In this paper,the effect of cutting length,temporal planting time and transplanting time on survival rate, height and basal diameter of Pinus taeda,Pinus elliottii and Pinus massoniana cutting seedlings has been studied The results showed that because of difference of biological properties among three tree species, suitable cutting length,temporal planting time and transplanting time are different The suitable temporal planting time and transplanting time of Pinus taeda is December 30 and April 10,the best cutting length is 4～8 cm; the suitable temporal planting time and transplanting time of Pinus elliottii is January 15 and April 10,the best cutting length is 12 cm; the suitable temporal planting time and transplanting time of Pinus massoniana is December 15～30 and April 10,the best cutting length is 6～8 cm
The changing pattern of tree species diversities in gaps at different developmental stages of evergreen broad -leaved forest in Mountain Wuyi was analyzed in this paper. The results show that the tree species diversity indexes in gaps are larger than that in non-gap stands, but the ecological dominance shows the opposite discipline. The tree species diversity indexes are changed in expanded gaps of different sizes and reach the highest in those with a size smaller than 100 square meter, but reach the lowest in the expanded gaps with a size larger than 300 square meter. Species richness, species diversity indexes and mean degree indexes of the species higher than 1.5m show a general trend with the development of gaps, reaching the highest level in the gap ages of about 10～20 years, but the lowest level in first ten years. The tree species diversity indexes and mean degree indexes in regeneration layer of gaps are decreased in the first 10 years, reaching the lowest level in 10～20 years after gap formation, and then are increased in the next 30 years, reaching the largest level in 40～50 years, but a slow trend of decreasing after 50 years after gap formation. Gap formation provides the power for regeneration of tree different species. In order to preserve the species diversity, it is very important to make gaps in a proper way in forest production.
In this paper,the effect of time and retention height of topping on quantity,length and basal diameter of coppice shoot of Pinus taeda,Pinus elliottii and Pinus massoniana has been studied The results showed that because of difference of biological properties among three tree species, suitable time and retention height of topping among three tree species are different The suitable topping time of Pinus taeda is August 20 to August 25,the best retention height of topping is 15 cm; The suitable topping time of Pinus massoniana is July 30, the best retention height of topping is 8 cm; The suitable topping time of Pinus elliottii is August 15 to August 20,the best retention height of topping is 15 cm
Determination and analysis were made in the fiber morphology of Michelia tsoi wood from plantation and natural forest in this paper.The results showed that fiber length of M.tsoi wood from natural forest belonged to short fiber between the first and fourth year,while it belonged to middle fiber length between the fifth and tenth year.Ratio of fiber length to fiber width of M.tsoi wood from natural forest belonged to small size between the first and third year,while it was higher between the fourth and tenth year(more than 45).Fiber length of M.tsoi wood from plantation belonged to short fiber between the first and fifth year,while it belonged to middle fiber length between the sixth and tenth year.Ratio of fiber length to fiber width of M.tsoi wood from plantation belonged to small size between the first and fifth year,while it was higher between the sixth and tenth year(more than 45).Fiber quality of M.tsoi wood from natural forest was superior to that from plantation according to the fiber length and ratio of length to width.
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