Experiments on functional amounts of individual tree and their dipendency on its size

建立了一种相当复杂的测量白木（Chamaecyparis obtusa， 1986年生11岁）光合作用的仪器。1986年10月，单株暗呼吸的日变化与气温呈指数函数关系，气温系数为2.55；日总光合作用P_g近似为1/P_g = A/I + B，其中I为树顶日总照度，A和B为常数。这个方程使我们能够以中等精度从I预测P_g。(2)杉树凋落物的大小依赖性5种杉树（Cryptomeria japonica， 1985年15年生）的年凋落物1与其粒径x（胸径或净长直径）的关系为1 = a x ^b，其中a和b为常数。1与五棵树的顶干重w_T by 1 = A w_T^B近似实现了类似的关系，其中A和B为常数。四年来中型树木凋落物纪录(编号：16)在五棵树中表明，1 = A‘ w_T ^<B‘>，其中A’和B’为常数，这种关系与之前在五棵树中得到的关系明显不同。(3)树的生长曲线（tree size）强调，树的Bertalanffy生长模型的基础应该建立在实验证据的基础上，即随着时间的推移，树的个体功能与其大小呈异速相关，我们仍然缺乏(2)凋落物研究中所获得的证据。

Photosynthetic production of a hinoki in standing conditionA rather sophiscated appratus for measuing photosynthetic production of a hinoki (Chamaecyparis obtusa, 11-year-old as of 1986) was constructed. In October 1986, daily changes in dark respiration per tree were sgown by an exponential function of air temperaure whose thermal coefficient was 2.55; daily gross photosynthesis P_g was approximated by 1/P_g = A/I + B, where I is daily summed illuminance at the top of tree, and A and B are constant. The equation enables us to predict P_g from I with moderate accuracy.(2) Size dependency of litterfall in sugiAnnual litterfall 1 in five sugi (Cryptomeria japonica, 15-year-oldas of 1985)was nearly related to their size x (dbh o diamter at the clear length) as 1 = a x ^b, where a and b are constant. A similar relationship was approximately realized between 1 and top dry weight of the five trees w_T by 1 = A w_T^B, where A and B are constant.Four-year- record on litterfall of a medium-sized tree(No.16) in the five trees showed that 1 = A' w_T ^<B'>, where A' and B' are constant , and that this relationship was clearly different from the former relationship obtained for the five trees.(3) Growth curve of tree sizeIt was emphasized that the basis of the Bertalanffy growth model in tree should be established with experimental evidence that individual tree functions are allometrically related to its size with the progress of time, and that we still lack such evidence as obtained from our litterfall study mentioned in (2).