Shoreline evolution of Valencia lake and land use and land cover changes in Zamora municipality, Aragua state, Venezuela, period 1986-2016

Abstract

This study was conducted to estimate the land use and land cover (LULC) changes from 1986 to 2016 at Zamora municipality in Venezuela. Landsat 5 TM, Landsat 7 ETM+, and Landsat 8 (OLI/TIRS) images were obtained to evaluate the shoreline dynamics of the Valencia lake and the magnitude of LULC changes. The images were processed and classified through the object-oriented approach in eCognition Developer 8, for collecting ground-truth data was used Google Earth Engine Python API and Excel software for accuracy assessment. ArcGIS 10.4 and QGIS 2.18 were employed for spatial analysis. It was found that scrublands and farmlands experienced important reductions in area, 13029 ha, and 818 ha respectively, whereas forest, built-up, and water bodies classes showed remarkable increments in area, 11792 ha, 1482 ha, and 634 ha correspondingly. The Valencia lake shoreline underwent an upward trend wherein more than 50% of its raising occurred during the last two study years (2003-2016). It was also observed that land use and land cover changes prompted conflicts with other land uses, 337 ha of lands with high potential for crop yields were affected by the lake shoreline increment and built-up areas grow at a rate of 81 ha /yr. for the last two study years (2003-2016) mainly on lands with high potential for agricultural use.