| The alpine treeline ecotone is characterized as a zone of flagged and krummholz tree growth advancing into areas of alpine tundra. As a zone of ecosystem transition, the alpine treeline ecotone is sensitive to changes in environmental variables, including climate change. While serving as the medium for plant growth, soils develop over time reflecting the interaction of the available climate, organisms, relief, and parent material. If there has been sufficient climate change to promote treeline advance into the alpine tundra, soil characteristics should reflect these changes in the alpine environment.; This research investigated the soils underlying advancing tree fingers and the adjacent alpine tundra to document climate change through changes in soil development. Lee Ridge and White Calf Mountain, located east of the Continental Divide in Glacier National Park, Montana were selected as representative alpine treeline ecotone sites. Soils pits were located in tree fingers and the adjacent tundra at seven different landscape positions: windward, leeward, and centrally within the tree fingers, and within the tundra in positions windward, leeward, upslope, and downslope of the invading tree fingers. Detailed field descriptions were recorded for each soil pit to a 50 cm depth. Ground cover was described at each of the soil pit locations and the vegetation was mapped to describe each of the tree fingers.; Soil characteristics were used to identify changes in soil development due to climate change throughout the time period associated with tree finger establishment. Depth of the A horizons, pH of the A horizons, thickness of the O horizons, depth to visible carbonates, and a soil profile development index were compared using a nested contrast matrix in a general linear statistical model. These five soil characteristics were compared to identify any climate-induced soil differences at three separate levels: between the two study sites, between the soils developed under the tree fingers and under the tundra, and between soils developed in the leeward, windward, upslope, and downslope pit locations in the tree finger and tundra areas.; There were no significant differences (0.05 level) in the depth of the A horizons or the pH of the A horizons at any of the three levels tested. There also was no difference in the profile development index between sites, between tree finger and tundra soils, or between soil pit locations. (Abstract shortened by UMI.)... |
