Skip to Content
Southern Cross GeoScience

Professor Scott G. Johnston

Scott Johnston

E: scott.johnston@scu.edu.au
Research Gate Profile

Landscape Hydrogeochemistry Group

Research interests / background

My research explores geochemical and hydrological processes that control water quality and sediment geochemistry and at a landscape-scale.

My research embraces diverse landscapes, ranging from floodplain and estuarine wetlands to head-water streams and spans the mineral-water interface through to sub-catchment scale processes.

I am particularly interested in the co-cycling of major elements (Fe, S, C) and trace elements such as arsenic in aquatic and terrestrial environments with dynamic redox conditions.

I have worked closely with industry, state and local governments to develop and refine a variety of techniques for remediating highly degraded acid sulfate soil wetlands.

Current research topics

Arsenic mobility in the environment:

Arsenic / Iron mineral interactions:

Remediation of acid sulfate soil wetlands:

Coastal floodplain hydrology and biogeochemistry:

Headwater stream geochemistry:

Awards & Honours

  • Australian Research Council Future Fellowship - 2011-2015
  • Australian Research Council APDI Fellowship - 2008

Research grants

Category 1 Grants

ARC

  • $401,000. Australian Research Council Linkage grant (LP160100061). "Maximising carbon sequestration in freshwater wetlands". 2016-2018. (Lead Investigator).
  • $709,212. Australian Research Council Future Fellowship (FT110100130). "Sea-level rise as a driver for arsenic mobilisation: unravelling the fundamental hydro-geochemical controls". 2011-2015
  • $250,000. Australian Research Council Linkage grant (LP120100238). "Unravelling the rhizosphere redox-cycling of iron, sulfur and carbon in re-flooded acidic wetlands". 2012-2014. (Lead Investigator)
  • $320,000. Australian Research Council (LP120200723) "Episodic estuarine hypoxia: resolving the geochemistry of coastal floodplain blackwaters" Sullivan, L. A., Burton, E. D., Rose, A. L., Johnston, S. G., Wong, V., Bush, R. T., and Wood, M.
  • $800,000. Australian Research Council (LE110100174) Innovative synchrotron science - program for access to the Australian National Beamline Facility and cutting-edge beamlines at international synchrotrons 2011-2012.
  • $246,000. ARC grant (LP0882141)and APDI fellowship."Impacts of climate change on coastal floodplain wetland biogeochemistry and surface water quality" (Chief Investigator).
  • ARC LIEF grant (LE140100007 - $330,000) "An integrated facility for the advanced characterisation of environmental particles." 2014. (Chief Investigator).
  • ARC LIEF grant (LE140100023 - $360,000) "Multi-collector inductively coupled plasma mass spectrometer" 2014 (Chief Investigator).
  • ARC LIEF grant (LE150100007 - $170,000) "Metal speciation for complex studies in changing environments" (Chief Investigator)

Other Category 1 Grants

  • $25,850. Australia India Strategic Research Fund (ST060012). "Safe and sustainable use of arsenic contaminated aquifers in the upper Gangetic plain: establishing a multi-disciplinary Australian-Indian collaboration". 2012-2013

Other Grants

  • 64 hrs. Taiwan Synchrotron Light Source (2016-1-026-1) " An XAS K-edge investigation of Fe and As speciation during anoxic incubation of thermally transformedschwertmannite " 2016 (Lead Investigator)
  • 48 hrs. Australian Synchrotron (AS162/XAS/10710) "Resolving the effect of seawater inundation and sulfate reduction on antimony mobility in a contaminated wetland " 2016 (Investigator)
  • 72 hrs. Australian Synchrotron (AS162/XAS/10765) "Antimony mobility in sulfidic environments: an XAS study of antimony sorption to mackinawite (FeS) " 2016 (Investigator)
  • 144 hrs. Taiwan Synchrotron Light Source (2014-2-012-1) "An XAS K-edge investigation of Fe, As and Sb speciation during Fe(II)-catalysed transformation of jarosite" 2014 (Lead Investigator)
  • $25,850. Australia India Strategic Research Fund (ST060012) "Safe and sustainable use of arsenic contaminated aquifers in the upper Gangetic plain: establishing a multi-disciplinary Australian-Indian collaboration". 2012-2013
  • 56 hours. Australian Synchrotron Research Program (AS122/ANBF/5363) "An XAS study of iron mineralogical controls on arsenic mobility during simulated inundation of a contaminated floodplain." 2012 (Investigator).
  • 72 hours. Australian Synchrotron Research Program (AS122/ANBF/4812) "Unravelling the impact of floodplain soil inundation on arsenic mobility: integrated synchrotron XAS and high-resolution pore-water analysis." 2012 (Investigator).
  • $4,665. Australian Synchrotron Research Program (AS122/ANBF/4880) "An XAS study of arsenic reduction and thiolation during long-term anaerobic transformation of arsenic-rich schwertmannite". 2012 (Investigators: Burton E.& Johnston S.).
  • 72 hours. Australian Synchrotron Research Program (AS111/ANBF/3271) "Reductive transformation of As-bearing jarosite by H2S: using Fe, As and S K-edge XAS analysis to resolve a critical reaction pathway." 2011 (Chief Investigator)
  • $11,980. Australian Institute of Nuclear Science and Engineering (ALNGRA6635). "Reductive transformation of jarosite by H2S: determining the role of S mineralisation products on arsenic mobility". 2011 (Chief Investigator)
  • 46 hours. Australian Synchrotron Research Program (AS112/XAS/3685) "Influence of humic acid on the speciation of iron and arsenic in sulfidogenic environments". 2011 (Investigator)
  • 46 hours. Australian Synchrotron Research Program (AS112/XAS/3855) "Unravelling electron flow associated with iron and arsenic biogeochemistry in flooded soil". 2011 (Investigator)
  • $20,000. Environment Trust Seeding, NSW Government Grant. (07/10-06/11) "What lies beneath? A new method to map sub-surface acidity." 2010 (Investigator)
  • 101 hours. Australian Synchrotron Research Program (P2526 2010/2) "The effect of biogenic iron-sulfide formation on arsenic mobility in acid-sulfate wetlands: An integrated arsenic, iron and sulfur K-edge XAS study." 2010 (Investigator).
  • 48 hours. Australian Synchrotron Research Program (P2509 2010/2) "Arsenic sorption to greigite: Using XAS to resolve sorption mechanisms." 2010 (Investigator).
  • $26,000. Taiwan Synchrotron Light Source (2009-1-020-2) "Using X-ray absorption spectroscopy to unravel iron bio-mineralisation pathways in re-flooded acid-sulfate soils" 2009-2010 (Investigator).
  • $14,535. Australian Institute of Nuclear Science and Engineering. "Controls on the reductive dissolution of natural jarosite in a tidally inundated acid sulfate soil wetland". 2010 (Investigator).
  • $12,135. Australian Institute of Nuclear Science and Engineering. "Characterising nano-particulate iron minerals formed in acid sulfate soils following seawater inundation". 2010 (Investigator).

