Wild Olive Tree Mapping: Extent, Distribution and Basic Attributes of Wild Olive Tree in Al-Baha Region, Saudi Arabia, Using Remote Sensing Technology

This study provides a detailed overview of the extent and distribution of wild olive trees in Al-Baha region according to neighbouring tree species. The study area was concentrated along the Sarah mountainat Al-Baha region, encompassing the districts Al-Qura, Al-Mandaq, Al-Baha, the southern part of Baljurashi, and a small portion of Qelwa, Mekhwa, and Al-Aqiq districts. This indicates that the wild olive prefers to grow in high foggy mountain conditions, which a previous study determined as a medium-high vegetation density zone. The information extracted from the high-resolution PLEIADES satellite image reveals that the districts of Al-Mandaq and Al-Baha have a higher density of wild olives with more juniper neighbouring. On the other hand, the districts of Al-Qura and Al-Baljurashi have a lower density of wild olives but more acacia neighbouring. Meanwhile, the districts of Al-Aqiq, Qelwa, and Mekhwa have the least density of wild olives with more juniper neighbouring; however, Qelwa has more other species neighbouring. Further analysis of the imagery by automatic measurement of olive trees found that the wild olive tree associates its occurrence with certain species. The neighbouring species was identified within a five-meter radial distance from wild olives. The result indicates that juniper (40.2 %) and acacia (36.0 %) are the two main species that neighbour wild olives, with acacia found more dominantly in both the districts of Al-Qura and Baljurashi. Distinctly, Qelwa was found to have many other as neighbouring species (42.3 %). The overall accuracy of the interpretation of species was 89.2 %, with the producer and user accuracy for wild olive interpretation being 93.7 % and 88.3 %, respectively. This information will be essential to identifying the landscape preference of wild olives in the Al-Baha region.