Print PageProjected climate change models suggest that lodgepole pine will decline in the NW United States by the end of the 21st century. Variations in climatic conditions, including earlier spring warming, may favor establishment of ponderosa pine within the historic lodgepole pine range. Climate change may also affect soil moisture levels and thereby influence fungal communities. Successful plant species migration will be constrained by the distribution or co-migration of fungal symbionts. Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The aims of this study are to examine ectomycorrhizal (ECM) communities on ponderosa pine and lodgepole pine roots and to determine whether ECM communities of ponderosa pine respond to soil moisture and soil chemistry. ECM root tips were collected from 85 ponderosa pine soil cores from 17 sites and from 24 lodgepole pine soil cores for comparison. DNA was extracted from all root tips and Sanger sequencing determined fungal species affinities. Soil chemistry analysis included pH, Bray-phosphorus (P ppm), NO3 (ppm), NH4 (ppm), incubation nitrogen (N ppm), mineralizable N (ppm), total N (ppm), total P (ppm), total carbon (%), and moisture (%H2O).
Results/Conclusions
Preliminary results suggest that species of Rhizopogon, Cenococcum, Cortinarius, Inocybe, Piloderma, and Suillus are dominant in both ponderosa pine and lodgepole pine soil cores. Rhizopogon spp. was ubiquitous in ponderosa pine sites. Nonmetric multidimensional scaling analysis suggested that pH, Bray-P, incubation N, mineralizable N, and NH4 are driving ECM community composition in ponderosa pine. Variation in soil moisture had no effect on ponderosa pine ECM communities on the sites we studied.
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