Forums | HES 健康与环境科学

01 March 2024, 1:10 PM

Speaker: Yujia Cai

Date: 2024-03-07

Time: 13:00-13:30 

Room: ES354

Online link: https://meeting.tencent.com/dm/v169BGHYrPM6

Meeting ID: 668-4466-7997

Title: Millimeter-scale partitioning of nitrogen-cycling microbial activity across the soil-water interface and implications for N₂O emissions

Abstract:

Soil-water interfaces (SWI) are ubiquitous in wetlands and important zones of biogeochemical processes. However, the spatial organization of microbial activity involved in nitrogen (N) cycling and N₂O emissions remains poorly characterized. Here, we examined the distribution of N-cycling communities across the SWI at the millimeter (mm)-scale by characterizing their distribution and transcriptional activity coupled with process rate measurements. The effect of daylight was also evaluated to imitate real environmental change. Active N transformation dominated the first 10 mm layer of flooded soils. Notably, nosZ N₂O-reducers were most active at the surface while N₂O concentrations were greatest in deeper layers, indicating that the SWI can serve as a filter for the up-diffusing N₂O. Differences were observed in the spatial distribution of N functional genes and transcript abundance, and as a response to light, indicating niche differentiation particularly in functional-equivalent cohorts. These findings demonstrate a long-neglected scale at which the N-cycling community activity can vary across the SWI and its role in controlling the flux of N₂O emissions to the atmosphere.