干旱区生态环境知识资源中心(Arid): Migration of Dissolved Organic Matter in the Epikarst Fissured Soil of South China Karst

Arid

DOI	10.3390/land12040887
	Migration of Dissolved Organic Matter in the Epikarst Fissured Soil of South China Karst
	Cheng, Kun; Liu, Ziqi; Xiong, Kangning; He, Qiufang; Li, Yuan; Cai, Lulu; Chen, Yi
通讯作者	Xiong, KN
来源期刊	LAND
EISSN	2073-445X
出版年	2023
卷号	12 期号:4
英文摘要	The efficient reactivity and mobility of dissolved organic matter (DOM) affect biogeochemical processes. As important components that link aboveground and belowground vertical systems under the binary 3D structure of karst, fissures provide soil-water-nutrient leakage channels and storage spaces. However, reports on DOM properties and drivers in fissured soil are extremely rare. This study characterizes DOM in the fissured soil of different vegetation types under medium-intensity rocky desertification conditions. Soil samples were characterized via ultraviolet (UV)-visible absorption spectroscopy and fluorescence excitation-emission matrix-parallel factor analysis. Five fluorescent fractions were identified. The controlling factors for the optical properties of soil DOM were determined via the redundancy analysis method. Results showed the following: (1) Dissolved organic C/soil organic C < 4.68 + 0.49 parts per thousand, specific UV absorbance (SUVA)(254) and SUVA(260) exhibited low overall performance with the vast majority of the humification index (HIX) < 4, most of the fluorescence index (FI) >= 1.7, most of the biological index (BIX) in 0.6 < BIX < 1 and 31.67-41.67% of protein-like fractions. These data indicate that cleaved soil, except for topsoil, has low DOM content, weak aromaticity, and low humification; (2) Rainfall intensity, aperture, and near-surface vegetation type are the major causes of DOM transport and loss; and (3) Most DOM losses are likely to be protein-like and enhance the loss of soil P. In summary, environmental factors and the characteristics of fissures determine DOM content and migration, particularly rainfall intensity and vegetation type. The loss of lighter DOM components will be greater in an area with high karst desertification grade, strong fissure development, weaker soil aromaticity, and lower humification. These results provide a clearer basis for optimizing the fissure nutrient element migration scheme in karst areas.
英文关键词	DOM UV fluorescence migration karst fissure
类型	Article
语种	英语
开放获取类型	gold
收录类别	SSCI
WOS记录号	WOS:000977311300001
WOS关键词	ROCKY DESERTIFICATION REGIONS ; FLUORESCENCE SPECTROSCOPY ; VEGETATION RESTORATION ; CHEMICAL-COMPOSITION ; SIZE DISTRIBUTION ; LOESS PLATEAU ; LAND-USE ; CARBON ; DOM ; EROSION
WOS类目	Environmental Studies
WOS研究方向	Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/397649
推荐引用方式 GB/T 7714	Cheng, Kun,Liu, Ziqi,Xiong, Kangning,et al. Migration of Dissolved Organic Matter in the Epikarst Fissured Soil of South China Karst[J],2023,12(4).
APA	Cheng, Kun.,Liu, Ziqi.,Xiong, Kangning.,He, Qiufang.,Li, Yuan.,...&Chen, Yi.(2023).Migration of Dissolved Organic Matter in the Epikarst Fissured Soil of South China Karst.LAND,12(4).
MLA	Cheng, Kun,et al."Migration of Dissolved Organic Matter in the Epikarst Fissured Soil of South China Karst".LAND 12.4(2023).