| Summary: | 碩士 === 國立屏東科技大學 === 森林系 === 91 === Leucaena lucocephalla invade into every different land use type very fast recently, and it had become a dominant in the part of woodland, L. lucocephalla has a character of alleopathy, it will inflect the biodiversity of woodland ecosystem. This study is for understanding the invasion and spread of L. lucocephall, there are 32 sites to research the phenology of L. lucocephall with Braun-Blanquet phenology meter; Surveying the growth of L. lucocephalla in different land use at every plot; According 2002 IKONOS satellite image to interpret the distribution of L. lucocephall in Heng-Chung area, and to discuss the relationship between L. lucocephalli distribution and soil composition with soil chemical and physic property; Using different period aero photograph to select three plot, and measuring the area of spread for L. lucocephalla. There are following result of this research and surveying, L. lucocephalla possess a very strong vitality, it could be flowering and seeding two or three times in whole year, it could product about 15,000~20,000 seeds every square meters in a year. The procedure, from budding to grow up, is a significant difference in every different land use type. It’s very difficult to invade into the natural forest without any disturbance; For the sake of failure forestation and reclamation, L. lucocephalla and intolerant spices will invade into mixed woodland, and it will be a new dominant after competition finally; They has a high probability for invasion a..nd spread at abandon rural and graze land. The spread area of L. lucocephalla is 15.7 % in whole investigating area from 2002 IKONOS satellite image; Using 11 soil chemical and physic properties form the distribution of L. lucocephalla, in order to discuss the relationship between the distribution of L. lucocephalla and soil property, the analysis show that the favorite habitation of L. lucocephalla is slight acid and low sand soil texture. Calculating the spread speed of L. lucocephalla from three plots with 1992~1998 aero photograph, the average spread speed is 1,582㎡/year.
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