Temporal and spatial dynamics of microbial communities and greenhouse gas flux responses to experimental flooding in riparian forest soils

作者：Kristel Reiss, Ülo Mander, Maarja Öpik, Siim‐Kaarel Sepp, Kärt Kanger, Thomas Schindler, Kaido Soosaar, Mari Pihlatie, Klaus Butterbach‐Bahl, Anuliina Putkinen, Ülo Niinemets, Mikk Espenberg · 发表于：FEMS Microbiology Ecology · 年份：2025 · DOI：10.1093/femsec/fiaf109 · 被引用次数：4 · 研究领域：Microbial Community Ecology and Physiology、Forest Ecology and Biodiversity Studies、Mycorrhizal Fungi and Plant Interactions

Extreme rainfall and flooding are expected to increase in Northern subboreal habitats, altering soil hydrology and impacting greenhouse gas (GHG) fluxes by shifting redox potential and microbial communities as soils transition from aerobic to anaerobic conditions. This study examined the effects of a 2-week growing-season flash flood on bacterial, archaeal, and fungal communities and microbial processes driving CH4 and N2O fluxes in riparian alder (Alnus incana) forests. Flooding reduced soil nitrate accumulation as determined by quantitative polymerase chain reaction and promoted dinitrogen-fixing, nifH gene-carrying bacteria like Geomonas. Sequencing data showed that anaerobic bacteria (Oleiharenicola, Pelotalea) increased during the flood, while N2O emissions declined, indicating a shift towards complete denitrification to N2. However, drier patches within the flooded area emitted N2O, suggesting nitrification or incomplete denitrification. A diverse arbuscular mycorrhizal community was detected, including genera Acaulospora, Archaeospora, Claroideoglomus, Diversispora, and Paraglomus. Flooding increased the abundance of the fungal genera Naucoria, Russula, and Tomentella and the family Thelephoraceae, which symbiotically support alder trees in nitrogen uptake and carbon sequestration. Microtopographic differences of 0.3-0.7 m created spatial variability in GHG emissions during flooding, with some waterlogged areas emitting CH4, while others enhanced CH4 oxidation (determi...