Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Life Sciences
Soil Chemistry And Nutrition Of North American Red Spruce-Fir Stands: Evidence For Recent Change, J. D. Joslin, J. M. Kelly, H. Van Miegroet
Soil Chemistry And Nutrition Of North American Red Spruce-Fir Stands: Evidence For Recent Change, J. D. Joslin, J. M. Kelly, H. Van Miegroet
Watershed Sciences Faculty Publications
One set of hypotheses offered to explain the decline of red spruce (Picea rubens Sarg.) in eastern North America focuses on the effect of acidic deposition on soil chemistry changes that may affect nutrient availability and root function. Long-term soils data suggest that soil acidification has occurred in some spruce stands over the past 50 yr, with plant uptake and cation leaching both contributing to the loss of cations. Studies of tree ring chemistry also have indicated changes in Ca/Al and Mg/Al ratios in red spruce wood, suggesting increases in the ionic strength of soil solution. Irrigation studies using strong …
Soil Nitrogen Dynamics Following Harvesting And Conversion Of Red Alder And Douglas-Fir Stands, H. Van Miegroet, P. S. Homann, D. W. Cole
Soil Nitrogen Dynamics Following Harvesting And Conversion Of Red Alder And Douglas-Fir Stands, H. Van Miegroet, P. S. Homann, D. W. Cole
Watershed Sciences Faculty Publications
Drastic reductions in NO3- leaching have been observed after harvesting of mature red alder (Alnus rubra Bong.) stands. Our objective was to examine whether these reduction were linked to changes in soil N dynamics. Adjacent alder and Douglas fir [Pseudotsuga menziessii (Mirbel.) Franco] stands on young glacial soils (Alderwood; a loamy-skeletal, mixed, mesic, ortstein Aquic Haplorthod) in western Washington were harvested and replanted with either alder or Douglas fir seedlings; reference plots were established in nearby undisturbed stands. Three years after site conversion, when NO3- leaching declined most drastically in the harvested alder plots, net N mineralization and net nitrification …