A Study on Standing Crops in Phragmitis communis Communities and their Environmental Factors

갈대군락의 현존량과 환경요인에 관한 연구

It was studied of relation between biomass of reed communities (Phragmitis communis) and several environmental factors concerned with such as chlor ine, pH, humus content in soil and depth of seawater submerged. Two sites where were the different geographical conditions were set up. One site had two plots: H plot, at theshallows of seawater, was not submerged except at full tide or at heavy rainfall, and M plot, at medium depth of seawater, submerged at every common tide at inside of a bank along the west seashore of Mu-An-peninsula. The other site also two plots: M' plot, at medium depth, submerged about 10 hours at each tide, and L plot, at deep seawater submerged every tims at tide at the outside of a bank along the eastside estuary of Youngsan river. Maximum standing crop of the reed community was shown on 25th of June: biomass at H M, M' and L plot were respectively 4.65, 3.60, 0.98, and 0.67 kg dry weight per $m^2$. Density of individual at H, M, M' and L plot was 67, 78, 244 and 333 plants per $m^2$. Net production of the terrestrial parts of rred community on the outside of the bank were lesser as much as a sixth than that on inside, but the density of the plant on outside of the bank was higher as much 4 or 5 times than that on inside. It was assumed that the growth of reed plant was inhibited by high chlorine, high pH, less humus in soil and submergence of seawater for long period.