Ecosystems in desert areas are very sensitive and their protection is necessary. Nebakhs are one of these ecosystems in many parts of the world. These phenomena have a special importance in preventing desertification and their proper monitoring and management can be a way to preserve them. However, the difficulty of conducting field surveys and measurements in desert areas can hinder the collection of accurate, up-to-date and comprehensive information from these areas. Volunteered geographic information (VGI) from cheap drones and their operators can be very useful in this regard. But on the one hand, these drones usually only have RGB sensors, and on the other hand, the people who work with these drones do not have much access to commercial software. Therefore, using RGB-based indices and open source software can help a lot. In the current research, QGIS open source software is used to calculate RGB indices including NRI and RBD, NBI, MGRVI, GRRI, RGBVI, NGI, EXG, GLA, etc to extract information related to Nebkhas including canopy area and so on. The results show that UAV images and RGB indices, especially RGBVI, NGI and EXG, can help to extract properties of Nebkhas. The use of VGI data in the form of cheap UAV images and RGB indices in the framework of open source software has the ability to improve the process of monitoring and managing sensitive desert ecosystems such as Nebkhas in a good and accurate way.

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