The Physiological Ecology of Plants to Soil Pyrogenic Carbon
Fire is arguably the most important natural disturbance agent in global forests and grasslands, driving plant community dynamics and ecosystem processes. Empirical evidence and predictive climate models alike indicate an increase in both the frequency and intensity of fires. In turn, soil pyrogenic carbon (PyC) now represents ~15% of the global soil organic carbon pool. Physiological adaptations that enable rapid growth in pioneers (e.g., high rates of photosynthesis) should be advantageous in soils with PyC since plants with a capacity for quick resource capture can capitalize on resource pulses from leachable mineral elements. How pyrogenic carbon influences the ecophysiology of plants, however, remains largely unknown; and is, therefore, the focus of my current Ph.D. research with Sean Thomas at the University of Toronto.
This work has been among the first to demonstrate that PyC influences the performance of early successional temperate old-field pioneers: increasing biomass, photosynthesis, and water use efficiency, but with high species-specific variation (Gale et al. 2016, 2017). We quantitatively described, for the first time, that physiological and functional responses to PyC are dose-dependent and follow unimodal forms (Gale et al. 2019). Census work I conducted in regenerating Pinus banksiana stands of the northern extent of the Canadian boreal following a stand-replacing fire, revealed correlations between soil PyC content and functional traits, suggesting that PyC facilitates re-vegetation in systems prone to frequent and intense fires (In prep).