The Linnean Society of New South Wales

This talk will cover some of the issues, cases and on going challenges Australia faces in relation to environmental lead contamination. While one might have thought the 'lead issue' was all but over following the removal of lead from petrol and paint, nothing could be further from the truth. The likely lowering of acceptable blood lead exposures has raised the bar with respect to the management and response to lead incidents. However, these are not isolated issues as there remains a multitude of historic, ongoing and potential future examples of where either our knowledge is inadequate or the authorities care too little to take effective action. While environmental lead exposure is the primary topic of the talk, other relevant pollutants will be considered. The general two paradigms reign supreme: (i) no data no problem; (ii) the solution to pollution is dilution.

 Top predators often have positive effects on biological diversity owing to their key functional roles in regulating trophic cascades and other ecological processes. Their loss has been identified as a major factor contributing to the decline of biodiversity in both aquatic and terrestrial systems. Consequently, restoring and maintaining the ecological function of top-order predators is a critical global imperative. The dingo is Australia’s largest terrestrial predator. Their status is ambiguous owing to their relatively recent arrival on the continent, the damage they cause to livestock and their role as ecosystem architects. In this talk I will discuss the status and ecological role of dingoes, focusing particularly, on the strong regulatory effects they have on Australian ecosystems. A large body of research now indicates that dingoes regulate ecological cascades, particularly in arid Australia, and that the removal of dingoes results in an increase in the abundances and impacts of herbivores and an invasive mesopredator, the red fox. The loss of dingoes has been linked to widespread losses of small and medium-sized native mammals and the depletion of plant biomass due to the effects of irrupting herbivore populations and increased predation rates by red foxes.

Unicellular organisms belonging to the bacterial and archaeal domains of life are influential in ways that most people never imagine. They are the oldest and most abundant inhabitants of the Earth and have been influencing the biogeochemistry of the planet long before heavy handed humans got in on the game. In this presentation three examples will be given of how the activity of microbes can be exploited to ameliorate some of the negative environmental impacts of human activity. The first example will discuss the ability of bacteria to break down common groundwater pollutants such as those under the Botany Industrial Park, Sydney. The second example will detail the ability of archaea to generate natural gas from renewable feedstock such as food waste, as illustrated by the EarthPower facility in Camellia, Sydney. The third example will describe the inner workings of a sewage treatment plant the likes upon which human civilisation is dependent, using a facility in St Mary's, Sydney. The overall goal of the presentation is to communicate the importance and utility of microbes (and microbiologists!) for continuing human occupancy of the planet.