Listen to Margie Mayfield talk about her research into plant communities

Listen to the podcast from Margie Mayfield’s seminar on 17 April about plant communities in a changing world.

The Environment Institute’s Global Ecology Laboratory presented Dr Margie Mayfield, Senior Lecturer in Plant Ecology at the University of Queensland on Wednesday 17 April 2013. Her research broadly focuses on how plant and insect communities reassemble, persist and function following human land-use change.

ABSTRACT

Human activities are increasingly driving the development of novel plant communities worldwide. These stable mixes of resident native, range-expanded native and exotic plant species have become more common than most truly “natural” plant communities in many areas. Interestingly, novel communities are often interspersed with much more severally degraded communities (all exotics) and areas that support largely native communities. This begs the question, why do novel communities form in some places but not others? Despite the increasing commonality of novel communities and their potential role in conservation, we have a poor understanding of how these communities differ from those they replace and what drives and prevents their assembly. Identifying drivers of novel community development is increasingly important for many conservation and restoration efforts. In this talk I will discuss the theoretical expectations of how we expect communities to change in response large-scale environmental change and what processes should mediate where and when native-dominated communities should be resilient or susceptible to novel community development. I will then discuss several of the projects coming out of my lab looking at novel community assembly in the York Gum woodlands of SW Western Australia, where my group has been studying the mechanisms of novel community assembly over the last several years. Specifically, I will discuss the role of biotic interactions in mediating community wide responses to land use change and species invasions across environmental gradients.

Download the podcast from this seminar.

 

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The Carbon Key seminar recording on carbon levels and evolution now available

Recently, Environment Institute member Professor Martin Kennedy presented a seminar as part of the University of Adelaide’s Research Tuesdays Seminar Series entitled The Carbon Key.

The Carbon Key outlined the relationship between carbon levels and the evolution and stability of complex life, and how understanding this relationship is allowing more accurate predictions of future change.

The video from the seminar can now be streamed on the University of Adelaide’s live stream website.

View the video here.

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Guest Speaker Paul Ehrlich podcast now available

The podcast for the presentation by Professor Paul Ehrlich is now available for download.

Prof. Paul R. Ehrlich

The Environment Institute and the Fenner School of Environment and Society at the Australian National University presented Professor Paul Ehrlich, Bing Professor of Population Studies in the department of Biological Sciences at Stanford University on Thursday 21 March 2013 in Canberra.

The presentation Avoiding a collapse of civilisation – our chances, prospects and pathways forward discussed population growth and its effect on the environment.

Paul Ehrlich is the Bing Professor of Population Studies in the department of Biological Sciences at Stanford University, president of Stanford’s Centre for Conservation Biology and Adjunct Professor, University of Technology, Sydney. By training he is an entomologist specializing in Lepidoptera (butterflies), but he is also a prominent ecologist and demographer. Ehrlich is best known for his dire warnings about population growth and limited resources. He became well-known after publication of his controversial 1968 book The Population Bomb.

Listen to the presentation.

ABSTRACT

Environmental problems have contributed to numerous collapses of civilizations in the past. Now, for the first time, a global collapse appears possible and at the same time avoidable. Population growth supercharged by significantly increasing consumption interacting with our choices of technologies are major drivers. Dramatic cultural change provides the main hope of averting calamity.

Paul and Anne Ehrlich have written a paper on how humanity’s global civilisation is threatened with collapse by an array of environmental problems. In this special presentation, Professor Ehrlich gave a talk about his recent conclusions.

Professor Ehrlich was  joined by leading ecological scientists to participate in an in-depth panel discussion. The panel extended and discussed Professor Ehrlich’s topics as they relate to sustainability politics in Australia, broaching controversial topics from food and energy supply to the politics of greed. How much scientific evidence underlies our national decision-making?

The panel included Professor Corey Bradshaw from the Environment Institute, Professor David Lindenmayer from ANU, and Professor Graham Pyke from University of Technology Sydney. Professor Stephen Dovers, Director of the Fenner School of Environment, chaired the panel session.

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Listen to Merinda Nash talk about her research into the effects of ocean acidification on tropical red algae and the discovery of dolomite.

Listen to the podcast from the recent seminar by Merinda Nash.

The Environment Institute’s Sprigg Geobiology Centre presented Merinda Nash from the Electronic Materials Engineering, Research School of Physics, Australian National University on Thursday 21st February 2013.

The talk was titled ‘Conditions constraining biomineralised dolomite in living tropical calcifying red algae offers insight into past environments’ (See Abstract Below)

Merinda Nash

Merinda Nash is a PhD candidate in the Electronic Materials Engineering group, Research School of Physics, at the Australian National University. Her research is into the physical properties of biogenic carbonates, particularly coral and coralline algae and how these may be impacted by ocean acidification.

