Yarı kurak bölgelerde sentetik açıklıklı radar (mikrodalga) görüntüleri ile toprak neminin tahmini

Abstract

Spatial and temporal distribution of soil moisture is a key parameter for agricultural applications at watershed level such as drought monitoring, crop irrigation scheduling, and yield estimations in arid and semi-arid regions. Moreover, radar satellite imagery systems have been used to figure out soil and vegetation distributions spatially and temporally for various regions. Estimation of surface soil moisture using active microwave sensor systems is among useful information for researchers, conservation planners, and decision makers pursuing sustainable use of natural resources. This study was carried out at the soils of selected sixty-four square kilometers test site in Altinova State Farm. It was aimed to determine the relationship between the surface soil moisture and the backscatter values of SAR images (Radarsat-2) obtained four different times. To that end, four SAR images (4 Radarsat-2 images) from Altinova State Farm were used. Surface soil samples were collected simultaneously from 0-20 cm depth at 730 different points with 250 m-intervals, and soil moisture was determined using gravimetric method throughout the study area. In regards to each sampling period, surface soil moisture distribution maps were produced using ordinary kriging method. Considering the soil moisture distribution maps the data obtained in August indicated the most alterations in the surface soil moisture throughout the study area in comparison to the other sampling periods. Therefore, it was revealed that the relationship between backscattering (obtained from Radarsat-2 data in August, 2012) and soil moisture content was better than the other SAR data results (r=0.506, p<0.05).