EESS talk on "The role of microbial diversity for soil functioning "


Event details

Date 18.04.2023
Hour 12:1513:15
Speaker Dr.Luiz Domeignoz Horta, Department of Evolutionary Biology and Environmental Studies, ETHZ
Location Online
Category Conferences - Seminars
Event Language English
Soils are the largest and most dynamic terrestrial carbon (C) pool, storing 2000 Pg of C – more than the atmosphere and biosphere combined. However, agriculture has caused the loss of approximately 60 Pg soil C since the beginning of industrial period. As agroecosystems represent over 40% of the earth's surface today, they must be part of the solution put in action to mitigate climate change. The utility of management practices to maximize soil carbon storage – is currently limited by a poor understanding of how plants which input carbon to soil, and the microbes which determine its fate there interact with one-another. I am combining laboratory experiments and field experiments to unravel the mechanisms of soil organic matter (SOM) formation and persistence in soils. While my laboratory experiments shed light into how complex communities generate more persistent SOM and the distinct roles of fungi and bacteria on this process, studying a novel plant diversity farming experiment we show that plant diversity mediated the associations between the microorganisms enhancing the community carbon use efficiency and potential soil carbon retention. Altogether these results will help us better understand the mechanisms by which soil microbial diversity is important for the formation of persistent soil organic matter and disentangle how farmers can implement more sustainable practices and help retain carbon into soils.

Short biography:
I am a microbial ecologist interested in when and where “who’s there” matters for ecosystem functioning. I combine laboratory experiments with large-scale field manipulations, biogeochemical measurements and multi-omics approaches to unravel the drivers of soil functioning. One of the key themes of my research is how diversity drives ecosystem function. My interest in this theme was largely instigated during my PhD where I evaluated the effect of agricultural practices on nitrogen cycling related bacteria and their relationship with N2O emissions. I showed that the diversity of soil bacterial N2O-reducers is negatively related to the proportion of N2O emitted from agricultural soils. This made me wonder whether diversity may also impact more general community properties such as carbon use efficiency. So, for my first postdoc I developed a model soil microcosm system to evaluate how microbial diversity affects microbial carbon use efficiency. I showed that microbial diversity drives the efficiency with which microbes utilize carbon in soil, and that abiotic factors (i.e. moisture) can modulate this relationship. On my current project I am evaluating the relationships and feedback(s) between plant diversity and soil microorganisms. I am investigating how plant diversity influences microbial interactions and carbon use efficiency in the rhizosphere. I am doing this by linking various disciplines including plant functional ecology, microbiology, stable isotopes and soil biogeochemistry to shed light into how farmers can implement more sustainable practices.

Practical information

  • General public
  • Free
  • This event is internal


  • EESS - IIE


  • Prof. Meret Aeppli, SOIL


soil carbon cycling nitrogen cycling microbial diversity ecosystem functioning plant diversity agriculture sustainability