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.
This project investigates how solar UV radiation affects planktonic food webs in the Arctic by changing the nutritional quality of the lower trophic levels. UV radiation has been documented to lead to oxidation of poly-unsaturated fatty acids (PUFAs) in phytoplankton. These PUFAs cannot be synthesized de novo by zooplankton, but are key molecules for the marine pelagic food web. A combined approach was chosen with both sampling of field data (physical as well as biological) and experiments which were carried out during two field seasons in Ny Ålesund in 2003 (april/may) and 2004 (may/june). In 2004, the main part of the field work consisted of an outdoor experiment where phytoplankton was exposed to different irradiation regimes, using the natural sunlight. Algae from all different treatments were used for feeding zooplankton in order to trace the transfer of irradiation-induced changes of the fatty acid composition in phytoplankton to the next trophic level. A number of additional parameters will be analysed as well, combined with the results of an extensive measurement series of both PAR- and UV light. The experiment was carried out on the old pier (Gamle Kaia), while the laboratory part took place in the Italian station ‘Dirigibile Italia’.
The submitted proposal aims to perform the monitoring of the pollen rain in the Greenland atmosphere by distinguishing the local pollen production, relatively low, from pollen grains originating from other Arctic areas. A regular monitoring of the atmospheric pollen content must be performed in order to evaluate the amount emitted and characterise the seasonality of the emission. A comparison with air mass trajectories must allow the modelling of long distance transport
It is well known that the atmosphere is a conveyor of microorganisms, and that bacteria can act as ice or cloud condensation nuclei, but clouds have not been considered as a site where organisms can live and reproduce. We could show that bacteria in cloud droplets collected at high altitudes are actively growing and reproducing at temperatures at or below 0°C. Since ~60% of the earth surface is covered by clouds, cloud water should be considered as a microbial habitat.
The 2003 field activity will be mainly dedicated to coring activity which includes: 1. the sampling of snow and ice cores from a Ny-Ålesund nearby glacier (midre Lovenbreen). 2. the collection of near coast (Kongsfjorden) and lakes sediments (maximum under pack depth 30 m). Sampling collection of ice and sediment cores will be performed using a portable, electric operated, sampling corer. The transport of all materials up to each sampling station should be performed with snowcats.
The project investigated small-scale biotic interactions between laminated microbial communities and meiofauna at light-exposed sediment-water boundaries of estuarine lagoons. The production and biological structure of these systems is mainly determined by complex processes at the sediment-water interface which depend on finely scaled patterns, requiring appreciation of how the biota interact within these scales. We tested whether changing light conditions and active emergence of the harpacticoid species Mesochra lilljeborgi and Tachidius discipes are mediated by the activity of benthic oxygenic and anoxygenic phototrophic microbes. Two hypotheses were tested which addresses to the question of causality between changing light conditions and active emergence of the harpacticoid copepods. (1)The harpacticoid copepods T. discipes and M. lilljeborgi will enter the bottom water during daylight when oxygenic photosynthesis of cyanobacteria and eukaryotic algae is blocked and conditions at the sediment-water interface have turned anoxic. (2)Both species will not emerge during dark exposures when transferred to sterilized sediments.
To recognize some life cycle strategies linked to adult development and reproduction in the Northern krill, Meganyctiphanes norvegica, in the Gullmarsfjorden population. Sampling of krill and analyses of the distribution of sex, body-size, moult and reproductive development stages.
The main objective was to investigate the importance of the sediment as a nutrient source for blooms of nuiscance filamentous algae. Nutrient fluxes from the sediment were hypothesised to be of greater importance in maintaining algal biomass than were nutrients originating from the overlying water column. We aimed to assess the relative importance of algal mats on sediment geochemistry and nutrient release under stillwater and controlled flow conditions. Using nutrient fluxes as a surrogate for ecosystem function, we wished to investigate the role of species richness in maintaining the integrity of nutrient diagenesis. In this context, it is not necessarily the number of species that is important in maintaining nutrient supply to algal blooms, but the contribution individual species make to mediate nutrient release.