Post Graduate student supervision

PhD

Katy Limpert (current), Jasmine Diwakar (current), Niloofar Karimian (current), Valerie Schoepfer (current), Saina (current)

Masters

Phil Hirst (current)

Honours

Kimberley Warren (current), Belinda Allman (completed), Kelly Fox (completed), Terry Rothnie (completed)

Publications

Journal articles

2017

Karimian, N., Johnston S.G., Burton E.D. (2017) Acidity generation accompanying iron and sulfur transformations during drought simulation of freshwater re-flooded acid sulfate soils. Geoderma, 285, 117-131.

2016

Johnston S.G., Burton E.D., Moon, E.M. (2016) Arsenic mobilization is enhanced by thermal transformation of schwertmannite. Environmental Science and Technology, 50 (15), 8010-8019.

Morgan, B., Johnston S.G., Burton E.D., Hagan R. (2016) Acidic drainage drives anomalous rare earth element signatures in intertidal mangrove sediments. Science of the Total Environment 573, 831-840.

Johnston S.G., Morgan, B., Burton E.D. (2016) Legacy impacts of acid sulfate soil runoff on mangrove sediments: reactive iron accumulation, altered sulfur cycling and trace metal enrichment. Chemical Geology, 427, 43-53.

2015

Johnston S.G., Diwakar J., Burton E.D. (2015) Arsenic solid-phase speciation in an alluvial aquifer system adjacent to the Himalayan forehills, Nepal. Chemical Geology, 419, 55-66.

Johnston S.G., Burton E.D., Hagan R., Aaso T., Tuckerman G. (2015) A revised method for determining existing acidity in re-flooded acid sulfate soils. Applied Geochemistry, 52, 16-22. (2012 ERAID 1892 - FOR 0402)

Johnston S.G., Rose A.L, Burton E.D., Webster-Brown J. (2015) Landslide-induced iron mobilization shapes benthic accumulation of nutrients, trace metals and REE fractionation in an oligotrophic alpine stream. Geochimica et Cosmochimica Acta 148, 1-22. (2012 ERAID 1898 - FOR 0402)

Wong V.N.L., Johnston S.G., Burton E.D., Bush R.T., Sullivan L.A., Slavich, P.G. (2015) Seawater inundation of coastal floodplain sediments: short-term changes in surface water and sediment geochemistry. Chemical Geology, 398, 32-45 (2012 ERAID 1893 - FOR 0402)

2014

Burton E.D., Johnston S.G., Kocar B. (2014) Arsenic mobility during flooding of contaminated soil: the effect of microbial sulfate reduction. Environmental Science and Technology, 48(23), 13660-13667. (2012 ERAID 4669 - FOR MD)

Huang J., Triantafilis J., Wong V.N.L., Nhan T., Johnston S.G., Lark M.R. (2014) Digital soil mapping of a coastal acid sulphate soil landscape. Soil Research, 52: 327-339 (2012 ERA 5248 - FOR MD)

Johnston S.G., Burton E.D., Aaso T., Tuckerman G. (2014) Sulfur, iron and carbon cycling following hydrological restoration of acidic freshwater wetlands. Chemical Geology, 371 9-26. (2012 ERAID 1893 - FOR 0402)

Keene A.F., Johnston S.G., Bush R.T., Burton E.D., Sullivan L.A. Dundon M., McElnea A.E., Smith C.D., Ahern C.R., Powell B. (2014) Enrichment and heterogeneity of trace elements in redox-interfacial coastal sediments Chemical Geology, 383: 1-12. (2012 ERAID 1893 - FOR 0402)

Diwakar J., Johnston S.G., Burton E.D., Shrestha S.D. (2014) Arsenic mobilization in an alluvial aquifer of the Terai region, Nepal. Journal of Hydrology (submitted manuscript)

Johnston S.G., Burton E.D., Hagan, R., Aaso, T., Tuckerman, G. (2014) A revised method for determining existing acidity in re-flooded acid sulfate soils. Applied Geochemistry (submitted manuscript)

