Comparative study on ecological chracteristics of seedlings between Fagus crenata and Fagus japonica.

水青冈与水青冈幼苗生态特性的比较研究。

• 批准号: 07640832
• 负责人: YAMAMURA Yasuo
• 金额: $ 1.28万
• 依托单位: Ibaraki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07640832/
• 关键词: Fagus crenata; Fagus japonica; Growth analysis; Photosynthesis; Seedling regeneration; Comparative ecology; Mast year; 物質生産過程

Ecological characteristics of current-year seedlings were compared between co-occurred Fagus crenata (Fc) and F.japonica (Fj) to understand the process of seedling establishment on the forest floor. Seedling populations were censused and growth of the seedlings under different light conditions, and photosynthetic capacity were surveyed. Mast years of both species were determined by age of saplings and growth patterns of annual rings of mother trees.1.Light condition on the forest floor was favorable in spring when the seedlings had cotyledons and severe in summer. Survival of the seedling of Fc was higher than Fj. Mortality of seedlings was in part due to grazing by insects.2.Differences between species in phenology and morphology were observed ; cotyledons of Fj were larger and their longevity was longer (more than twice) than Fc, leaves of Fj were thinner and more spreading and emerged later than Fc. The longevity of the cotyledons was longer in more shaded condition in both species. … More 3.There were not significant differences in total biomass between species in any light conditions. Fj was allocate more dry matter to aerial parts than Fc in more favorable light condition. Maximum photosynthetic rate of Fc was higher and net assimilation rate was higher than Fj. These showed relative trends in light-use of each species ; Fc uses different levels of light resource efficiently by higher flexibility in photosynthetic capacity while Fj by higher morphological flexibility.4.Photosynthetic characteristics of cotyledons were similar to those of typical sun-leaf in both species and maximum photosynthetic rate was comparable to that of leaves. Photosynthetic production by cotyledons was not negligible in annual net production of Fc and more important in Fj.5.Mast years during resent 25 years were 7 times in Fc and 6 times in Fj, and not synchronous between species. Significant correlation between masting and radial growth of trunk was observed in both species, and mast years in the past was capable to be determined from the annual ring patterns. Less

通过比较同生代油柴（Fagus crenatata, Fc）和日本油柴（F.japonica, Fj）当年幼苗的生态特性，了解其在森林地面上的成苗过程。对不同光照条件下的幼苗种群进行了调查，测定了幼苗的生长情况和光合能力。两种树种的最大年数由树龄和母树年轮的生长模式确定。春苗长子叶时林底光照条件较好，夏苗期光照条件较差。Fc的幼苗成活率高于Fj。幼苗的死亡部分是由于昆虫的啃食。物种间物候和形态存在差异；Fj的子叶比Fc大，寿命比Fc长（2倍以上），叶片比Fc薄，展布性强，出芽时间晚。在遮荫条件下，两种植物子叶的寿命都更长。3.……在任何光照条件下，种间总生物量均无显著差异。在较有利的光照条件下，Fj比Fc分配给地上部分的干物质更多。Fc的最大光合速率和净同化速率均高于Fj。这些数据显示了每个物种在轻利用方面的相对趋势；Fc通过较高的光合能力灵活利用不同程度的光能，而Fj则通过较高的形态灵活利用不同程度的光能。两种植物子叶的光合特性与典型太阳叶相似，最大光合速率与叶片相当。子叶光合作用在Fc年净产量中不可忽略，在Fj.5中更为重要。近25 a的最大年数分别为7次和6次，且物种间不同步。两种树种的树干肥大与树干径向生长之间存在显著的相关关系，并且可以通过年轮模式来确定过去的肥大年。少