森林立地学会誌 森林立地41(1），1999，7～11
Jpn.J.For.Environment41（1），7－11
1999
Nutrient Distribution and
Content in Plant Tissue, Forest Floor, and Litterfall in Four Pioneer Stands on
Volcano Mt. Showa-Shinzan
Hyun-Shik MOON
Masahiro HARUKI
This study was conducted to clarify the
distribution and content of nutrients in plant tissue (foliage, branch, root),
forest floor (Ao layer), and litterfall in four pioneer stands, i.e., aspen (Populus sieboldii M.), alder (Alnus maximowiczii C.), poplar (Populus maximowiczii H.), and black
locust (Robinia pseudo-acacia L.)
stands established on Mt. Showa-Shinzan. The content of N in foliage was higher
in black locust and alder than them in aspen and poplar. Among the various
tissues,. nutrient concentrations were higher in foliage than in branch or
root. The concentration of N on the forest floor was the highest in the alder
stand. The contens of nutrient on the forest floor was in the order of Ca＞N＞Na＞Mg＞K＞P. The dry matter of the understory
biomass was most abundant in black locust stand, but dry weight of organic
material on the forest floor did not show significant difference among the
study stands. The production of litter were higher in the alder and black
locust stands than in the poplar and aspen stands, and the content of N in
litter was high in both alder and black locust which are N-fixing species.
These results suggested that these early pioneer species would be well adapted
to nutrient-poor sites after volcanic eruptions because the rapid growth and N
fixation properties that increased nutrient availability in the forest
ecosystem.
文炫植、春木雅寛：昭和新山の4つの先駆林分の植物器官，林床，落葉落枝における養分分布と含有量。
この研究は昭和新山に成立した4つの先駆林分（ヤマナラシ，ミヤマハンノキ，ドロノキ，ニセアカシア林分）での各優占種の器官（葉，枝，根），林床（Ao層），落葉落枝（litterfall）における養分分布と含有量を明らかにするために行われた。葉における窒素量はヤマナラシとドロノキよりもニセアカシアとミヤマハンノキの方が高かった。養分は枝と根よりも葉に多く分布していることが明らかになった。各種調査林分の林床における窒素量は，他の林分と比ベミヤマハンノキ林分が高い値を示した。林床における養分含有量はCa＞N＞Na＞Mg＞K＞Pの順であった。下層植生の乾物量はニセアカシア林分で最も高かったが，林床における有機物の乾重は調査林分間に大きな差は見られなかった。1年間のリターフォールはミヤマハンノキ林分とニセアカシア林分がドロノキ林分とヤマナラシ林分より高い価を示しており，窒素含有率も窒素固定植物であるミヤマハンノキとニセアカシアが高かった。