Evaluation of spatial variations of vegetation and surface temperature using Landsat and midsize images, case study: Fars Province, 1967-2017

It is very important to be aware of the quantitative and qualitative characteristics of land changes in environmental planning, land management and sustainable development. At present, the use of vegetation map is one of the important pillars in generating information for macro and micro planning. In this study, temporal and spatial variations of vegetation were used in Fars Province. The data from Landsat satellite were calculated from OLI and ETM sensors during a thirty years period (1986-2016) and the NDVI index was measured. Quantitative changes of vegetation were also classified. The index is classified into three classes, including rich, poor and vegetation-free. The temperature changes of the ground level in the study period were also calculated using MODIS images. Results showed quantitative and qualitative changes of vegetation over 30 years for the studied area, so that the vegetation-free areas increased by 107. 49 ha and the areas with poor vegetation decreased by 366.56 ha and the rich vegetation cover has dropped by 455.55 ha. The largest reduction in the area was made on lands with rich vegetation. The MODIS images revealed that surface temperature has increased in the province. The temperature variation is more than 3 degrees (from -2.8 to 0.96° C) and it was observed that the highest temperature reduction was in the eastern and heading to the province. Finally, in order to investigate the relationship between vegetation and LST, the annual isobars were plotted along with the difference in NDVI in the studied period. The results showed that in most areas the vegetation cover was denser with lower temperatures.