Svalbard: projects/activities

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.

Photoinhibition of photosynthesis by UV radiation, the formation of UV-screening pigments, DNA damage by UV radiation as well as DNA repair mechanisms will be determined in marine macroalgae of the Kongsfjord. Moreover, algae from different water depths will be transplanted by divers into areas with opposite light climate or covered by UV-screening filters and their physiological reactions tested. Additionally, the susceptability of the unicellular algal spores to UV-radiation will be tested. The results will allow insights into the effect of UV and photosynthetically active radiation on the zonation of macrocalgae and on the structure of phytobenthic communities. The data will be used to model the effects of increased of UV-radiation due to stratospheric ozone depletion on the Kongsfjord phytobenthic communities.

The changes in the stratospheric ozone layer due to anthropogen emissions lead to an increasing insolation of sunlight in the UV-B range (280nm - 320nm) on ground. One of the major objects of UV-B measurements is to detect long-term trends. The most interesting areas corresponding to ozone depletion are Antarctica and more recently the region around the northern pole. In interdisciplinary cooperation the data are also basis for research in the effects of increasing UV-B doses on plankton, algae, and other organisms. Since 1998 additional measurements of UV-A radiation (320-400nm) are done.

The aim of this international project is to measure and model arctic UV-radiation and assess the effects on freshwater planktonic organisms and foodwebs. The fieldwork and experiments are conducted at Ny-Alesund, Spitsbergen. The specific aim of our participation is to study the food web effects of UV-B stress by means of in-situ enclosure studies. In the laboratory we found that UV-B stressed algal cells may increase in volume and form a thicker cell wall. These changes in the algal cells may reduce their digestibility by zooplankton. Further the role of photopigments (like melanin and carotenoids), present in some zooplankters, will be studied in relation to the survival of these animals at high UV-B exposure. Research activities Grazing experiments with Daphnia pulex (melanic and hyaline) are performed in in-situ enclosures (under different UV exposures) in the Brandal Lagune during July. The green alga Chlamydomonas will be incubated in-situ under different UV exposures to assess the potential use of this alga as a biodosimeter for UV-B. Further the survival of melanic and hyaline daphnids will be tested in-situ.

The present project includes one pilot study of wild adult glaucous gull (Larus hyperboreus) and one experimental study of glaucous gull chicks raised in captivity. The pilot study of adult gulls gave us enough blood and tissue samples to develop the methods needed for immune system analysis in the laboratory experiment. In the experimental study a total of 39 glaucous gull chicks were hatched and raised in captivity in Svalbard, Norway. The chicks were divided into two groups. One experimental group (20 chicks) was given food that mimicked the “natural” food found in the marine environment. The control group (19 chicks) was given “clean” food. After 56 days the chicks were sacrificed in order to collect samples for analyses of organochlorines (OCs) and immunocompetence measurements. The experimental group had 2.8, 3.9, 5.0, and 6.1 time’s higher concentrations of HCB, Oxychlordane, ?DDT, and ?PCB, respectively, compared to the control group at day 56. All chicks used in the experiment were immunised with various vaccines and sera in order to test their ability to respond against foreign antigens. The experimental chicks produced low levels of virus neutralising antibodies when tested against the herpes virus and reovirus. They produced higher levels of neutralising antibodies when tested to tetanus toxoid. There was, however, no difference between the experimental groups with regard to the mean antibody titres. The chicks in both groups also responded to the influenza virus by increasing the production of specific antibodies. However, the mean antibody titre in the exposed group was significantly lower than in the control group. The mitogen-induced response of blood lymphocytes to PHA and LPS was significantly higher in the exposed group compared to the control group. The specific response of blood lymphocytes to Con A, PWM, KLH, TET, and PPD was higher in the exposed group compared to the control group. However, do to high variance in the exposed group there was no significant difference between groups with regard to the lymphocyte response to these mitogens. The results from the present study indicate a toxic effect of OCs on the glaucous gull chicks, which induced a systematic activation of the immune system. Further work on data will be performed.

The study covers many areas of ecotoxicology research on polar bears. Monitoring of POP levels and studies of effects on endocrine disruption, immune system, reproduction, and demography are all parts of the study.

The project aims to describe the environmental status of marine sediments in van Mijenfjorden. This to provide baseline data of contaminants and biodiversity, as well as for monitoring of eventual contamination from industrial activities (coal mining).

Investigation of benthic faunal communities for: taxon distribution/ biodiversity mapping; examination of effects of glacial and physical disturbance on community structure; relation between faunal structure and sediment contaminants.

The project aims to carry out an environmental assessment of the marine environment close to the three main settlements in the Isfjorden complex; Barentsburg, Longyearbyen and Pyramiden. The study comprises analyses of sediment geochemistry and soft-bottom benthic fauna. Attention is given to distinguishing atmospheric transport of contaminants from those arising from local sources.