Multivariate model for predicting crop fluorine content based on soil physicochemical properties and fluorine...

Area of Science:

• Environmental Science
• Agricultural Chemistry
• Geochemistry

Background:

• Fluoride (F) is an essential trace element with significant ecological risks when its biogeochemical cycle is disrupted.
• Assessing crop fluoride bioavailability using total soil F content has limitations.
• Soil-crop systems are vulnerable to fluoride contamination, impacting agricultural sustainability.

Purpose of the Study:

• To investigate fluoride speciation and bioavailability in agricultural soils and wheat.
• To evaluate the limitations of total soil fluoride in predicting crop fluoride accumulation.
• To develop a predictive model for wheat fluoride content based on soil properties.

Main Methods:

• Systematic investigation of 30 paired agricultural soil-wheat samples.
• Sequential extraction to determine fluoride speciation in soils.
• Multivariate analysis to identify factors controlling fluoride accumulation in wheat.

Main Results:

• Residual fluoride was the dominant speciation in soils (79.5-99.04%), limiting environmental mobility.
• Surface soils showed elevated total fluoride (mean 753.3 mg kg⁻¹), but wheat grains remained at safe levels (mean 1.2 mg kg⁻¹).
• A robust multivariate model (R² = 0.72) integrating water-soluble F, CaO, Mn, Al_ox-Fe_ox, P, and pH effectively predicted wheat fluoride accumulation.

Conclusions:

• Total soil fluoride content is not a reliable indicator of fluoride bioavailability in wheat.
• Water-soluble fluoride, along with soil properties like CaO, Mn, Al_ox-Fe_ox, P, and pH, are key predictors of wheat fluoride accumulation.
• Findings support scientific strategies for green agriculture in fluoride-affected regions.