KHmer Earth OBServation (KHEOBS) Laboratory
In recent years, satellite images from Synthetic Aperture Radar (SAR) (Sentinel-1, TerraSAR X, CosmoskyMed, RADARSAT-2, ALOS 2) as well as optical sensors (Sentinel 2, Landsat, Pléiades, SPOT 6/7) have become more accessible and frequently available at no cost. This has opened up new opportunities for monitoring, particularly the environments and water bodies. Nevertheless, these data remain underutilized in the context of environmental monitoring and general use in Cambodia. The establishment of the KHmer Earth OBServation (KHEOBS) Laboratory at the Institute of Technology of Cambodia (ITC) is intended to facilitate the utilization of satellite imagery (Sentinel-1 and Sentinel-2) and aerial images. The accessibility of data in Cambodia, and more broadly, is advantageous in numerous domains, including agriculture, land management and urbanization, climate change, biodiversity loss, pollution, and even health monitoring.
Since 2022, two research projects on human health (EASIMES funded by Global Fund, and AfriCAM, funded by AFD) have provided financial support to the KHEOBS Laboratory for the acquisition of a high-performance server with 120 terabytes (TB) of storage, thereby enhancing the data storage and computing capabilities at ITC. The installation of Sen2Chain and Sen2Extract processing chains, developed by IRD UMR Espace-Dev, is designed to automatically generate time series of spatial indicators of the dynamics of water and vegetation from Sentinel-2 satellite imagery every five days (https://sen2extract.kheobs.org/). The iota2 installation is intended to automate the annual land cover mapping of the Tonle Sap Lake. The mapping material will be created for straightforward use by ITC and its partners.
The KHEOBS Laboratory has also worked closely with IGN (Institut national de l’information géographique et forestière) and IGNFI in France to digitize the whole archive of historical aerial images taken in 1952-1954 in Cambodia. From these images, the team produced an exceptional orthophotograph covering most of Cambodia. It also developed a web platform, named GeoCambodia.org to allow these images to be viewed and compared with current views.
Furthermore, the KHEOBS Laboratory is equipped with the capability to observe the water bodies (permanent or regular flooding) as well as soil moisture and land cover from Sentinel-2 satellite images on a five-day cycle, using deep learning and/or machine learning techniques. The KHEOBS Laboratory offers training in the fundamental principles and techniques of analyzing SAR and optical satellite images for the investigation of river-lake hydrology and land use and land cover changes.
With the support of French institutions and infrastructure, such as the IRD UMR Espace-Dev, the KHEOBS Laboratory facilitates the collaboration of scientists and students from Cambodian universities and research institutions through training workshops.
The vision of the KHEOBS Laboratory is to facilitate the development of networks, including: 1) facilitating access to high-quality satellite imagery in conjunction with the French DINAMIS Facility and Theia GeoDev network (https://theia-land.art-geodev.fr/) ; 2) creating interactions for training and development with SEAS-OI and SEAS-Guyane satellite imagery stations connected to the IRD UMR Espace-Dev; 3) promoting interactions between universities and related ministries, as well as the analysis of satellite and aerial images in Cambodia; and 5) organizing annual workshops in Cambodia with French experts and partners. To this end, in May 2024 the laboratory organized and launched in ITC an annual national conference to bring together all those involved in remote sensing in Cambodia (https://kheobsday2024.sciencesconf.org/).
