Predicting Soluble Nickel in Soils Using Soil Properties and Total Nickel

Area of Science:

• Environmental Chemistry
• Soil Science
• Geochemistry

Background:

• Soil soluble nickel (Ni) concentration is crucial for assessing Ni toxicity.
• Understanding the factors influencing soluble Ni is vital for environmental risk assessment.

Purpose of the Study:

• To investigate the relationships between soil properties and soluble Ni concentrations.
• To develop predictive models for soil soluble Ni using soil characteristics.

Main Methods:

• Multiple regression analysis was used to identify key soil parameters.
• Soils were categorized by pH (<7, 7-8, >8) for refined predictions.
• Mechanistic speciation models (WHAM VI, Visual MINTEQ3.0) were applied.

Main Results:

• Soil pH and total Ni concentration were the most significant predictors of soluble Ni.
• Categorizing soils by pH enhanced prediction accuracy (Radj2 values up to 0.94).
• Amorphous Fe/Al oxides and clay content also influenced soluble Ni concentrations.

Conclusions:

• Soil properties, particularly pH and total Ni, are effective in predicting soluble Ni concentrations.
• Mechanistic speciation models show applicability for estimating soil soluble Ni, with varying performance across pH ranges.