Analysis of canopy structure of multi-species plant communities

多物种植物群落冠层结构分析

基本信息

批准号：
06454007
负责人：
HIROSE Tadaki
金额：
$ 4.35万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

项目摘要

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

植物群落由一系列植物高度不同的物种组成，占据冠层上层的高优势物种接收大部分光子通量密度，而占据下层的小型从属物种接收一小部分可用光子。，将相对更多的生物量投入到支持组织中，以将其叶子定位在冠层的高处，因此高的优势物种和小型的从属物种之间单位地上生物量的光子吸收相似。 (1) 在川田的芒草林中，从属物种如珍珠菜的单位地上生物量的光子吸收在生长季节早期较高，而优势种芒草在生长季节后期较高，这使得从属物种的单位地上生物量的光子吸收量较高。与优势芒草共存 (2) 在温室中建立水稻 (C3) 和小米 (C4) 的混合林，并进行竞争…… 更多对这些物种进行了分析。虽然小米比水稻发芽晚，但其生长速度比水稻要大。水稻使小米的生长速度降低了 5%，而小米使水稻的生长速度降低了 30%。一个估计密集林中个体光合作用的模型，并分析了参与大小等级发展的因素，与抑制相比，高大优势植物每单位地上生物量具有更大的光子吸收率和每单位吸收光子通量密度更大的光合速率。 (4) 建立了一个模型来分析光合蛋白质之间不同氮分配对光合能力的影响。根据光照条件，分配可导致光合效率提高 20%。 (5) 我们比较了太阳之间的蛋白质分配。（Chenopodium album）和遮荫植物（Alocasiamacro rhiza）的蛋白质分配接近理论最佳值。