Temporal controls on silicic acid utilisation along the West Antarctic Peninsula

The impact of climatic change along the Antarctica Peninsula has been widely debated in light of atmospheric/oceanic warming and increases in glacial melt over the past half century. Particular concern exists over the impact of these changes on marine ecosystems, not only on primary producers but also on higher trophic levels. Here we present a record detailing the historical controls on the biogeochemical cycling of silicic acid [Si(OH)4] on the west Antarctica Peninsula margin, a region in which the modern phytoplankton environment is constrained by seasonal sea-ice. We demonstrate that Si(OH)4 cycling through the Holocene alternates between being primarily regulated by sea-ice or glacial discharge from the surrounding grounded ice-sheet. With further climate-driven change and melting forecast for the 21st Century, our findings document the potential for biogeochemical cycling and multi-trophic interactions along the peninsula to be increasingly regulated by glacial discharge, altering food-web interactions

Lake Baikal diatom taxonomy workshop

Following a welcome to the ECRC, Rick Battarbee went on to stress the importance of quality assurance in environmental science. It is a fundamental principle of science that results are reproducible. Standardisation of methods is an important element in achieving this objective. Water chemistry has long practised analytical quality control (fa.QC) within and between laboratories. For biology, taxonomic quality control (TOC) is more recent but an equally important issue, especially in international studies involving shared material. This is particularly true for Lake Baikal diatom studies where teams in the US, Russia, UK, Japan and others are working on major projects based en diatom remains in long and short sediment cores. This vvorkshop marks the first real attempt to introduce taxonomic control into these prcjects

The deposition and accumulation of endemic planktonic diatoms in the sediments of Lake Baikal & an evaluation of their potential role in climate reconstruction during the Holocene

Planktonic diatoms play a central role in studies of Lake Baikal. Not only are they dominant primary producers in the lake's food chain, but (i) the exceptionally long, lake sediment records are diatom rich, and (ii) many of the taxa are endemic which makes them of interest for evolution studies. In this study we have collaborated with Swiss and Russian scientists and the wider BICER (Baikal International Centre for Ecological Research) community to develop an understanding of the relationships between diatom production and life-cycle strategies, diatom sedimentation in the water column, and diatom preservation and accumulation in sediment records. Our primary aim has been to explore, using quantitative techniques, the potential and limitations of diatoms as indicators of past environmental change in the sediment record