Habitat filter, priority efect and ecological engineering (feedbacks) of dominant species in post-fire succession

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Logging and fire in the nutrient poor black spruce-Kalmia forest of eastern Canada often leads to extensive ericaceous heath formation, which interferes with conifer regeneration. Not enough is known about the duration and dynamics of the ericaceous heath. Some suggest it lasts for several years to several decades others suggest alternate stable states based on tree ring and paleocological evidence. This understanding is critical in sustainable forest management and conservation. Failure or delay in conifer regeneration translates into loss of forest productivity and transformation of multi-layered forest to simplified low growing heathland. Limited areas of Kalmia heath in the US is reported to harbor disproportionately large number of rare species. Kalmia heath as a habitat for rare species has not been tested in Canada. The long-term goal of my research program is to understand the habitat and plant community response to forest disturbance particularly the interactions between the dominant understory and canopy species. I frame my applied research questions into contemporary broader ecological concepts. In the next five years I shall concentrate on four short-term objectives: 1) to test the biophysical property of post-fire seedbed and their habitat filtering thresholds, 2) to determine if post-fire Kalmia heath has distinct growth phases with characteristic species composition including rare plants, 3) to determine the population biology of Kalmia and longevity of Kalmia heath, and 4) to test plant-soil feedback effects of Kalmia and even-aged black spruce on community structure. This research will discover the significance of seedbed filter and priority effect on secondary succession in the boreal forest with ericaceous understory. It will create new knowledge on longevity of Kalmia heath which has significant land management implications in eastern Canada.