Geographical Distribution of Fluorides in Forage Using a Bioindicator

Abstract

AbstractFluoride levels in leaves of black locust (Robinia pseudoacacia L.) collected in late summer were used to predict geographical distributions of average seasonal pasture forage and hay fluoride levels near a source of airborne fluorides.Simple linear regression models with various logarithmic transformations were tested. Greatest proportions of the total variation were explained by the linear regression model for second‐cutting hay (81%) and by a logarithmic transformation of the dependent variable for average pasture forage (63%). None of the models tested were found adequate for predicting fluoride levels in first‐cutting hay. Isopleth maps based on predicted fluoride values compared favorably with those derived from direct measurements.The use of black locust foliage as a quantitative bioindicator of geographical forage fluoride levels can provide considerable savings in material and personnel in long term fluoride surveys.