Sylvi Haldorsen

The thermal springs of Bockfjord, Svalbard : Occurrence and major ion hydrochemistry

The Troll and Jotun thermal springs of northern Svalbard, with temperatures of up to 25.6°C, are derived from a major fault forming the junction between Devonian sandstones and Proterozoic marbles, mica schists and gneisses. The Troll waters are dominated by Na–HCO3 compositions and the Jotun waters by Na–Cl compositions. The pristine thermal water source has a sub-neutral pH and is highly reducing. Taken at face value, common geothermometers suggest temperatures at depth of 130–180°C for the Troll springs (corresponding to a depth of 1.6–2.3 km), with 10–30% thermal water diluted by 70–90% cold water. Such geothermometers may, however, be inappropriate to the cool, high CO2 waters of Bockfjord, and real temperatures at depth and dilution factors are probably considerably lower. The salinity of the thermal water appears to be only partially derived from water–rock interaction; Br\Cl ratios suggest that seawater or possibly evaporites may be a source of chloride salinity.

The thermal springs of Bockfjorden, Svalbard: II: selected aspects of trace element hydrochemistry

Waters from the Trollkjeldene (Troll springs) and Jotunkjeldene (Jotun springs) thermal springs on northern Svalbard have been analysed by ICP-AES, ICP-MS and IC techniques for a wide range of major and trace elements. Although it is plausible that the thermal waters originate from a deep reservoir in siliceous rocks, it appears that a significant component of their hydrochemical signature is derived from dissolution of higher-level Hecla Hoek marbles. Rare earth elements (REEs) show some degree of enrichment of heavy REEs in the water phase, relative to the marbles and to the travertines that precipitate from the waters. A strong positive Eu anomaly is also observed in the waters, suggesting preferential mobilisation of Eu under reducing conditions. The ratio Nb/Ta is rather well-preserved between the marbles, the waters and the travertines.

The water balance of an arctic lake and its dependence on climate change: Tvillingvatnet in Ny-Ålesund, Svalbard

Lake Tvillingvatnet is the water supply to the arctic research settlement Ny-Ålesund in Svalbard. In the period 1920-1930 it was observed that the lake received groundwater from a sandstone-aquifer underlying the lake. Recent water balance studies indicate that there is no longer any groundwater flow of that type into the lake. This change can be explained by a warmer climate resulting in a fast retreat of the glaciers after the Little Ice Age. Large amounts of melt water combined with a steep hydraulic gradient may have caused partial melting of permafrost along the front of the Brøggerbreen Glacier, which was situated c . 0.5 km west of Lake Tvillingvatnet at that time. Today, the glacier front is more than a kilometre SW of the lake. The formation of new permafrost has resulted in freezing of the previously active groundwater outflow channels. The present flow of water into Tvillingvatnet during the autumn is probably due to shallow groundwater in the active layer along the talus of the Zeppelinfjellet Mountain.

Can Triticum urartu (Poaceae) be identified by pollen analysis? Implications for detecting the ancestor of the extinct two-grained einkorn-like wheat.

The domestication of the one-grained einkorn (Triticum monococcum) in the Near East is relatively well known. However, an independent two-grained einkorn-like domestication has been archaeobotanically detected and scarce information is available. Triticum urartu, a wild wheat, was not fully described until the 1970s because the phenology does not allow it to be distinguished easily from wild einkorn (Triticum boeoticum subsp. thaoudar), although a genetic separation exists. Both species are mostly two grained and could potentially be the relatives of the extinct two-grained form. Pollen grains of several genetically well-identified wheat species, including T. urartu and T. boeoticum subsp. thaoudar, were studied by measuring the grain diameter and examining the exine sculpturing with phase-contrast microscopy and scanning electron microscopy to gain an insight into differences enabling taxonomic identification. This work showed that, although T. urartu pollen is smaller on average, grain diameter is not sufficient because of the size overlap between the species, but T. urartu presents a different exine sculpturing (scabrate) from other Triticum spp. (aerolate). This outcome is useful for taxonomists and archaeobotanists. First, it will allow a simple re-classification of herbarium materials. Second, further research could establish whether T. urartu was cultivated.

BASELINE GROUNDWATER QUALITY IN THE COASTAL AQUIFER OF ST. LUCIA, SOUTH AFRICA

A study of baseline groundwater chemistry has been carried out in the pristine areas around Eastern Shores, Lake St Lucia, North-eastern South Africa. The study aims to provide a quality baseline against which anthropogenic (urban) impacts elsewhere may be evaluated. In general, groundwater in the Eastern Shores region is of low conductivity, and a vital freshwater source to both Eastern Shores and Lake St Lucia itself. Two distinct groundwater types are recognized in the aquifer, one dominated by sodium and chloride and the other by calcium and bicarbonate. The two are spatially distinct, corresponding to separate groundwater mounds. Variation in electrical conductivity is thought to be related to evapotranspiration. The study provides valuable background data on coastal aquifer natural quality and a suitable baseline to judge impacts upon that aquifer, both from historic and future urbanization.

Ecology and Conservation of Estuarine Ecosystems: Acknowledgements

List of contributors Foreword Alan Whitfield Preface 1. South Africas first World Heritage Site Roger N. Porter 2. Management history Ricky H. Taylor 3. Geological history Greg A. Botha, Sylvi Haldorsen and Naomi Porat 4. The marine environment Allan D. Connell and Sean N. Porter 5. Catchment hydrology Derek D. Stretch and Andrew Z. Maro 6. The Wetlands William N. Ellery, Suzanne E. Grenfell, Michael C. Grenfell, Marc S. Humphries and Kirsten B. Barnes 7. Estuary and lake hydrodynamics Derek D. Stretch, Clint P. Chrystal, Robynne A. Chrystal, Christopher Maine and Justin J. Pringle 8. Groundwater hydrology Bruce E. Kelbe, Ricky H. Taylor and Sylvi Haldorsen 9. Physico-chemical environment Renzo Perissinotto, Nicola K. Carrasco and Ricky H. Taylor 10. Microalgae Renzo Perissinotto, Guy C. Bate and David G. Muir 11. Macrophytes Janine B. Adams, Sibulele Nondoda and Ricky H. Taylor 12. Benthic invertebrates Deena Pillay, Sarah J. Bownes and Holly A. Nel 13. Zooplankton Nicola K. Carrasco, Renzo Perissinotto and Hendrik L. Jerling 14. Penaeid prawns Anthony T. Forbes and Nicolette T. Forbes 15. Fish and fisheries Digby Cyrus 16. Birds Jane Turpie, Ricky H. Taylor, Meyrick Bowker and Caroline Fox 17. Crocodiles Xander Combrink, Jonathan Warner and Colleen T. Downs 18. Hippopotamuses Ricky H. Taylor 19. Alien and invasive species Nelson A. F. Miranda and Janine B. Adams 20. Food webs and ecosystem functioning Ursula M. Scharler and Fiona C. MacKay 21. Climate change impacts Andrew A. Mather, Derek D. Stretch and Andrew Z. Maro References Appendix: web page database, 1900-2010 Nuette Gordon Index.