Projects/Activities

To investigate arctic foxes physiological adaptations to life at high latitudes. Resting and running metabolic rates, body weight, food intake, body core temperature, heart rate, and blood parameters were examined during different seasons and during periods of food deprivation.

Biological nitrogen fixation by cyanobacteria is a key process for productivity in terrestrial Arctic ecosystems and the activity is dependent of size and diversity of cyanobacterial populations. Changes in biodiversity after pertubations of different types of habitats simulating climatic changes or other antropogenic effects will be studied by molecular methods and correlated to variations of nitrogen fixation activity.

The structure and role of the cyanobacterial communities that colonise bare soils and fix nitrogen in the arctic ecosystem will be studied. The planned activities will focus on the isolation, identification and characterisation of cyanobacteria from arctic habitats and on the changes of the cyanobacterial community along a transect from a retreating glacier front to a more stable habitat characterised by the presence of mature vegetation. For these purposes, a polyphasic approach encompassing microbiological, morphological and molecular techniques will be applied to environmental samples and isolated cultures. The obtained results will give new insights on the diversity and role of nitrogen fixing cyanobacteria in the arctic and, in more general terms, on ecosystem development under changing climatic conditions.

To evaluate temporal variation in arctic fox numbers and their food resourses in the Kongsfjorden area. The number of foxes captured per 100 trap-days are used as an index of fox density termed "Fox Capture Index". The observations of denning activity i.e. observation of number of arctic fox litters and litter size at den are termed "Fox Den Index" as a second index of fox abundance. A third index is termed "Fox Observation Index". This index is based on both observations of adult foxes seen away from breeding dens pr 100 h field work and reports on request from scientists and local people on observations of adult foxes during summer. In addition, reports on observation of fox tracks in the study area were collected in 1990-2001 as a fourth index, which were called "Fox Track Index". The field census are conducted for 10 days starting at the end of June. All dead foxes in the area should be collected.

The aim of this programme will be to study the mechanisms of the regulation of the body fuel utilizon and energy expenditure during fasting

Energy allocation

Parental effort, the extra energy expenditure above maintenance levels devoted to the care of affspring, has been postulated to incur a fitness cost.

The objectives of this project is to study the effect of environmental stochasticity on the Svalbard reindeer population dynamics, nad further evaluate how this may affect reindeer-plant interactions.

Observation how UV-radiation affects recruitment on hard substrate in the upper sublitoral zone.

1. Analysis of existing data from the current shellfish monitoring programmes in order to design a suitable sampling strategy 2. Ideentification of toxic algal species in UK waters 3. Construction of a detailed time-series at several key sites in the UK for toxic phytoplankton and shellfish toxin occurence 4. Comparison of the genotype versus toxicity of suspected toxic species between sites

This study will be part of the EU project NTAP. The overall objective of NTAP is to provide a unified conceptual framework for nutrient dynamics as modulated by the interaction of turbulence and plankton and to use this information to aid in implementing and modifying legislation on coastal water quality and management. Specifically, the objectives are a) to build a database on turbulence effects by gathering existing scattered data, b) to produce experimental data on key organisms, interactions and mass transfer rates, c) to develop a sensor for laboratory measurement of small-scale turbulence, and d) to produce a dynamical model at community level with exploratory and predictive capabilities. The present project will fit within Objective b), and will complement other NTAP experimental studies with cultures and natural communities that are being carried out in different European laboratories. The results derived from this project will also be valuable to test and calibrate the model developed within Objective d).

Four-week mesocosm study with the following objectives: - to identify environmental and biotic factors in control of the production, chemistry and fate of exportable DOM in a coastal environment - to follow how DIN and DIP are transformed to DON and DOP and to measure their mineralisation - to analyse the optical properties of new DOM and to measure how radiation might change the optical properties - to validate current community-nutrient models for the marine system with particular emphasis on the mechanisms regulating shifts between carbon- and mineral nutrient limitation of bacterial growth rates, - to produce experimental data for further development and modification of the plankton community-nutrient model and – to incorporate DON and DOP into the present community-nutrient model.

