West Africa Field Spectrometer

The Dahra Field Spectrometer System (DAFIS) in Senegal is a key automated system for monitoring semi-arid savanna ecosystems using spectral measurements from 350–1800 nm.Overview of DAFISThe Dahra Field Spectrometer System (DAFIS) is located in Senegal, West Africa, and was established to monitor the spectro-directional reflectance properties of semi-arid savanna vegetation . It operates automatically, collecting data daily from sunrise to sunset, covering the visible (VIS), near-infrared (NIR), and shortwave-infrared (SWIR) spectral ranges (350–1800 nm). The system is designed to study surface anisotropy and phenological changes in vegetation, providing continuous time series for ecosystem monitoring.Key CapabilitiesSpectral Measurement: DAFIS captures reflectance data across VIS, NIR, and SWIR bands, enabling detailed analysis of vegetation and soil properties .Anisotropy Analysis: The system measures directional reflectance, revealing how reflectance varies with solar angle and observation direction, which is critical for interpreting satellite data .Vegetation Indices: Data from DAFIS can be used to calculate indices like NDVI and SIWSI, which are sensitive to canopy structure and view angle, aiding in vegetation health assessment .Remote Sensing Validation: The system provides ground-truth data for validating satellite sensors such as MODIS, SPOT, and SEVIRI .Applications in West AfricaEcosystem Monitoring: DAFIS helps track seasonal changes in semi-arid savanna vegetation, including phenology and stress responses .Soil Property Assessment: Field spectroscopy, including mid-infrared measurements, supports rapid evaluation of soil fertility, organic matter, and nutrient content, which is crucial for sustainable agriculture in the West African yam belt .Forage Quality Estimation: Spectral data can be correlated with forage biomass and metabolizable energy, supporting adaptive livestock management in tropical savannas .Research and Algorithm Development: Continuous spectral data enable the development of new Earth Observation indices and algorithms for vegetation monitoring and stress detection .SignificanceThe DAFIS system represents a unique automated field spectrometer in West Africa, providing high-resolution, continuous spectral data that bridge the gap between ground measurements and satellite observations. Its applications span agriculture, ecosystem monitoring, and remote sensing validation, making it a critical tool for environmental research in the region .