Johnston S.G., Rose, A.L, Burton E.D., Webster-Brown, J. (2014) Landslide-induced iron mobilization shapes benthic accumulation of nutrients, trace metals andREE fractionation in an oligotrophic alpine stream. Geochimica et Cosmochimica Acta (submitted manuscript)

2013

Burton E.D., Johnston S.G., Kraal P., Bush R.T., Claff S. (2013) Sulfate availability drives divergent evolution of arsenic speciation during microbially-mediated reductive transformation of schwertmannite. Environmental Science & Technology. 47, 2221 - 2229. (2012 ERAID 4674 - FOR MD)

Burton E.D., Johnston S.G., Planer-Friedrich B. (2013) Coupling of arsenic mobility to sulfur transformations during microbial sulfate reduction in the presence and absence of humic acid. Chemical Geology. 343, 12 - 24 (2012 ERAID 1893 - FOR 0402)

Wong V.N.L., Johnston S.G., Burton E.D., Bush R.T., Sullivan L.A. (2013) Seawater-induced mobilization of trace metals from mackinawite-rich estuarine sediments. Water Research 47, 821 - 832 (2012 ERAID 4694 - FOR MD)

2012

Burton E.D., Johnston S.G. (2012) Impact of silica on the reductive transformation of schwertmannite and the mobilization of arsenic. Geochim. Cosmochim. Acta. 96,135-153. (2012 ERAID 1898 - FOR 0402)

Johnston S.G., Burton E.D., Keene A.F., Planer-Friedrich B., Voegelin A., Blackford M., Lumpkin G. (2012) Arsenic mobilization and iron transformations during sulfidization of As(V)-bearing jarosite. Chemical Geology 334, 9-24 (2012 ERAID 1893 - FOR 0402)

Johnston S.G., Keene A.F., Burton E.D., Bush R.T., Sullivan L.A. (2012) Quantifying alkalinity generating processes in a tidally remediating acidic wetland. Chemical Geology 304-305: 106-116 (2012 ERAID 1893 - FOR 0402)

2011

Burton E.D., Bush R.T., Johnston S.G., Sullivan L.A., Keene A.F. (2011) Sulfur biogeochemical cycling and novel Fe-S mineralization pathways in a tidally re-flooded wetland. Geochimica et Cosmochimica Acta 75, 3434-3451 (2010 ERA ranking A*).

Burton E.D., Johnston S.G., Bush R.T. (2011) Microbial sulfidogenesis in ferrihydrite-rich environments: effects on iron mineralogy and arsenic mobility. Geochimica et Cosmochimica Acta 75, 3072-3087(2010 ERA ranking A*).

Claff S.R., Sullivan L.A., Burton E.D., Bush R.T. Johnston, S.G. (In press). Partitioning of metals in a degraded acid sulfate soil landscape; influence of tidal re-inundation. Accepted manuscript., Chemosphere. (2010 ERA Ranking A).

Johnston S.G., Keene A.F., Bush R.T., Sullivan L.A., Wong V.N.L. (2011) Tidally driven water column hydro-geochemistry in a remediating acidic wetland. Journal of Hydrology 409, 128-139 (2010 ERA ranking A*).

Johnston S.G., Keene A.F., Burton E.D., Bush R.T., Sullivan L.A. (2011) Iron and arsenic cycling in intertidal surface sediments during wetland remediation. Environmental Science and Technology 45 (6), 2179-2185 (2010 ERA Ranking A*)

Johnston S.G., Keene A.F., Bush R.T., Burton E.D., Sullivan L.A., Isaacson L.S., McElnea A.E., Ahern C.R., Smith C.D., Powell B. (2011) Iron geochemical zonation in a tidally inundated acid sulfate soil wetland. Chemical Geology 280, 257-270. (2010 ERA ranking A*).

Keene A.F., Johnston S.G., Bush R.T., Sullivan L.A., Burton E.D., McElnea A.E., Ahern C.R., Powell B. (2011) Effects of hyper-enriched reactive Fe on sulfidisation in a tidally inundated acid sulfate soil wetland. Biogeochemistry 103, 263-279(2010 ERA ranking A).

Wong V.N.L., Johnston S.G., Burton E.D., Bush R.T., Sullivan L.A., Slavich P.G. (2011) Anthropogenic forcing of estuarine hypoxic events in sub-tropical catchments: Landscape drivers and biogeochemical processes. Science of the Total Environment 409, 5368-5375(2010 ERA ranking A).

2010

Burton E.D., Johnston S.G., Watling K., Bush R.T., Keene A.F., Sullivan L.A. (2010) Arsenic effects and behaviour in association with the Fe(II)-catalysed transformation of schwertmannite. Environmental Science and Technology, 44 (6), 2016-2021. (2010 ERA ranking A*)

Johnston S.G., Burton E.D., Bush R.T., Keene A.F., Sullivan L.A., Smith D., McElnea A.E., Ahern C.R., Powell B. (2010) Abundance and fractionation of Al, Fe and trace metals following tidal inundation of a tropical acid sulfate soil. Applied Geochemistry, 25, 323-335. (2010 ERA ranking B)

Johnston S.G., Keene A.F., Burton E.D., Bush R.T., Sullivan L.A., McElnea A.E., Ahern C.R., Smith C.D., Powell B. (2010) Arsenic mobilisation in a seawater inundated acid sulfate soil. Environmental Science and Technology, 44 (6), 1968-1973. (2010 ERA ranking A*)

Keene A.F., Johnston S.G., Bush R.T., Burton E.D., Sullivan L.A. (2010) Reactive trace element enrichment in a highly modified, tidally inundated acid sulfate soil wetland: East Trinity, Australia. Marine Pollution Bulletin, 60 (4), 620-626. (2010 ERA ranking B)

Watling K.M., Burton E.D., Johnston S.G., Bush R.T., Sullivan L.A. (2010). Electrochemical analysis of highly reactive pyrite. ECS Transactions 28, 129-140.

