尖峰岭绿楠树生长过程的研究

GROWTH PROCESS OF MANGLIETIA HAINANENSIS IN JIANGFENGLING, HAINAN ISLAND

对海南尖峰岭地区３０年生的热带乡土树种———绿楠人工林进行了样地调查，并进行了样木横剖树干解析，研究其生长规律及与环境的关系。研究结果表明：（１）绿楠是比较速生的树种，地径、胸径、树高和材积的年生长都呈多峰态曲线；（２）胸径年生长高峰值出现在第１１年，而树高年生长量高峰期晚于地径和胸径生长高峰值出现的年份；（３）在生长初期（８ａ前），材积生长极缓慢，年生长量＜００００９ｍ３，其后开始较快增长，到第１７年出现最大值０００８６８ｍ３；（４）从平均生长量看，地径变化比较平缓；胸径在１４ａ前呈稳态上升趋势，１４ａ后呈平稳发展状态并略有下降；树高在１９ａ前基本呈稳态上升趋势，１９ａ后保持在０５０ｍ／ａ左右，并呈缓慢地下降趋势；材积一直是随着年龄的增加而增加；（５）不同坡位的水肥等条件不同，因而影响了绿楠树的生长，离水沟最近的下坡地的树高和胸径比上坡分别大３７５％和２９１％；（６）绿楠树地径、胸径和树高的连年生长变化趋势基本上与降雨蒸发比（Ｒ／Ｅ）变化趋势相一致，说明水分状况是影响绿楠生长的一个重要环境因子。

The sample plot investigation and stem analysis were conducted in order to study growth rhythm of 30 year old Manglietia hainanensis and to analyze the relationship between the growth and site environments. The results indicated that:(1) Manglietia hainanensis , an indigenous timber tree species, grew quickly, and its annual increment of tree height, stem basal and breast height diameter, and tree volume had many peaks. (2) The time with high peak of annual growth increment of breast height diameter was the 11th year after planting, it was ahead of the time of tree height growth peak. (3)In the early 8years of growth, the tree volume growth was extremely slow with annual growth increment less than 0.0009m 3, then the annual increment became quickly, and the first high peak value (0.00868m 3) appeared in the 17th year. (4) In the view of mean annual increment, the change of stem basal diameter icrement was quite, the increment of breast height diameter was going up steadily from 0.1 to 0.59cm/a in the early 14 years and then descended extremently slowly, the tree height increment presented ascendant tendency in the early 19 years and then declined slightly, the tree volume increment continuously increased along with age increase.(5) The difference in soil moisture, soil fertility and other environment conditions of different slope position caused the distinct growth of Manglietia hainanensis , the tree height and breast height diameter in down slope site were larger 37.5% and 29.1% respectively than these in upper slope site. (6) The change tendency of annual growth increment of tree height, stem basal and breast height diameter was in accord with that of the rain/evaporation rate (R/E) in this area.