巴西橡胶树PR107生物量研究初探

Biomass of Hevea Clone PR107

利用橡胶树生物量估测数学模型,测算了海南儋州地区2～28龄巴西橡胶无性系PR107生物量的年度变化与累积量,结果表明:(1)在橡胶树生命周期内,茎围与生物量的增长量呈线性增加,并在开割前期出现高峰期,在开割后逐渐变缓慢,进入老龄时,生长速度更慢;橡胶树茎围生长受环境的影响较明显,与树龄、季节、月平均气温、月降雨量和月日照时数直线回归达极显著水平,其回归方程为:y=0.062380-0.013408x1+0.008805x2+0.015716x3+0.000231x4+0.000002379x5;(2)橡胶树各器官(叶、枝、干、皮、根)干物质积累量不仅与季节有关,还与树龄有关。随着一年中季节的变化,干物质积累量呈增长趋势;而随着树龄的增长,枝、干、皮干物质积累量呈增长趋势,而根和叶则呈下降趋势;(3)橡胶树生物量受环境因素和人为因素的影响。橡胶树生物量增量与树龄、季节、月平均气温、月降雨量和月日照时数直线回归达极显著水平,其回归方程为:y=-1661.788621-307.824821x1+209.482331x2+327.130313x3+7.737860x4-9.343308x5;(4)橡胶树生物量的分配格局因不同年龄和器官而异。树干生物量最大,其次是小枝,而其它器官生物量则因年龄大小而有所变化。但在橡胶树整个生命周期内,各器官生物量大小顺序为:树叶>树干>干胶>树根>树皮。

Biomasses of 2-28-year-old rubber trees （Hevea brasiliensis） of Clone PR107 in the Danzhou area, Hainan were determined to observe their annual increment and accumulation by using the mathematical assessment model for rubber tree biomass. In the whole life cycle of rubber tree the girth and biomass of the rubber tree increased linearly and reached a peak before tapping, and the growth gradually slowed down after tapping and became much slower when the rubber tree was at the old age. The growth of girth was obviously affected by environmental factors, and linearly correlated with the age, season, average temperature, rainfall, and sunlight hours at the high significance level. The regression equation was： y=0.062 380-0. 013 408x1 ＋0. 008 805x2 ＋0. 015 716x3＋0. 000 231x4＋0. 000 002 379x5. The dry matter accumulated （DMA） in the organs of the rubber tree, i.e. leaf, branch, trunk, bark and root, was not only related to the season, but also to the age of the rubber tree. The DMA was increasing with the change of season in a year; the DMA in the branch, trunk and bark tended to rise with the tree age but to decrease in root and leaf. The environmental and factitious factors had an important impact on growth of biomass of the rubber tree, and the biomass growth was highly significantly related in a linear way to the tree age, season, average temperature, rainfall, and sunlight hours. The regression equation was： y=-1 661. 788621 -307. 824 821x1 ＋209. 482 331x2 ＋327. 130 313x3 ＋7. 737 860x4 -9. 343 308x5. The distribution pattern of biomass of the rubber tree varied with tree age and organ. The trunk had the highest biomass, followed by small branches, and the others varied in biomass with the tree age. However, in the whole life cycle, the rubber tree produced different biomasses which were in the order of leaf〉trunk〉dry latex〉root〉bark.