The phsyiological and locomotive reaction to factors that influence environmental behaviour of Nordic krill from the Gullmarfjorden were studied in terms of swimming energetics, predator avoidence and food utilization. In a newly developed experimental approach, individuals were maintained under defined conditions in flow through chambers and continuously monitored for swimming activity and oxygen consumption. Chemical, physical and biological parameters were applied and the reaction of the krill determined. Stress levels, defined this way, will serve as a reference for unfavourable conditions in the field. Thermal characteristics of digestive enzymes from the midgut gland were furthermore identify the optimum conditions for nutrient assimilation. The results will contribute to the understanding of diel vertical migration, dispersion and aggregation of krill which, in turn is essential for the interpretation of ecosystem dynamics and trophic interactions.
The project as a whole consists of a number of sub-projects which are: a) Is female coloration a signal of quality? b) Do males conduct post-spawning mate choice through differential filial cannibalism? c)Do female preferences for male size change throughout the season? d)Do female common gobies compete for access to high-quality males? e)Are male reproductive decisions influenced by prior expectation of female quality? f)How is male-male competition over nest sites influenced by resource holding potential and resource value? g)How do parasites influence mate preferences in two-spotted gobies?
The general objective of this research concerns the quantitative and qualitative study of particulate matter retained in natural (sea-ice and sediment) and artificial (sediment traps) traps in order to determine the main origin (autochtonous and allochtonous) and the relative importance of different fractions of particulate matter and to follow their fate in the environment. To quantify the autochtonous origin of particulate matter, primary production, nutrient uptake, biomass distribution, phytoplankton community structure and fluxes in the first levels of the trophic chain will be investigated. Studies will be conducted in the sea-ice environment and in the water column and compared to the particle fluxes measured both in the water, using sediment traps and in the sediment, by radiometric chronology, in order to estimate the different contribution of these habitats to carbon export to the bottom. The zooplankton will be identified and counted and primary production, nutrient uptake and phytoplankton dynamics will be related to hydrological structure and nutrient availability in the environment. The Kongsfjord results particularly suitable for the main objective of this research as it is influenced by important inputs of both atmospheric (eolic and meteroric) and glacial origin and is characterised by a complex hydrological situation which may promote autochtonous productive processes, thus determining important particulate fluxes.
Symbion pandora is a commensal on Norway lobster (Nephrops norvegicus) with a very complicated life cycle. The species was described very recently and appointed to a new phylum, Cycliophora. Obviously nothing is known about the biology of this animal. The present study investigated the feeding biology of Symbion pandora. This was investigated by offering them two different high quality food items: Algae and mussel. Additionally, incubations with radiolabelled dissolved amino acids were done to estimate the energy contribution from DOM. A specific goal was to quantify the amount of organic matter taken in during one meal and estimate how much this contributes to the total energy requirement of internal budding, production of larvae etc. during the life cycle of the cycliophoran. This was done by autoradiography and radiolabel incorporation.
The aim of our work was to study the occurrence of inorganic carbon pumps in the cell membrane and their importance in the supply of C for photosynthesis in different macrophyte species. This was performed by checking and comparing responses of several green, brown and, especially, red marine macroalgae species under CO2 disequilibrium conditions in the presence of buffer and/or inhibitors of carbon uptake. In addition, the effect of the different treatments was also checked in the marine phanerogam Zostera marina.
The activity pattern is recorded by new techniques of real-time video tracking of the benthic activity. Electronic intelligent sensors allow the time analysis of benthic numeric objects with intensive automated recording sessions. We record the natural behaviour of several animals over 24h cycles. We also look into possible antagonistic behaviour, i.e. how animals feed when they have tubes close to each other and when feeding may occur in the same patches. Comparison is made between active motile surface deposit feeders and tubicolous surface deposit feeders. Activities of Amphiura filiformis, A.chiajei (motile burried Ophiuroids) and Melinna cristata (tubicolous Polychaete) are extracted by image analysis and quantified. Amphiura activity is restricted to its deposit feeding mode and no suspension feeding is present in the experiments. We also examine how addition of phytoplankton to the sediment will affect the feeding activity and if Amphiura and Melinna can locate patches of food. Dynamics of the response to food addition is studied.
