文献类型：期刊文献

英文题名：How does biochar affect surface-underground soil and water loss on soil-mantled hillslopes in karst regions?- Evidence from the soil structure

作者：Zi, Ruyi Yin, Xiaoai Fang, Fayong Chen, Tingsheng Han, Zhen Hou, Rui Zhao, Longshan

第一作者：Zi, Ruyi

通信作者：Zhao, LS[1]

机构：[1]Guizhou Univ, Coll Forestry, Guiyang 550025, Peoples R China;[2]Guizhou Univ, Key Lab Karst Georesources & Environm, Minist Educ, Guiyang 500025, Peoples R China;[3]Guizhou Inst Technol, Sch Civil Engn, Guiyang 550001, Peoples R China

第一机构：Guizhou Univ, Coll Forestry, Guiyang 550025, Peoples R China

通信机构：corresponding author), Guizhou Univ, Coll Forestry, Guiyang 550025, Peoples R China.

年份：2025

卷号：662

外文期刊名：JOURNAL OF HYDROLOGY

收录：;EI(收录号：20253419044975);WOS:【SCI-EXPANDED(收录号:WOS:001565880200004)】；

基金：This work was supported by the National Natural Science Foundation of China (42367045), the Guizhou Provincial High-level Innovative Talents Project (QKHPTRC-GCC[2023]015), and the Guizhou Provincial Key Technology R&D Program (QKHZC[2022]YB202; QKHPT-KXJZ [2024]020).

语种：英文

外文关键词：Biochar; Soil conditioner; Soil structure; Soil and water loss; X-ray computed tomography; Karst region; Biochar; Soil conditioner; Soil structure; Soil and water loss; X-ray computed tomography; Karst region

摘要：The application of biochar to soil has demonstrated the potential for improving soil structures and mitigating soil erosion. However, it is not yet clear how biochar regulates soil and water loss by altering the soil structure, especially in karst areas with dual-layer structures. To address this knowledge gap, a 3-year field monitoring experiment was carried out in a karst region of Southwest China to evaluate the impacts of biochar application rates (0 wt%, 1.36 wt%, and 2.72 wt%, referred to as the CK, T1, and T2 treatments, respectively, with three replicates for each treatment) on the runoff and soil loss dynamics. High-resolution X-ray computed tomography (CT) was employed to quantify the alterations in soil pore structures across treatments. The findings indicated that biochar amendment notably increased the number of soil aggregates, porosity, pore connectivity, and tortuosity while reducing the pore channel length (P < 0.05). These improvements exhibited dose-dependent responses to the different biochar application rates. Compared with the CK treatment, biochar application reduced subsurface runoff and underground fissure flow by 22.51 %-31.87 % and decreased soil loss from subsurface and underground fissures by 69.92 %-86.48 % (P < 0.05). Unexpectedly, the surface runoff and surface soil loss increased by 12.69 %-14.77 % and 33.80 %-43.99 %, respectively (P > 0.05). This occurred because the altered soil structure caused by biochar affects rainfall infiltration and water transportation efficiency, leading to increased surface runoff. On the other hand, biochar disrupted native soil aggregates, reducing their stability and increasing the susceptibility to surface soil detachment. Additionally, surface soil and water loss were positively correlated with soil pore connectivity and tortuosity, and negatively correlated with pore channel length and total pore surface area. Conversely, the soil and water loss in subsurface and underground fissures exhibited opposite trends (P < 0.05). These relationships can be described by linear functions (R2 = 0.31-0.92, P < 0.05). Our results implied that using biochar in soils poses a risk of increased surface erosion on soil-mantled hillslopes in karst regions. Consequently, integrating biochar with complementary erosion control strategies is recommended to achieve dual mitigation of surface and underground soil and water loss in karst landscapes.