碩士 / 國立彰化師範大學 / 生物學系 / 94 / Abstract
The Ilan Plain is situated at northeastern Taiwan. The climate was strongly influenced by the East Asian monsoon. In order to investigate the variation characteristics of the system, a lake sediment core named as SLP-D (30.76m)was collected form Shuang- Lien- Pi, at northwest of Ilan Plain (24°45’50’’ N; 121°37’55’’ E). From paleomagnetic analysis, the core was regarded to be able to support the paleoenvironment change information from 16 kyr B.P. to present. The study was in detail about the paleo-climate changes at the area studied, fossil diatom was employed in this study. The study indicate that the diatom abundance fluctuated between 0 and 3x108 vales/g DW, and the average was 0.31x108 vales/g DW. In addition, it was formed that the fossil diatom absolute abundance increased rapidly in seven periods, 13.6 kyr B.P.、12- 10 kyr B.P.、8.8 kyr B.P.、8- 6 kyr B.P.、 4.2- 2.4 kyr B.P. 、2- 1.6 kyr B.P. and 1.2- 0 kyr B.P, which indicated high primary productivity, and might also reflect a stronger monsoon event. Furthermore, according to the results of principal composition analysis, the first principal component ( PC1) could reflect the fluctuation of the lake level, and the second principal component (PC2) reflect an eutrophic condition. Based on the fossil diatom assemblage, high planktonic assemblage abundance generally reflects a high lake level and responds a moist climate condition. However, according to the fluctuation of eutrophic assemblage abundance, the Shuang- Lien- Pi might be a mesotrophic or an oligtrophic lake since 16 kyr B.P., except at the periods of 12- 10kyr B.P. and 0- 1 kyr B.P. showed an eutrophic condition.
| Identifer | oai:union.ndltd.org:TW/094NCUE5112005 |
| Date | January 2006 |
| Creators | Ping Hsu, 徐冰 |
| Contributors | Wei-Lung Wang, 王瑋龍 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 69 |
Page generated in 0.0017 seconds