Studies in maintenance and regeneration mechanisms of a coppice forest in cool-warm temperate transitional zone

日本中部茨木县北方寒暖温带过渡带矮林次生林以栎（Quercus serrara）、栗（Castanea crenata）、鹅耳枥（Carpinus）、槭（Acer）等为主，从幼树和冠层树的枝结构和枝动态研究了栎（Quercus serrara）、疏花鹅耳枥（Carpinus laxiflora）和栗（C.Crenata）的建立机制，1.测定了以锯齿栎和钝齿栎为主的矮林（约20年生，树高10-12 m）的现存量。这两个物种占总断面积的66%。2<-1>.锯齿栎和钝齿栎的最大光合速率约为10 μ mol·s ~（-1<-2>）<-1>，疏花栎的最大光合速率约为8 μ mol·<-2>s <-1>~（-1）。随后进行林窗形成、修剪矮竹、修剪灌木和对照处理。相对生长率和存活率高，在唯一的差距。4.锯齿栎和钝齿栎在幼树和冠层树中都有第一、二次枝的形成。疏花锦鸡儿幼树和冠层树的枝梢伸长存在差异。疏花青冈的叶片寿命、单叶面积、比叶重和单位茎长的茎重均显著小于锯齿青冈和钝齿青冈。单位叶面积的茎长是锯齿栎和钝齿栎的3 ~ 5倍。疏花锦鸡儿的高伸枝效率有利于成苗和冠层树的形成。

A coppice secondary forest of cool-warm temperate transitional zone in northern part of Ibaraki Prefecture, central Japan is dominated by Quercus serrara, Castanea crenata, Carpinus, Acer and so on. The establishment mechanism of Q.serrata, Carpinus laxiflora and C.Crenata ware examined from the shoot structure and shoot dynamics of both saplings and canopy trees, and physioecological characteristics.1.The standing crop of the coppice forest dominating by Q.serrata and C.crenata (ca.20-years-old, 10-12 m in height) was measured. These two species occupied 66% of the total basal area. The standing crop was 590.5 kga^<-1>.2.Maximum photosynthesis of Q.serrata and C.crenata was ca.10 mumolm^<-2>s^<-1> and that of C.laxiflora was 8 mumolm^<-2>s^<-1>.3.The influence of upper layr plants on the seedling establishment of Q.serrata and C.laxiflora was examined. Following treatments such as gap formation, mowing dwarf-bamboo, mowing shrub and control were made. Relative growth rate and survivorship were high at the only gap. The regeneration of the two species would occur in the only gap.4.In Q.serrata and C.crenata first and second shoots were formed in both saplings and canopy trees. The shoot extension of C.laxiflora differed in saplings and canopy trees. In saplings only first shoot extended during growing season and in canopy trees first and second shoots were formed.5.The life span of leaves, area of individual leaves, specific leaf weight and stem weight per unit stem length of C.laxiflora were smaller significantly than those of Q.serrata and C.crenata. The stem length per unit leaf area of C.laxiflora was three to five times as long as Q.serrata and C.crenata. A high efficiency of shoot extension of C.laxiflora contributed to the establishment of seedlings and development to canopy trees.