Associate Professor John Tibby
My research focuses on two main areas that are outlined more fully under "research." These are:
1. Understanding past climatic and environmental variability and change by examining indicators laid down in lake sediments
2. Using diatoms - a type of aquatic algae - to assess stream ”health”
My work involves multiple investigators and often involves collaboration with government agencies in either Queensland or South Australia. The bulk of this work is undertaken along with, or by, PhD students and descriptions of their research appear at the bottom of the "My Research" tab.
My primary research focus is the environmental history of south-east Queensland by examining lake sediment records from North Stradbroke Island/Minjerribah and, to a lesser extent, Fraser Island/K'Gari. Other work, including that of PhD students, is described below.
The North Stradbroke Island research was supported by ARC Linkage project (LP0990124) and ARC Discovery project (DP150103875). The main aims of this work are to i) understand the Holocene climate history of south-east Queensland and ii) understand the long-term environmental in the region. In relation to ii) we are developing ~100,000-year long climate records that are independent of changes in catchment hydrology. These will be compared to pollen-based records of vegetation change and Sporomiella as a record of the presence of megaherbivores.
The original collaborators on DP150103875 were Dr Cameron Barr (postdoctoral fellow), Professor Melanie Leng (Nottingham), Associate Professor Patrick Moss (Queensland), Dr Jeremy Shakun (Boston), Associate Professor Nigel Spooner (Adelaide) and Drs Jon Marshall and Glenn McGregor (Queensland Department of Science, Information Technology, Innovation). The project “team” now includes: Dr Andrew Henderson (Newcastle, UK: on stable isotopes), Patricia Gadd (ANSTO: micro XRF core scanning) and Dr Francesca McInerney (Adelaide: compound specific H isotopes), Dr Lee Arnold (Adelaide-OSL geochronology), Chris Kemp, Haidee Cadd and Richard Lewis (Adelaide PhD students: who are variously working on pollen analysis, C and N isotope records, geochronology and inferences of aeolian transport).
I am working with Dr Cameron Barr and a number of colleagues on the Holocene climate history of south-east Queensland. We are using a recently published rainfall-carbon isotope relationship in Melaleuca quinquenervia leaves (Tibby et al. 2016) to develop a history of rainfall from leaves laid down in Swallow Lagoon, NSI. This relationship is being applied by PhD student Jacinta Greer (principal supervisor Francesca McInerney) to two c. 1,000 year periods in the Holocene. Cameron Barr has developed a ~ 7,500 year long rainfall record from the same site. PhD student, Charlie Maxson will be developing oxygen isotope records from Blue Lake and is co-supervised by Jonathan Tyler (Adelaide) and Melanie Leng (Nottingham).
My other projects include:
The environmental history of the lower Murray River lakes (Lake Alexandrina and Lake Albert) and The Coorong. This work focuses on understanding the natural salinity regime of these internationally significant wetlands. Our ongoing work from Lake Alexandrina aims to infer the natural flow history of the River Murray.
Analysis of diatoms in the streams of south-east South Australia, with the aim of improving water quality guidelines for South Australia (for more details see johntibby.wordpress.com). The project is in collaboration with the Environment Protection Authority (SA) and mostly involves sampling via artificial substrates (rope).
Using diatoms to infer the environmental history of the Naracoorte Caves in collaboration with Dr Liz Reed, Dr Lee Arnold, Associate Professor Nigel Spooner (Adelaide) and many others. Honours student Giddens is examined the relationship between diatom composition and light, moisture and other variables in the caves and on the surrounding soils. Rianna also examined the diatoms from Blanche Cave, while I have examined the record from Bat Cave.
Analysis of diatom-water quality relationships on Cape York Peninsula for the Department of Science, Information Technology, Innovation and the Arts (Qld). This project aims to better understand the influence of water quality on the biota in springs on Cape York. This will ultimately contribute to water resource planning on The Cape.
The investigation of rates of sedimentation in waterholes in the Moonie River (south-west Queensland) and the environmental history of Burdekin River wetlands. These projects are funded by, and conducted in collaboration with Queensland's Department of Science, Information Technology, Innovation and the Arts.
The environmental history of western Victorian lakes (in particular Lake Surprise and Tower Hill) in collaboration with Cameron Barr, Jonathan Tyler, Chris Turney, Peter Kershaw and many others. PhD student Georgina Falster had published a study on the climate history of the late glacial (30,000-10,000 years ago), see Falster et al. (2018) in publications.
