Abstract
The Iceland Basin region of the N. Atlantic is important for two reasons. Firstly, the biological carbon pump here exhibits one of the strongest signals of any of the worlds oceans. Secondly, the food-web of this region supports the important herbivorous calanoid copepod, Calanus finmarchicus, that forms an important dietary component of the commercially important juvenile Cod stock. Both carbon export via the biological carbon pump and the transfer of energy to herbivorous zooplankton depends primarily on the amount of nitrate-based new production relative to total primary production. However, climate change scenarios for this region predict that ocean stratification may become stronger, and as a consequence, the upward flux of nitrate may become constrained. Furthermore, there are some recent indications that new nitrate-based production in this region may be somewhat iron limited. To test these ideas, we therefore undertook a cruise to the Iceland Basin region in July / August 2007, to examine controls on new production. We undertook measurements of phytoplankton new and regenerated production using 15N-NO3, 15N-NH4 and 13C tracers and we compared nitrate uptake with the upward diffusive flux of nitrate determined from turbulence measurements. We also assessed phytoplankton new production rates in response to ambient light and Fe gradients and further assessed Redfield C:N fixation rates from duallabelling (13C, 15N) experiments since the Redfield stoichiometry of particle flux has important consequences for relative rates of carbon and nitrogen export. In this paper, we report on some of our key findings.

Abstract
Barrier sandbars and barrier islands are geologically young, highly dynamic and represent a complex coastal system that includes a number of different but closely related sedimentary depositional environments with geomorphologic elements of varying origin, genesis and evolution. Barrier sandbars are exposed ridges of sand that are built offshore by wave action. The so-called Kniepsand on the island of Amrum represents one of the widest beaches in Europe. The Kniepsand originally belongs to a system of sandbars lining the North-Frisian coast. Some of these sandbars are already attached to the mainland (e.g. St. Peter-Ording-Sand and Westerhever-Sand). The offshore sandbars of Japsand, Norderoogsand and Suderoogsand are located in front of the western coastline of the North-Frisian Island and the Halligen and fulfil the function of natural coastal defence dissipating the energy of the incoming deep-water waves of the North Sea. Barrier sandbars are usually investigated through the use of aerial photos and borehole data. Therefore, the processes of evolution and the internal structure of sandbars are often unknown. That is why this study chooses an integrated approach using high-resolution ground-penetrating radar (GPR) and sedimentological analyses of shallow sediment cores drilled at selected sites along the radar profiles. A geophysical Survey Systems Inc. radar system, SIR-2000 coupled with a 200 MHz antenna, was used. Based on these data a sedimentary model was generated that describes the process of barrier sandbar migration and the attachment to the Pleistocene island core. According to historical maps and nautical charts of the sixteenth and seventeenth century, the Kniepsand used to be a solitary barrier sandbar located well in front of the islands west coast without any connection to its Pleistocene core consisting of Saalian moraine deposits. The presented model shows how the Kniepsand has welded onto the Pleistocene island core of Amrum. Before the barrier sandbar was connected to the island, tidal flat deposits had been accumulated in a low energy environment. Tidal flat deposits show a general coarsening upward trend and turn into overlying coarser grained beach deposits. Old cliffs formed through several storm surges are also preserved in GPR data. Normally, the former structure of the barrier sandbar will be lost as its sediment is welded onto the island core to form the contemporary sandy beach. The study indicates that GPR-data make it possible to reveal the structure of the former sandbar and to figure out and understand the barrier sandbar attachment process.

Abstract
It is not possible to derive reliable fishing mortality estimates for the majority of species that are potentially impacted by the trawl fishery from landings data alone. For some species the proportion of the catch that is landed is driven by market forces so that fluctuations in annual landings do not necessarily reflect fluctuations in actual catches or in abundance, whereas many species are not commercially useful and are not landed at all. Although the total annual catch of such species is not known, trends in the trawl survey abundance indices can be used as indicators of the impact of incidental mortality on their populations. The trend in abundance indices for 1985 to 2008 are presented for 100 bycatch species (or species groups) taken during research trawl surveys of the west and south coasts of South Africa. For many species the inter-annual fluctuations are greater than any apparent trend. Trend lines for the majority of species do not have significant slopes.

Abstract
One predicted result of climate change on upwelling systems is that increasing pressure gradients between land and sea will result in greater equatorward wind stress and therefore increased upwelling intensity. Notable ecosystem changes have been documented in eastern boundary upwelling regions in recent decades, including the southern Benguela, where striking changes in zooplankton, pelagic, demersal, line, squid and rock lobster fisheries and seabird abundances have been shown. Nutrient availability has undeniable bottom- up influences on trophic structure and food-web pathways by mediating phytoplankton competition and succession. In this first long-term study of nutrient variability in the Benguela system, we compiled and interrogated historical nutrient, oxygen and hydrographic data from a defined geographic area incorporating St Helena Bay. General linear models (GLMs) were applied to archived nutrient data to establish longterm concentration trends where seasonal effects are excluded. Surface concentrations were also excluded as these are modified by phytoplankton productivity. Nitrate and phosphate concentrations both increased between 1983 and 2004 by ~40% and ~50% respectively, while silicate showed no trend over this period. Oxygen concentrations declined by ~30% between 1960 and 2004. The prominent increases in nitrate and phosphate, together with decreasing oxygen concentrations, suggest a parallel increase in primary (new) productivity, leading to elevated POC/N flux and later decomposition processes that utilize oxygen below the pycnocline. Both processes have important future implications for biogeochemical cycles, ecosystems and commercial fisheries that we discuss here. Furthermore, due to the retention of upwelled water and biogenic material in St Helena Bay, the region could provide early indicators of change.

Abstract
Estuarine research in South Africa has generally been ?graduation driven? in that short datasets (<3 years) are mostly collected to answer highly defined questions normally for degree purposes. The SAEON Elwandle node aims to implement a long-term study examining the demersal fish communities of three estuaries with differing freshwater input (Kariega Estuary ? marine dominated, Great Fish Estuary ? freshwater dominated and Sundays Estuary ? intermediate freshwater input). The long-term nature of the study should allow for temporal variation on both the annual and seasonal scales to be investigated and the role that freshwater plays within these systems to be further established. As the selected systems have vastly different turbidity levels, gear avoidance may be an issue in clear water systems such as the Kariega. A pilot study has been initiated where comparative otter trawling for demersal fish was undertaken during the day and night at 15 sites in the Kariega Estuary over a period of three consecutive days in Spring 2007. A total of 1961 fishes representing 28 species from 15 families were recorded. Catches were dominated by Glossogobius callidus, Rhabdosargus holubi, Solea turbynei, Caffrogobius gilchristi and Heteromycteris capensis. Glossogobius callidus, S. turbynei and C. gilchristi were recorded in significantly higher numbers at night than during the day (p < 0.05). In contrast only one species, R. holubi, was caught in significantly higher numbers during the day (p < 0.05). The total number of species and individuals sampled was also significantly higher at night (p < 0.05). Initial results indicate that sampling would be more suitable at night but further investigation in the turbid Great Fish Estuary is required.