A REVIEW OF DIATOM PALAEOECOLOGICAL STUDIES IN COAST SHELF REGION

Previous studies of diatoms in continental shelf and coast areas are reviewed in this paper, which include the modern ecological group classification of diatoms, the eutrophication of coastal diatoms in last century, and the studies in Quaternary diatom assemblages within China and abroad. In addition, the problems encountered in the research are especially discussed. Due to the strong hydrodynamic processes and complex depositional environment in the coastal and shelf regions, the diatom preservation potential is one of the most important factors to be considered. The diatom preservation potential is mainly constrained by fragmentation and dissolution. In the future, interdisciplinary studies together with biomarkers and molecule sequencing should be carried out. Concerning the application of transfer functions in the diatom palaeoecological studies, there are many arguments and questions. The linear response of diatom assemblage to environmental variables is in dispute, and the assumption that the diatom ecological responses to the environmental variables have nothing to do with time and space is in doubt. Attention is required when the transfer function is used, and the multi-proxy synthesis will make the paleoenvironmental reconstructions more credible.