SQI Application Guide

Welcome to the Soil Quality Index Calculator

This application implements a comprehensive workflow for calculating and mapping soil quality indices using Principal Component Analysis (PCA) and geostatistical methods.

Workflow Steps:

  1. Input Data: Upload your soil data (CSV/XLS) with X, Y coordinates and soil properties
  2. Exploratory Analysis: Examine correlations and remove highly correlated variables (>0.98)
  3. PCA Analysis: Perform Principal Component Analysis to determine variable weights
  4. SQI Calculation: Define normalization parameters and calculate the Soil Quality Index
  5. Spatial Assessment: Apply geostatistical interpolation (Kriging or IDW)
  6. Results: Visualize spatial distribution and download maps

Data Requirements:

  • CSV or Excel file with soil property data
  • Mandatory columns: X, Y (coordinates)
  • Soil properties: Any numerical variables (pH, organic matter, texture, nutrients, physical properties, etc.)
  • The application will automatically detect all numerical variables for analysis
  • Study area boundary (optional): GeoJSON or GeoPackage format

Normalization Types:

  • More is Better: Higher values indicate better soil quality (e.g., organic matter, nutrients)
  • Less is Better: Lower values indicate better soil quality (e.g., bulk density)
  • Optimal Range: Values within a specific range are considered optimal (e.g., pH, texture)

Recommended Optimal Ranges:

  • pH: 6.5 - 7.5 (optimal for most crops)
  • Clay: 10% - 25% (balanced texture)
  • Silt: 30% - 50% (good water retention)
  • Sand: 40% - 60% (adequate drainage)
  • EC: 2.0 - 15.0 dS/m (moderate salinity range)

Data Upload

Coordinate System


Data Preview

Data Summary


                  

Variable Selection

Select Variables for Analysis:


Correlation Matrix

Variable Statistics

Removed Variables


                  

PCA Controls



PCA Parameters:

Scree Plot

Variable Contributions

PCA Weights

PCA Biplot

Normalization Settings

Configure normalization for each variable:

Select the normalization type and define optimal ranges where applicable.

SQI Calculation



SQI Statistics:


                  

SQI Distribution

SQI by Sample Points

Interpolation Settings

Kriging Parameters:
IDW Parameters:

Variogram

IDW method selected - no variogram needed

Interpolation Summary


                  

Spatial Distribution Map

SQI Classification

SQI Quality Classes:

Final Results Summary