Studies on life patterns of evergreen broad-leaved trees growing in cool and nutrient-limited sites

凉爽和营养有限地区常绿阔叶树生活模式的研究

基本信息

批准号：
12640609
负责人：
YAMAMURA Yasuo
金额：
$ 1.98万
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：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

(1) Ecophysiology and matter economy were investigated for evergreen plants in montane and subalpine sites in Mt Fuji, a volcanic mountain in central Japan, to clarify the mechanism of dominance of evergreen plants under nutrient-limited conditions.(2) On a lava bed in the montane site, forest canopy is dominated by an evergreen conifer (Pinus densiflora) and under-canopy layer is dominated by evergreen broadleaf trees (Irex pedunculosa, Pieris japonica). Evergreen broadleaf trees were different from deciduous ones in several ecophysiological features; (1) Annual turnover rate of nitrogen of evergreens was lower, (2) Evergreen leaves served as storage organs and nitrogen was retranslocated from the leaves to growing shoots in spring, (3) Maximum photosynthetic rate of evergreens was lower, but there were no difference in daily matter production because midday depletion of photosynthetic activity did not occur in evergreens, (4) Annual productivity of evergreens was higher because of photosynthetic activity before and after growing season for deciduous trees. Consequently nitrogen use efficiency (NUE) of evergreens was higher.(3) The evergreen pine tree on the lava bed had much storage nitrogen in leaves, which was retranslocated to shoots growing under more favorable light condition, and had higher NUE than that on a deep soil. High NUE was also observed in an evergreen herb in the subalpine site. Evergreen leaves served to photosynthesize under a favorable light condition in early spring.(4) These results indicated that evergreenness caused a conservative nutrient economy and high NUE in cool and nutrient-limited sites.

（1）研究了日本中部火山山的富吉（Mt Fuji）的常绿植物的生态生理学和物质经济，以阐明在营养限制的条件下常绿植物的优势机制。（2）在熔岩床上。（2）在山地地点，森林冠层由常绿针叶树（Pinus densiflora）主导，并且囊层层由常绿阔叶树（Irex Pedunculosa，Pieris Japonica）主导。在几种生态生理特征中，常绿阔叶树不同于落叶树。（1）常绿的氮的年营业率较低，（2）常绿叶作为储存器官和氮在春季从叶子中重新分配到生长的芽，（3）（3）最大的常绿光合速率较低，但没有较低的光合作用率每日物质生产的差异是因为在常绿植物中没有发生光合作用活动的中午耗尽，（4）（4）由于落叶树的生长季节之前和之后，常绿植物的年生产力更高。因此，常绿的氮利用效率（NUE）较高。（3）熔岩床上的常绿松树在叶子中具有很大的储存氮，在叶子中，它被重新分配为在更有利的光线状态下生长的芽，并且比在较高的nue中，比在一个上更高的nue。深层土壤。在亚高山位点的常绿草药中也观察到了高nue。常绿叶子在早春在有利的光线状态下进行光合作用。（4）这些结果表明，常绿性导致了保守的营养经济性，并且在凉爽和养分限制的地点中造成了高度的nue。