SUPERVISED MACHINE LEARNING BASED DYNAMIC ESTIMATION OF BULK SOIL MOISTURE USING COSMIC RAY SENSOR

Ritaban Dutta, Claire D’Este

Abstract: In this paper artificial neural network based sensor informatics architecture has been investigated; including proposed continuous daily estimation of area wise surface soil moisture using cosmic ray sensor’s neutron count time series. Study was conducted based on cosmic ray data available from two Australian locations. The main focus of this study was to develop a data driven approach to convert neutron counts into area wise ground surface soil moisture estimates. Independent surface soil moisture data from the Australian Water Availability Project (AWAP) was used as ground truth. A comparative study using five different types of neural networks, namely, Feed Forward Back Propagation (FFBPN), Multi-Layer Perceptron (MLPN), Radial Basis Function (RBFN), Elman (EN), and Probabilistic networks (PNN) was conducted to evaluate the overall soil moisture estimation accuracy. Best performance from the Elman network outperformed all other neural networks with 94% accuracy with 92% sensitivity and 97% specificity based on Tullochgorum data. Overall high accuracy proved the effectiveness of the Elman neural network to estimate surface soil moisture continuously using cosmic ray sensors.

Keywords: Artificial Neural Network, Surface Soil Moisture, Cosmic Ray Sensors, Neutron Counts.

DOI: https://doi.org/10.15623/ijret.2013.0208040