Growth and production of Sphagnum mosses from Takadayachi Moor in Hakkoda Mountains,northeast Japan-1-Dry matter production estimated from photosynthesis and respiration

Photosynthesis of Sphagnum tenellum, S. papillosum and S. nemoreum were measured monthly under the optimum water contents in their growing season of 1989. These species were dominant in Takadayachi moor of Hakkoda Mts. in northern part of Honshu. S. tenellum is growing in the hollows and others are in the hummocks. The surface layer temperature of each moss population and photon flux density (PFD) were measured and recorded with some loggers. The dry matter production in photosynthetic layer of each species was calculated with the relation between photosynthetic rate and moss temperature, PFD and the water content. Then the respiration of nonphotosynthetic layer was subtracted from the dry matter production. The ranges of the dry matter accumulations in growing seasons of 1990, 1991 and 1993 were 141-206 g m-2, 32-190 g m-2 and 187- 219 g m-2 in S. tenellum, S. papillosum and S. nemoreum, respectively.