Wild Olive Tree Mapping Extent, Distribution and Basic Attributes of Wild Olive Trees in the Al-Baha Region using Remote Sensing Technology

This study provides detailed information on the extent and distribution of wild olive trees in the Al-Baha region. The study area, concentrated along the Sarah Mountain, encompassed the districts of Al-Qura, Al-Mandaq, Al-Baha, the southern part of Baljurashi, and a small portion of the Qelwa, Mekhwa, and Al-Aqiq districts. This indicates that wild olive prefers high, foggy, mountainous conditions, which a previous study determined to be a medium to high vegetation density zone. The information extracted from high resolution Pleaides satellite images reveal that in the 1, 991 km2 of the area studied, only 817 km2 (41 %) has wild olive trees. The Al-Qura district has the highest percentage, with 46.0 % covering 270 km2, followed by Al-Mandaq, (44.3 %, 150 km2) and Al-Aqiq (41.6 %, 69 km2). However, the district with the lowest population of wild olive trees is Qelwa (29.5 %, 24 km2). The automated calculation of geographic information system (GIS) crown polygons transformed from Pleaides imagery classification enumerated a total of 717, 894 wild olive trees at the study area or an average of 360 trees per km2. The Al-Mandaq district has the highest numbers, with 208, 034 wild olive trees, followed by Baljurashi (178, 801) and Al-Baha (161, 802), whereas the Al-Qura, Qelwa, Mekhwa Al-Aqiq districts have the lowest number of wild olive trees. These results show that the Al-Mandaq district has the densest wild olive population, with 613 trees per km2, followed by Al-Baha, which has 563 trees per km2. Meanwhile, the Al-Aqiq district has the lowest wild olive tree density, with only 22 trees per km2, followed by Al-Qura, which has 222 trees per km2. From maps, it was observed that most wild-olive-dense areas are located at the north-eastern Al-Mandaq, south-western Baljurashi, and at the boundaries of Al-Baha. The overall accuracy of the interpretation was 91 %, with producer accuracy and user accuracy being 93.7 % and 88.3 %, respectively. This information will be essential in identifying the landscape preference of the wild olive in the Al-Baha region