[pp.23-30]
Teruo ARASE (Shinshu University)
Abstract:
In the present study, aboveground biomass of forest floor vegetation in a larch forest at the northern foot of Mt. Fuji was surveyed seasonally over a period of four years. Twelve monitoring plots (6 vegetation divisions・2 replications) consisting of 2.5 m・2.5 m area were established for sequential vegetation surveys within the National Institute of Environmental Studies' CO2 flux research site (200 m - 200 m). Six sampling plots consisting of 4 m・4 m area were established for direct measurement of biomass adjacent to the research site. Classification of vegetation was made at three stages: undivided vegetation (non-division), division of vegetation into three rough groupings (rough division), and a further segmentation into six subdivisions (subdivision). Reliable estimates of vegetation biomass were obtained by applying allometric equations to vegetation data and actual values of biomass in the non-division and rough division stages. Biomass increased from May to June each year, and afterwards it varied slightly across years but exhibited no significant increase or decrease. Interannual fluctuations in biomass did not exhibit statistical significance and total biomass in the spring of each year displayed constancy. A maximum biomass of 2.6 Mg・ha-1 was reached in September, which was equal to the leaf biomass of the larch tree overstory.
Key Word:
forest floor vegetation, biomass, estimation, seasonal change, Japanese larch forest