Projects/Activities

This study aims at reconstructing the Barents Sea marine ecosystem before the exploitation by man. This reconstruction will be made by using the existing archival resources on catch statistics from the 17th to 19th centuries in the Netherlands, Germany, Denmark and the United Kingdom, in combination with the present knowledge an animal behaviour and food web structure. Fieldwork is planned in two former hunting areas in Spitsbergen: the Smeerenburgfjord and the Storfjord to study both the structure of the recent marine ecosystem and the composition, size and dating of the recent bird rookeries. This information in combination with the historical data will be used to reconstruct the original ecosystem.

The ecology of the Greenland Right Whale is studied using the historical information from written sources from Dutch archives. The Spitsbergen and Davis Strait populations of the Greenland Right Whale were so heavily hunted that they are almost exterminated now in the northern waters. The whale bones on the beaches of Arctic islands are the archaeological evidences of this exhausting hunt. Very often whaling logbooks, crew statements and lists of catch figures are the only sources of information preserved of this animal in these regions. In this project recent biological information of the animal in the seas around Alaska and historical information of the whale in the North Atlantic and Davis Strait is used to reconstruct the migration, distribution and ecological behaviour of the Greenland Right Whale in the North Atlantic Ocean.

The overall objective is to assess the influence of increased UV radiation and temperature on photosynthesis, nutrient uptake and primary production of microphytes. In order to do this, the existence and nature of strategies against potential UV damage in marine macrophytes of different climatic regions will be investigated. Research activities Measurement of photosynthesis using oxygen exchange and variable fluorescence (PAM); determination of oxidative stress (Gluthation, SOD, CLSM) and nutrient uptake under different UV-regimes

In the seventeent and eighteenth centuries intensive European whaling and walrus hunting took place in the waters around Spitsbergen, with many stations on the coast of the islands. The hunt was carried out in areas along the edge of pack ice and is therefore very sensitive to changes in the ice situation and climate. When, around 1650, climate and ice distribution changed, whales moved to the north. The whaling stations in the south of Spitsbergen were abandoned when stations in the north were still functioning. When, later, the ice situation deteriorated in the north as well, the stations were abandoned there too. Shore whaling changed into pelagic whaling. Because of these whaling and walrus hunting activities two very numerous large mammals were largely depleted and almost disappeared from the Spitsbergen waters. The pelagically feeding Greenland Right Whale and the bentically feeding walrus, whose initial stocks are estimated at 46,000 Greenland Right Whales and 25,000 walrus, were eliminated. This elimination has caused a major shift in the foodweb. The plankton feeding seabirds and polar cod strongly increased because of the elimination of the Greenland Right Whale, and the eider ducks and bearded seals increased because of the decrease of the number of walruses. This development has led to the enormous amount of seabird rookeries on the West coast of Spitsbergen.

The ecology and breeding success of the Longtailed skua (Stercorarius longicaudus) and the Brown skua (Catheracta lonnbergi) is studied in a longterm programme. The difference in allometric growth between the different species and populations of skuas is interesting when it is related to the ecology and distribution history of these species and populations. Skuas have a dynamic distribution history and an opportunistic way of living. Populations of the same species in different localities have often a different ecology. Therefore, studies on different populations of the same species are carried out.

The ecology and breeding success of the Long-tailed skua (Stercorarius longicaudus) and the Brown skua (Catheracta lonnbergi) is studied in a longterm programme. The difference in allometric growth between the different species and populations of skuas is interesting when it is related to the ecology and distribution history of these species and populations. Skuas have a dynamic distribution history and an opportunistic way of living. Populations of the same species in different localities have often a different ecology. Therefore, studies on different populations of the same species are carried out.

The principal aim of the project is to establish a link between the marine carbon and sulphur cycles, for which the marine phytoplankton taxon Phaeocystis sp. was chosen as a model organism. This colony forming alga is an important source of the volatile organic sulphur compound dimethyl sulphide (DMS), and its dense blooms can act as a carbon sink. By combining the expertise of researchers working on the carbon and sulphur cycles a thorough inventory of these chemicals will be made. This should result in a better understanding of the role of Phaeocystis blooms in the escape of DMS in the atmosphere and of carbon from the photic zone, and consequently of its role in climate control.

