Dendroclimatological Study on the Natural Taiwan Spruce (Picea morrisonicola) in Ta-Ta-Chia Area of Central Taiwan
| Autor: | Ming-Chun Jane, 詹明勳 |
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| Rok vydání: | 1999 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 87 The purpose of this study was to establish an information the fundamental dendroclimatology of Taiwan spruce distrbuted in the Ta-Ta-Chia area of central Taiwan. Firstly, micro anatomical structure of cambium division activities of wood was observed. According to the sampls taken on May 5th,1999, cambium has begun to divide. Secondly, Taiwan spruce density boundary of early-wood and late-wood was 560 kg/m3 determined by soft x-ray micro-densitometry method. Chronology of eight tree-ring characteristics chronology was established from cores analyzed by tree-ring analysis program. According to dendroclimatological results indicated that tree-ring width parameters responded to spring temperatures, fall temperature, summer precipitation, and fall precipitation of current growth season. However, tree-ring density parameters responded to summer temperature of current growth season and weak correlation or negative correlation show to the precipitation. The tree-ring density parameters of different elevation areas did not respond to precipitation of different month significantly, that is, the elevation gradient had no significant relationship to the change of environment; so did the parameters to monthly precipitation. The results also shown that tree-ring density was significantly affected by monthly temperature more than that of monthly precipitation. In the past 245 years, reconstructed average temperature of the site shown that it was cool during 1835-1840 and change to warm during 1845-1850. During 1850-1870 and 1890-1930, the temperature was stable, but during it was cool during 1810-1890 and 1930-1950. Then, temperature increased after 1950. Meanwhile, the change of summer and autumn precipitation were short at the beginning of 19th and 20th centuries, then it turn to humid after 1940. However, it decreased again after 1990. In analysis of the correlation coefficients between actual indices and predicted indices of tree-ring width in different elevation area, the correlation coefficients (0.50-0.55) of the tree-ring indices affected by typhoon of 26 years was lower than those (0.81-085) without typhoon affect of 16 years. The results indicated that the disturbance of typhoon would reduce the fixation of regular climatic factors. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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