小河川におけるミクリ(Sparganium erectum)群落による有機土壌、栄養塩堆積の機構および生長促進への影響

抄録

MIkuri, Sparganium erectum, is an endangered species locally. Characteristics of annual growth pattern was observed in a small stream separately between above- and belowground biomass, and new and old shoots. Succeeding upward and downward material translocation was recognized from between above- and below ground biomass from spring to summer, and at the time of new shoot formation from summer to winter. Sparganium hibernates in submerged form, is transformed into emergent form in spring, then grows rapidly.

Many shoots collapse in June and December, then stuck the current in the community, declining the flow velocity. An amount of organic and inorganic sediments is accumulated in a short time on the bottom, producing nitrogen and phosphorus rich substrate there. Then, 53.9% of nitrogen is taken up by the plant, when growing. Presumably it is one of strategies to develop a community there.