 

 

ABSTRACT

Research into effects of ocean acidification on tropical calcifying red algae led to the surprising discovery that these algae precipitate substantial amounts (up to 30% of total carbonate) of dolomite contemporaneously with their living processes. Biomineralised dolomite is found within the cell spaces of living crustose coralline alga and has both rhomb and spheroidal morphologies. Alteration bands of dolomite and aragonite obliterate cell features leaving ghost outlines of original cells. There are many similarities between features of this modern dolomite paleo dolomite. It seems that this bio-dolomite is common in modern coral reefs and is constrained by light, temperature and water energy conditions. Our experiments showed that the presence of dolomite in the coralline algae reduces its rate of dissolution 6-10 times compared to only Mg-calcite coralline algae. This is due to a combination of reduced porosity and stability of the dolomite in-fill. Analysis of reef core coralline algae demonstrated that this bio-dolomite is stable over at least several thousand years and the original cell in-fill morphology is retained. The preferential preservation of dolomite rich red algae demonstrates a process for concentrating dolomite in shallow marine environments in elevated CO2 conditions. Biological ocean acidification experiments on calcifying algae have the potential to answer many questions about how dolomite forms, what is the isotope fractionation of this bio-dolomite and can this information be used to reconstruct past environments. This opens the door to new opportunities for biologists and geologists to collaborate to understand both the past and the future.

Read Merinda’s paper published in Nature that relates to this talk.

Download the podcast from this seminar.

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Guest Speaker: Dr Geert Jan van Oldenborgh – Podcast now available

The podcast for the presntation by Dr Geert Jan van Oldenborgh is now available for download.

The Environment Institute’s Water Research Centre presented Dr Geert Jan van Oldenborgh from the Global Climate Research division of KNMI (Royal Netherlands Meteorological Institute) on Tuesday 22nd January 2013.

Dr Geert Jan van Oldenborgh. Image courtesy of KNMI website

The talk was titled ‘Some examples how and why precipitation means and extremes are changing’ and covered mean precipitation trends, mean precipitation extremes and precipitation events (such as the Thailand floods, hourly precipitation extremes in the Netherlands & Hong Kong and more recent extremes in Manila and Queensalnd).

Dr. Geert Jan van Oldenborgh is senior researcher in the Global Climate Research division of KNMI. He is a climate analyst with a background in statistical analysis of observations, seasonal and decadal forecast verification, and climate event attribution. He combines these by applying seasonal forecast verification techniques to climate model output, verifying whether they are able to reproduce the observed changes. Recently, he used observations and models to consider the role of climate change on the Thailand and Manilla floods. As the author of the KNMI Climate Explorer he makes large amounts of climate observations, analyses and model output available for analysis to the wider climate-interested community. He is Lead Author for the IPCC WG1 AR5 (Chapter 11, Near-term projections and predictability, and Annex I Atlas).

Listen to the presentation.

ABSTRACT

Seasonal and annual mean precipitation trends are fairly well-observed and well-studied. This enables us to compare the observed trends to the trends simulated by the CMIP5 multi-model GCM ensemble used for the IPCC Fifth Assessment Report, using a verification statistic from weather and seasonal forecasting: reliability. It turns out that the mismatch between observed and modelled trends is larger than expected on the basis of natural variability and the spread between the models. The reasons for this are as yet unknown.

In summer 2011 severe flooding occurred in Thailand, a region where modelled and observed trends agree well. An investigation into the causes of these floods showed that no anthropogenic factor could be found in the meteorological aspects: the precipitation was high but not far out of the historical record, and no significant trend to more precipitation could be found in the observations. Climate model simulations covering the same period also showed no trend in mean or variability. However, there were clear anthropogenic factors on the ground that increased the risk of flooding.

Trends in extreme precipitation are harder to study, as good observations are harder to get and models have more problems reproducing extremes. We present one example of hourly precipitation extremes in the Netherlands and Hong Kong. In spite of the differences in climate, both scale exactly the same as a function of dew-point temperature. The rise in extremes in the Netherlands can be attributed to the rise in temperature, and hence global warming. In Hong Kong the increase in extreme hourly precipitation in the rainy season is not related to the mean temperature increase.

Extreme precipitation events on the daily scale also have very different characteristics from seasonal mean extremes. We discuss preliminary results on the recent flooding in Manilla in 2012 and apply the same method to the Queensland floods of 2011 to compare with results of the experts in the audience.

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Guest Speaker: Xavier Lambin – Podcast now available

The podcast from the presentation by Xavier Lambin is now available to download.

The Environment Institute presented Xavier Lambin from the School of Biological Sciences, The University of Aberdeen, UK on Monday 26th November 2012.