Consulting and contract research
Over the decade consultancy projects have been undertaken for many clients. These have mainly focused on analysing the effect of mine drainage and waste water discharge on stream algal communities. Please contact me for pricing.
PhD students' project descriptions. Below are descriptions of PhD students' projects written by the students.
Rachel Rudd – Late Holocene Antarctic climate variability
My research aims to reconstruct changes in climate from Antarctic lake sediments through the use of diatom paleoecology and stable isotope geochemistry. Lakes along the Antarctic coastline are exposed to the atmosphere during summer months and offer a complementary record of climate to the extensively studied ice core archives from the interior of the southern continent. It is anticipated that highly resolved records of variability from these lakes will provide insight into the impact of southern hemisphere climate cycles on the Antarctic coastline – a region currently of great interest due to questions surrounding ice sheet stability and glacial melt.
In order to add to the knowledge of diatom ecology in the region and to make more informed interpretations of the paleo record, a modern study of diatom ecology was conducted as part of the 59th Japanese Antarctic Research Expedition in the 2017/2018 Austral summer. Samples are currently being studied to assess diatom associations with substrate, water chemistry and light attenuation within a range of lakes in Lützow-Holm Bay. These will be used in conjunction with two 3000 year records currently under construction, which are the highest resolution of those within the region in order to detect decadal to centennial scale variability.
Rudd R. C., Tyler J. J., Tibby J., Yokoyama Y., Tavernier I., Verleyen E., Fukui M. & Takano Y. 2016. A diatom-inferred record of lake variability during the last 900 years in Lützow–Holm Bay, East Antarctica. Journal of Quaternary Science, 31, 114-125.
Chris Kemp – Australian climate during human occupation and the last two interglacials
Marine isotope stage 5 and stage 7 (MIS5 and MIS7) are the last periods in Earth’s history when sea level was high and the global climate was generally warm and wet, like today. However, the climate conditions in Australia during these two periods are little understood due to lack of data. Understanding what climate changes occurred in Australia during these periods and how Australian flora reacted to those changes both helps the understanding of large-scale climate drivers and may guide projections of future climate change.
To investigate past climate change during MIS5 and MIS7, a new set of cores from Fern Gully Lagoon wetland on North Stradbroke Island were recovered in 2015 and dated to ~205,000 in age. These cores are being studied using micro-XRF ITRAX systems, charcoal flux and pollen analysis detailing past island fire events and plant varieties. Comparison of local dust flux (from ITRAX, LOI, and magnetic susceptibility), charcoal flux (both micro and macro charcoal) and vegetation show broad coherence.
Planned publications will focus on MIS5 and MIS7 comparisons with changes in local dust flux and its drivers, a multi-proxy study of late MIS7/early and a comparison between the MIS1, MIS5 and MIS7 interglacials.
One publication has already been submitted, reviewing Australian hydroclimate during MIS3
Georgy Falster: Assessing climate variability in south-eastern Australia during the late Quaternary
I study how the climate in south-eastern Australia has varied during the past 30,000 years, and the relationship of this variability with global climate change. I also investigate how we can reconstruct temporal change in various climate variables. My research helps us to better understand the long-term drivers of the south-east Australian climate.
Climate variables – including temperature and rainfall – affect natural materials in different ways, and these materials may be preserved in reservoirs such as lakes and caves. Through analysis of accumulated sediment, we can reconstruct how these climate variables changed through time. My research involves performing geochemical analyses on sediment that has been preserved in lakes and caves. The analyses that I have used include stable isotope analysis of carbonate minerals and organic matter, clumped isotope analysis of snail shells, x-ray fluorescence, x-ray diffraction, scanning electron microscope imaging of sediment, and radiocarbon dating of pollen preserved in the sediment. These techniques allow me to infer climate changes that might have brought about the geochemical variability. I also use statistical analyses to objectively characterise how the sediment has changed through time, and also to compare the changes at one site with other regional locations.
I have two papers currently in review: the first is a collaborative effort, involving researchers from different backgrounds and institutions. The paper presents a new, well dated, high-resolution palaeoclimate record from Lake Surprise, in south-western Victoria. We also use advanced statistical methods to interpret the results in the context of several other high-resolution records from the region. The second is a methodological paper, investigating confounding effects of a) organic matter, and b) different oxidative pre-treatment methods on stable isotope determinations on fine-grained carbonate. In the paper, I suggest optimal parameters for the reduction of organic matter content prior to stable isotope analysis.
Jacinta Skye Greer: Holocene Palaeoclimate Reconstruction for South-East Queensland Derived from Isotopic Signatures of Sub-fossil Leaves.
