| 概要 |
北海道産落葉広葉樹11種（ウダイカンバ，アサダ，ミズナラ，ハルニレ，オヒョウ，カツラ，ホオノキ，シナノキ，ハリギリ，ヤチダモ，アオダモ）の伸長・肥大成長と着葉枚数の季節変化，および5種（ウダイカンバ，ミズナラ，ハルニレ，カツラ，ヤチダモ）の物質分配の季節変化について，当年生あるいは1年生実生を笛畑で生育させ，6月下旬から11月中旬にかけて調査した．伸長成長および着葉枚数の季節変化においては2群に分...類することができた．8月下旬あるいは9月中旬に着葉枚数が最大になり（順次開葉型），伸長成長量の大きなウダイカンバ，アサダ，ハルニレ，オヒョウ，カツラの種群，および着葉枚数に変化が少なく （一斉開葉型），伸長成長量の小さなミズナラ，ホオノキ，シナノキ，ハリギリ，ヤチダモ，アオダモの種群である．また，個体成長率（RGR）から伸長および肥大成長の季節変化を解析した結果，伸長成長が優勢なパターン，肥大成長が優勢なパターン，明確な優劣が認められない中間的なパターン，肥大成長優勢→伸長成長優勢→肥大成長優勢というように優劣関係が変化するパターンの4パターンに分けられた．先駆樹種であるウダイカンバは伸長成長が優勢なパターンを示し，極相林優占樹種であるミズナラ，ヤチダモは肥大成長が優勢なパターンを示した．物質分配の季節変化においては，ウダイカンバは枝への分配率が高く，8月下旬まで葉の分配比率が高まった．ミズナラは枝への分配率が低く，根への分配率が上昇した．ヤチダモは全く枝を生産しなかった．ハルニレ，カツラは生育期間中における分配率の変化が比較的小さかった．T／RおよびC／Fの季節変化においては，ミズナラが他の4樹種とほ異なった変化を示し，特にC／Fは直線的に上昇した．伸長・肥大成長，着葉枚数，および物質分配における季節変化は樹種によって異なっており，それらの特徴は，遷移系列上の位置と関係あるものと考えられた．
To clear the growth characteristics of deciduous broad-leaved tree seedlings distributed in Hokkaido, nothern Japan, the seasonal changes of diameter growth, height growth and number of live leaves were investigated on 11 species,Betula maximowicziana, Ostrya japonica, Quercus crispula, Ulmus davidiana, U. laciniata, Cercidiphyllum japonicum, Magnolia obovata, Tilia japonica, Kalopanax pictus, Fraxinus mandshurica and F. lanuginosa, and the seasonal patterns of dry matter partitionings were surveyed on 5 species, B. maximowicziana, Q. crispula, U. davidiana, C. japonicum and F. mandshurica, for one growing season. Seedlings used in this study were current or one year, and wildlings except Q. crispula seedlings. These 11 species were divided into two groups based on the seasonal changes of height growth and number of live leaves. 5 species, B. maximowicziana, O. japonica, U. davidiana, U. laciniata and C. japonicum made one group that the height growth was larger, and the maximum of the number of live leaves was more distinct. Other 6 species, Q. crispula, M. obovata, T. japonica, K. pictus, F. mandshurica and F. lanuginosa formed another group that the height growth was smaller, and the changes of the number of live leaves was obscure. Besides, on the seasonal changes of relative basal diameter growth rate (RDGR) and relative height growth rate (RHGR), these changes were epitomized into four patterns (Fig. 9). Pattern A was RHGR superior, pattern B was RDGR dominant, and pattern C and D were intermediate type between pattern A and B. Pioneer species, B. maximowicziana indicate pattern A growth changes. On the other hand, late successional and dominant species of climax forests in this area. Q. crispula, F. mandshurica were showed pattern B growth changes. On the seasonal changes in dry matter partitionings, B. maximowicziana and Q. crispula showed the contrastive characteristics each other. The branch rates of B. maximowicziana were heighest, the leaf rates were increase and the root rates were decrease until the latter part of August. The barnch rates of Q. crispula were lower and the root rates went up about 80% at mid-November. Moreover, T／R values were smaller and C／F values rose straight. Seasonal patterns of the growth, the number of live leaves and the dry matter partitioning were different between species, and these characteristics were related to the position on the sere in eastern Hokkaido.続きを見る
|
Mendeley出力
