Thursday, April 1
S203, 3:30-4:30

Dr. Cameron Carlyle, Dept. of Botany, UBC will present a talk on “Interacting effects of climate change and disturbance on BC Interior grasslands”.

Abstract: Considering that half of the terrestrial land mass is grazed and that climate change has the potential to impact grassland composition and function it is important to understand the interaction between grazing and climate-induced changes in grassland ecosystems.

We expected that community resistance to climate-induced stress and disturbance would decrease with increasing productivity in temperate grasslands in the southern interior of British Columbia, Canada. We ran a four year factorial experiment testing the interacting effects of warming (ambient or increased), water availability (ambient, reduced, increased), and clipping (clipped or unclipped) and repeated it at three points along a natural productivity gradient. Clipping had the largest effect on community composition and function and affected plant communities across the gradient. The effect of temperature was minimal although it did reduce species richness at some locations, while the response to water manipulations varied unexpectedly across the gradient.

Contrary to our expectations, low productivity grasslands were most responsive to change, while high productivity grasslands had a small response. Our results suggest that climate warming and disturbance can alter plant community function and composition in relatively short time periods, and that vegetation response varies across a productivity gradient.