Wong V.N.L., Johnston S.G., Burton E.D., Bush R.T., Sullivan L.A., Slavich P.G. (2010) Seawater causes rapid trace metal mobilisation in coastal lowland acid sulfate soils: implications of sea level rise for water quality. Geoderma, 160, 252-263 (2010 ERA ranking A)

Wong V.N.L., Johnston S.G., Bush R.T., Sullivan L.A., Clay C., Burton E.D., Slavich P.G. (2010) Spatial and temporal changes in estuarine water quality during a post-flood hypoxic event. Estuarine, Coastal and Shelf Science, 87, 73-82. (2010 ERA ranking A)

2009

Burton E.D., Bush R.T., Johnston S.G., Watling K., Hocking R.K., Sullivan L.A., Heber G.K. (2009) Sorption of arsenic(V) and arsenic(III) to schwertmannite.Environmental Science & Technology 43, 9202-9207.

Burton E.D., Bush R.T., Sullivan L.A., Hocking R.K., Mitchell D.R.G., Johnston S.G., Fitzpatrick R.W., Raven M., McClure S., Jang L.Y. (2009) Iron-monosulfide oxidation in natural sediments: Resolving microbially mediated S transformations using XANES, electron microscopy, and selective extractions. Environmental Science & Technology 43, 3128-3134.

Isaacson L.S., Burton E.D., Bush R.T., Mitchell D.R.G., Johnston S.G., Macdonald B.C.T., Sullivan L.A., White I. (2009) Iron(III) accumulations in inland saline waterways, Hunter Valley, Australia: Mineralogy, micromorphology and pore-water geochemistry. Applied Geochemistry 24, 1825-1834.

Johnston S.G., Burton E.D., Bush R.T., Keene A.F., Sullivan L.A., Isaacson L. (2009) Pore water sampling in acid sulfate soils: a new peeper method. Journal of Environmental Quality, 38, 2474-2477.

Johnston S.G., Bush R.T., Sullivan L.A., Burton E.D., Smith D., Martens M.A., McElneaA.E., Ahern C.R., Powell B., Stephens L.P., Wilbraham S.T., van Heel S., (2009). Changes in water quality following tidal inundation of coastal lowland acid sulfate soil landscapes. Estuarine, Coastal and Shelf Science 81, 257-266.

Johnston S.G., Hirst P., Slavich P.G., Bush R.T., Aaso T.(2009) Saturated hydraulic conductivity of sulfuric horizons in coastal floodplain acid sulfate soils: Variability and implications. Geoderma 151, 387-394.

Johnston S.G., Keene A.F., Bush R.T., Burton E.D., Sullivan L.A., Smith D., Martens M.A., McElnea A.E., Wilbraham S.T. (2009). Contemporary pedogenesis of severely degraded tropical acid sulfate soils after introduction of regular tidal inundation. Geoderma 149, 335-346.

2008

Burton E.D., Bush R.T., Sullivan L.A., Johnston S.G., Hocking R.K. (2008). Mobility of arsenic and selected metals during re-flooding of iron- and organic-rich acid-sulfate soil. Chemical Geology 253, 64-73.

Burton E.D., Sullivan L.A., Bush R.T, Johnston S.G., Keene A.F. (2008). A simple and inexpensive chromium-reducible sulfur method for acid-sulfate soils. Applied Geochemistry 23, 2759-2766.

2005

Johnston S.G., Slavich P.G., Hirst P., (2005). Changes in surface water quality after inundation of acid sulfate soils with different vegetation cover. Australian Journal of Soil Research 43, 1-12.

Johnston S.G., Slavich P.G., Hirst P., (2005). The effects of controlled tidal exchange on improving drainage water quality in acid sulfate soil backswamps. Agricultural Water Management 73, 87-111.

Johnston S.G., Slavich P.G., Hirst P., (2005). Opening floodgates in coastal floodplain drains: effects on tidal forcing and lateral transport of solutes in adjacent groundwater. Agricultural Water Management 74, 23-46.

2004

Bush R.T., Sullivan L.A., Fyfe D., Johnston S.G., (2004). Redistribution of monosulfidic black oozes (MBO) by floodwaters in a coastal acid sulfate soil floodplain. Australian Journal of Soil Research 42, 603-607.

Johnston S.G., Slavich P.G., Hirst P. (2004). The acid flux dynamics of two artificial drains in acid sulfate soil backswamps on the Clarence River floodplain, Australia. Australian Journal of Soil Research 42 (5), 623-637.

Johnston S.G., Slavich P.G., Hirst P. (2004). The effects of a weir on reducing acidflux from a drained coastal acid sulfate soil backswamp. Agricultural Water Management 69, 43-67.

2003

Johnston S.G., Slavich P.G., Hirst P. (2003). Alteration of groundwater and sediment geochemistry in a sulfidic backswamp due to Melaleuca quinquenervia encroachment. Australian Journal of Soil Research 14, 1343-1367.

Johnston S.G., Slavich P., Sullivan L.A., Hirst P. (2003). Artificial drainage of floodwaters from sulfidic backswamps: effects on deoxygenation in an Australian estuary. Marine and Freshwater Research 54, 781-795.

