A Global Database of Soil Methane Uptake (SMUD)

Abstract

Soil methane uptake (SMU), an important biological sink for atmospheric methane (CH 4 ) in terrestrial ecosystems, represents an important component of the global CH 4 budget. Although field SMU observations have been conducted since the 1980s, they have not yet been systematically compiled into a unified and openly available database. Here, we present the global Soil Methane Uptake Database (SMUD), which includes 2427 site-level records from 920 peer-reviewed publications spanning 1986 to 2025. SMUD contains SMU measurements at multiple temporal scales, including daily ( n =1425), monthly ( n =2001), seasonal ( n =1720), and annual ( n =1098), together with associated soil moisture and soil temperature data at daily and monthly scales where available. The collected datasets cover all major climatic zones and ecosystem types and reveal pronounced spatial and temporal variability in SMU. Our analyses show that seasonal- and biome-specific patterns are important for understanding intra-annual variability in SMU. In particular, quantitative classification showed that the relationships of SMU with soil temperature and moisture differed among biomes, resulting in four response types: temperature-dominated, moisture-dominated, jointly regulated by temperature and moisture, and no clear dominant control. Overall, SMUD provides a comprehensive basis for characterizing global SMU patterns, investigating underlying mechanisms, and improving estimates of the global SMU budget. The database, associated data, and code for reproducing the results are available at https://doi.org/10.5281/zenodo.20735332 (Jiang et al., 2026). We aim to maintain SMUD as a collaborative, community-supported, and regularly updated resource for the research community.