Group hike

On the 24th of June 2019 the Allan Lab made an excursion to the mountains in the Kandertal region.
We started in the morning from Bern by train and after changing to the “postbus” in Reichenbach we took the “chairlift” up to Ramslauenen. We hiked around the top and after a picnic followed a path back to Kiental. Despite the heat and the steep slopes, we enjoyed the blue sky, the fantastic panorama, the alpine flora and each other’s company.
We also used this opportunity to learn something about the vegetation – Debi showed us many species and explained to us their special characteristics and habitat.

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First results of PaNDiv on preprint

IMG_20171003_140655623After 840 litter bags sewed, 2.5 months of decomposition, 4 years of experiment running and more than a 100 helpers helping, we are happy to announce that we submitted last week the first results of the PaNDiv Experiment. This paper looks at the response of decomposition to direct and indirect effects of nitrogen enrichment, with a fancy structural equation model testing the relative importance of litter quality and soil biotic and abiotic conditions.

It highlights the importance of a plant community functional shift under nitrogen enrichment. And for those that can’t wait until the paper gets accepted, here is the submitted draft on bioRxiv:

Decomposition disentangled, Pichon et al. 2019 (preprint)

Final results of the structural equation model, showing effects of nitrogen enrichment, plant species richness and plant functional composition on decomposition. Dashed arrows show negative, full arrows positive path coefficients. The arrow size is proportional to the path coefficient. Double-headed grey arrows show covariances.

 

BES Annual Meeting 2018

The best thing about Christmas is the BES Annual Meeting. Some of the lab members – Seraina, Eric and Noémie – attended the venue in Birmingham and had the chance to follow an extraordinary selection of talks and posters. Among others, we saw a great session about long-term experiments, what has been done and what is to do next (Andy Hector, Alexandra Weigelt and others). To the question “are you also part of a long term experiment?”, we are now answering: “we just started one”. We also saw presentations about phylogenetic and functional traits linked to multifunctionality (Y. Le Bagousse-Pinguet), upscaling BEF experiments results to landscape diversity (G. Le Provost), a great citizen science project looking at herbivory drivers on oaks (E. Valdés-Correcher) and my personal favourite, tracing C and N flows in grassland plants and soil food webs (M. Chomel).

A whole wall was covered in drawings due to the Journal of Applied Ecology brilliant suggestion to “draw your study organism” (see Seraina’s work of art, #PaNDiv), and we could even play cards with the Catastrophic game supporting systems thinking (P. Holland).

Let’s not forget the great poster about sick plants in grassland communities (S. Cappelli) and a presentation disentangling nitrogen direct and indirect effects on decomposition (N. Pichon).

What a nice and motivating end to 2018 and look forward to 2019!

NP & SC

 

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Study organism drawings

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The vegetative traits are for sure right

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Noémie and the decomposition

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Another highlight of the conference: Phil Grime in front of his poster

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Seraina and sick plants

Fieldwork season wrap up

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The sheep are now back next to the PaNDiv field site, which means two things: winter is coming, and after a season outside the fieldwork is over!

Maintaining the experiment has already kept us quite busy over the last months: weeding three times the whole field to always have the same diversity in the plots, spraying fungicide for the pathogen exclusion treatment and fertilizing to study the effects of Nitrogen addition.

On top of that, we harvested this year again a lot of data. For all our species, we quantified fungal pathogen infection, looked at herbivory damage and measured classic functional traits (height, SLA, LDMC, etc). We assessed the percentage cover of all plant species growing on the field, and collected over 3000 biomass samples and 30 000 insects. This year we had a closer look at the belowground compartment, measuring soil respiration regularly and collecting more than 1000 soil samples.

We also welcomed researchers from other universities to collaborate on the PaNDiv project. Rodrigo Granjel (1), PhD student from Sevilla, Spain collected data to study coexistence mechanisms. Bjarke Madsen and Urs Treier (2) from Aarhus, Denmark, flew their drones over the field, to link ground measurements with remote sensing data.

In our greenhouses facility, we grew the 20 PaNDiv species and the most common weeds invading the plots with an N addition treatment, to get an array of functional traits in controlled conditions. We also used this opportunity to explore the variability and the response of morphological traits, for instance related to vegetative propagation, together with Mathieu Millan, a researcher in plant architecture from Montpellier, France

We couldn’t do that much without a dedicated team of PhD, Master students and technicians, and all our hard working field helpers. More than 50 different people came to work with us between April and November, thank you!

Now it’s time to process all these samples, analyse the data … and get ready for next fieldwork season!

(1) http://www.oscargodoy.com/
(2) https://twitter.com/UAS4Ecology

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March, a cold start of the fieldwork season

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In June the plants have grown big

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Spraying fungicide to study the effects of pathogen removal

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July, second weeding of the whole field

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Biomass cutting (photo Beatrice Schranz)

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Collecting insects with suction sampling

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Graphosoma italicum, one of the many insects found on the field (photo Tosca Mannall)

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Autumn soil sampling

ESP Europe Conference 2018

Some people from our Lab – Maria, Noëlle and Abiel – as well as Markus Fischer have been to the Ecosystem Services Partnership (ESP) Conference 2018 in San Sebastian, Spain.

We enjoyed a week of great talks and keynotes but also other “services” like local customs showcased during the conference, all kinds of pintxos, as well as the beautiful sights of the city and surrounding landscapes and see.

Our session T2b Linking land management and biodiversity change to ecosystem services organized by Maria was met with great interest by participants. We had lively discussion on how we can bridge from ecosystem functioning to ecosystem services to policy and how we should not forget that they are underpinned by biodiversity. We also agreed that a more mechanistic understanding would further the usefulness of the ecosystem service concept.

Twitter: #esp18eu

ESP session

Maria presenting her talk

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Basque stone-lifting before the poster session

San Sebastian sea

Noëlle and Maria on the beach

PaNDiv-ing in China

I recently arrived in China for a two months research stay as part of my PhD in the PaNDiv project. PaNDiv is a large grassland biodiversity experiment in Bern, established in 2015. We manipulate biodiversity, functional composition, nitrogen and foliar fungal pathogens. I study the role of fungal pathogens in this grassland. Soon after I started my PhD, I found Xiang Liu and the research group of professor Shurong Zhou because of two amazing papers about fungal pathogens and nitrogen enrichment in grassland. This sounds like PaNDiv, but in China instead of Switzerland. Excitingly their results point in a similar direction as our preliminary analysis for the PaNDiv Experiment, with faster growing plant communities under nitrogen fertilization showing higher infection levels than slower growing ones. This indicates that we are on the trail of universally valid patterns (at least for grasslands) and just screams for collaboration and measurements to make our results more comparable. The Young Academic Support of the University of Bern allows me to travel to China, learn new ways of measuring fungal infection and measure plant traits related to their growth strategy to link this to fungal infection. Before I “PaNDived” into field work on the Tibetan High plateau, I stayed a few days in Shanghai, to get to know the research group. Xiang already gave me a very warm welcome (haha warm: its 35°C outside and very tropical). An update about field work in China will follow soon.
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the view from my current home

Featured

Our community ecology group at University of Bern (led by Eric Allan) works on two interlinked questions: what maintains diversity within plant communities? And what effects do changes in community diversity have on the functioning of ecosystems and the services they provide?
We try to understand the biodiversity of plant communities from several different angles and we do experiments in the field and greenhouse and use statistical modelling to test these questions in large datasets.
On our website you can find more information on the major projects we are involved in, together with updates on our activities and interests.