Most studies of energetics in marine filter feeders have focused on animals living in steady state food conditions. However, copepods experience highly variable access to food because of food patchiness and behavioural avoidance of predators. For small copepods this is especially important since they lack the potential of energy storage, e.g. in the form of lipids. After a period of food deprivation Acartia tonsa show a compensatory increase in ingestion rate, but only temporarily and on the time scale of the gut filling time. The copepods are able to compensate for the lacking input of food. On the other hand, longer periods of starvation (6-14h) induce elevated ingestion rates that lasts longer than gut filling time. Under these circumstances other energetic factors influence the ingestion rate. Consequently, the energetics of the copepods are highly variable in a patchy food environment.
To asses the utility of a new range of microelectrode sensors in measuring the flux rates of oxygen and nutrients across the sedimentary diffusive boundary layer and into and through macrofaunal tubes and burrow structures.
In order to evaluate the capacity of mussels to accumulate pollutants and to enhance growth and physiological effects, an investigation was carried out in the Faroe Islands and in the Skagerrak. In March 2000, about 1500 mussels of proper dimensions (length ranging between 5 and 6 cm) were collected in the Kaldbak Fjord (Faroe Islands) on a 10m water column. Selected mussels were divided in 4 groups (320 each) and deployed in 4 different stations (one at the Faroe Islands and three in the Skagerrak). Semipermeable membrane devices (SPMDs) were also deployed in the same stations for the preconcentration of lipophilic pollutants. One month later (end of April-beginning of May) mussels and SPMDs were recollected and sent to different laboratories for the determination of various parameters.
Dose-response experiments using 5 different sediment concentrations of fluoranthene (Flu) and pyrene (Py) respectively. Measuring radioactive marked Flu and Py in brittlestars and polychaetes and microbial degradation of Flu and Py in sediment. Also growth rate of brittlestars and polychaetes and determination of regenerationtime of brittlestar-arms.
The aim of our visit to Kristineberg was to study the stable carbon and nitrogen isotope fractionation of Meganyctiphanes norvegica in response to different food supply, and to evaluate the importance of physiological processes (assimilation and growth) in generating the new stable isotope pattern. This calibration will contribute to the evaluation of the stable isotope method as an approach to the study of food sources of animals in the field.
Distribution • What is the current distribution of coral colonies in the North Sea? • Where are coral colonies located on the structures? • Do any colonies show evidence of exposure to drill cuttings? Monitoring & Environmental Recording • What hydrodynamic regime and levels of suspended particulate material are coral colonies exposed to? • Does the coral skeleton retain an archive of any past contamination? • Does skeletal growth vary over time and does this correlate with any past contamination? • How variable is the rate of coral growth and does this correlate with any environmental variables? Environmental Sensitivity • What effect does increased sediment load have on coral behaviour and physiology? • What effect does exposure to discharges (e.g. cuttings and produced water) have on coral behaviour and physiology? • Are such exposures realistic in the field?
(a) To assemble and further develop an integrative methodology for in situ evaluation of the effects of turbidity and hypoxia on fish physiological and/or behavioural performance. (b) To determine experimentally the threshold values beyond which oxygen and turbidity levels are liable to alter fish physiological and/or behavioural performance. (c) To integrate the results obtained in a conceptual and predictive model. Main expected achievements:  establishment of a link between laboratory studies, studies in mesocosms and field studies, using the most advanced techniques for monitoring behaviour in various environmental conditions.  an understanding of the impact of water turbidity and oxygenation on three major components of the behavioural repertoire of fish: habitat selection, predator-prey interactions and schooling-aggregation.  Predictive ability for the effect of the environmental variables studied on ecologically relevant behaviour.