The full list of projects contains the entire database hosted on this portal, across the available directories. The projects and activities (across all directories/catalogs) are also available by country of origin, by geographical region, or by directory.
The main research goal of this project is focused on trophic interactions within microbenthic communities in aquatic systems. Grazer-microalgae interactions are investigated by conducting field and laboratory experiments in order to get a closer idea of the microphytobenthos community structure itself. Especially the role of morphological and physiological adaptations of microalgae in the presence of specific meio- and macrofaunal predators are of great interest. In addition to that we have devised a new benthic sensor for the quantitative and qualitative assessment in situ of diverse populations of microphytobenthos with high spatial and temporal resolution, enabling rapid evaluation of the community structure and distribution.
To study the organisms involved in phytoplankton succession and the Key factors involved. This includes Bacteria-Algae, Algae-zooplankton and Zooplankton-Fish interactions. Aspects such as algal-grazer defence mechanisms and digestability of alage are core topics.
Cellphysiological investigations of the effects of marine secondary metabolites on isolated (sensory) cells
Effects of UV-B radiation on microbial communities in Kongsfjorden in relation to metal and dissolved organic matter availabillity.
The succession of macro- and microalgal communities in the Antarctic will be investigated in field experiments under various UV radiation (UVR) conditions and in the absence or presence of grazers. The observed differences in the succession process will be correlated to physiological traits of single species, especially in spores and germlings, which are the most vulnerable stages in their life histories. Photosynthetic activity of the different developmental stages will be measured routinely. Additionally we plan the determination of pigment composition, C:N ratios, content of UV protective pigments and of possible DNA damage. The experiments will start in spring, concomitant to the time of highest UVBR, due to the seasonal depletion of the ozone layer in the Antarctic region. Supplemental laboratory experiments will be conducted to determine the effects of UVR on spores and germlings of individual species. In addition to the above analyses, we plan to examine of UVR induced damage of cell fine structure and of the cytoskeleton. The results of both the field and laboratory experiments will allow us to predict the consequences of enhanced UVR for the diversity and stability of the algal community.
Marine invertebrates show a large variety of feeding strategies. These comprise mechanisms for catching prey, the uptake of food and the utilisation of various food sources. Morphological and anatomical adaptations allow for the capture and the ingestion of the food. However, the organism's physiological properties are the key for the efficient digestion, the nutrient uptake and the assimilation of food. In response to environmental factors marine organisms have developed highly specialised biochemical adaptations which are particularly reflected by the immeasurable diversity of digestive enzymes. The detailed function of digestive enzymes in marine invertebrates and, particularly, their synergistic interplay is still poorly understood.The overall aim is to investigate the mechanisms of enzymatic food utilisation and enzyme induction in different taxa of marine invertebrates in response to environmental factors.
Radioactivity in the Arctic environment is a central topic within environmental pollution issues. Increased discharges of technetium-99 (99Tc) from the nuclear fuel reprocessing plant Sellafield to the Irish Sea has caused public concerns in Norway. This project (acronym “RADNOR”) includes model and monitoring assessments and improvements, assessment of current and novel abiotic and biotic dose parameters and dose calculations and use of realistic climatic background scenarios in order to assess corresponding consequences for transport of radioactive pollutants. RADNOR consists of three main components: part 1, the determination of levels and time series of 99Tc in benthic and pelagic food webs; part 2, containing working packages on improvements to the understanding of site-specific and time-dependent sediment-water interactions (KD), kinetics of accumulation (CF) and body distribution in marine organisms, including contaminated products for the alginate industry and part 3, dealing with model hindcasts and observations for spreading of 99Tc from the Sellafield nuclear reprocessing plant during the 1990s and improvement of the NRPA dose assessment box model. From the model outputs, doses to man and environment will be calculated resulting in a valuable database for use within environmental management and for decision makers.
Detection of UV-B induced DNA damage on zoospores of brown algae
The aim of this project is to investigate and understand those factors that play a role in the seasonal dynamics of different functional groups in the pelagic zone of coastal seas. We investigate the interactions between bacteria, phytoplankton, zooplankton and juvenile fish in order to assess the importance of biological interactions in the seasonal succession.
Description of parameters of the population dynamics of polar bivalve communities, first year: growth and reproductive cycle of the dominant Greenland cockles (Serripes groenlandicus)
The aim of this project is to investigate natural products from polar macroalgae. As arctic waters represent an extreme habitat, formation of secondary metabolites is limited - besides other factors - by light conditions. Therefore, the influence of light, particularly different photon fluence rates and UV radiation, on secondary metabolism and on regulation of associated genes will be studied.
