Does differential nutrient-use efficiency among species explain trends in the canopy composition of Tasmanian rainforests?
In Tasmania, Nothofagus cunninghamii forms monodominant rainforests on relatively fertile soils in lowland areas, but declines in abundance on infertile soils. On infertile soils, species such as Eucryphia lucida and Phyllocladus aspleniifolius increase in abundance. The capacity of the latter species to dominate rainforests on infertile soils is related to superior growth rates under these conditions, compared with N. cunninghamii. This project will investigate whether E. lucida and P. aspleniifolius have high plant-level nutrient-use efficiency (NUE), i.e. the capacity to grow more per unit nutrient uptake, and the mechanisms that contribute to NUE. This project would involve growing seedlings of the main canopy species on high-nutrient and low-nutrient soils and measuring various aspects of plant performance (photosynthesis, growth and morphology). Another similar project is available that focuses on a different group of plant species.