This project aims to use the isotopic signatures preserved in Melaleuca quinquenervia leaves to reconstruct the changes in rainfall patterns since the initiation of the modern ENSO system during the middle Holocene. This project will also contribute to the understanding of how early diagenesis and chemical analysis affects the isotopic composition of subfossil leaves preserved in an anoxic lake environment. This will provide a new perspective on the middle-late Holocene ENSO system and a sub-tropical Australian perspective which climate states were dominant over this time frame. This research will also produce Australia’s only high-resolution, quantitative rainfall record covering the late Holocene.
Assessment of cellulose extraction techniques has been conducted, identifying which technique is best for isolating the δ18O signal preserved within M. quinquenervia leaf cellulose. The δ18O signal will be compared to instrumental data to determine its relationship to the local climate, and it will then be used to corroborate recent rainfall reconstructions based on the δ13C of M. quinquenervia bulk leaf matter. This palaeoclimate proxy will also be verified through an ongoing field study which will examine the effects of the early stages of diagenesis on M. quinquenervia leaves and the isotopes preserved within.
Greer JS, McInerney FA, Vann DR, Song X. Evaluating methods for extraction of α‐cellulose from leaves of Melaleuca quinquenervia for stable carbon and oxygen isotope analysis. Rapid Commun Mass Spectrom. 2018;32:711–720. https://doi.org/10.1002/rcm.8085
|2018||Associate Professor||University of Adelaide|
|2007 - 2017||Senior Lecturer||University of Adelaide|
|1992||Monash University||Australia||BA (1st class Hons)|
John Tibby led an ARC Discovery project “A 140,000 year insight into the imprint of climate and humans on Australia” (2015-2017).
GEOG 1102 - Footprints on a Fragile Planet
GEOG 2142 - Climate Change (with Douglas Bardsley)
|Date||Role||Research Topic||Program||Degree Type||Student Load||Student Name|
|2018||Principal Supervisor||The Hydroclimatic History of Subtropical Australia Inferred for North Stradbroke Island Lake Sediments||Doctor of Philosophy under a Jointly-awarded Degree Agreement with||Doctorate||Full Time||Mr Charles Reynolds Maxson IV|
|2017||Co-Supervisor||Integrating energy and climate policies; strengthening adoption capacities in the Himalayan Mountains.||Doctor of Philosophy||Doctorate||Full Time||Mr Govinda Pathak|
|2017||Co-Supervisor||Chronostratigraphic framework of SE Queensland supporting interpretation of regional climate dynamics since the last interglacial period, encompassing human arrival and Megafaunal extinction||Doctor of Philosophy||Doctorate||Full Time||Mr Richard John Lewis|
|2016||Principal Supervisor||Human Arrival and Environmental Change||Doctor of Philosophy||Doctorate||Full Time||Miss Haidee Rochelle Cadd|
|2016||Co-Supervisor||Holocene Palaeo Climate Reconstruction for South East Queensland derived from Isotopic Signatures of sub fossil leaves||Doctor of Philosophy||Doctorate||Full Time||Ms Jacinta Skye Bannerman Greer|
|2016||Co-Supervisor||Predictive Modelling of Stream Health of the Torrens and Onkaparinga Catchments||Doctor of Philosophy||Doctorate||Full Time||Ms Jawairia Sultana|
|2015||Co-Supervisor||A Quantitative Assessment of Climate Variability in Southern Australia During the Last Glacial-Interglacial Transition||Doctor of Philosophy||Doctorate||Part Time||Georgina Maja Falster|
|2015||Co-Supervisor||Analysing Antarctic Lake sediments for climate reconstruction||Doctor of Philosophy||Doctorate||Full Time||Miss Rachel Claire Rudd|
|2015||Principal Supervisor||Climate analysis of Australian interglacials MIS7 and MIS5||Doctor of Philosophy||Doctorate||Full Time||Mr Christopher Wilde Kemp|
|Date||Role||Research Topic||Program||Degree Type||Student Load||Student Name|
|2008 - 2013||Co-Supervisor||Coastal Vulnerability and Climate Change in Australia Public Risk Perceptions and Adaptation to Climate Change in Non Metropolitan Coastal Communities||Doctor of Philosophy||Doctorate||Part Time||Mr Christopher David Button|
|2003 - 2010||Co-Supervisor||Droughts and Flooding Rains: A Fine-Resolution Reconstruction of Climatic Variability in Western Victoria, Australia, over the Last 1500 Years||Doctor of Philosophy||Doctorate||Full Time||Dr Cameron Barr|