Analysis of canopy structure of multi-species plant communities

一个植物群落由一系列植物高度不同的物种组成。高占主导地位的物种在树冠上层接收大部分的光子通量密度，而小的从属物种占据下层接收小部分的可用光子。然而，高大的物种投入相对更多的生物量来支持组织，以将其叶片定位在树冠的高处。因此，单位地上生物量的光子吸收在高的优势种和小的从属种之间是相似的。通过2年的研究发现：（1）川比芒林下，排草等下位种单位地上生物量的光子吸收在生长季前期较高，而优势种芒在生长季后期较高。这使得从属物种与优势芒草共存。(2)在温室条件下建立了水稻（C3）和谷子（C4）混交林， ...更多信息 分析了这些物种之间的关系。谷子虽然比水稻发芽晚，但生长速度却比水稻快。水稻使谷子的生长量减少5%，谷子使水稻的生长量减少30%。(3)我们建立了一个模型来估计在一个密集的林分个体的光合作用，并分析了大小等级的发展所涉及的因素。高大优势植物单位地上生物量的光子吸收量和单位吸收光子通量密度的光合速率均大于被抑制植物，加剧了林分的大小层次。（4）建立了不同氮素在光合蛋白质间分配对光合能力影响的模型。根据光照条件的最佳分配，导致光合效率增加20%。(5)我们比较了阳光（藜）和遮荫（海芋）植物之间的蛋白质分配。这两个物种的蛋白质分配接近理论最佳。少

A plant communty consists of a range of species different in plant height. Tall dominant species occupying upper layrs in the canopy receive a large fraction of photon flux density, while small subordinate species occupying lower layrs receive small fractions of available photons. Tall species, however, invest relatively more biomass to supporting tissues to position their leaves high in the canopy. Thus photon absorption per unit aboveground biomass is similar between tall dominant and small subordinate species. Through the two-year study, we found : (1) In the Miscanthus sinensis stand at Kawatabi, photon absorption per unit aboveground biomass of subordinate species such as Lysimachia japonica was high early in the growing season, while that of dominant Miscanthus sinensis was high late in the growing season. This enables subordinate species to coexist with dominant Miscanthus sinensis. (2) Mixed stands of rice (C3) and millet (C4) were established in a greenhouse and competition be … More tween these species was analyzed. Although millet germinating later than rice, its growth rate was larger than rice plants. Rice reduced the growth of millet by 5%, while millet reduced the growth rate of rice up to 30%. (3) We developed a model to estimate photosynthesis of individuals in a dense stand and analyzed factors involved in the development of size hierarchy. Tall dominant plants had larger photon absorption per unit aboveground biomass and larger photosynthetic rates per unit absorbed photon flux density than suppressed plants, intensiflying the size hierarchy of the stand. (4) A model was made to analyze the effect on photosynthetic capacity of different nitrogen partitioning among photosynthetic proteins. The optimal partitioning, depending on light conditions, lead to up to 20% increase in photosynthetic efficiency. (5) We compared protein partitioning between sun (Chenopodium album) and shade (Alocasia macrorrhiza) plants. Both species had protein partitioning close to the theoretical optimum. Less