Mads Forchhammer

Mads Forchhammer

Mads Forchhammer

Professor, Terrestrial zoology

Phone: +47 79 02 33 37
Room: B 240

Research profile

I am a quantitative population biologist who addresses ecological questions and theory with cross-disciplinary analytic models applied to observational and large-scale data sets. I have considerable experience within the field of Global Change Biology. Indeed, how climatic changes interact with the ecology and dynamics of terrestrial plants, animals and their biotic environment have been pivotal in my research and teaching over the last 15 years. Specifically, I am engaged in analyzing and modelling ecological responses of vertebrates to short- and long-term changes in intra- and inter-trophic level dynamics and to large-scale climatic variability. My work has been among the first to simultaneously incorporate climatic variation into population models as well as empirically demonstrate specific phenotypic, life history and behavioural responses to global climate change within and across trophic levels in ecosystems. Recently, I have focused on the quantitative modelling of the resilience of species and system responses to climate changes.

If you are interested in becoming a MSc or PhD student please feel free to contact me. Below you can find some of the current projects in my group.

Current research projects

1. Adventdalen Integrated Research Operations (ANCHOR)

As a strategic research platform, ANCHOR will provide a broad base of knowledge and education necessary for an integrated understanding of how the Arctic terrestrial ecosystem in Adventdalen is structured and functions under long-term environmental and climatic changes. Specifically, ANCHOR embraces (i) short-term research projects and (ii) long-term monitoring with (iii) the Arctic education at the University Centre in Svalbard (UNIS) in Longyearbyen. ANCHOR embraces the spatial diversity in terrestrial ecosystem dynamics across the Arctic by initiating comparative research, monitoring and educational activities between Svalbard and Greenland, specifically with the research facilities at Station Nord and Zackenberg in North and Northeast Greenland, respectively.

Currently, two long-term projects are affiliated with ANCHOR, one monitoring project focusing annual changes in the number and demography of the reindeer population in Adventdalen and one project monitoring the spatio-temporal variations of the vegetation (phenology, performance, diversity and biomass) in Adventdalen. Also, three short-term projects are active under ANCHOR. We are always seeking MSc and PhD students for projects under ANCHOR.

2. A greener Svalbard?

This project investigates the consequences of the polar decline in sea ice extent for the vegetation, reindeer population and their interactions in the Adventdalen ecosystem. Spatio-temporal changes in plant phenology, performance and growth will be analysed and contrasted with concomitant changes in the demography of the reindeer population. Also, A Greener Svalbard? will establish two new courses at UNIS and communicate the science and results through established public seminars on an annual basis. A Greener Svalbard? is part of the Adventdalen Integrated Research Operations (ANCHOR).

3. Sea ice induced vegetation growth dynamics in the Arctic

This project focuses on year-to-year autoregressive analyses of individual tree-rings sampled from Salix spp. and Betula nana throughout Greenland and Svalbard covering a period of approximately 100 years. In addition to direct effects of the sea ice extent on vegetation growth dynamics, the paper will also integrate aspects of indirect effects reflected in (i) the annual growth trade-offs and (ii) growth resilience. Both traits are estimated from the unique autoregressive structures of the inter-annual growth dynamics observed from the dendrochronological records in Greenland.

Read more here: Retreating sea-ice may lead to declined growth of tundra shrubs

4. Resilience dynamics in Arctic plant phenology

Phenological responses to changes in climate have been documented across a vast range of evolutionary divergent species. In particular, plants have demonstrated incredible ability to adjust their timing of flowering to climatic changes. Although discussions of resilience in phenological responses have gained momentum recently, including the potential existence of equilibria and associated recovery times, so far no quantitative models have been presented. Here, we bridge this important gab of knowledge and provide for the first time, a theoretical framework for quantifying the dynamics of resilience in plant phenology. We apply an autoregressive model to long-term (1996–2015) data of flowering dates of six Arctic plant species in high-Arctic Greenland. The analyses demonstrate that inter-annual changes in snow cover, a paramount climatic variable for flowering phenology in the Arctic, not only induces resilience dynamics with multiple attractors but also induces significant shift in resilience. This variance is evident across species as well as within species across biotypes.

Mads Forchhammer in UNIS news:

22.09.2017: Effects of sea ice on Arctic shrub growth: The importance of biotic interactions
06.06.2017: The Green Arctic – Plants as cornerstones in terrestrial ecosystems
05.10.2016: Climate change effects on Arctic species spread across trophic levels
28.06.2016: Reindeer count in Adventdalen



The University Centre in Svalbard
Telephone: +47 79 02 33 00
Fax: +47 79 02 33 01
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Address: P.O. Box 156 N-9171 Longyearbyen
Org. no. 985 204 454


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