title: Interactive effects of soil acidity and fluoride on soil solution aluminium chemistry and barley (Hordeum vulgare L.) root growth.
abstract: A greenhouse study was conducted to determine if concentrations of fluoride (F), which would be added to acid soils via P fertilisers, were detrimental to barley root growth. Increasing rates of F additions to soil significantly increased the soil solution concentrations of aluminium (Al) and F irrespective of the initial adjusted soil pH, which ranged from 4.25 to 5.48. High rates of F addition severely restricted root growth; the effect was more pronounced in the strongly acidic soil. Speciation calculations demonstrated that increasing rates of F additions substantially increased the concentrations of Al-F complexes in the soil. Stepwise regression analysis showed that it was the combination of the activities of AlF2(1+) and AlF(2+) complexes that primarily controlled barley root growth. The results suggested that continuous input of F to soils, and increased soil acidification, may become an F risk issue in the future.
authors.affiliation: Soil and Earth Sciences, Institute of Natural Resources, Massey University, Palmerston North, New Zealand. manoharan.veeragathipillai@uts.edu.au
authors.forename: V
authors.initials: V
authors.lastname: Manoharan
authors.forename: P
authors.initials: P
authors.lastname: Loganathan
authors.forename: R W
authors.initials: RW
authors.lastname: Tillman
authors.forename: R L
authors.initials: RL
authors.lastname: Parfitt
mesh_terms: D000535:Aluminum / Q000032:analysis* / Q000633:toxicity; D017607:Aluminum Compounds / Q000032:analysis; D002118:Calcium / Q000172:deficiency; D005308:Fertilizers / Q000633:toxicity*; D005459:Fluorides / Q000032:analysis / Q000494:pharmacology* / Q000633:toxicity; D001467:Hordeum / Q000187:drug effects / Q000254:growth & development*; D006863:Hydrogen-Ion Concentration; D010758:Phosphorus / Q000633:toxicity; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis / Q000494:pharmacology* / Q000633:toxicity
chemical_list: D017607:Aluminum Compounds; D005308:Fertilizers; D012987:Soil; D012989:Soil Pollutants; D010758:Phosphorus; D000535:Aluminum; D005459:Fluorides; D002118:Calcium