Terrestrial ecosystems

Previous research has revealed coupled dynamics in populations of reindeer, geese and foxes (Fuglei et al. 2003; Hansen et al. 2011; 2013) in relation to climate change related extreme weather events like rain-on-ice and the lack of sea ice. Bottom-up and top-down effects have been identified, but vary in intensity between years. In addition, the predator community for nesting birds is becoming more divers with increasing numbers of glaucous gulls, great skuas and polar bear predating on all life stages of the birds.

Insect studies have mainly focused on the presence and adaptation of individual species, but rarely been integrated in food web interactions as they are major components of the diet of some birds.

This working group will focus on the interaction among monitored species and the interaction with other working groups on factors determining population size. COAT forms the basis for this working group and will specifically address the reindeer-fox-barnacle goose-vegetation interactions.

Contact persons: Åshild Pedersen (NPI) and Maarten Loonen (UoG)

Tundra vegetation is usually a mixture of vascular plants, mosses, lichens, cyanobacteria and microscopic algae, each adapted to local conditions in the microclimate, nutrient concentrations, hydrology, biological interactions and other chemical and physical soil characteristics.

Studies on individual plant adaptations, succession, diversity, functional groups and the effects of snow, ice and grazing have been performed on different scales from small plots to the landscape level with remote sensing.

The aim of this working group is to reach out specifically to the other working groups with data already collected and determine knowledge gaps to understand dynamics and interactions within the terrestrial ecosystem.

Contact persons: Masaki Uchida (NIPR)

The soil is full of biological activity, including the breaking down of organic material, which in turn affects nutrient availability and modifies gas emissions. Microbial biodiversity and activity can be studied by using DNA profiles.

The interface between anoxic and oxic conditions and the transition between frozen and unfrozen ground have shown to be important regulators. Moreover, biological soil crusts with primary producers like cyanobacteria and microalgae influence the hydrological and thermal properties of the soil and potentially prepare the substrate for the colonization by mosses and higher plants.

This working group will focus on soil processes which are determined by permafrost, hydrology and organic material and affect the activities of the other working groups.

Contact persons: Mette Svenning (UiT)

Future emissions of CO₂ and CH₄ are forecasted to increase as a result of rising air temperatures and their effect on permafrost through both the physical release of GHGs from unfrozen soil and the increased soil microbial metabolism.

On the other hand, the contribution of vegetation in sequestering CO₂ should also be considered. Measurements of gas fluxes at the ecosystem, the plot and the soil level, in particular at different soil depths, can be directly related to results obtained by the other WGs focussing on vegetation dynamics, soil processes and communities and freshwater systems. This is because in particular for CO₂, the contribution of higher plants, of other photosynthetic organisms and of soil microbial respiration will contribute to carbon flux dynamics.

Due to the tight connection between vegetation, microbial metabolism and nutrient fluxes, nitrogen fluxes will be analysed both in soil and in living organisms and the resulting flux calculations will be used for predicting the future response of the different components of the terrestrial ecosystems.

Contact persons:  Masaki Uchida (NIPR)

This work group will provide the needed baseline data on the biodiversity and functional genetic make-up of freshwater communities in the water column, the benthos and the sediments of lakes, wetlands and rivers.

In addition, the WG will develop projects to quantify the effects of internal and external factors on the food web structure in freshwater systems and their ecosystem functions, including primary production, nutrient dynamics, and the microbial mediated conversions of allochthonous and autochthonous organic matter into greenhouse gasses (i.e., CO₂, CH₄ and N₂O).

The internal and external factors include vegetation dynamics in response to the activity of terrestrial grazers (WG1 and WG2), as well as changes in temperature, water column stability, the moisture balance, and snow and ice cover.

Lakes are also integrators of these changes, and can therefore be used to reconstruct long-term variability in the terrestrial environment by analyzing biological and biogeochemical proxies in their sediments. This can provide a context of natural variability against which recent and future changes in terrestrial and lacustrine ecosystems can be compared.

Contact persons: Elie Verleyen (Uni Gent), Dirk Mengedoht (AWI), Josef Elster (Uni S-B)

While the other workgroups focus on bridging knowledge gaps within compartments and providing relevant data for other compartments of the ecosystem, this workgroup will focus on
(i) an overall integration of processes and fluxes
(ii) studying the sensitivity and resilience of the terrestrial biome in Ny-Ålesund to climate change
(iii) considering different levels of ecosystem organization by taking levels of space and time into account.

A scientific review and opinion publication will be an important product of this WG. This workgroup will also develop links with the other flagships in Ny-Ålesund and SIOS to ensure an efficient description, storage and exchange of data.

This group will work following a cyclic process of gathering information from the other working groups, providing an integration, describing knowledge gaps and subsequently disseminating their conclusions to the relevant working groups.

This working group will also be responsible for outreach and education of the results and the overarching insights obtained by the terrestrial flagship program.

Contact persons: Maarten Loonen (Uni Groningen) and Elie Verleyen (Uni Gent)