When a road is built through a peatland with horizontal water flow, the road can act as a dam; as a result, trees on the “upstream” side of a road can become waterlogged and either die or become stunted, whereas on the “downstream” side of a road, a prolonged drop in the water table can cause the trees to root deeper and grow taller than what is average in the wetland. Interestingly, this phenomenon does not occur consistently. In fact, the same road constructed through two different wetlands may disrupt tree growth patterns in one wetland whereas the other location may appear unaffected. This study examines the conditions that maintain wetlands: landscape position and soil substrate in wetlands with road disturbances and compares the magnitude of stand structure and vegetation changes among different peatland types. We used LiDAR derived tree canopy height and cover from 96 peatlands and vegetation field sample plots from 48 peatlands in North Eastern Alberta. We analyzed the data using Generalized Linear Mixed models to explain the variation in canopy height and cover. Results from this study are anticipated to help guide management decisions for building roads through areas with complex forested wetlands by identifying peatland and substrate types that are more susceptible to road impacts.