Data collections

Keene A.F., Johnston S.G., Bush R.T., Burton E.D., Sullivan L.A. Dundon M., McElnea A.E., Smith C.D., Ahern C.R., Powell B. (2014) Data from: Enrichment and heterogeneity of trace elements in redox-interfacial coastal sediments View data collection here

Conference proceedings

2014

Hirst, P., Bush, R., Slavich, P., Johnston S.G. (2014) Effect of extreme heat on Fe oxides and trace metals in organic rich acid sulfate soils. In: "Proceedings of the 4th National Conference on Acid Sulfate Soils". 20th-21st May 2014, Perth, Australia.

Johnston S.G., Burton, E.D., Aaso, T., Tuckerman, G. (2014) Sulfur, iron and carbon cycling following remediation of coastal acid sulfate soils by freshwater re-flooding. In: "Proceedings of the 4th National Conference on Acid Sulfate Soils". 20th-21st May 2014, Perth, Australia.

Johnston S.G., Burton, E.D., Aaso, T., Tuckerman, G. (2014) Oscillations in surface water quality in freshwater re-flooded coastal acid sulfate soil wetlands. In: "Proceedings of the 4th National Conference on Acid Sulfate Soils". 20th-21st May 2014, Perth, Australia.

Johnston S.G., Burton, E.D., Morgan, B., Joannes-Boyau, R. (2014) Legacy impacts of acid sulfate soil runoff on iron, sulfur, REE and trace element geochemistry in mangrove sediments. In: "Proceedings of the 4th National Conference on Acid Sulfate Soils". 20th-21st May 2014, Perth, Australia.

Johnston S.G., Burton, E.D., Hagan, R. (2014) A revised TAA method for re-flooded acid sulfate soils. In: "Proceedings of the 4th National Conference on Acid Sulfate Soils". 20th-21st May 2014, Perth, Australia.

Karimian, N., Johnston S.G., Burton, E.D. (2014) Kinetics and magnitude of acidity generation during simulated oxidation of re-flooded freshwater acid sulfate soils. In: "Proceedings of the 4th National Conference on Acid Sulfate Soils". 20th-21st May 2014, Perth, Australia.

2013

Burton, E.D., Johnston S.G., Adams, D. (2013) Coupling of arsenic mobility to sulfur biogeochemistry in near-surface environments. In: "Proceedings of the 23rd Annual V.M. Goldschmidt Conference". 25-30th August 2013, Florence, Italy(Geochemical Society, and European Society for Geochemistry).

Johnston S.G., Burton, E.D., Aaso, T., Tuckerman, G. (2013) Remediation of coastal acid sulfate soils by freshwater re-flooding. In: "Proceedings of the 22nd NSW Coastal Conference". 12-15 November, Port Macquarie, NSW.

Johnston S.G. (2013) Iron geochemistry in redox-dynamic coastal wetlands: consequences for trace element cycling in the environment. In: "Proceedings of the 23rd Annual V.M. Goldschmidt Conference". 25-30th August 2013, Florence, Italy (Geochemical Society, and European Society for Geochemistry).

2012

Hirst P., Bush R., Slavich P., Johnston S.G. (2012) Effect of bushfire on soil geochemistry in Fe and organic rich (peat) acid sulfate soil material. In; "3rd National Conference on Acid Sulfate Soils". 6th-7th March 2012, Melbourne, Victoria.

Johnston S. G., Keene A. F., Burton E. D., Bush R. T., Sullivan L. A. (2012) Hydro-geochemical coupling in seawater inundated acid sulfate soils: mobilisation of arsenic and hysteresis in iron and sulfur cycling. In; "3rd National Conference on Acid Sulfate Soils". 6th-7th March 2012, Melbourne, Victoria.

Keene A.F., Johnston S.G., Burton E.D., Bush R.T., Sullivan L.A. (2012) Reductive biomineralisation of pedogenic jarosite in tidally inundated acid sulfate soils. In; "3rd National Conference on Acid Sulfate Soils". 6th-7th March 2012, Melbourne, Victoria.

Sullivan L., Watling K., Claff S., Bush R., Burton E., Johnston S.G., Ahern C., McElnea A. (2012) Assessing acid sulfate soil neutralising capacity: a new approach. In; "3rd National Conference on Acid Sulfate Soils". 6th-7th March 2012, Melbourne, Victoria.

Wong V.N.L., Triantafilis J., Johnston S.G., Nhan T., Sullivan L.A., Bush R.T., Burton, E.D., Slavich P.G., Hirst P. (2012) A new method to rapidly and accurately map acid sulfate soils: exploring the utility of an EM38. In; "3rd National Conference on Acid Sulfate Soils". 6th-7th March 2012, Melbourne, Victoria.

2011

Burton E.D, Johnston S.G., Bush R.T. (2011) The role of microbial sulfidogenesis in shaping iron-sulfur-arsenic interactions within floodplain soils. In: "Proceedings of the 21th Annual V.M. Goldschmidt Conference". 14-19 August 2011, Prague, Czech Republic (Geochemical Society, and European Society for Geochemistry).

Johnston S. G., Keene A. F., Burton E. D., Bush R. T., Sullivan L. A. (2011) Hydrological controls on acid generation and export in floodplain wetlands. In: "Proceedings of the SL & NZFSS Congress 2011". 26th - 30th September 2011, Brisbane Convention and Exhibition Centre, Brisbane, Queensland.

Keene A.F., Johnston S.G., Burton E.D., Bush R.T. (2011) As, Fe and S cycling during reductive biomineralisation of pedogenic jarosite In: "Proceedings of the 21th Annual V.M. Goldschmidt Conference". 14-19 August 2011, Prague, Czech Republic (Geochemical Society, and European Society for Geochemistry).

