Epiphytic Diatoms from the Arctic Coasts, RIS ID 6175

Diatoms are important biotic elements of Arctic marine ecosystem, significantly influencing the dynamics of primary production, nutrient cycling, carbon transport, oxygen flow and its activity, and all trophic processes. It is therefore imperative for the sake of the future of Arctic marine ecosystems to thoroughly investigate and well understand the ecology, taxonomy and biogeography of these microalgae. Diatoms are reported to be excellent ecological indicators. They have been used for paleoenvironmenta l reconstructions as well as for assessment of the recent water bodies ecological status. In the light of rapid climate change and global warming, Arctic research has never been more important than it is today. While ecological preferences of some common diatom species from lower latitudes are relatively well known, the present state of our knowledge of the autecology of modern Arctic diatom taxa disables us from using the diatom communities to interpret recent changes or foresee possible anomalies in the Arctic marine ecosystem. Although, microalgae (including diatoms) have been long collected from the Arctic, many habitats and geographical areas have been at best poorly explored. Moreover, most studies on Arctic marine diatoms have dealt with planktonic , ice-associated or benthic species found in the sediment cores. Little is known about the epiphytes regarding either their ecology or taxonomy, or species relative abundance, though existing reports indicate that these microalgae may be the most importan t primary producers at certain times of the year. In the framework of our project thalli of various macroalgal species will be collected from selected Arctic localities and associated diatom communities will by studied with SEM. Proposed method will allow for investigating epiphytic diatoms in undisturbed and almost unchanged conditions. To our knowledge, this study will be the first detailed SEM-based analysis of marine epiphytic diatoms from the Arctic region.