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的常绿植物的生态生理学和物质经济，以阐明在营养限制条件下常绿植物在较常见的条件下占优势的机理。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）常绿氮的氮的年失误率较低，（2）常绿叶子用作储存器官和氮从叶子中恢复为春季的叶子到增长的芽，（3）最大的光合速率较低，但每天都没有差异，因为每天都没有差异，因为较高的摄影效率不再造成图片的生产。由于生长季节之前和之后的光合作用，落叶树。因此，常绿植物的氮利用效率（NUE）更高。（3）熔岩床上的常绿树在叶子中具有大量的储存氮，在叶子中，它被转移到在更有利的光线状态下生长的芽，并且比在深层土壤上具有更高的nue。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，并且在凉爽且营养限制的地点中造成了高度nue。