Effects of pH and ionic strength on elemental sulphur oxidation in soil
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Elemental S oxidation in soil is a microbially mediated process and is hypothesised to be influenced by changes to soil chemical properties such as acidity and ionic strength, which may arise from co-granulation with macronutrients or elemental S oxidation itself. Soil incubation was conducted with a sandy soil from South Australia to assess the effect of acidification and increased ionic strength on bacterial abundance and community composition and on elemental S oxidation during a 14-week incubation at 25 °C and 70% field capacity. Prior to incubation, the soil was treated with HNO3 to bring the pH to 6.7–4.4 or with KH2PO4 to increase the ionic strength by 0–0.7 M. Elemental S was applied at 200 mg kg−1 air-dried soil. Acidification or increased ionic strength had no or little effect on elemental S oxidation but decreased the abundances of 16S ribosomal deoxyribonucleic acid (rRNA) and soxB genes and changed the bacterial community composition. A second experiment with two other soils also showed that acidification did not, or only slightly, decreased elemental S oxidation, even though acidification strongly reduced 16S rRNA and soxB gene abundances in one of the soils. This study suggests that shifts in bacterial population brought about by temporary changes in pH and ionic strength, as may occur around fertiliser granules, have no or little effect on elemental S oxidation, indicating that the S-oxidising bacterial community in these agricultural soils contains functionally redundant taxa, which responded to changing conditions.
KeywordsElemental S oxidation pH Ionic strength Bacterial population
The authors would like to acknowledge the China Scholarship Council for providing the scholarship and Mosaic Company for support. We would also like to thank Marcus Hicks for his assistance with TRFLP analysis and Bogumila Tomczak, Colin Rivers and Ashleigh Broadbent for their assistances with chemical analysis.
- Lehman RM, Acosta-Martinez V, Buyer JS, Cambardella CA, Collins HP, Ducey TF, Halvorson JJ, Jin VL, Johnson JMF, Kremer RJ, Lundgren JG, Manter DK, Maul JE, Smith JL, Stott DE (2015) Soil biology for resilient, healthy soil. J Soil Water Conserv 70:12A–18A. doi: 10.2489/jswc.70.1.12A CrossRefGoogle Scholar
- Marschner P, Kandeler E, Marschner B (2003) Structure and function of the soil microbial community in a long-term fertilizer experiment. Soil Biol Biochem 35:453–461. doi: 10.1016/S0038-0717(02)00297-3
- Ollivier J, Wanat N, Austruy A, Hitmi A, Joussein E, Welzl G, Munch JC, Schloter M (2012) Abundance and diversity of ammonia-oxidizing prokaryotes in the root–rhizosphere complex of Miscanthus giganteus grown in heavy metal-contaminated soils. Microb Ecol 64:1038–1046. doi: 10.1007/s00248-012-0078-y CrossRefPubMedGoogle Scholar
- Petersen DG, Blazewicz SJ, Firestone M, Herman DJ, Turetsky M, Waldrop M (2012) Abundance of microbial genes associated with nitrogen cycling as indices of biogeochemical process rates across a vegetation gradient in Alaska. Environ Microbiol 14:993–1008. doi: 10.1111/j.1462-2920.2011.02679.x CrossRefPubMedGoogle Scholar
- Prevost-Boure NC, Christen R, Dequiedt S, Mougel C, Lelievre M, Jolivet C, Shahbazkia HR, Guillou L, Arrouays D, Ranjard L (2011) Validation and application of a PCR primer set to quantify fungal communities in the soil environment by real-time quantitative PCR. PLoS One 6:1–13Google Scholar
- Rothbaum H, Groom P (1961) Fire hazards in the use of fertilisers containing elemental sulphur. New Zealand J Sci 4:476–488Google Scholar
- Sample EC, Soper RJ, Racz GJ (1980) Reactions of phosphate fertilizers in soils. In: Khasawneh FE, Sample EC, Kamprath EJ (eds) The role of phosphorus in agriculture. American Society of Agronomy, Crop Science Society of America Soil Science Society of America, Madison, pp. 263–310Google Scholar
- Suzuki I, Lee D, Mackay B, Harahuc L, Oh JK (1999) Effect of various ions, pH, and osmotic pressure on oxidation of elemental sulfur by Thiobacillus thiooxidans. Appl Environ Microb 65:5163–5168Google Scholar
- Tourna M, Maclean P, Condron L, O’Callaghan M, Wakelin SA (2014) Links between sulphur oxidation and sulphur-oxidising bacteria abundance and diversity in soil microcosms based on soxB functional gene analysis. FEMS Microbiol Ecol 88:538–549. doi: 10.1111/1574-6941.12323 CrossRefPubMedGoogle Scholar
- Wertz S, Degrange V, Prosser JI, Poly F, Commeaux C, Guillaumaud N, Le Roux X (2007) Decline of soil microbial diversity does not influence the resistance and resilience of key soil microbial functional groups following a model disturbance. Environ Microbiol 9:2211–2219. doi: 10.1111/j.1462-2920.2007.01335.x CrossRefPubMedGoogle Scholar
- Zhao C, Gupta VVSR, Degryse F, McLaughlin MJ (2016b). Abundance and diversity of S-oxidising bacteria and their role in elemental sulphur oxidation in Australian cropping soils. Biol Fertil Soils. doi: 10.1007/s00374-016-1162-0