Portal de Periódicos da CAPES

Fruiting of Hypogeous Fungi in Oregon Douglas-Fir Forests: Seasonal and Habitat Variation

1991; Taylor & Francis; Volume: 83; Issue: 3 Linguagem: Inglês

10.1080/00275514.1991.12026018

1557-2536

Daniel L. Luoma, Robert E. Frenkel, James M. Trappe,

Lichen and fungal ecology

Hypogeous sporocarps of ectomycorrhizal fungi were harvested from 10 Douglas-fir stands representing a variety of natural habitats. Calculated over all stands, total dry standing biomass equaled 1.3 kg/ha, and the maximum single stand sample biomass equaled 9.9 kg/ha. Forty-seven species of hypogeous fungi were recorded; 14 accounted for 94% of the total biomass. Elaphomyces granulatus, Gautieria monticola, Hysterangium coriaceum, Leucogaster rubescens, and Rhizopogon parksii accounted for 73% of the biomass.In contrast to epigeous species in the study area, hypogeous sporocarp production was higher in spring than in fall. Production was evaluated in five Douglas-fir habitats (wet old-growth, mesic old-growth, dry old-growth, mesic mature, and mesic young), forming two gradients, wet to dry and young to old. The mesic mature forest habitat had the highest standing biomass value (2.2 kg/ha) of all the habitats studied. The dry old-growth forest habitat had the lowest (0.7 kg/ha).Individual species showed strong seasonal trends. Most had spring or summer production peaks. Some also showed differences in sporocarp production by habitat. For example, Leucogaster rubescens had peak biomass in the dry old-growth habitat, and the peak biomass of Leucophleps magnata was in habitats other than old-growth. In contrast, Rhizopogon vinicolor was well distributed throughout all habitats.Analysis of sample value distributions indicated that samples of small total area (≤800 m2) tended to overestimate sporocarp biomass, because biomass was strongly skewed toward high values. Additionally, systematic placement of the largest practical number of quadrats reduced the tendency of localized sporocarp concentrations to cause further overestimation of standing biomass, when extended to a grams per hectare basis.