Upwelling events, coastal offshore exchange, links to biogeochemical processes - Highlights from the Baltic Sea Sciences Congress at Rostock University, Germany, 19-22 March 2007

The Baltic Sea Science Congress was held at Rostock University, Germany, from 19 to 22 March 2007. In the session entitled"Upwelling events, coastal offshore exchange, links to biogeochemical processes" 20 presentations were given,including 7 talks and 13 posters related to the theme of the session.This paper summarises new findings of the upwelling-related studies reported in the session. It deals with investigationsbased on the use of in situ and remote sensing measurements as well as numerical modelling tools. The biogeochemicalimplications of upwelling are also discussed.Our knowledge of the fine structure and dynamic considerations of upwelling has increased in recent decades with the advent ofhigh-resolution modern measurement techniques and modelling studies. The forcing and the overall structure, duration and intensity ofupwelling events are understood quite well. However, the quantification of related transports and the contribution to the overall mixingof upwelling requires further research. Furthermore, our knowledge of the links between upwelling and biogeochemical processes is stillincomplete. Numerical modelling has advanced to the extent that horizontal resolutions of c. 0.5 nautical miles can now be applied,which allows the complete spectrum of meso-scale features to be described. Even the development of filaments can be describedrealistically in comparison with high-resolution satellite data.But the effect of upwelling at a basin scale and possible changes under changing climatic conditions remain open questions

Evolution of Early and Middle Pleistocene river valley systems in Polish-Ukraine-Belarus cross-border areas based on geological and malacological proxies

The geological setting of the Bug-Pripyat interfluve and the close proximity of the source of the Pripyat River to the well-developed Middle Bug River valley suggest that these rivers may have been connected in the past. Analysis of geological cross-sections around the Polish-Ukraine-Belarus cross-border areas together with study of associated Pleistocene palaeoflora shows that buried alluvial deposits of the proto-Bug and proto-Pripyat clearly represent the Preglacial (MIS 103-23), Podlasian/Turskian-Donian/Brest Interglacial (Cromerian I-II; MIS 21-17) and the Mazovian/Likhvinian/Alexandrian Interglacial (Holsteinian; MIS 11c). Their elevated position in mid-eastern Poland suggests the possibility of accumulation by proto-Bug waters flowing eastwards, which determined the formation and development of the lower-lying proto-Pripyat valley system in northwestern Ukraine at those times. The occurrence of the Ponto-Caspian species Lithoglyphus naticoides (C. Pfeiffer, 1828), Borysthenia naticina (Menke, 1845) and Corbicula fluminalis (O.F. Müller, 1774) in the mollusc assemblages of the Mazovian/Likhvinian/Alexandrian Interglacial implies that the main watershed between the Baltic Sea and the Black Sea drainage basins might have been situated in the northern part of the area studied. Presumably its main part was drained by the waters of the proto-Bug catchment connected with the proto-Pripyat and flowing farther to the east towards the Dnieper River entering the Black Sea

Influence of coastal upwelling on chlorophyll a concentration in the surface water along the Polish coast of the Baltic Sea

Space-time variations in chlorophyll a (Chl a) concentrations in the surface water of upwelling regions along the Polish coast of the Baltic Sea were analysed. Carried out between 1998 and 2002 in the warmer season (from April till October), the measurements were targeted mainly at the Hel upwelling. Satellite-derived sea surface temperature (AVHRR) and Chl a data (SeaWiFS) were used. Generally speaking, the Chl a concentration increased in the upwelling plume, except along the Hel Peninsula, where two scenarios took place: a reduction in Chl a concentration in spring and an increase in autumn

Saccade Processing in Hemispatial Neglect

It has previously been reported, that the frontal lobe plays an important role in the inhibition of eye-movements and that patients with frontal lesions show increased problems in suppressing unwanted pro-saccades. Nevertheless, Butler et al. (2009) found evidence that patients with posterior lesions suffering from hemispatial neglect are also unable to perform correct anti-saccades. Here we investigated whether this deficit could be driven by an inhibition failure. We tested patients with hemispatial neglect after right hemisphere stroke in a pro-, anti-saccade and fixation task paradigm. For the anti-saccades, the neglect patients showed a bilateral impairment, in that they produced incorrect pro-saccades towards left and right stimuli. Pro-saccades could be executed but their accuracy was reduced especially towards left targets. In the fixation condition, patients showed an increased amount of false pro-saccades towards the right stimuli only. As previous argued the data support the interpretation that with a right stimulus, the neglect patients code the location accurately, but fail to suppress the right pro-saccade in favour of the leftward anti-saccade. For the left target it may be that the target location is not coded accurately in the first place (even pro-saccades fall short of the target) thus precluding vector inversion

Memory guided saccade processing in visual form agnosia.

No abstract available

Response inhibition in hemispatial neglect.

Patients with hemispatial neglect exhibit visuospatial impairments in the contralesional hemispace, failing to respond to items presented in their left space. Moreover, eye-movements into left space are abnormal with fewer, hypometric fixations and increased leftward latencies. Surprisingly we have recently found that, in an anti-saccade task (where a saccade away from a stimulus is required), neglect patient failed to suppress incorrect pro-saccades to both right and leftwardly presented targets (Rossit et al, 2009). What we could not establish was whether these bilateral impairments were due to a failure to locate the visual stimulus and reverse its location to specify the goal for the anti-saccade, or whether the patients suffered from an inability to suppress the pre-potent response. We therefore asked neglect patients to either perform pro-saccades (go) towards right and leftwardly presented stimuli or to inhibit their response and maintain central fixation (no-go). The percentage of go compared to no-go trials was varied systematically. We found that neglect patients showed no problems suppressing leftward saccades yet performed worse than control groups in suppressing rightward saccades over all conditions. This suggests that the, previously reported, involuntary leftward pro-saccade errors were not due to inhibition failure but that the rightward errors were