Earthworms do not increase greenhouse gas emissions (CO2 and N2O) in an ecotron experiment simulating a three-crop rotation system

• Published in: Scientific reports Vol. 13; no. 1; p. 21920
• Main Authors: Forey, Oswaldo, Sauze, Joana, Piel, Clément, Gritti, Emmanuel S., Devidal, Sébastien, Faez, Abdelaziz, Ravel, Olivier, Nahmani, Johanne, Rouch, Laly, Blouin, Manuel, Pérès, Guénola, Capowiez, Yvan, Roy, Jacques, Milcu, Alexandru
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 08-12-2023; Nature Publishing Group; Nature Portfolio
• Subjects: 631/158/2165; 631/158/2445; 631/158/2456; Agricultural practices; Agricultural sciences; Carbon dioxide; Carbon dioxide emissions; Crop rotation; Ecology, environment; Ecosystems; Emissions; Evapotranspiration; Farm buildings; Greenhouse gases; Humanities and Social Sciences; Life Sciences; Lysimeters; multidisciplinary; Nitrous oxide; Oligochaeta; Science; Science (multidisciplinary); Soil depth; Soil gases; Soil study; Water use; Water use efficiency; Worms; soil fauna; carbon dioxide; ecosystem fluxes; controlled environment; nitrous oxide; anecic; endogeic; Lumbricidae
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-023-48765-3

Earthworms are known to stimulate soil greenhouse gas (GHG) emissions, but the majority of previous studies have used simplified model systems or lacked continuous high-frequency measurements. To address this, we conducted a 2-year study using large lysimeters (5 m
2
area and 1.5 m soil depth) in an ecotron facility, continuously measuring ecosystem-level CO
2
, N
2
O, and H
2
O fluxes. We investigated the impact of endogeic and anecic earthworms on GHG emissions and ecosystem water use efficiency (WUE) in a simulated agricultural setting. Although we observed transient stimulations of carbon fluxes in the presence of earthworms, cumulative fluxes over the study indicated no significant increase in CO
2
emissions. Endogeic earthworms reduced N
2
O emissions during the wheat culture (− 44.6%), but this effect was not sustained throughout the experiment. No consistent effects on ecosystem evapotranspiration or WUE were found. Our study suggests that earthworms do not significantly contribute to GHG emissions over a two-year period in experimental conditions that mimic an agricultural setting. These findings highlight the need for realistic experiments and continuous GHG measurements.