EGU22-2206, updated on 10 Jan 2024
https://doi.org/10.5194/egusphere-egu22-2206
EGU General Assembly 2022
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Conservation tillage practices facilitate soil organic carbon sequestration and aggregate stability via fungal abundance and necromass

Orracha Sae-Tun1, Gernot Bodner2, Christoph Rosinger1,2, Thomas Weninger3, Sophie Zechmeister-Boltenstern1, Axel Mentler1, and Katharina Keiblinger1
Orracha Sae-Tun et al.
  • 1Institute of Soil Research, University of Natural Resources and Life Sciences Vienna, BOKU, Peter-Jordan-Straße, 1190 Vienna, Austria
  • 2Institute of Agronomy, University of Natural Resources and Life Sciences Vienna, BOKU, Konrad-Lorenz-Straße 20, 3430 Tulln, Austria
  • 3Federal Agency of Water Management (BAW), Department for Watershed hydrology and erosion, Pollnbergstraße 1, 3252 Petzenkirchen, Austria

Conservation tillage has been widely applied to improve soil health, sustain crop production, and promote carbon (C) sequestration in soil. Positive effects often depend on the degree of tillage intensity and time of adoption. This study was thus aimed to determine temporal changes of selected soil health indicators under different tillage intensities in a long-term tillage trial.

Accordingly, bulk and rhizosphere soil samples were taken after 8 and 13 years of adoption from topsoil under four different tillage systems ranging from conventional (high intensity), reduced, minimum, to no-tillage (low intensity).  Aggregate stability and soil fungal indicators (ergosterol and glomalin-related soil protein) were analysed. Soil organic carbon stocks were assessed at 10 and 13 years of adoption. To determine long-term effect of tillage on soil microbial necromass accumulation, amino sugars were measured after 13 years of adoption.

Aggregate stability and soil fungal indicators increased with lower tillage intensity for both sampling time points. Conservation tillage practices promoted the accumulation of soil organic carbon and microbial necromass. Interestingly, among conservation tillage practices, the soil fungal indicators showed highest values for reduced and minimum tillage compared to no-tillage at 13 years of adoption. This suggests that fungal growth could potentially benefit from slight soil disturbance in the long-term. Therefore, reduction of tillage intensity evidently improved soil health by promoting soil carbon sequestration and aggregate stability via fungal growth as well as soil microbial necromass accumulation.

Conventional tillage is most detrimental to soil health indicators, while reduced tillage seem to promote soil biological processes via gentle mixing of soil substrate. Instead, no-tillage is most beneficial to aggregate stability but not for fungal indicators.  

How to cite: Sae-Tun, O., Bodner, G., Rosinger, C., Weninger, T., Zechmeister-Boltenstern, S., Mentler, A., and Keiblinger, K.: Conservation tillage practices facilitate soil organic carbon sequestration and aggregate stability via fungal abundance and necromass, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-2206, https://doi.org/10.5194/egusphere-egu22-2206, 2022.