Elaboration of DUTCH-WARP [Deep and Upper Transport, Circulation and Hydrography-WOCE Atlantic Research Programme] in the frame of WOCE: deep circulation of thermal structure of surface water in the Iceland Basin; continuation of the application of ARGOS buoys; implementation of satellite altimetry of the North Atlantic Ocean; eastern boundary current of the North Atlantic Ocean in the Bay of Biscay as contribution to WOCE (1992-1998)

The development of methods for the accurate prediction of the extreme response of non-linear dynamic systems which use less computer time than presently commom methods.

In the wake of topical research issues such as global change and energy resources, one can recognize two priority targets for the study of fossil plant remains: - insight into the role of land plants and phytoplankton as monitors, recorders, motors and moderators of climatic and environmental change; -insight into the predictive value of organic remains with respect to genesis, composition, occurrence, quality and quantity of fossil fuel reserves. In harmony with these targets, current research at the Laboratory of Palaeobotany and Palynology (LPP) is aimed to provide for basic contributions to the palaeoecological study and interpretation of Palaeozoic, Mesozoic and Cenozoic plant life. Four interconnected areas of scientific emphasis are currently distinguished: - biotic change: documentation and causal analysis of changes of past plant biota in terrestrial and marine environments, both at short and long time-scales; - selective preservation: identification of the biological, physical and chemical factors that determine selective preservation of organic matter during transport, sedimentation and burial; - methodology: development and introduction of new analytical methodology relevant to the study and interpretation of fossil plant remains; - systematics: generation and compilation of systematic data aimed at the accurate identification and classification of fossil plant remains. Overview of results LPP strives after a balance between the study of land plant remains and organic-walled marine phytoplankton (mainly dinoflagellates). Research objectives are related to both short (latest Pleistocene-Holocene) and long time-scales (late Palaeozoic-Cenozoic). Short time-scales Modern land plant communities can be understood only in the light of their history since the onset of the last deglaciation (15,000 yr BP). In western and southern Europe this history is governed by the climatically induced spread of forest communities and their subsequent recession as man's influence expanded. Through fine-scale analysis (temporal and spatial, as well as systematic), of assemblages of microscopic and macroscopic plant remains, research concentrates on the accurate discrimination between autogenic, climatically induced, and anthropogenic vegetational change in contrasting physiographic entities: (1) crystalline mountains in France and the Iberian peninsula; (2) landscapes characterized by Pleistocene-Holocene eolian (sand, loess) deposition in the Netherlands and Germany; (3) fluvial plains in the Netherlands; (4) littoral landscapes in Portugal, and (5) Arctic landscapes of Spitsbergen, Jan Mayen and Greenland. Following earrlier research experiences with respect to the palaeoecological analysis of pollen assemblages from the Vosges (France), in the research period special attention was given to deciphering the complex, altitude related, late Pleistocene-Holocene pollen signals from other low mountain ranges. Results have demonstrated that the spatial distribution of vegetation patterns can be followed through time by recognizing: (1) common time-proportionate trends in pollen values, and (2) local pollen components characteristic for altitudinal vegetation zones and lake/mire development. Long time-scales For the recognition and evaluation of biotic change on long time-scales, LPP concentrates on the study of land plant and phytoplankton records from sedimentary successions that contrast with respect to: (1) time of formation (selected late Palaeozoic, Mesozoic and Cenozoic intervals); (2) paleotectonic and palaeogeographic history (intracratonic; passive and active plate margins); (3) depositional environment (terrestrial to deep-marine); and (4) biogeographic provinciality. Temporal and spatial distribution patterns of plant remains are explored for proxy variables indicative of terrestrial and marine environmental change. Investigated variables include land temperature, humidity, precipitation, runoff, sea-level, sea surface temperature, salinity, nutrient supply, productivity, organic burial rate and CO2 level. In the review period particular attention has been given to the development of palaeoecological models of dinoflagellate cyst distribution in marine sediments. It has been shown that: (1) the potential of dinoflagellates in Mesozoic and Cenozoic time-resolution may frequently exceed that of planktonic foraminifera and calcareous nannoplankton, and (2) dinoflagellates can be applied in novel ways to further the environmental understanding of depositional sequences and sedimentary cycles defined by physical (seismic, sedimentological) analysis. Although research related to global change programmes is generally restricted to the Late Tertiary-Quaternary, there is one notable exception. It is recognized that a better understanding of the patterns and processes of past mass extinctions can contribute to an understanding of present and future man-induced extinction processes. Work by LPP concentrates on the profound biotic crises at the Permian/Triassic (P/Tr) and Cretaceous/Tertiary (K/T) junctions. Study of the P/Tr land plant record has now revealed ecosystem collapse in the terrestrial biosphere. At the K/T junction, it has been demon-strated that dinoflagellates have remained immune to extinction. Independent of configurations predicted by meteorite-impact or massive volcanism, therefore, palynological studies enable high-resolution reconstruction of environmental change, both during pre-crisis times and the phases of K/T ecosystem decline and recovery.