Xavier Lambin. Image courtesy of The University of Aberdeen

The talk was titled“Continent -wide dampening of population cycles in keystone herbivores; patterns, likely processes and consequences for predators.”

Download the PowerPoint here.

ABSTRACT
In recent years, evidence has emerged that dramatic changes in ecosystem processes and functioning are taking place across Europe under the joint impact of climate change and human-induced shift in land use. One of the most spectacular changes concerns the dampening in the fluctuations of populations of keystone herbivore species such as voles and moths with cyclical dynamics that took place nearly simultaneously in much of Europe in the 1990s. Changes in small herbivore dynamics have the potential to lead to ecosystem re-organisation and therefore represent a challenge for the conservation of biodiversity. However, there remains much uncertainty on what are the processes responsible for multi-annual cycles, how these might be modified by climate and whether the same set of processes operate in all cyclic vole populations. Furthermore, whether cycle dampening is general, or local, and result from extrinsic environmental changes or from intrinsic process stochasticity is currently unknown.

In this talk, Xavier first presented empirical and modelling developments on the demographic basis for vole cycles based on our long term studies. He then showed how seasonality and the destabilising influences of pathogen host interaction or changes in herbivore-induced changes in plant quality might interact with seasonality in the environment to lead to cyclic dynamics. Next, using the largest compilation of time series of vole abundances yet assembled, Xavier presented new analyses that demonstrate consistent cycle amplitude dampening associated with a reduction in winter vole population growth, and suggesting that regulatory processes responsible for cyclicity have not been lost. The underlying syndrome of change throughout Europe, species and ecosystems suggests a common climatic driver acting over very large scales. Our analyses suggest increasing periods of low amplitude small herbivore population fluctuations are expected in the future, with cascading impacts on trophic webs across ecosystems. Finally, Xavier illustrated the likely impact of changes on prey dynamics on the dynamics of birds of prey using our long terms studies on the demography of Tawny owls.

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‘The geological record of ocean acidification’ Andy Ridgwell – Podcast now available

Download the podcast from Professor Andy Ridgwell’s seminar titled ‘The geological record of ocean acidification.’

The Sprigg Geobiology Centre presented a free public seminar by Dr Andy Ridgwell from the School of Geographical Sciences, University of Bristol , UK on Monday 5th November 2012.

Andy Ridgwell. Photo courtesy of The University of Bristol

Andy Ridgwell is Professor of Earth System Modelling and a Royal Society University Research Fellow in the School of Geographical Sciences, University of Bristol. In this talk Andy addressed the questions: at what rate of atmospheric pCO2 change does ocean acidification become qualitatively similar to current and future changes, and have any events in the geological past exhibited the characteristics of anthropogenic ocean acidification?

Read the full abstract and download the PowerPoint Presentation on the Sprigg Geobiology Centre website.

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‘Four in 40: Catchment to Coast’ podcasts now available

The podcasts from the recent Four in 40 seminar hosted by the Water Research Centre and SA Water are now available to download.

The Four in 40 was titled ‘Catchment to Coast’ and was held on Thursday 25th October 2012 at SA Water house.

Speakers included:

• Peter Pfennig , EPA
• Jacqueline Frizenschaf, Manager Catchments & Land Management, SA Water
• Prof. Sean Connell, School of Earth & Environmental Sciences, Adelaide University
• Milena Fernandes, Senior Marine Scientist, SA Water

Visit the website to download the podcasts.

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Water Wednesday podcasts now available

The podcasts from the Water Research Centre’s final Water Wednesday seminar held on 19 September 2012 are now available to download.

This Water Wednesday forum, titled ‘Optimisation of Urban Water Supply Systems: A Pipe Dream?’ involved three international experts who spoke about recent developments in the optimisation of urban water supply systems and prospects for further developments in this field.

Speakers included:

• Professor Dragan Savic, University of Exeter
• Asst. Professor Dominic Bocelli, University of Cincinnati
• Professor Graeme Dandy, University of Adelaide

Visit the website to download the podcasts.

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Four in 40: More efficient management of water supply infrastructure – Podcast now available

Professor Angus Simpson

The podcast from the most recent “Four in 40″ seminar, presented by The Water Research Centre and SA Water on Thursday 16th August 2012, is now available. The seminar was titled “More effecient management of water supply infrastructure”.

Speakers include:

• Professor Angus Simpson, School of Civil, Environmental & Mining Engineering, University of Adelaide
• Mr Kane Scott, SA Water
• Mr Chris Stokes, School of Civil, Environmental & Mining Engineering, University of Adelaide
• Mr Steve McMichael, SA Water

Download the individual podcasts and accompanying presentations

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