The goal is to understand, how bacteria in Arctic sediments are adapted to low temperature and how (climatic) changes of temperature may affect the rate and pathways of carbon cycling and the balance of mineral cycles. The diversity and physiology of bacterial populations of fjord sediments on West-Spitzbergen will be studied by a combination of molecular (16S rRNA sequence analyses and in situ hybridization) and microbiological (isolation and physiology of pure cultures) approaches. The metabolic activity of these bacteria in the sea floor and the temperature regulation of the dominant mineralization processes will be analysed by experimentel techniques during the research period in Ny Ålesund. The focus will be on the enzymatic cleavage of polymeric carbohydrates, the anaerobic respiration through sulfate reduction, the reduction of iron and mangenese oxides, and the turnover of volatile fatty acids and hydrogen. Subsequently, psychrophilic bacteria are isolated from the anoxic sediments and studied in pure culture. The bacterial populations in the sediment are studied by molecular methods to analyze their diversity and metabolic activity.
Study of the energy exchange between atmosphere, sea ice and ocean during freezing and melting conditions; within that, measurements of solar radiation (visible and UV) and optical properties, snow and sea ice characteristics, vertical heat and salt fluxes, oceanographic parameters.
During the spring/summer transition, sea ice and snow properties change considerably in response to warming and the eventual reversal of temperature gradients within the snow and ice. Snow melt water percolates down towards the colder snow/ice interface, where it refreezes to form superimposed ice. On sea ice this process occurs probably longer and more intensive than on land, because throughout the summer the ice and underlying seawater is always colder than the snow. In Antarctica superimposed ice may actually form layers of some decimeters in thickness. The objective of this study is to investigate the main processes and boundary conditions for superimposed ice formation, in recognition of its importance for Antarctic sea ice, and its possible importance for Arctic sea ice in case of environmental changes due to future climate change. This will be performed by means of modeling as well as by combined measurements of the temporal evolution of snow and ice properties and the energy budget.
As a result of the increasing atmospheric CO2 levels and other greenhose gases due to anthropogenic activities, global and water temperature is rising. The objectives of our project might be summarized as follows: I. To measure the activity of the enzymatic systems involved in carbon, nitrogen and phosphorus uptake (carbonic anhydrase, nitrate reductase and alkaline phosphatase) in selected macroalgae. To assess the optimal concentration of inorganic nitrogen and phosphorus for growth and photosynthesis. To study the total concentration of carbon and nitrogen metabolites in the macroalgae (proteins, total carbohydrates, and lipids) in order to define the possible existence of nutrient limitation. II. To simulate the conditions of climate change, represented as CO2 enrichment and increasing UV radiation, on the activity of carbon, nitrogen and phosphorus uptake mechanisms. III. To screen the activity of the enzymatic systems previously detailed in macroalgae from the Konjsfjord, in order to know their nutritional state.
To distinguish between atmospheric and marine transport of contaminants to northen latitudes by comparison inventories of lake and fjordic sediments.
Effects of POPs on the immune system in the glaucous gulls
Measurements of the changes when growing ice is depositing salt into the fjord.
Observation how UV-radiation affects recruitment on hard substrate in the upper sublitoral zone.
1. To quantify benthic community parameters for all size classes of fauna across the Oxygen Minimum Zone (OMZ) 2. To make a detailed assessment across the OMZ of a) sediment accumulation, mixing and irrigation rates and depths and b) environmental factors acting as controls on faunal activity 3. To characterise solid phase and porewater geochemistry of sediments across the OMZ 4. To assess a) faunal digestive Organic Matter (OM) alteration, b) the relative importance of chemo- and photosynthetic food sources, and c) benthic food web structure, across the OMZ 5. To determine porewater profiles and benthic solute fluxes in situ, and to assess faunal OM assimilation and trophic relationships by monitoring tracers during shipboard and in situ incubations 6. To obtain high resolution porewater profiles of oxygen and other key analytes, free of pressure and other effects potentially introduced by core recovery 7. To determine in situ oxygen consumption rates and benthic fluxes 8. To use labelled tracers to assess mixing and irrigation rates, faunal OM assimilation, and size-selective ingestion and mixing 9.To determine sediment denitrification and sulfate reduction rates and their contributions to OM remineralisation