Salinity-dependent potential soil fungal decomposers under straw amendment

Lu Zhang; Chong Tang; Jingsong Yang; Rongjiang Yao; Xiangping Wang; Wenping Xie; An-Hui Ge

doi:10.1016/j.scitotenv.2023.164569

Salinity-dependent potential soil fungal decomposers under straw amendment

Sci Total Environ. 2023 Sep 15:891:164569. doi: 10.1016/j.scitotenv.2023.164569. Epub 2023 Jun 2.

Authors

Lu Zhang¹, Chong Tang², Jingsong Yang³, Rongjiang Yao¹, Xiangping Wang¹, Wenping Xie¹, An-Hui Ge⁴

Affiliations

¹ State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
² State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
³ State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. Electronic address: jsyang@issas.ac.cn.
⁴ National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.

PMID: 37269992
DOI: 10.1016/j.scitotenv.2023.164569

Abstract

Soil salinization is a severe environmental problem that restricts plant productivity and ecosystem functioning. Straw amendment could increase the fertility of saline soils by improving microbial activity and carbon sequestration, however, the adaptation and ecological preference of potential fungal decomposers after straw addition under varied soil salinities remains elusive. Here, a soil microcosm study was conducted by incorporating wheat and maize straws into soils with a range of salinities, respectively. We showed that the amendment of straws increased MBC, SOC, DOC and NH₄⁺-N contents by 75.0 %, 17.2 %, 88.3 % and 230.9 %, respectively, but decreased NO₃^--N content by 79.0 %, irrespective of soil salinity, with intensified connections among these parameters after straw addition. Although soil salinity had a more profound effect on both fungal α- and β-diversity, straw amendment also significantly reduced fungal Shannon diversity and changed community composition, especially for severe saline soil. Complexity of the fungal co-occurrence network was specifically strengthened after straw addition, with average degree increasing from 11.9 in the control to 22.0 and 22.7 in wheat and maize straw treatments, respectively. Intriguingly, there was very little overlap among the straw-enriched ASVs (Amplicon Sequence Variants) in each saline soil, indicating the soil-specific involvement of potential fungal decomposers. Particularly, fungal species belonging to Cephalotrichum and unclassified Sordariales were the most responsive to straw addition in severe saline soil, whereas light saline soil supported the enrichment of Coprinus and Schizothecium species after straw addition. Together, our study provides a new insight on the common and specific responses of soil chemical and biological characteristics at different salinity levels under straw management, which will help guide precise microbial-based strategies to boost straw decomposition in future agricultural practice and environmental management of saline-alkali lands.

Keywords: Decomposers; Fungi; Saline soils; Straw-return.

MeSH terms

Agriculture
Ecosystem*
Salinity
Soil Microbiology
Soil* / chemistry
Triticum
Zea mays / chemistry

Substances

Soil