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Die Weltmeere sind der groste Lebensraum der Erde. Von den flachen Kustengewassern bis in die dunkle Tiefsee wird ihr Boden von einer immensen Vielfalt „exotischer“ Lebewesen, dem Benthos, besiedelt. Wissenschaftler bringen Licht in das Dunkel und Ordnung in die Mannigfaltigkeit. Sie untersuchen die Zusammensetzung der Lebensgemeinschaften und das Funktionieren der Okosysteme am Meeresboden, und sie erkunden die Folgen des Umweltwandels in diesem einzigartigen und noch kaum erforschten Lebensraum.

The distribution and structure of zoobenthic communities have been investigated in the northern North Atlantic. The principal goal of these studies is to assess the degree to which benthic community patterns depend on and/ or mediate carbon flux between the pelagic and benthic realms, as well as between seabed, sediment-water interface and benthic boundary layer. A common rationale is that these patterns integrate the impact of environmental factors over longer periods of time and reflect relatively long-lasting or predictably recurrent environmental states, thus providing clues to the relative significance of potential community determinants on a time scale of months to years. Since 1992, several meso-scale field studies have been carried out in three regions at the East Greenland continental margin between 68° N and 81° N at water depths ranging from 40 to 3,700 m. A suite of sampling methods was employed (corers, trawls, seabed imaging) to adequately probe various benthic community fractions, such as foraminifers, poriferans, macrobenthic endofauna, peracarid crustaceans and megabenthic epifauna.A depth zonation in the faunal composition, accompanied by a shift in the predominance of different feeding types and a significant decline in biomass and abundance by as much as two and three orders of magnitude was the most conspicuous general pattern detected. However, in terms of species richness, no common trend for water depth or latitude was perceivable. The general depth zonation of the macrobenthos as well as the spatial concordance of high macrobenthic abundance and biomass with relatively productive hydrographic zones, such as marginal ice zones, polynyas and anti-cyclonic gyres, provide evidence for the importance of water column processes and, hence, for subsequent food availability as major determinants for benthic assemblages and the significance of pelago -benthic coupling in the study area in general. However, for megafaunal species such as echinoderms, community patterns on a 10-1an scale and the dispersion of organisms on a 100-m scale, are best explained by seafloor properties. There is no evidence of direct pelago-benthic coupling, irrespective of water depth. These contrasting findings emphasize that the relative importance of potential community determinants can change with both spatial scale and life traits, e.g. body size, mobility and feeding ecology, of the organisms considered.

Russian and German scientists have investigated the extreme environmental system in and around the Laptev Sea in the Siberian Arctic. For the first time a major comprehensive research program combining the efforts of several projects addressed both oceanic and terrestrial processes, and their consequences for marine and terrestrial biota, landscape evolution as well as land-ocean interactions. The primary scientific goal of the multidisciplinary program was to decipher past climate variations and their impact on contemporary environmental changes. Extensive studies of the atmosphere, sea ice, water column, and sea-floor on the Laptev Sea Shelf, as well as of the vegetation, soil development, carbon cycle, permafrost behaviour and lake hydrology, and sedimentation on Taymyr Peninsula and Severnaya Zemlya Archipelago were performed during the past years under a framework of joint research activities. They included land and marine expeditions during spring (melting), summer (ice free), and autumn (freezing) seasons. The close bilateral cooperation between many institutions in Russia and Germany succeeded in drawing a picture of important processes shaping the marine and terrestrial environment in northern Central Siberia in Late Quaternary time. The success of the projects, which ended in late 1997, resulted in the definition and establishment of a new major research effort which will concentrate on establishing a better understanding of the paleoclimatic and paleoenvironmental record of the area. This is important because it allows to be able to judge rates and extremes of potential future environmental changes.