Enhanced Prediction of Soil Carbon via Encoder-Decoder Neural Networks for a Boreal Study Area in Northern Ontario
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Region
2.2. Soil Data
2.3. Environmental Covariates
2.4. Modeling
2.4.1. Normalization
2.4.2. Encoder-Decoder Neural Networks
2.4.3. Other Models
2.4.4. Model Evaluation
2.5. Uncertainty Quantification
3. Results
3.1. Modeling Accuracies
3.2. Prediction Maps
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Predictor | Source | Soil Formation Factor |
---|---|---|
Digital elevation model (DEM) * | LiDAR | Relief |
Canopy height model (CHM) | LiDAR | Vegetation |
Gap fraction | LiDAR | Vegetation |
Aspect | DEM (LiDAR) | Relief |
Convergence index | DEM (LiDAR) | Relief |
Mid-slope position * | DEM (LiDAR) | Relief |
Multi-resolution ridge top flatness (MRRTF) | DEM (LiDAR) | Relief |
Multi-resolution valley bottom flatness (MRVBF) | DEM (LiDAR) | Relief |
SAGA topographic wetness index (SAGA TWI) | DEM (LiDAR) | Relief |
Slope * | DEM (LiDAR) | Relief |
Slope height * | DEM (LiDAR) | Relief |
Slope length | DEM (LiDAR) | Relief |
Stream power index | DEM (LiDAR) | Relief |
Terrain ruggedness index (TRI) | DEM (LiDAR) | Relief |
Topographic wetness index (TWI) | DEM (LiDAR) | Relief |
Total curvature | DEM (LiDAR) | Relief |
Valley depth | DEM (LiDAR) | Relief |
Visible sky | DEM (LiDAR) | Relief |
B1 summer 2017 | SR | Vegetation |
B2 summer 2017 | SR | Vegetation |
B3 summer 2017 | SR | Vegetation |
B4 summer 2017 | SR | Vegetation |
B5 summer 2017 | SR | Vegetation |
B6 summer 2017 | SR | Vegetation |
B7 summer 2017 | SR | Vegetation |
B10 summer 2017 | SR | Vegetation |
Modified normalized difference water index (MNDWI) summer 2017 | SR | Relief (water) |
Normalized difference vegetation index (NDVI) summer 2017 | SR | Vegetation |
Change magnitude B3 B4 B5 summer 1984–2005 * | SR | Time |
SAR C VH May 2017 | SAR | Relief (water) |
SAR C VV May 2017 * | SAR | Relief (water) |
Gravity anomaly 2016 | Aeromagnetic | Parent material |
Magnetic residual November 2018 | Aeromagnetic | Parent material |
NFI black spruce 2011 * | k-NN model | Vegetation |
ED-DNN | ED-CNN | |||||
---|---|---|---|---|---|---|
Layer | Output Shape | # Parameters | Layer | Output Shape | # Parameters | |
Encoder: | Encoder: | |||||
Input layer | 34 | 0 | Input layer | (1, 34) | 0 | |
Dense | 32 | 1120 | Convolution 1-D | (1, 16) | 560 | |
Dense | 16 | 528 | Max pooling 1-D | (1, 16) | 0 | |
Dense | 8 | 136 | Convolution 1-D | (1, 32) | 544 | |
Decoder: | Flatten | 32 | 0 | |||
Input layer | 8 | 0 | Dense | 8 | 264 | |
Dense | 32 | 288 | Decoder: | |||
Dense | 16 | 528 | Input layer | 8 | 0 | |
Dense | 1 | 17 | Dense | 64 | 576 | |
Reshape | (1, 64) | 0 | ||||
Total parameters: | 2617 | Convolution 1-D | (1, 32) | 2080 | ||
Upsampling 1-D | (2, 32) | 0 | ||||
Convolution 1-D | (2, 16) | 528 | ||||
Flatten | 32 | 0 | ||||
Dense | 16 | 528 | ||||
Dense | 1 | 17 | ||||
Total parameters: | 5097 |
Model | R2 | RMSE | MAE | |
---|---|---|---|---|
[%] | [%] | |||
Structural equation model | SEM | 0.21 | 10.18 | 7.63 |
Random forest | RF | 0.22 | 10.09 | 7.83 |
Dense neural network | DNN | 0.18 | 10.38 | 7.35 |
Convolutional neural network 1-D | CNN | 0.37 | 9.07 | 6.05 |
Encoder-decoder DNN | ED-DNN | 0.54 | 7.78 | 5.40 |
Encoder-decoder CNN 1-D | ED-CNN | 0.59 | 7.30 | 5.38 |
Ensemble * | AVG | 0.50 | 8.06 | 6.11 |
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Pittman, R.; Hu, B. Enhanced Prediction of Soil Carbon via Encoder-Decoder Neural Networks for a Boreal Study Area in Northern Ontario. Sensors 2025, 25, 2583. https://doi.org/10.3390/s25082583
Pittman R, Hu B. Enhanced Prediction of Soil Carbon via Encoder-Decoder Neural Networks for a Boreal Study Area in Northern Ontario. Sensors. 2025; 25(8):2583. https://doi.org/10.3390/s25082583
Chicago/Turabian StylePittman, Rory, and Baoxin Hu. 2025. "Enhanced Prediction of Soil Carbon via Encoder-Decoder Neural Networks for a Boreal Study Area in Northern Ontario" Sensors 25, no. 8: 2583. https://doi.org/10.3390/s25082583
APA StylePittman, R., & Hu, B. (2025). Enhanced Prediction of Soil Carbon via Encoder-Decoder Neural Networks for a Boreal Study Area in Northern Ontario. Sensors, 25(8), 2583. https://doi.org/10.3390/s25082583