The global thermohaline circulation is driven by sinking of cold, dense surface waters in the Greenland and Norwegian Seas and its replacement by warmer surface water from lower latitudes. This global circulation system, the conveyor belt, is the main regulator of global climate. Even slight disturbances of this delicate system will cause significant climate changes, especially for NW Europe. While the current hydrographical situation and associated overflow pathways are well-documented, paleoceanographic studies of the Greenland and Faroe/Shetland (F/S) overflow pathways are still scarce. The F/S pathway is presently the subject of study of the MAST program (ENAM project). This project focusses on the late Quaternary overflow history of the important East Greenland pathway. High resolution multichannel sleevegun seismic data recently collected by the Geological Survey of Greenland and Denmark (GEUS) allowed identification of suitable box- and piston-coring sites. Results from the high-resolution cores, allowing direct correlation with regional atmospheric changes documented in the Greenland ice-cores will provide new information on causes and mechanisms of climate change. The continental slope and rise off SE-Greenland can be considered as a potential key area for paleoceanographic and paleoclimatic studies, since: 1) The area is located in the immediate vicinity of the Denmark Strait arctic gateway for water mass exchange between the Arctic and Atlantic ocean. Recent hydrographic measurements (Dickson 1994) demonstrate the important role of the area with regard to hydrographic processes contributing to the formation of NADW. 2) The seafloor morphology and information from multichannel seismic recording shows the presence of numerous large detached sediment drifts and other drift-related features, which will provide important paleoceanographic information as outlined before. 3) The distribution and architecture of the sediment drifts is also affected by down-slope processes transporting upperslope/shelf sediments of mainly glacial origin. Thus the area offers an unique opportunity to study the sediment drifts both with regard to the (paleo)oceanic flow regime and the climatically-inherited signal from the down-slope sediment input. Research activities: All research is directed towards documentation of high resolution natural climate variability during the late Quaternary. Separate topics include: 1. Seismic/sidescan sonar studies 2. High resolution quantitative micropaleontology (planktonic/benthic foraminifera, diatoms, calcareous nannoplankton, dinoflagellates) 3. High resolution stable oxygen/carbon isotope studies 4. DNA studies on planktonic foraminifera (with University of Edinburgh)

During 2000, observations under the framework of control of radioactive contamination were continued at 34 sites of the State System of Radiation Monitoring in the Russian Arctic. At all stations, daily monitoring of exposure dose strength of gamma emissions, and daily sampling of radioactive fallout from the atmosphere to determine total beta-activity are conducted. At sites in Arkhangelsk, Naryan-Mar, Salekhard, Murmansk, Dikson Island, Zhelaniya Cape, Kheis Island and Kandalaksha, sampling of atmospheric aerosols and precipitation was performed for specific radioisotopic analysis, including determination of tritium. Samples of surface water for determination of levels of 90-Sr and tritium were collected at radioactive contamination control stations in the mouth regions of the largest rivers of the Russian Arctic (Severnaya Dvina, Pechora, Mezen, Ob, Yenisey, Khatanga, Indigirka). 26 samples were collected for this purposes in 2000. Samples for determination of 90-Sr in seawater were collected at relevant sites in the Barents Sea and White Sea.

