Exploring the relationship between soil mesofauna, soil structure and N2O emissions.
We analysed soil structural parameters using X-ray tomography to explain the role of soil mesofauna in nitrous oxide emissions (N2O) from agricultural soil. The experiment was set up in the Soil Physics Laboratory:
Potworms, fungivorous mites and predatory mites were introduced into the microcosms (and all of their combinations):
N2O and also CO2 fluxes were measured with a static closed chamber
technique, type 1302 multi gas monitor (Brüel & Kjaer, Naerum, Denmark).
Potworms accelerated peak N2O emissions, but neither fungivorous mites nor predatory mites nor their interactions had a significant effect on N2O
Soil scanning (X-ray tomography) was performed using the v[tome]x m (Phoenix X-ray/General Electric). Potworms clearly affected the soil structure by increasing the volumetric air content and altering the pore size distribution. In addition, visual observations indicate a more continuous pore network in the soil microcosms when potworms are present:
In conclusion: soil structure is an important pathway driving faunal-induced N2O emissions, and soil ecosystem engineers such as potworms disproportionally affect N2O emissions as compared to other soil fauna.
Porre RJ, Van Groenigen JW, De Deyn GB, De Goede RGM, Lubbers IM (2016) Exploring the relationship between soil mesofauna, soil structure and N2O emissions. Soil Biology & Biochemistry 96:55-64.