海岸砂地においてニセアカシア林の分布拡大がもたらす成帯構造と種多様性への影響

概要

論文の詳細を見る
Zonation and species diversity in dune vegetation were investigated focusing on the impact of an exotic tree species, Robinia pseudo-acacia, in Atakabayashi National Forest, Central Japan. The vegetation was classified into 11 types. R. pseudo-acacia forests were divided into two types according to the dominance of herbaceous species and shrubs in the undergrowth. R. pseudo-acacia forests appeared on all transects, and covered 36.1% of the transects. Natural zonation was summarized as four zones : strand zone (0-29 m from the shoreline), grassland (30-50 m), small scrub (51-158 m) and forest (over 159 m). The R. pseudo-acacia community was established mainly in small scrub zone, although it is a tall woody species and had a wide ecological niche ranging from the strand zone (14.5 m) to the forest zone (301 m). Hence, this community caused disharmony in the coastal zonation. In contrast to the increase in species diversity of the native communities with distance from the shoreline, R. pseudo-acacia community decreased the species diversity. It was suggested that nitrophilous plants such as Briza maxima and heliophilous plants such as Cocculus orbiculatus had a co-dominance effect with R. pseudo-acacia to decrease the species diversity.
日本生態学会の論文
1997-08-25