Use of fluoride-containing water for the irrigation of soil-plant systems.
Many groundwaters used for irrigation contain elevated concentrations of F, but much remains unknown regarding how this F behaves within soils and plants. The present study investigated the adsorption and desorption of F from several soils in short- to medium-term irrigation systems and related foliar F concentrations in three forage plant species to the maximum tolerable level (MTL) in the diets of grazing animals (being 1.8 μmol/g for young cattle, for example). Although adsorption isotherms could be successfully used to predict the behavior (adsorption and desorption) of F within the soil, this was not related to the subsequent accumulation of F in plant foliage. In addition, the extent to which F accumulated in the foliage depended on the plant species. Regardless, F generally did not accumulate in plant foliage to levels exceeding the MTL when used at rates equivalent to irrigation for 25 years. In addition to uptake by roots, F may accumulate in foliar tissues directly due to retention from overhead irrigation. The data presented here regarding the behavior of F in soils and plants will assist in the rigorous regulation of F-containing irrigation water to ensure maximum plant growth while simultaneously minimizing potential harm.
†The University of Queensland, School of Agriculture and Food Sciences, St Lucia, Queensland 4072, Australia.
Lisa M
LM
Scholz
†The University of Queensland, School of Agriculture and Food Sciences, St Lucia, Queensland 4072, Australia.
Peter M
PM
Kopittke
†The University of Queensland, School of Agriculture and Food Sciences, St Lucia, Queensland 4072, Australia.
Neal W
NW
Menzies
‡Santos, Queensland Business Unit Environment, Brisbane, Queensland 4000, Australia.
Scott A
SA
Dalzell
‡Santos, Queensland Business Unit Environment, Brisbane, Queensland 4000, Australia.
David C
DC
Macfarlane
†The University of Queensland, School of Agriculture and Food Sciences, St Lucia, Queensland 4072, Australia.
J Bernhard
JB
Wehr
D057914:Agricultural Irrigation; D005459:Fluorides / Q000032:analysis* / Q000378:metabolism; D006109:Poaceae / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D005459:Fluorides
Rhodes grass; adsorption and desorption; fluoride toxicity; fluoride uptake; leucaena; lucerne