Investigating water body changes using remote sensing water indices and Google Earth Engine: Case study of Poldokhtar wetlands, Lorestan province

Wetlands are the most important natural ecosystems on the earth, and assessing changes in them is one of essential nessesties in natural resource management of this valuable natural ecosystem. The aim of this study is to investigate water body changes using remote sensing water indices and Google Earth Engine (GEE) in study area of Poldokhtar wetlands, Lorestan province. Remote sensing water indices includes AWEInsh ،AWEIsh، NDWI، mNDWI، NDWI plus VI، mNDWI plus VI and LSWI plus VI that were used TM, ETM+ and OLI Landsat satellite images, and Google Earth Engine were applied Landsat Water Product data. The results demonstrated temporo-spatial distribution of water body changes in the study area and they were compared to real data indicating AWEIsh and AWEInsh with overall accuracy of 99.39 and 99.19 and Kappa coefficient of 0.94 and 0.91 were the best water indices among all in enhancing water bodies, furthermore, GEE results showed overall accuracy of 87 and kappa Coefficient of 0.86. These results indicate that water indices and GEE are useful tools in detection of increasing and decreasing trends in water bodies that can assist planner and policy makers in protecting and managing natural resources in the study area.