PhD Candidate: Chaminda Alahakoon

PhD Supervisors: Associate Professor Paul Rymer (WSU), Associate Professor Rachael Nolan (WSU), Associate Professor Mark Ooi (UNSW), Dr Cathy Offord (Australian Plant Bank, BGS)

Project Summary: Seedling recruitment is a vital process in plant regeneration. There is a significant knowledge gap on how climate change in particular temperature and water availability affect seedling establishment and success leading to an uncertainty in resilience of remnant native ecosystems as well as the outcomes of restoration efforts. 

We have been conducting laboratory experiments to understand the temperature and water requirements for the germination of native species in the Cumberland Plain, with the aim of identifying species at risk and informing future restoration and management efforts.

However, to apply our findings to field conditions, we need to validate the thermal-time and hydro-time model outcomes from the laboratory experiments to determine which species exhibit greater seedling recruitment in different parts of the landscape. Microhabitat factors influence the exposure of seeds and seedlings to temperature and water availability, contributing to their establishment in the field. Predictive models of seedling recruitment must incorporate mechanistic responses to both broad and microclimatic conditions to provide reliable estimates of population growth or decline, now and into the future.

The proposed study aims to investigate the interactive effects of regional climate, canopy cover and leaf litter on seedling emergence and survival of native species in the Cumberland Plain Woodlands. Importantly the outcomes of this field experiment will optimize predictions for future conservation and restoration efforts in the Cumberland subregion with broad implications across Australia.