Crater Lake National Park presents an excellent opportunity for ecological research due to its relatively pristine landscape, the protection of its natural features, its infrastructure, and a Park administration supportive of scientific inquiry and restoration ecology. The research presented here examines the responses of fungi to various forms of perturbation....
Soil respiration, or the combined CO₂ emissions from roots and soil microorganisms, constitutes one of the largest losses of carbon (C) from terrestrial ecosystems. The major drivers of soil respiration, which include soil moisture, temperature, and substrate quality, have been known for some time. Nevertheless,
correlations between these drivers and...
Intimate associations with reactive metal species permanently protect soil organic matter (SOM) from microbial access and oxidation, contributing to the build-up of organic carbon (C) stocks in soils. It is increasingly recognized, however, that such associations can be reversible and that reactive metal species might even facilitate the oxidation of...
Dense hyphal mats formed by ectomycorrhizal (EcM) fungi are prominent features in Douglas-fir (Pseudotsuga menziesii) forest soils and have been estimated to cover up to 40% of the forest floor in some stands. Although previous studies have examined various aspects of EcM fungi, little is known about their associated microbial...
Mycorrhizae are important for plant growth, particularly in nutritionally poor soils. Vesicular-arbuscular mycorrhizae (VAM) are the primary form of mycorrhizae found in tropical plants, and their persistence in the soil as colonizing fungal propagules following deforestation cannot be directly
measured. Utilizing the "most probable number" (MPN) method for estimating infective...
Seedlings of Gaultheria shallon, Pseudotsuga menziesii, Rhododendron macrophyllum and Tsuga heterophylla were grown together in the greenhouse in soils from three young managed Douglas-fir forests in the Oregon Coast Range. The main objectives were 1 )to evaluate the ability of ericaceous plants and overstory conifers to share compatible mycorrhizal fungi...
Ectomycorrhizal fungi (EmF) form symbioses with trees. These symbioses profoundly influence forest ecology. Certain EmF form specialized profusions of hyphae, known as ectomycorrhizal fungal mats (mats) which are visible to the naked eye, alter forest soil biogeochemistry, substantially contribute to soil microbial biomass/respiration and support unique microbial communities. Piloderma and...
Fuel accumulation and climate shifts are predicted to increase the frequency of high-severity fires in ponderosa pine (Pinus ponderosa Dougl. ex Laws) forests of central Oregon. The combustion of fuels containing large downed wood can result in intense soil heating, alteration of soil properties, and mortality of microbes. Previous studies...
Mat-forming ectomycorrhizal (EcM) fungi represent a prevalent constituent of many temperate forest ecosystems and create dramatic changes in soil structure and chemistry. EcM mat soil have been shown to have increased microbial respiration rates and have been hypothesized to harbor unique assemblages of fungi and bacteria. The objectives of this...
Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture,...