🤖 AI Summary
This study addresses the scarcity of labeled data in early crop stress detection by proposing STS-Net, the first self-supervised spatiotemporal network tailored for this task. Built upon a 3D convolutional autoencoder, the method leverages high-resolution PlanetScope time-series imagery along with four vegetation indices—NDVI, GNDVI, RECI, and NDRE—to learn spatiotemporal stress patterns without requiring extensive annotations. Evaluated on real-world sugarcane fields, STS-Net achieves detection accuracies of 97.98%, 85.08%, and 83.47% for water stress, nitrogen stress, and combined stress, respectively, demonstrating both high classification accuracy and strong generalization capability.
📝 Abstract
Early and accurate detection of crop stress is essential to improve agricultural productivity and ensure global food security. However, collecting a large labeled crop stress dataset is a challenging task. To address this challenge, we introduce a novel spatial-temporal stress network (STS-NET), built on a self-supervised 3D-convolutional autoencoder (3D-CAE), designed to utilize Satellite Image Time Series (SITS) data for crop stress detection. STS-NET exploits four vegetation indices: Normalized Difference Vegetation Index (NDVI), Normalized Difference Vegetation Index (GNDVI), Red-Edge Chlorophyll Index (RECI) and Normalized Difference Red-Edge Index (NDRE) obtained from high resolution Planetscope imagery to capture spatiotemporal stress patterns. The model is trained on our BSPT (Barnala Spatial-Temporal) dataset and evaluated on a real-world sugarcane dataset collected over a year from a 2.5-acre test plot located in Lakhimpur-Kheri (LK) district in Uttar Pradesh in India. STS-NET achieved a precision of 97. 98\% for water stress, 85.08\% for nitrogen stress, and 83.47\% for combined stress. The results demonstrate the potential of STS-NET in effectively detecting stress in sugarcane crops with minimal reliance on labeled data. Furthermore, STS-NET can serve as a robust feature extractor for simpler models.