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Geology topics

John M. Kabrick

Publications and source records attributed to John M. Kabrick.

2 recordsLinked to original sources

Effects of ungulate browsing on forest assisted migration strategies to conserve ecosystem function

Forest managers recognize that proactive management strategies, such as forest assisted migration (FAM) of tree species, intended to accelerate the pace of forest adaptation, may be necessary to maintain resilient forests and combat the stressors of climate change. However, the impact of interactions between climate change and ungulate browsers of trees, both of which have profound effects on the landscape, on the success of FAM efforts is unknown. We used a forest landscape model (LANDIS-II) to simulate assisted migration and browsing by ungulate (white-tailed deer [ Odocoileus virginianus ]) populations on a northern Wisconsin (USA) landscape under alternate climate futures. After accounting for effects of FAM strategy and climate change scenario, simulated ungulate browsing reduced species richness and the proportion of the landscape with tree species preferred by browsers and resulted in more of the landscape developing into novel forest communities that supported fewer ecosystem goods and services. Our results suggest that managers may need to select FAM species less preferred by ungulates or use seedling protection measures to mitigate the negative effects of chronically high ungulate populations in efforts to transition future forests to sustain ecosystem goods and services.

Wisconsin

Changes to oak woodland stand structure and ground flora composition caused by thinning and burning

Our objective was to quantify the cumulative effects of prescribed burning and thinning on forest stocking and species composition at a woodland restoration experiment site in the Ozark Highlands of Missouri. Our study used four treatments (burn, harvest, harvest and burn, control) on three slope position and aspect combinations (south, north, ridge) replicated in three complete blocks. Harvested stands were thinned from below to 40 percent residual stocking. Two prescribed fires were applied to both burn and harvest-burn treatment units in a 5-year period. Results reflect changes that have taken place over a 6-year period, from pretreatment conditions to 1 year after the last fire. In this period, there was a 10-percent reduction in the stocking in burned stands compared to control and a 6-percent reduction in harvested and burned stands compared to harvested stands. Compared to the control, percentage ground cover of woodland indicators was seven times greater in burned stands, six times greater in harvested stands, and 22 percent greater in harvested and burned stands. Th ere was no significant (P > 0.05) interaction between aspect and treatment on stocking or ground flora cover. Th is study indicated that silvicultural treatments do achieve various goals that are common to managers who aim to restore woodland communities.

Missouri