Evaluation of salinity intrusion in arable lands of Al-Batinah coastal belt using unmanned aerial vehicle (UAV) color imagery

Salinity by seawater intrusion due to excess groundwater pumping for irrigation is a major environmental challenge in the coastal areas of the sultanate of oman. increasing salinity levels moving inward the arable lands is happening in a rapid manner. thus, salinity needs to be evaluated and quantified using a fast and accurate method. the objective of this study was to estimate salinity intrusion in al-batinah coastal belt using color aerial imaging. the study was conducted in five randomly selected sites at increasing distances from the seashore of al-suwaiq area in al-batinah region of northern oman. color aerial images were acquired for each site with an unmanned aerial vehicle (uav). images were enhanced by orthorectification in envi software. a green leaf index (gli) was obtained from each site image using matlab software. image analysis results were compared with the results of analyzed soil and water samples taken for ground-truth verification. there was a strong negative correlation between the distance from the seashore and the soil ec of each site (r = -0.95). similarly, the mean value of gli increased as the salinity levels decreased, r= -0.96 and -0.92 for soil ec and water ec, respectively. we demonstrated the possibility of the use of color images taken by a uav to accurately quantify the effect of soil salination on vegetation along the costal belt.