Wong V.N.L., Johnston S.G., Walsh S., Morris S., Burton E.D, Bush R., Sullivan L., Slavich, P. (2011) Episodic estuarine hypoxic events: integrating the biogeochemistry, hydrology and climate on a subtropical floodplain, eastern Australia. In: "Proceedings of the 21th Annual V.M. Goldschmidt Conference". 14-19 August 2011, Prague, Czech Republic (Geochemical Society, and European Society for Geochemistry).

Wong V.N.L., Walsh S., Johnston S.G., Morris S., Bush R., Sullivan L. (2011) Climate and landscape drivers of estuarine deoxygenation events. In 'Australia/New Zealand Geomorphology Group'. 31st January - 4th February 2011. Oamaru, New Zealand.

2010

Ahern C., Smith D., McElnea A., Bush R., Johnston S., Wilbraham S., Van Heel S., Keene A., Powell B., and Malone B. (2010) A national demonstration site for acid sulfate soil remediation in the Australian tropics - an overview of the East Trinity environmental success story. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Burton E.D., Bush R.T., Johnston S.G., Keene A.F., Sullivan L.A (2010) Sulfur biomineralisation across a spatio-temporal hydrogeochemical gradient in an acid sulfate soil wetland. In: "Proceedings of the 20th Annual V.M. Goldschmidt Conference". 13-18 June 2010, Knoxville, Tennessee (Geochemical Society, and European Society for Geochemistry).

Burton E.D., Bush R.T., Johnston S.G., Sullivan L.A., Keene A.F. (2010) Reductive sulfur biomineralisation in a re-flooded acid-sulfate soil landscape. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Bush R.T., Sullivan L.A., Burton E.D., Johnston S.G., Keene A.F., Wong V., Mosely L. (2010) Climate change impacts on acid sulfate soil landscapes. In: "Proceedings of the 20th Annual V.M. Goldschmidt Conference". 13-18 June 2010, Knoxville, Tennessee (Geochemical Society, and European Society for Geochemistry).

Bush R., Sullivan L., Johnston S., Burton E., Wong V., Keene A. (2010) Climate change: a frontier for acid sulfate soil research. In '19th World Congress in Soil Science: 1st - 6th August.' Brisbane

Hirst P., Slavich P., Johnston S., Walsh S. (2010) Assessment of saturated hydraulic conductivity in coastal floodplain acid sulfate soils In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Johnston S.G., Keene A.F., Bush R.T., Burton E.D., Sullivan L.A. (2010) Mobilisation of arsenic following sea-water inundation of acid sulfate soils. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Johnston S.G., Keene A.F., Bush R.T., Burton E.D., Sullivan L.A. (2010) Remediating coastal acid sulfate soils by tidal inundation: geochemical hysteresis of iron. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Johnston S.G., Keene A.F., Bush R.T., Burton E.D., Sullivan L.A. (2010) Seawater inundation of Fe-rich coastal lowlands - hydrogeochemical coupling and hysterisis at the tidal fringe. In: "Proceedings of the 20th Annual V.M. Goldschmidt Conference". 13-18 June 2010, Knoxville, Tennessee (Geochemical Society, and European Society for Geochemistry).

Johnston S.G., Keene A.F., Bush R.T., Burton E.D., Sullivan L.A. Wong V.N.L. (2010) Mobilisation of groundwater arsenic at the tidal fringe: hydro-geochemical coupling in seawater inundated coastal lowlands. In: "The challenges of sustainable management: National Groundwater Conference 2010" 31 October - 4 November 2010, National Convention Centre, Canberra.

Keene A.F., Johnston S.G., Bush R.T., Sullivan L.A., Burton E.D., (2010) Reductive dissolution of natural jarosite in a tidally inundated acid sulfate soil: geochemical implications. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Keene A.F., Johnston S.G., Bush R.T., Sullivan L.A., Burton E.D., (2010) Sulfidisation processes in a reactive Fe-enriched acid sulfate soil, north-eastern Australia. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Vithana C., Sullivan L., Bush R., Burton E., Johnston S. (2010) Evaluation of existing methods for assessing retained acidity in acid sulfate soil materials. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Watling K.M., McElnea A., Ahern C., Burton E.D., Johnston S.G., Keene A.F., Bush R.T., Sullivan L.A. (2010) Effectiveness of lime particle size in the neutralisation of sulfidic acid sulfate soil materials. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Wong V.N.L., Hirst P., Johnston S.G., Bush R.T., Sullivan L.A., Burton E.D., Slavich P.G. (2010) Impacts of sea level rise on the biogeochemistry of a coastal floodplain in eastern Australia. In: "Proceedings of the 19th World Congress of Soil Science, Brisbane". 1-6 August, Brisbane, Australia.

Wong V.N.L., Johnston S.G., Hirst P., Burton E.D., Bush R.T., Sullivan L.A., Slavich P. (2010) Sea-level rise impacts on coastal water quality: Interactions between porewater, surface- and shallow groundwater geochemistry. In: "The challenges of sustainable management: National Groundwater Conference 2010" 31 October - 4 November 2010, National Convention Centre, Canberra.

Wong V.N.L., Johnston S.G., Bush R.T., Sullivan L.A., Burton E.D., Slavich P.G. (2010) The effects of increasing salinity on exchange processes in coastal lowland acid sulfate soils. In '19th World Congress in Soil Science: 1st - 6th August.' Brisbane

2009

Burton E.D., Johnston S.G., Bush R.T., Sullivan L.A., Keene A.K., Watling K. (2009) Iron-sulfur biomineralisation and arsenic mobility in acid-sulfate wetlands. In: "Proceedings of the 19th Annual V.M. Goldschmidt Conference". 21-26 June 2009, Davos Switzerland (Geochemical Society and European Association for Geochemistry). Pg A179.

