Phenology & Climate Change
Species composition is a key determinant of grassland ecosystem function and resilience. Climate change is predicted to alter the distribution of cool season (C3) and warm season (C4) grasses, however, the lack of spatial distributions and temporal variations of grass functional type information severely limits our understanding of climate impacts on grasslands.
In collaboration with scientists across Australia including Australian Research Council Laureate Distinguished Professor Belinda Medlyn and Professor Sally Power at Western Sydney University, A/Prof Paul Beggs at Macquarie University, Professor Janet Davis at Queensland University of Technology, Dr Danielle E Medek at The Prince Charles Hospital, Dr Christopher Hall and Distinguished professor Alfredo Huete at University of Technolgogy Sydney, we designed an algorithm to discriminate C3 and C4 grasses using phenology information, and for the first time, mapped annual distributions of C3 and C4 grasses in Australia. The maps then enabled us to track grass composition changes in time and space, and their association with climate change.
Our results revealed a devastating shift towards increasing C4 grasses. Counterintuitively, our climate analysis showed that this shift was primarily associated with seasonal rainfall patterns rather than warming. Our research suggests increased attention to water is needed in ecosystem and climate change research.
Selected Publications:
Xie, Qiaoyun, et al. "Satellite-observed shifts in C3/C4 abundance in Australian grasslands are associated with rainfall patterns." Remote Sensing of Environment 273 (2022): 112983. https://doi.org/10.1016/j.rse.2022.112983
