福建柏人工林生态系统生产力的研究

A STUDY ON ECOSYSTEM PRODUCTIVITY OF FOKIENIA HODGINSII PLANTATION

以双重抽样法和“相对变比生长”模型（ｙ＝ａｘｂｅｃｘ）、“树形管道”模型（ｙ＝ａｘｂＬｃ）测定４个福建柏人工林的生物量。结果表明：２４年生福建柏人工林密林分（Ⅱ类立地，２７００株／ｈｍ２）和２６年生稀林分（Ⅰ类立地，１２１６株／ｈｍ２）的生物量，前者为１７８．２４０ｔ／ｈｍ２（乔木层占９９．６％），后者为１５５．２０４ｔ／ｈｍ２（乔木层占９９．６％）；前者年平均净生产量为７．６２８ｔ／（ｈｍ２·ａ），后者为６．０７５ｔ／（ｈｍ２·ａ）；乔木层干物质的密度，前者为１３．９ｔ／（ｈｍ２·ｍ），后者为１１．５ｔ／（ｈｍ２·ｍ）。树体各器官生物量分配的大小顺序为：树干＞根＞枝＞树皮＞叶。乔木层各器官生物量的威布尔分布均是正偏的。由于分布均是从小径阶开始，所以正偏即是朝偏向小径阶分布。密林分起始径阶小，稀林分的起始径阶大且前者正偏程度比后者来得大．表明数量与质量是二律背反逻辑。林木生物量的年间生产量和年平均生产量于２４～２６年生时相交，其年间生产量最大值出现于１５～１８年生。

With the variable allometric rates model and the tree form pipe model for F. hodginsii plantation of 23 to 26 years of growth, the biomass of four plantations in Fujian Province was measured. The total stands biomass was 178. 240 t/ hm2 at maximum (No. 25 plot, site class Ⅱ, 2700 stem/hm2, 24 years old) and 155. 204 t/hm2 at minimum (No. 22, site class Ⅰ, 1216 stem/hm2, 26-years old). The productivity of the fomer was 7. 628 t/ (hm2·a) and the latter was 6. 075 t/(hm2. a). Components biomass was 108. 145. 16. 532. 17. 455. 7. 735 and 27. 732 t/hm2 for stem. barks、branches、leaves and roots, respectively for the former, while 88. 528、 12. 06、21. 618、8. 016and 24. 413 t/hm2 were for the latter, respectively. Weibull distribution of stands components biomass was positively skewed, at C<3. 6 (Since the distribution begins from a small diameter, biomass inclines toward the smaller diameter), but the greater the density stock, the smaller the diameter of distribution the more the density, the greater the diamerer of distribution stock. The logistic increment eguation of biomass cumulative process showed that their stage of maximum growth was at 15 to 18-years of age.