Analysis of the influence paths of land use and landscape pattern on organic matter decomposition in river ecosystems: Focusing on microbial groups

Yibo Liu; Yanping Shen; Cheng Cheng; Weilin Yuan; Hongjie Gao; Ping Guo

doi:10.1016/j.scitotenv.2022.152999

Analysis of the influence paths of land use and landscape pattern on organic matter decomposition in river ecosystems: Focusing on microbial groups

Sci Total Environ. 2022 Apr 15:817:152999. doi: 10.1016/j.scitotenv.2022.152999. Epub 2022 Jan 11.

Authors

Yibo Liu¹, Yanping Shen², Cheng Cheng², Weilin Yuan², Hongjie Gao³, Ping Guo⁴

Affiliations

¹ Key Laboratory of Groundwater Resources and Environment Ministry of Education, College of New Energy and Environment, Jilin University, Changchun 130012, PR China; Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun 130012, PR China; Chinese Research Academy of Environmental Science, Beijing 100012, PR China.
² Key Laboratory of Groundwater Resources and Environment Ministry of Education, College of New Energy and Environment, Jilin University, Changchun 130012, PR China; Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun 130012, PR China.
³ Chinese Research Academy of Environmental Science, Beijing 100012, PR China. Electronic address: gaohj@craes.org.cn.
⁴ Key Laboratory of Groundwater Resources and Environment Ministry of Education, College of New Energy and Environment, Jilin University, Changchun 130012, PR China; Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun 130012, PR China. Electronic address: guoping@jlu.edu.cn.

PMID: 35031368
DOI: 10.1016/j.scitotenv.2022.152999

Abstract

Organic matter decomposition (OMD) is one of the important river ecosystem functions. Changes in land use and landscape pattern (LULP) have a serious influence on the OMD in neighboring river ecosystems. However, there is limited information on the influence paths of LULP on organic matter decomposition in river ecosystems. In this study, cotton strip (CS) as a substitute for investigating OMD, was introduced to the delineated catchments in Luanhe River Basin in China, meanwhile combining with remote sensing interpretation, water quality analysis, microbial sequencing, and redundancy analysis (RDA) to identify the dominant LULP metrics, water quality parameters, and microbial groups controlling the OMD. Then the structural equation models (SEMs) were used to connect these dominant controlling factors to track the influence paths of LULP on OMD in river ecosystems. RDA results indicated that construction land (CON), farmland (FAR) and landscape shape index (LSI) in LULP, total nitrogen (TN), chemical oxygen demand (COD) and pH in water quality, bacterial phyla Planctomycetes and Firmicutes, as well as fungal phyla Chytridiomycota and Basidiomycota were the dominant factors controlling the OMD (quantified by tensile strength loss (TSL) and respiration (RES)). These four microbial phyla contributed significantly to OMD. SEMs further proposed three paths to explain the mechanism of LULP influencing on OMD, which were CON - TN - Firmicutes - TSL, CON - TN - Chytridiomycota - RES, and FAR - COD - Chytridiomycota - TSL. CON promoted OMD mainly through enhancing TN content in river water to increase Firmicutes and Chytridiomycota. FAR increased Chytridiomycota by decreasing COD in river water, promoting OMD. These results will deepen our understanding of the influence of LULP on river ecosystem functions and provide valuable information for policymakers and managers to carry out watershed land planning and river management in the future.

Keywords: Cotton strip; Land use and landscape pattern; Microbe; Organic matter decomposition; River ecosystems; Water quality.

MeSH terms

China
Ecosystem*
Environmental Monitoring / methods
Nitrogen / analysis
Rivers*
Water Quality

Substances

Nitrogen