Projects/Activities

Variation in primary sex characters of wrasse in relation to reproduction strategy and environmental conditions:

Mosses and lichens are important components of arctic ecosystems as well as being an internationally important component of the biodiversity of the British Isles and Scandinavia. They are typically associated with nutrient poor ecosystems and are often eliminated with increased supplies of nitrogen. This study is part of a programme examining the impact of elevated nitrogen in nutrient poor ecosystems on mosses and lichens. This particular study will examine the contribution of airborne nitrogen in the form of ammonia to the growth of mosses in the arctic tundra in Kongsfjord. Breeding colonies of seabirds deposit large quantities of guano, which can be major sources of nitrogen as well as heavy metals (Headley 19xx) and other contaminants in the marine ecosystems. The nitrogen in fish and other organisms high up in the marine food chains have higher concentrations of the heavier stable isotope of nitrogen called 15N. The ratio of this isotope to the usual isotope of nitrogen (14N) can be used as a marker as to the relative contributions of different forms of nitrogen that are being utilised by an organism. By taking samples of moss at different distances from seabird colonies and analysing these and the soil and guano for the concentrations of the two stable isotopes of nitrogen (15N:14N ratio) the relative contributions of nitrogen from the soil and atmosphere can be determined. This can then be utilised along with details of the relative abundance of the mosses along transects away from seabird colonies to ascertain how important atmospheric ammonia is in altering the species composition of moss communities.

Five French Scientists orginating from the Observatoire Océnologique de Banyals, stayed at the Kristineberg Marine Station during two weeks.

Please contact Dr Clare Robinson

Please contact Dr Cornelius Lutz

In 2001 we were granted an LSF award for work on dissolved organic nitrogen in arctic ecosystems. In collaboration with Bjorn Solheim and Christina Wegener of the University of Tromso, we studied (a) the DON and DIN content of a range of soils around Ny Alesund and (b) the relative uses of nitrogen fixation and DON in a defined range of communities. We established a long term experiment at Stuphallet on dry tundra, where we made additions of nitrogen to fixed quadrats. The nitrogen additions were of nitrate, ammonium, glycine and glutamate at 10 kg ha-1. This is the first long-term experiment where organic N additions have been made to tundra. Our hypothesis is that DON is a preferred N source for tundra angiosperms. Within 10 days of application of the N in 2001, there were no significant changes in plant chlorophyll content or N content, not surprisingly as the plants were fruiting and end-of-season N retranslocation and leaf loss were in progress. This application is to make measurements on these plots to test the hypothesis after one year, and to make further applications.

To examine the way in which light intensity and spectrum affects the swimming behaviour and activity of the pelagic euphausiid Meganyctiphanes norvegica.

The project is part of a large comparative study on the evolution of the development of crutaceans, mainly malacostracans (higher crustaceans).

The high Arctic contains delicate, relatively pristine ecosystems that are increasingly subject to exported aerial pollution (e.g. nitrogen) and higher than average climatic temperature change. Together these factors may potentially change important biogeochemical processes (e.g. the cycling of carbon and nitrogen) and ecosystem dynamics. This project involving the University of Nottingham, The British Geological Survey and IACR Rothamsted is now entering its second field season. The project concentrates on the release and the subsequent fate of N, entering the tundra ecosystem, as a pulse during the spring thaw. The questions we propose addressing are (i) how important is this event in transferring enhanced N deposition to tundra ecosystems, and how much is lost as run-off to lacustrine and inshore marine environments, (ii) how does enhanced N affect the carbon cycle (i.e. plant growth, decomposition processes) and (iii) what is the impact on soil N mineralizationimmobilization dynamics. Two plot experiments have been set up at contrasting vegetation sites around Kongsfjorden (Brandalspyntyn and Ny-London). We have simulated the release of N from the snowpack by applying 15N label as the snow has melted. An accurate audit regarding the fate of this snowpack N can then be made (i.e. does it remain in the soil, enter the tundra flora and soil microbiology or is it lost from the system). In addition, using techniques for combined 18O+15N analysis of nitrate, we can distinguish between atmospheric- and soil-derived nitrate. This will allow us to assess and source losses of N from the tundra during the brief summer growing season. These complementary approaches will provide a quantitative understanding of the fate of deposited N in the pristine Arctic environment. The overall aim will be to parameterize an N-flux model for this important ecosystem.

The high Arctic contains delicate, relatively pristine ecosystems that are increasingly subject to exported aerial pollution (e.g. nitrogen) and higher than average climatic temperature change. Together these factors may potentially change important biogeochemical processes (e.g. the cycling of carbon and nitrogen) and ecosystem dynamics. This project involving the University of Nottingham, The British Geological Survey and IACR Rothamsted is now entering its second field season. The project concentrates on the release and the subsequent fate of N, entering the tundra ecosystem, as a pulse during the spring thaw. The questions we propose addressing are (i) how important is this event in transferring enhanced N deposition to tundra ecosystems, and how much is lost as run-off to lacustrine and inshore marine environments, (ii) how does enhanced N affect the carbon cycle (i.e. plant growth, decomposition processes) and (iii) what is the impact on soil N mineralizationimmobilization dynamics. Two plot experiments have been set up at contrasting vegetation sites around Kongsfjorden (Brandalspyntyn and Ny-London). We have simulated the release of N from the snowpack by applying 15N label as the snow has melted. An accurate audit regarding the fate of this snowpack N can then be made (i.e. does it remain in the soil, enter the tundra flora and soil microbiology or is it lost from the system). In addition, using techniques for combined 18O+15N analysis of nitrate, we can distinguish between atmospheric- and soil-derived nitrate. This will allow us to assess and source losses of N from the tundra during the brief summer growing season. These complementary approaches will provide a quantitative understanding of the fate of deposited N in the pristine Arctic environment. The overall aim will be to parameterize an N-flux model for this important ecosystem.

Seals studies

HIMOM will aim to provide a system of methods, the so-called Hierarchical Monitoring Methods (or HMM), to determine system status and changes which are expressed by biological and physical variations within inter-tidal areas. The HMM will aim to provide a management strategy tailored to the needs of End User involved in activities relating to the sustainable development of tidal flat areas around Europe. The HMM system will represent a hierarchical suite of activities, ranging from simple ground measurements of biota and physical characteristics to remote sensing of spectral reflectance properties for the analysis of basin scale systems.

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.

The photosynthetic productivity and the factors affecting it are measured in the nival zone of the Alps. Patterns of CO2 exchange for several lichen species are determined whilst recording environmental factors such as light and temperature and lichen water content. Whilst these records will show the lichen response over the year they can most easily be interpreted when the photosynthetic ability of individual lichens is well known. To achieve this the response of each species to light intensity, temperature, thallus water content and humidity will be determined under fully controlled conditions in the laboratory. The final aim is to achieve an initial carbon balance model for the lichen species. This will be aided considerably by the deploying of a continuously recording chlorophyll fluorescence system that will provide activity data for one lichen species on a better than hourly basis throughout the year.

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.