Global Atlas of Methane Metabolism Marker Genes in Soil

Methane, a greenhouse gas, plays a pivotal role in the
global carbon
cycle, influencing the Earth’s climate. Only a limited number
of microorganisms control the flux of biologically produced methane
in nature, including methane-oxidizing bacteria, anaerobic methanotrophic
archaea, and methanogenic archaea. Although previous studies have
revealed the spatial and temporal distribution characteristics of
methane-metabolizing microorganisms in local regions by using the
marker genes pmoA or mcrA, their
biogeographical patterns and environmental drivers remain largely
unknown at a global scale. Here, we used 3419 metagenomes generated
from georeferenced soil samples to examine the global patterns of
methane metabolism marker gene abundances in soil, which generally
represent the global distribution of methane-metabolizing microorganisms.
The resulting maps revealed notable latitudinal trends in the abundances
of methane-metabolizing microorganisms across global soils, with higher
abundances in the sub-Arctic, sub-Antarctic, and tropical rainforest
regions than in temperate regions. The variations in global abundances
of methane-metabolizing microorganisms were primarily governed by
vegetation cover. Our high-resolution global maps of methane-metabolizing
microorganisms will provide valuable information for the prediction
of biogenic methane emissions under current and future climate scenarios.