Isaacson L.S., Burton E.D, Bush R.T., Johnston S.G, Sullivan L.A.(2009). Biomineralisation of nano Fe(III) phases in inland waterways. "Proceedings of the 19th Annual V.M. Goldschmidt Conference". 21-26 June 2009, Davos Switzerland (Geochemical Society and European Association for Geochemistry). Pg A571.

Johnston S.G., Keene A.F., Bush R.T., Burton E.D., Sullivan L.A. (2009) Remediation of coastal acid sulfate soils by tidal inundation: Effectiveness and geochemical implications. In: "Proceedings of the 18th NSW Coastal Conference". 3-6 November, Ballina, NSW.

Wong V.N.L., Johnston S., Bush R., Sullivan L., Clay C. (2009) Geomorphic controls on post-flood water quality on a coastal floodplain. In "7th International Conference on Geomorphology: 6th - 11th July." Melbourne.

2008

Bush R.T., Burton E.D., Sullivan L.A. and Johnston S.G. (2008). Catalytic action of aqueous ferrous iron and sulfide on the transformation of iron oxides in acid sulfate soils. In: "Proceedings of the Joint Conference of the 6th InternationalAcid Sulfate Soil Conference and the Acid Rock Drainage Symposium". (Eds. C. Lin, S. Huang & Y. Li). 16-20 September 2008 Guangzhou China. (Guangdong Press Group). pp.259-260.

Bush R.T., Johnston S.G. Sullivan L.A., Burton E. D., Ahern C., Powell B., McElnea A. and Smith D. (2008). Impacts of climate change and sea-level rise on acid sulfate soils. In: "Proceedings of the Joint Conference of the 6th International Acid Sulfate Soil Conference and the Acid Rock Drainage Symposium". (Eds. C. Lin, S. Huang & Y. Li). 16-20 September 2008 Guangzhou China. (Guangdong Press Group). pp. 260.

Bush R.T., Johnston S.G., Toppler N., Hurst P., Burton E.D., Sullivan L.A. and Slavich P. (2008). Managing floodplain drains to reduce acid export from acid sulfate soil backswamps. In: "Proceedings of the Joint Conference of the 6th International Acid Sulfate Soil Conference and the Acid Rock Drainage Symposium". (Eds. C. Lin, S. Huang & Y. Li). 16-20 September 2008 Guangzhou China. (Guangdong Press Group). pp. 261.

Johnston S.G., Bush R.T., Sullivan L.A., Burton E.D., Smith D., Martens M.A., McElnea A.E., Ahern C.R., Powell B., Stephens L.P., Wilbraham S.T., van Heel S. (2008). A national demonstration site for innovative acid sulfate soil research, East Trinity. CRC CARE National Conference 2008, Adelaide.

Johnston S.G., Bush R.T., Sullivan L.A., Burton E.D., Smith D., Martens M.A., McElnea A.E., Ahern C.R., Powell B., Stephens L.P., Wilbraham S.T.,van Heel S.(2008). Improvements in water quality following restoring tidal exchange in and acidified, diked and drained estuarine catchment. In: "Proceedings of the 6th International Acid Sulfate Soil Conference"(Eds: C. Lin, S. Huang, Y. Li). Guangdong Press Group, China, pp. 74-78.

Martens M.A., Ahern C.R., Smith D., McElnea A.E., Wilbraham S.T., Stephens L.P., van Heel S., Johnston S.G. (2008) Returning the tide: Overview, concepts and background to the acid sulfate soil remediation at East Trinity, Cairns, Australia. In: "Proceedings of the 6th International Acid Sulfate Soil Conference" (Eds. C. Lin, S. Huang & Y. Li). Guangdong Press Group, China, pp.132-136.

2003

Aaso T., Rogers M., Johnston S. (2003) Remediation of Partridge Creek Acid Sulfate Soil Hot Spot. In "NSW Coastal Conference Proceedings, 4-7 November 2003, Port Panthers Club, Port Macquarie NSW." (Hastings Council: Port Macquarie.) pp. 1-7.

2002

Bush R.T., Sullivan L.A., Johnston S.G., Fyfe D., Claff S., Slavich P.G. (2002) Mobility of monosulfidic black oozes in coastal acid sulfate soil landscapes. In: "Sustainable Management of Acid Sulfate Soils. Fifth International Acid Sulfate Soil Conference, August, 25-30th, 2002, Tweed Heads, NSW." (Eds. B.C.T. Macdonald, A.F. Keene, G.Carlin and L.A. Sullivan), (Acid Sulfate Soil Working Group, International Union of Soil Sciences) pp. 105

Hirst P., Johnston S.G., Slavich P.G. (2002) Lateral salt seepage into shallow coastal aquifers from tidal drains. In: "Sustainable Management of Acid Sulfate Soils. Fifth International Acid Sulfate Soil Conference, August, 25-30th, 2002, Tweed Heads,NSW." (Editors. B.C.T. Macdonald, A.F. Keene, G. Carlin and L.A. Sullivan), (Acid Sulfate Soil Working Group, International Union of Soil Sciences)pp. 143-144

Johnston S.G., Slavich P.G., Hirst P. (2002) Deep flooding of sulfidic backswamps and artificial drainage - links to estuarine deoxygenation and scald formation. In: "Sustainable Management of Acid Sulfate Soils. Fifth International Acid Sulfate Soil Conference, August, 25-30th, 2002, Tweed Heads, NSW." (Editors. B.C.T. Macdonald, A.F. Keene, G. Carlin and L.A. Sullivan), (Acid Sulfate Soil Working Group, International Union of Soil Sciences) pp. 147-148

Johnston S.G., Slavich P.G., Hirst P. (2002) Floodgate and drainage system management, opportunities and limitations - an acid export perspective. In "Floodgate Design and Modification Workshop, Ballina, NSW, 14th August 2002." (Ed. S. Walsh.) (NSW Fisheries: Ballina.) pp. 59-73.

