Thiede et al.: Dynamics and History ofthe Laptev Sea and its Continental Hinterland
707
and spatial variations in active layer hydrological and thermal processes and solute fluxes were
quantified and compared with climatological data. A complete spring to autumn record of water
and sediment discharge by streams entering Levinson-Lessing Lake and of the sedimentation in
the lake, was measured in order to get an impression of the seasonal dynamic processes of
sediment transport and accumulation under the present environmental and climatic conditions.
The representative field data were put into a wider context by landscape mapping and
subsequent connection with remote sensing data from Landsat TM images in order to
extrapolate the field data to larger areas.
The results discussed in this book were obtained in the catchment of the Levinson-Lessing
Lake. Mapping of vegetation, soils, and geomorphology in the field, supported by
interpretations of air photos, enabled Anisimov and Pospelov (this volume) to classify 34
landscape units. Surface hydrological investigations were carried out by Zimichev et al. (this
volume). They quantified seasonal fluxes of water and sediment for a typical high Arctic-nival
streamflow regime entering the Levinson-Lessing Lake. The temporal dynamic of water, heat,
and solute fluxes in the active layer was studied for a complete freeze-thaw cycle by Boike and
Overduin (this volume) using Time Domain Reflectometry. The results indicate that the
dominant heat sinks during spring and summer are the sensible and latent heat fluxes into the
atmosphere. The soil heterogeneity strongly impacted hydrologic and thermal processes in the
active layer.
The role of permafrost affected soils as sinks or sources of carbon is determined by labile
balance between the production and the decay of organic matter. The relationship between the
carbon-cycle and soil substrate, hydrological and thermal regime of the active layer, vegetation,
and relief, was studied at different polygonal tundra sites. Seasonal trace gas emission of CH4
and C02 was quantified (Sommerkorn et aI., this volume) and, using carbon isotopes, the
recent decomposition processes of carbon in permafrost-affected soils were studied (Samarkin
et aI., this volume). Such data are important for the understanding of soil generation and carbon
accumulation processes in the present and past and thus for knowledge about the development
of the Siberian Tundra.
Environmental history of the permafrost landscape
The development of permafrost is a characteristic process in non-glaciated regions with cold,
continental climate. The deposits formed in permafrost landscapes contain complex information
concerning the regional and local environmental conditions of the time of sediment accumulation
and freezing. Besides chronological, sedimentological, mineralogical, geochemical, and
paleontological data, specific information can be obtained from the cryostructure of syngenetic
permafrost sequences as well as the kind and composition of ground ice bodies.
Widely continuous permafrost development takes place in lowland areas where accumulation
distinctly exceeds denudation and where sufficient moisture leads to well expressed ground ice
formation. Investigations of permafrost sequences in the Taymyr region, therefore, have
focused on the Taymyr lowland being bordered by the Putoran Plateau to the south and the
Byrranga Mountains to the north. Early work in the western and southwestern lowland had
supplied first important information concerning the climatic history and paleogeography of the
region (e.g., Karpov, 1986; Tumel, 1985). On the central and northern lowland, in contrast,
permafrost data were restricted to some geothermic measurements in boreholes. The latter areas,
therefore, were the major focus for permafrost investigations within the scope of the Taymyr
Project. Special attention was drawn to the surroundings of the Labaz Lake, to Cape Sabler at
the western shore of the Taymyr Lake, and to the western rim of the Putoran Plateau, where
running work was continued. Additional information was obtained from paleogeographic,
707
and spatial variations in active layer hydrological and thermal processes and solute fluxes were
quantified and compared with climatological data. A complete spring to autumn record of water
and sediment discharge by streams entering Levinson-Lessing Lake and of the sedimentation in
the lake, was measured in order to get an impression of the seasonal dynamic processes of
sediment transport and accumulation under the present environmental and climatic conditions.
The representative field data were put into a wider context by landscape mapping and
subsequent connection with remote sensing data from Landsat TM images in order to
extrapolate the field data to larger areas.
The results discussed in this book were obtained in the catchment of the Levinson-Lessing
Lake. Mapping of vegetation, soils, and geomorphology in the field, supported by
interpretations of air photos, enabled Anisimov and Pospelov (this volume) to classify 34
landscape units. Surface hydrological investigations were carried out by Zimichev et al. (this
volume). They quantified seasonal fluxes of water and sediment for a typical high Arctic-nival
streamflow regime entering the Levinson-Lessing Lake. The temporal dynamic of water, heat,
and solute fluxes in the active layer was studied for a complete freeze-thaw cycle by Boike and
Overduin (this volume) using Time Domain Reflectometry. The results indicate that the
dominant heat sinks during spring and summer are the sensible and latent heat fluxes into the
atmosphere. The soil heterogeneity strongly impacted hydrologic and thermal processes in the
active layer.
The role of permafrost affected soils as sinks or sources of carbon is determined by labile
balance between the production and the decay of organic matter. The relationship between the
carbon-cycle and soil substrate, hydrological and thermal regime of the active layer, vegetation,
and relief, was studied at different polygonal tundra sites. Seasonal trace gas emission of CH4
and C02 was quantified (Sommerkorn et aI., this volume) and, using carbon isotopes, the
recent decomposition processes of carbon in permafrost-affected soils were studied (Samarkin
et aI., this volume). Such data are important for the understanding of soil generation and carbon
accumulation processes in the present and past and thus for knowledge about the development
of the Siberian Tundra.
Environmental history of the permafrost landscape
The development of permafrost is a characteristic process in non-glaciated regions with cold,
continental climate. The deposits formed in permafrost landscapes contain complex information
concerning the regional and local environmental conditions of the time of sediment accumulation
and freezing. Besides chronological, sedimentological, mineralogical, geochemical, and
paleontological data, specific information can be obtained from the cryostructure of syngenetic
permafrost sequences as well as the kind and composition of ground ice bodies.
Widely continuous permafrost development takes place in lowland areas where accumulation
distinctly exceeds denudation and where sufficient moisture leads to well expressed ground ice
formation. Investigations of permafrost sequences in the Taymyr region, therefore, have
focused on the Taymyr lowland being bordered by the Putoran Plateau to the south and the
Byrranga Mountains to the north. Early work in the western and southwestern lowland had
supplied first important information concerning the climatic history and paleogeography of the
region (e.g., Karpov, 1986; Tumel, 1985). On the central and northern lowland, in contrast,
permafrost data were restricted to some geothermic measurements in boreholes. The latter areas,
therefore, were the major focus for permafrost investigations within the scope of the Taymyr
Project. Special attention was drawn to the surroundings of the Labaz Lake, to Cape Sabler at
the western shore of the Taymyr Lake, and to the western rim of the Putoran Plateau, where
running work was continued. Additional information was obtained from paleogeographic,