Mapping the Spatial Variability of Soil Acidity in Zambia
Abstract
:1. Introduction
2. Results and Discussion
2.1. Summary Statistics
2.2. Kriging Interpolated Surface for Soil pH
Statistic | Measured Soil pH | Predicted Soil pH |
---|---|---|
Mean | 4.86 | 4.86 |
Minimum | 4.02 | 4.33 |
Maximum | 5.56 | 5.28 |
Median | 4.88 | 4.88 |
Standard deviation | 0.34 | 0.18 |
1st Quartile | 4.66 | 4.72 |
3rd Quartile | 5.08 | 4.98 |
Skewness | −0.36 | 0.25 |
Kurtosis | 3.11 | 2.89 |
2.3. Spatial Autocorrelation for pH and Model Validation
Fitted Variogram Parameters | |||||||
---|---|---|---|---|---|---|---|
Nugget | Sill | Range (m) | Nugget/Sill Ratio | ||||
0.08 | 0.14 | 1379 | 0.57 | ||||
Prediction Errors for OK Model Implemented to Predict Soil pH | |||||||
Mean | Mean Standardized | RMSE | Average Standard Error | RMSE Standardized | |||
−0.004 | −0.008 | 0.36 | 0.39 | 0.93 |
2.4. Model Validation
3. Experimental Section
3.1. Study Area
3.2. Soil Sampling and Laboratory Analysis
3.3. Data Pre-Processing and Analysis
3.4. Geostatistical Analysis
3.5. Validation of Spatial Prediction of Soil pH
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
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Chabala, L.M.; Mulolwa, A.; Lungu, O. Mapping the Spatial Variability of Soil Acidity in Zambia. Agronomy 2014, 4, 452-461. https://doi.org/10.3390/agronomy4040452
Chabala LM, Mulolwa A, Lungu O. Mapping the Spatial Variability of Soil Acidity in Zambia. Agronomy. 2014; 4(4):452-461. https://doi.org/10.3390/agronomy4040452
Chicago/Turabian StyleChabala, Lydia M., Augustine Mulolwa, and Obed Lungu. 2014. "Mapping the Spatial Variability of Soil Acidity in Zambia" Agronomy 4, no. 4: 452-461. https://doi.org/10.3390/agronomy4040452