Johnston S.G., Slavich P.G., Hirst P. (2002) Hydrological effects of floodgate management on coastal floodplain agriculture. In: 'Australian Soil Science Society, NSW Branch, North Coast Soils Tour 21-22 November 2002.' (Wollongbar) pp. 6-17.

Johnston S.G., Slavich P.G., Hirst P. (2002) Melaleuca quinquenervia encroachment in sulfidic backswamps - links to increasing groundwater acidity. In: "Sustainable Management of Acid Sulfate Soils. Fifth International Acid Sulfate Soil Conference, August, 25-30th, 2002, Tweed Heads, NSW."(Editors. B.C.T. Macdonald, A.F. Keene, G. Carlin and L.A. Sullivan), (Acid Sulfate Soil Working Group, International Union of Soil Sciences) pp. 151-152

Johnston S.G., Slavich P.G., Hirst P. (2002) Sources of salinity in low elevation coastal floodplain soil landscapes and effects on cane yield. In: "Sustainable Management of Acid Sulfate Soils. Fifth International Acid Sulfate Soil Conference, August, 25-30th, 2002, Tweed Heads, NSW." (Editors. B.C.T. Macdonald, A.F. Keene, G. Carlin and L.A. Sullivan), (Acid Sulfate Soil Working Group, International Union of Soil Sciences) pp. 148-149

Johnston S.G., Slavich P.G., Hirst P. (2002) The acid flux dynamics of two artificial drains in sulfidic backswamps on the Clarence River floodplain, Australia - Management implications. In: "Sustainable Management of Acid Sulfate Soils. FifthInternational Acid Sulfate Soil Conference, August, 25-30th, 2002, Tweed Heads, NSW." (Eds: B.C.T. Macdonald, A.F. Keene, G. Carlin and L.A. Sullivan), (Acid Sulfate Soil Working Group, International Union of Soil Sciences) pp. 79-80

Books

Johnston S., Kroon F., Slavich P., Cibilic A. & Bruce A. (2003) Restoring the balance: Guidelines for managing floodgates and drainage systems on coastal floodplains. NSW Agriculture: Wollongbar, Australia, pp 1-47. ISBN 0 7347 1518 8.

Other Publications

2007

Johnston S.G. (2007) Reviewing indicators of sustainable agriculture: Final Report. NSW Department of Primary Industries, Wollongbar, pp 1-63.

2005

Johnston S.G. (2005) 'The hydrology, biogeochemistry and management of drained coastal acid sulfate soil backswamps in the lower Clarence River floodplain'. Ph.D. Thesis. pp. 345.

2004

Johnston S.G., Slavich P.G. and Hirst P. (2004) The hydrological effects of floodgate management on coastal floodplain agriculture, DAN13: Final report to Land and Water Australia. NSW Agriculture, Wollongbar.

Johnston S. (2004) Managing floodgates to improve drain water quality Floodgate and drain management on coastal floodplains leaflet 1. (NSW Agriculture: Wollongbar)

Johnston S. (2004) Managing drains to reduce acid export. Floodgate and drain management on coastal floodplains leaflet 2. (NSW Agriculture: Wollongbar)

Johnston S., Bruce A., Kroon F. (2004) Managing drains and tidal creeks for fish passage. Floodgate and drain management on coastal floodplains leaflet 3. (NSW Agriculture: Wollongbar)

Johnston S. (2004) Managing salt water when opening floodgates Floodgate and drain management on coastal floodplains leaflet 4. (NSW Agriculture: Wollongbar)

Johnston S. (2004) How leaky are your soils? Groundwater flow in acid sulfate soils. Floodgate and drain management on coastal floodplains leaflet 5. (NSW Agriculture: Wollongbar)

Johnston S. (2004) Floodgates and retention structures - choosing the right design. Floodgate and drain management on coastal floodplains leaflet 6. (NSW Agriculture: Wollongbar)

Johnston S., Slavich P., Hirst P. (2004) Shark creek acid sulfate soil study site - The effects of the weir at reducing acid export during 2003. (NSW Agriculture, Grafton). pp. 1-10.

2003

Johnston S.G., MacDonald B. (2003) Soil permeability can effect acid export and salt seepage. Australian Sugarcane 7 (2), 21-22.

Johnston S.G., Slavich P.G. (2003) Hydraulic conductivity - a simple field test for shallow coastal acid sulfate soils. (NSW Agriculture: Wollongbar, Australia.) pp. 1-9.

Johnston S.G., Slavich P., Hirst P. (2003c) Hydraulic conductivity in the sulfuric horizons at Partridge Creek acid sulfate soil hotspot. Report DAN13/1. (NSW Agriculture, Wollongbar, Australia). pp. 1-9.

1995

Johnston S.G. (1995) The effects of acid sulphate soils on water quality in the Maria River Estuary, NSW. Report to Hastings Council. Hastings Council, Port Macquarie. pp. 201.