The 'Karex - Pechora' expedition marine investigations by the research vessel 'Ivan Petrov' in the Kara and Pechora seas in August 2000, and by the research vessel 'Hydrolog' during September-October 2000. During August 2000 samples of marine water, suspended and bottom sediments at 30 oceanographic stations were analyses for contaminants. At 8 stations, hydrobiological investigations included sampling of benthic organisms, plankton and fish, for studies of bioaccumulation and transformation of contaminants.

The 'Lena-2000' expedition was performed in the area of the mouth of the Lena river and the shelf of the eastern part of the Laptev Sea during August 2000. Samples of river and marine water, suspended and bottom sediments were taken at 30 hydrological stations to study the mechanisms of contaminant transport by river water.

The expedition by vessel 'Nikolai Kolomeets'included sampling of marine water, bottom sediments, benthos and plankton for studies of accumulation and transformation of OCs and estimation of related toxic effects on aqueous biocenoses. The marine studies took place during the period July-October 2000 in areas of the Pechora, Kara, Laptev, East-Siberian and Chukchi Seas.

The expedition 'Arctic-2000' included climatic, hydrometeorological and hydrochemical studies in the eastern part of the Central Arctic Basin, during the period July-August 2000.

Brief: Assessment of the significance of aquatic food chains as a pathways of exposure of indigenous peoples to PTS, assessment of the relative importance of local and distant sources, and the role of atmospheric and riverine transport of PTS in Northern Russia. Project rationale and objectives: (1) To assess levels of Persistent Toxic Substances (PTS) in the environment in selected areas of the Russian North, their biomagnification in aquatic and terrestrial food chains, and contamination of traditional (country) foods that are important components of the diet of indigenous peoples. (2) To assess exposure of indigenous peoples in the Russian North to PTS, and the human health impacts of pollution from local and remote sources, as a basis for actions to reduce the risks associated with these exposures. (3) To inform indigenous peoples about contamination by PTS of their environment and traditional food sources, and empower them to take appropriate remedial actions to reduce health risks. (4) To enhance the position of the Russian Federation in international negotiations to reduce the use of PTS, and to empower the Russian Association of Indigenous Peoples of the North (RAIPON) to participate actively and fully in these negotiations. Project activities to achieve outcomes: (1) Inventory of local pollution sources in the vicinities of selected indigenous communities. (2) Survey of levels and fluxes of PTS in riverine and coastal marine environment important for indigenous peoples living in these environments and using them for their subsistence; and assessment of fluxes of PTS to these environments via selected rivers and the atmosphere. (3) Dietary surveys of selected indigenous communities. (4) Study of biomagnification, based on measurements of selected PTS in representative species in food chains important for the traditional diet of indigenous populations. (5) Survey and comparative assessment of pollution levels of the indigenous and general population in selected areas. (6) Dissemination of results to all relevant stakeholders.

White whale (Delphinapterus leucas) blubber samples from three of the five different Alaskan stocks - Cook Inlet (n = 20), Eastern Chukchi Sea (n = 19) and Eastern Beaufort Sea (n = 2) - were analyzed for levels and patterns of chemical contaminants. Blubber of these whales contained sum PCBs, sum DDTs, sum chlordanes, HCB, dieldrin, mirex, *toxaphene and *HCH, generally in concentration ranges similar to those found in white whales from the Canadian Arctic and lower than those in white whales from the highly contaminated St. Lawrence River. The males of the Cook Inlet and Eastern Chukchi Sea stocks had higher mean concentrations of all contaminant groups than did the females of the same stock, a result attributable to the transfer of these organochlorine contaminants (OCs) from the mother to the calf during pregnancy and during lactation following birth. Principal components analysis of patterns of contaminants present in blubber showed that Cook Inlet stock appeared to have identifiable contaminant patterns that allowed the stock to be distinguished from the others. Our results also showed that blubber from the three Alaskan stocks was a source of contaminant exposure for human subsistence consumers, but the health risks from consumption are currently unknown.