Dr Talitha Santini

Senior Lecturer in Envm Mgmnt

School of Earth and Environmental Sciences
Faculty of Science
t.santini@uq.edu.au
+61 7 336 56082

Overview

After completing a postdoctoral fellowship at McMaster University in 2013, Dr Talitha Santini commenced as a Lecturer in Environmental Management in Mining at the University of Queensland, where she holds a joint appointment across the School of Geography, Planning, and Environmental Management, and the Centre for Mined Land Rehabilitation. Dr Santini's research focusses on the rehabilitation of mine sites, tailings, and soils impacted by mining and refining activities, as well as 'extreme' soils derived from natural processes (salinised farmlands, acid sulfate soils). Her key areas of interest include geochemistry, mineralogy, microbiology, and the overlaps between these areas (geomicrobiology). As a soil scientist, Dr Santini is interested in mine wastes and tailings as novel soil parent materials, and compares soil formation processes to those observed in natural systems to identify opportunities for improvement of current rehabilitation practices.

Research Interests

  • Land rehabilitation and management of mine wastes
    Mining is a major contributor to the Australian economy, and careful management is required to balance the benefits of resource extraction against potential environmental impacts. My research in this area focusses on land-based impacts, examining the efficacy of rehabilitation strategies applied within mine sites and within tailings storage areas in addressing issues such as extremes of pH, high salinity, poor structure, and nutrient deficiencies/metal toxicities, and identifying opportunities to improve current rehabilitation practices.
  • Geomicrobiology and microbial ecology
    Soils can harbor highly diverse microbial populations that play key roles in nutrient cycling, soil weathering, and development of soil structure. Modern DNA and RNA sequencing tools (metagenomic and metatranscriptomic approaches) that enable culture-independent analysis of microbial communities now allow us to link the structure, diversity, and functional capacity of microbial communities (often at genus or even species level) to environmental conditions such as soil pH, salinity, aeration, temperature, and nutrient availability. Elucidating the links between environmental conditions and microbial community structure and function may contribute to improved land management practices, particularly in degraded or extreme environments. My research in this area primarily focusses on microbial community development in tailings and mine wastes; however, I also work in other degraded and extreme environments (agricultural lands impacted by secondary salinity, salt/soda lakes, acid sulfate soils) as natural analogues of mining environments, and to identify common processes across these natural and engineered systems.
  • Soil formation and development in natural and engineered systems
    In natural systems, soil formation is typically a process that occurs over geological timescales; however, in engineered systems such as mine sites and tailings facilities, soil formation and development occurs much more rapidly (<100 years). Materials present in engineered landscapes are far from equilibrium with soils in the surrounding environments, due to their extreme chemical (very low or very high pH, high salinity), physical (structureless, very fine or very coarse-grained), and biological (low diversity, limited functional capacity) properties, and these materials weather rapidly during exposure to natural processes such as rainfall percolation and atmospheric oxidation and carbonation. Natural weathering processes may be assisted by amendments which target key thresholds in soil formation processes to accelerate remediation progress, and allow the engineered landscape to support a vegetation cover or other end land use in a shorter timeframe. My research focusses on the evaluation of soil formation in mine wastes and tailings, and identification of likely pedogenic trajectories in response to natural weathering processes and applied amendments. I also compare soil formation processes and soil features in engineered systems with those occurring in natural, analogous systems (e.g. Ferralsols, in the case of bauxite residue).
  • Soil mineralogy
    In both natural and engineered systems, the mineral assemblages present in soil strongly influence soil chemical, physical, and biological properties; however, quantification of mineral concentrations is often hindered by the variety of minerals present in any one sample (typically >10), and structural imperfections in the crystal lattices of these minerals. I use the Rietveld refinement technique in my research to quantify mineral concentrations in soil samples based on X-ray diffraction patterns, which enables quantification of mineral concentrations in complex samples. My interest in soil mineralogy ties in with evaluation of soil formation (identifying horizons based on changes in mineralogy with depth; tracking dissolution and precipitation of minerals over time), rehabilitation efficacy (linking changes in mineralogy to applied amendments and weathering), and geomicrobiology (identifying influence of microorganisms on mineral precipitation and dissolution processes).

Qualifications

  • Doctor of Philosophy, The University of Western Australia

Publications

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Grants

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Supervision

  • Doctor Philosophy

  • Doctor Philosophy

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Publications

Book

Journal Article

Conference Publication

Grants (Administered at UQ)

PhD and MPhil Supervision

Current Supervision

  • Doctor Philosophy — Principal Advisor

  • Doctor Philosophy — Associate Advisor

    Other advisors:

Possible Research Projects

Note for students: The possible research projects listed on this page may not be comprehensive or up to date. Always feel free to contact the staff for more information, and also with your own research ideas.