The study of vegetation history and climate changes in the eastern subtropical Taiwan


The late Holocene environmental research is a key to understand the relation between human activities and climate changes, and the culture evolution always have strong correlation with climate fluctuations, like drought or flood events. Historical literature and archeological relics provide valuable insights into climate-caused disasters and their responses in human activities, like migration or alternation of agriculture types.
The high resolution lacustrine sediment is one of the most important materials to study the paleoenvironment and the climate changes. The analysis of the pollen in the sediment can supply the detail vegetation cover and inferred the climate conditions. The component of the pollen in the sediment can transfer quantitatively to the temperature or the precipitation by using the semi-quantitative or quantitative statistic techniques. In order to supply the objective and comprehensive environmental information, the strategies of multi-lakes were adopted in the recent studies of lake sediment.
The pollen analysis allows the reconstruction of vegetational changes and shifts of the complete vegetation zones. Furthermore, it is also possible to illustrate past plant diversity, stability and dynamic of ecosystems. Due to the strong relationship between vegetation and climate, the identification of past vegetational changes allow to reconstruct climate variability in the past. The quality of interpretations made by the pollen analysis is dependent upon a good understanding of the relationship between modern vegetation and modern pollen rain. The documentation of modern pollen rain contributed greatly to refining paleoclimatic interpretations of similar ecosystems.
For this, a study on the analyses of pollen from three lacustrine sediment cores was proposed, namely LYHL-B core taken from Liyu Lake of Hualien County, DH-7B core taken from the Dahu Lake of Iland County and TF-2 core taken from the Tsuifong Lake of Iland County. The results of these two lake sediment core will compare with the results of the sediment core, LYHL-B to understand the possible model of climate changes and the role of the eastern subtropical Taiwan in the global climate system in late Holocene.