Dr.
Sofia J.
van Moorsel

Community
Ecologist

Research

Stress Responses and Adaptation in Aquatic Plant Communities

lemna In a series of glasshouse experiments, we are trying to understand how diversity and evolution interact and enable duckweed populations to persist in stressful environments. The idea is to test whether either diversity or evolution (or both) can rescue these aquatic plant communities. We are using different locally relevant stressor and duckweed populations collected in the wild. The first experiment is about to be wrapped up, hopefully we will know more soon!

Community Stability in Freshwater Mesocosms

LEAP in Mont-St-Hilaire

During my Postdoc at McGill, I studied how evolution modifies stability of aquatic (meta)communities using a Large Experimental Array of Ponds (LEAP) at McGills Gault Nature Reserve in Mont St.-Hilaire. In these ponds (107 of them!) we assembled natural lake water communities and tracked these communities over the field season 2018. We were interested in the impact of environmental stress (acidification) on ecosystem stability. We found that adaptation can help ecosytems to maintain their natural variability in a highly stressful environment. The paper was published in March 2021 at Oikos. The preprint is publicly accessible on bioRxiv here.
Please email me if you would like a pdf of the published paper.

All about LEAP and the projects carried out in 2016, 2017 and 2018 you can find here.

Community Evolution in a Grassland Biodiversity Experiment

Plantago media in Jena

We tested effects of community evolution on primary productivity in 48 different plant communities of 1, 2, 4 or 8 grassland species growin within the Jena Experiment. We found that productivity was increased if communities were assembled from plants that had previously been growing together for 8 years compared with communities assembled from plants without a common history. The observed positive effect of community evolution on productivity was independent of the presence of co-selected soil organisms but restricted to low diversity; mixtures of 8 species were not affected. We conclude that to preserve well-functioning ecosystems we need to protect interacting species in a community context. This research was published in Ecology Letters.
Link to the publication

In a second paper we wanted to find out whether community evolution (a history of co-occurrence) also increased stability and resilience in these same communities in the Jena Experiment. We therefore assessed stability during the unperturbed period and also resistance, resilience and recovery in response to a natural flooding event. We found that community evolution increased temporal stability of community funtioning (i.e. community biomass), in particular after the flood. Evolution also increased resilience and recovery, but not resistance. This research has been published in Ecology.
Link to the publication Please email me if you would like a pdf of the published papers.

Selection in Response to Plant Community Diversity

Greenhouse Experiment

Previously it was shown that differential selection in monoculture and mixed species grassland communities could lead to the rapid emergence of monoculture and mixture phenotypes (Zuppinger-Dingley et al, 2014).
I conducted a similar experiment showing that community diversity as selective environment can alter plant performance and functional traits. This research was published in Perspectives in Plant Ecology, Evolution and Systematics.
Link to the publication.

Underlying mechanisms for such rapid phenotypic responses are however still unclear. We hypothesize that in biodiversity experiments pre-adapted genotypes or epigenetic variants could be sorted out from the standing genetic or epigenetic variation. To test if biodiversity acted as a selective environment, we grew offspring from plants that were exposed for twelve years to a monocultures or mixture environment under controlled greenhouse conditions. Using epiGBS, a genotyping by sequencing approach combined with bisulphite conversion to provide integrative genetic and epigenetic data, we showed that plants with a monoculture or mixture background were genetically distinct. Our data reveals a strong correlation between genetic and epigenetic variation and suggest genetic variation as driving force of most epigenetic variation. This pattern was consistently observed across different plant species. These results suggest that, in perennial grassland species, selection of genetic variation underlies the rapid emergence of monoculture and mixture types.
Link to the publication.

For a quick overview check out the following poster (presented at the 40th New Phytologist Symposium in Vienna, Austria).
Poster: Evidence for Rapid Evolution in Grasslands (pdf)

Auf Deutsch gibt es eine Zusammenfassung hier auf der Seite der Mathematisch-naturwissenschaftlichen Fakultät der Universität Zürich.

A short English summary of the research can be found here.

Plant–Soil Interactions

AMF plant-soil feedback experiment

In a project led by my PhD colleague Dr. Terhi Hahl we assessed in greenhouse experiments whether soil community history and plant selection history interact. Specifically, we looked at interactions between plants and mutualistic soil organisms (arbuscular mycorrhizal fungi) as well as other microbes. The corresponding paper is published in Functional ecology.
Link to the publication

We were furthermore interested how both plant diversity and co-selection between plants and their associated soil microbiota can shape the microbiome of the plant rhizosphere. In a paper led by my collaborators Dr. Marc Schmid and Dr. Terhi Hahl we found that the bacterial community composition was influenced mostly by plant identity but also by soil legacy effects. The results are published in Molecular Ecology.
Link to the publication

Finally, we also assessed bacterial and fungal community composition in the soils of our experimental plots in the Jena Experiment using 16S and ITS sequencing. Soil microbial diversity was positively but weakly associated with plant diversity, with the strongest difference in microbial diversity between plant monocultures and any community of more than one plant species. Particular plant community compositions were associated with particular microbial community compositions. Soil legacy (old soil) increased soil bacterial richness and evenness more strongly than did plant community age. Plant community age (old plant communities) significantly affected the abundance of 10% of fungal OTUs. Some of the effects of soil legacy on bacterial and fungal diversity were indirect via changes in soil abiotic and biotic properties. Our findings suggest that as experimental ecosystems develop over time, plant communities associate with specific microbiomes and plant species associate with specific soil microbial species. This paper will be published in Journal of Ecology shortly. In the mean time check out the preprint!

Links