Many marine sponges produce and store pharmacologically-active metabolites. There is an ongoing discussion as to whether some of these compounds are produced by the sponge itself, or by associated bacteria which can account for more than 60% of the sponge biomass. Co-metabolic activity between sponge cells and sponge associated bacteria (SAB) has also been postulated. Anaerobic bacteria are occasionally found in sponge tissue, though their contribution to sponge metabolism is completely unknown. There is increasing interest in biotechnological production of sponge biomass for sustainable use of this promising marine resource. Our studies will contribute to a thorough understanding of sponge-bacteria interaction, and form the basis for the development of biotechnological methods. Most research has been done on tropical and subtropical sponges. Participants of this project will apply, for the first time, microbiological and chemical studies on boreal sponges. Objectives: • Description of chemical conditions in sponge tissue: occurrence of microniches • Cultivation of specific groups of aerobic and anaerobic sponge associated bacteria • Establishment of novel methods for co-cultivation of sponge cells and bacteria • Identification of new bacterial biomarkers • Elucidation of connections between spatial distribution of associated bacteria and metabolites with a focus on anoxic zones and anaerobic microbial communities (especially sulfate reducing bacteria and Archaea) • Investigation of chemical communication and other interactions (´bacterial farming´) between sponge cells and bacteria as well as sponges and their environment

The project primary goal is to relate among-year variation of tundra wader numbers and nesting success to breeding conditions on southeastern Taimyr.

The objective of the planned work with arctic higher plants is to study the range of adaptation of photosynthetic metabolism, of antioxidative and sun screen compounds in a cold and reduced UV-B climate in comparison of data already raised from high alpine plants, which live partially under stronger cold and under different light regimes, especially higher UV-B. Further, the ultrastructure of leaf cells will be studied to clear, whether adaptations found in some high alpine plants occur similarly in arctic plants, and to connect such cytological results with metabolic functions. An additional comparison will be made with snow algae from Svalbard compared to those harvested on high alpine snow fields. It is the advantage of the planned work, that a number of investigations ranging from ultrastructural studies over different aspects of photosynthesis to assays of UV-B sensitive compounds and antioxidants will be conducted mostly with measurements and sample collection in the field during the same experimental day at one place. Therefore we expect a good connection of the data raised, back to the plant system and expect a much broader description of vitality and adaptation under the current conditions.

The polar pteropod Clione limacina is characterised by high quantities of lipids with ether components (1-O-alkyldiacylglycerol=DAGE) in combination with odd-chain fatty acids. It is unknown why Clione and probably other pteropods have specialised in this manner. Furthermore the precursor of the biosynthesis of these compounds is still unknown. Therefore samples of Clione limacina and its only prey Limacina helicina will be collected by using plankton nets from small boats. The species will be kept in aquaria and feeding experiments with both species and food of different composition and nutritional value are planed.

Benthic macroalgae communities of the arctic ocean provide habitat, protection, nursery and nutrition to a large number of invertebrates. In contrast to temperate and tropical regions the basic ecological interactions between zoo- and phytobenthos of the Arctic are little understood. Therefore this project for the first time investigates biological and chemical interactions between invertebrates and macroalgae on Spitsbergen/Svalbard (Koldewey Station) with special emphasis on defense mechanisms against grazing pressure. Initial diving-investigations will map the invertebrate fauna which is associated with the macroalgae; the following feeding-experiments with herbivorous animals aim to selectively identify generalists, generalists with preference or specialists. Additional bioassays serve to reveal structural and/or chemical properties of those plants, which affect a specific impact on the grazing of herbivores. Our investigations on the chemical protection of the algae against grazing focus on the basic mechanisms and the chemical structure of potent secondary metabolites carried out in cooperation with natural product chemists.

Succession of communities and individual growth of benthic invertebrates are more or less unknown in polar waters, but nevertheless are the basic parameters of understanding the benthic sub-ecosystem, delivering data for modelling and prediction of the system´s development. Three localities, two in the Antarctic and one in the Arctic, the Kongsfjord in Spitsbergen, have been choosen as investigation localities. Hard and soft substrates, which will be sampled in regular intervalls during the duration of the project, will be deployed at different depths. The analysis includes species composition, species growth and, with respect to soft substrates, sediment parameters.