The web of arid life: biotic and abiotic interactions in a changing world.

Below is my abstract and slides for the Ecological Society of Australia annual conference. My talk is a summary of the last three years on my PhD work. This year we are in Alice Springs, central Australia. More information on the conference can be found here.

Interactions are important in driving the composition and functioning of ecological assemblages and in maintaining diversity. How both biotic and abiotic interactions drive assemblages are fundamental questions in ecology, but complex systems with multiple species are difficult to study. Climate is a major abiotic driver for species in central Australia and the central desert regions are not immune from climate change, with higher temperatures and an increase in the frequency and magnitude of extreme rainfall events already recorded over the last 100 years. Wildfire return intervals are also predicted to decrease from climate change, making it imperative that we understand how both biotic and abiotic interactions shape ecological systems.

Here we use structural equation modelling to integrate remote camera trapping and live-trapping of vertebrates with long term (>15 years) vegetation data from the Simpson Desert to investigate interactions between the biota and with rainfall and fire. We then use these models to predict how changes in rainfall and wildfire events, in-line with future climate scenarios, will permeate up the trophic levels and interact with top-down effects from mammalian carnivores during both boom and bust resources periods in central Australia.

More information:

Greenville A. C., Wardle G. M., Dickman Christopher R. (2012). Extreme climatic events drive mammal irruptions: regression analysis of 100-year trends in desert rainfall and temperature. Ecology and Evolution, 2, 2645-2658.

Greenville A. C., Dickman C. R., Wardle G. M. & Letnic M. (2009). The fire history of an arid grassland: the influence of antecedent rainfall and ENSO. International Journal of Wildland Fire, 18, 631-639.

Greenville A. C., Wardle GM, Tamayo B, Dickman CR (2014). Bottom-up and top-down processes interact to modify intraguild interactions in resource-pulse environments. Oecologia, 1-10.

Greenville, A.C., Wardle, G.M. and Dickman, C.R. (2013). Extreme rainfall events predict irruptions of rat plagues in central Australia. Austral Ecology, 38, 754–764.

Popular science articles:

Of mice and dogs

Predicting rat plagues in the heart of the continent

More on population dynamics of small mammals:

EcoTas 2013: Spatial and temporal synchrony in small mammal populations