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研究了水杉人工林的树冠结构和林分生物生产力．结果表明，不同密度及林龄的林分树冠结构存在较大差异．随着树冠部位上升和林分密度增大，分枝角度逐渐减小；径阶大小与枝叶率成反比，与树冠重量成正比，径阶增大，树冠最大叶量层的位置上移，有效光合面积相对减少．树冠结构的变化直接影响到林分的生物量生产、分配比例和经济生物量．林分干、枝、叶的干物质累积趋势可用Ｒｉｃｈａｒｄ方程描述；林龄增大，分配到主干的生物量比例逐渐增加，分配到枝叶的比例逐渐减少；１５年生时，作建筑材的经济生物量是６２５＞２５００＞１２５０株·ｈａ（－１）的林分，作造纸材的经济生物量为２５００＞６２５＞１２５０株·ｈａ（－１）的林分．
The crown structure and stand biomass productivity of Metasequoia glyptostroboides plantation were studied. The results showed that there were great differences in the canopy structure of the stands with different densities and ages. With the increase of canopy position and stand density, the branching angle decreased gradually. The diameter of log scale was inversely proportional to the branch and leaf rate, directly proportional to the crown weight, and the order of diameter increased. Photosynthetic area is relatively reduced. The change of canopy structure directly affects biomass production, distribution proportion and economic biomass of stand. The dry matter accumulation trend of stems, branches and leaves can be described by the Richard equation. The proportion of biomass allocated to the trunk increases with increasing age, and the proportion distributed to the branches and leaves gradually decreases. At the age of 15 years, The stands were 625> 2500> 1250 plants · ha (-1), and the economic biomass of papermaking was 2500> 625> 1250 plants · ha (-1).