Winder Lab

Konrad Karlsson and Monika Winder attended the ASLO conference and presented their research.

Konrad presented results from this project on the adaptation potential of Baltic Sea copepod species to climate change. The study shows that warm adapted populations could be better prepared for future elevated temperatures, but food quality and lower salinity could hamper their relative benefits.

Monika presented research on phytoplankton diversity across the land-sea interface and it’s importance for secondary production. This study combines long-term phytoplankton observations and food quality of phytoplankton taxa, showing that the type of food quality produced in estuarine-coastal ecosystems is likely another factor contributing to their high productivity.

Photo: left: Konrad Karlsson, right: Konrad Karlsson, Andrea Caputo, Monika Winder

This synthesis article is based on a collaborative effort highlighting the importance of benthic-pelagic coupling under changing environmental conditions using the Baltic Sea as a case study.

We illustrate the varied nature of physical and biological benthic–pelagic coupling processes and their potential sensitivity to three anthropogenic pressures – climate change,nutrient loading, and fishing – and summarize current knowledge on the exchange of inorganic nutrients and organic material between habitats. We emphasize how improved empirical and experimental understanding of benthic–pelagic coupling processes and their variability are necessary to inform models that can quantify the feedbacks among processes and ecosystem responses to a changing world, and give recommendation for future research.

Griffiths, J. R., Kadin, M., Nascimento, F. J. A., Tamelander, T., Törnroos, A., Bonaglia, S., Bonsdorff, E., Brüchert, V., Gårdmark, A., Järnström, M., Kotta, J., Lindegren, M., Nordström, M. C., Norkko, A., Olsson, J., Weigel, B., Žydelis, R., Blenckner, T., Niiranen, S. and Winder, M. (2017) The importance of benthic–pelagic coupling for marine ecosystem functioning in a changing world. Glob Change Biol. doi:10.1111/gcb.13642

We have an open PhD position in our group with focus on benthic-pelagic coupling.

Closing date: 20 September 2016

This position will be associated with the FORMAS project ‘Responses of pelagic-benthic coupling to environmental change in the Baltic Sea’. The goal of this project is to disentangle how shifts in pelagic and benthic species composition can affect the flux of organic matter and nutritional quality of settling material. The student will study relationships between planktonic and benthic dynamics using monitoring data, reciprocal fluxes of particulate organic matter and potentially experiments using experiments, and use this information to project functional species traits under future climate and nutrient scenarios. The project involves statistical analysis, experiments and modelling to assess effects of human pressure on benthic-pelagic coupling processes.

Please visit the University website for more information at:

http://www.su.se/english/about/vacancies/vacancies-new-list

… in an interesting discussion with the opponent Prof. Kevin Flynn and the evaluation committee.

Jens defended his thesis entitled ‘Species interactions and energy transfer in aquatic food webs’ with the opponent Prof. Michael Brett and the evaluation committee Jan 26th. Congratulations!

A continuous challenge in ecology is to estimate and predict trophic structures in complex food webs. Knowledge on trophic interactions is crucial for our understanding of energy pathways, predations and feeding patterns in ecosystems.

Analysis of amino acid  stable nitrogen isotope ratios is a relatively new and powerful technique for estimating trophic position of organisms.  One of the primary advantages of this method, compared to common bulk stable isotopes, is that the stable nitrogen isotope ratios of some amino acids measured in a consumer’s tissue are very similar to the primary producers at the base of the food web, while the stable nitrogen isotope ratios of other amino acids increase with each trophic position.

In this paper we present the first meta-analysis of stable nitrogen isotope ratios of amino acids from measurements of 359 marine species covering four trophic levels for predicting species trophic position. This study clarifies the advantages and limitations of using stable nitrogen isotope ratios of amino acids as a tool in trophic ecology and provides a guideline for future application of this technique in food web studies.

The full study can be found here:

Nielsen, J. M., B. N. Popp, and M. Winder. 2015. Meta‐analysis of amino acid stable nitrogen isotope ratios for estimating trophic position in marine organisms. Oecologia: DOI:10.1007/s00442-015-3305-7.

Here we investigate the nutritional value of resources for pelagic fishes of the upper San Francisco Estuary to understand whether recent fish declines are liked to shifts in zooplankton nutritional conditions due to the establishment of invasive species. Using stable isotopes, elemental stoichiometry and fatty acid analyses for all dominant invasive and native zooplankton taxa and seston, we characterized the plankton community structure in the estuary and demonstrated taxon-specific differences in their nutritional value. We found temporal increase in the community-level DHA, n3 to n6 fatty acid ratio, decrease in the community-level EPA and PUFA in the brackish water region, but no change in the bulk PUFA proportions in the freshwater region of the estuary. These changes were caused mainly by declines of native cladocerans that are rich in EPA and by an increase in the dominance of invasive taxa with high DHA concentrations, similar to that of native taxa. Although we showed temporal shifts in individual fatty acid classes, the proportion of the essential fatty acids remained relatively high, suggesting that nutritional prey availability for fish remained unchanged with the shift in species composition. The study in published in:

We are excited to announce that we will be holding a course on Science Communication Training for PhD students this coming spring 23-27 March 2015.

A brief description of the course is below and you can find more information on the course website http://scicommstockholmuni.wordpress.com/

The goal of this course is to provide basic training in communicating science to non-scientific audiences. We will explore motivations and goals of science communication. You will develop a communication portfolio consisting of a message box, elevator pitch, public speed talk, and press release focused on your research. While developing your portfolio, you will learn techniques for successful communication including how to avoid jargon, developing analogies, using narrative techniques, and public speaking skills. In addition, we will engage with communication specialists, members of the media, and scientist communicators to explore the challenges and expectations from all participants in the science communication process. Students from all scientific disciplines are welcome to apply.

After our group lunch meeting in the Botanical Garden to wish Aaron good luck.

We are setting up a mescosm experiment  in the Baltic Sea to study how climate change affects food web interactions and feedback loops: