure on the soil infiltration characteristics of dolomite and sand shale developed soils within karst areas. Focused on the typical karst peaks and depressions sub-watersheds in Huanjiang County, soil infiltration experiments were conducted using a disc infiltrometer (DJ-WS) at four pressure heads (0, -3, -6, and -9 cm). Simultaneously, a digital scanner was employed to determine root structure indexes, aiming to analyze the disparities in soil infiltration performance developed by these lithologies under different land uses and to identify the primary controlling factors influencing soil infiltration. The results revealed the following: 1) The stable soil infiltration rate consistently increased with the elevation of pressure head, wherein dolomite showcased superior water-conducting capacity within its larger pore spaces as compared to sand shale; 2) The root structure indicators in sand shale soil significantly surpassed those observed in dolomite; 3) The water-conducting rate of dolomite soil displayed significant or highly significant positive correlations with organic matter content, total porosity, root length density, and root bulk density. The water conductivity of sand shale soil exhibited noteworthy or highly noteworthy positive correlations with organic matter content and total porosity. Moreover, it displayed significant positive correlations with macroporous hydraulic conductivity and root structure indexes, while indicating a notable negative correlation with bulk density. Through stepwise regression analysis, it was elucidated that the infiltration of dolomite-developed soil was predominantly regulated by root length density and root bulk density. In contrast, the infiltration of sand shale-developed soil was primarily controlled by root bulk density. Consequently, root length density and root bulk density emerged as the principal controlling factors influencing soil infiltration in both dolomite and sand shale developed soils within karst areas. These results aim to offer novel insights for a more profound comprehension of water infiltration and subsurface seepage in karst regions, thereby laying a robust foundation for scientific theories and further investigations.
杨源峰,韦慧,王建羽,付智勇,杨钙仁,邓羽松. 喀斯特区两种岩性发育土壤入渗特征及其影响因素[J]. 农业现代化研究, 2023, 44(6): 1103-1116
YANG Yuan-feng, WEI Hui, WANG Jian-yu, FU Zhi-yong, YANG Gai-ren, DENG Yu-song. Infiltration characteristics and influencing factors of two types of lithological soils in karst regions[J]. Research of Agricultural Modernization, 2023, 44(6): 1103-1116