SEASONAL-VARIATION OF FUNGAL BIOMASS IN THE SEDIMENT OF A SALT-MARSH IN NEW-BRUNSWICK

In a marsh in New Brunswick, Canada, belowground biomass of Spartina a lterniflora consistently exceeded aboveground biomass by a factor of a pproximately 9. Both values peaked in July. Redox potential of the sed iment was negative at all levels tested (2, 6, and 11 cm below surface ), and was negatively correlated with depth. Concentrations of ergoste rol, a sterol typical of higher fungi, were negatively correlated with redox potential and were highest in roots and rhizomes in July and Au gust, 1-3 cm below the surface. These maxima corresponded to a fungal content of approximately 0.6% per ash-free dry mass of Spartina materi al. Balsa wood panels buried in anaerobic salt marsh sediment were col onized by fungi within 12 weeks. Eight fungal species isolated from S. alterniflora roots did not grow in the absence of oxygen, but were ab le to grow downward into an anaerobic medium.