MULTITEMPORAL EVALUATION OF VARIABLES DERIVED FROM OLI DATA FOR THE CHARACTERISATION OF ECONOMIC ACTIVITY IN THE NORTHERN DISTRICTS OF ENTRE RÍOS PROVINCE

Abstract

The objective of this work was to obtain simple figures for the characterization of the economic activity of the administrative districts belonging to the departments of the Entre Ríos Province, through the data derived from the spectral information obtained by the OLI sensor of Landsat 8, in the near red and infrared range. We used 19 mosaics of twoscenes, orbit 226 of Landsat 8 / OLI, year 2013 to 2016 of the northwest of the Entre Rios Province. The images show cultivated land in 17 districts corresponding to three Departments of the northwest of the Province. The areas are distributed from the coast of the Paraná River to the provincial center where agricultural activity is predominant. SAVI – The “Soil- adjusted Vegetation Index” was used because the province has a large proportion of dark soils. The main parameter for calculating the SAVI, the “L”, was extracted directly from the images. Its value was obtained from bare soil pixels in the humid season from the southern region of Federal Department, where the dark soils of the study area are located. The index was calculated for each district and the frequency of SAVI was obtained. The frequency data, for each district, were grouped and ordered by the DOY and these data served to form a two- dimensional frequency distribution, whose “x” was the value of the SAVI and “y” on DOY. The results show that the figures obtained from districts of the same department are similar, when compared to each other, and the differences increase from Southwest to Northeast, and these figures can be grouped from Southwest to Northeast, also, by their forms. The figures obtained in the districts of the Northeast have well defined sigmoid forms. All of them have an annual peak, and those obtained to the West present mixtures of forms characteristic of agricultural areas and livestock farming in native forest land with great dispersion in summer, in correspondence with the greater proportion of agricultural areas, harvested, prepared and in production. These simple diagrams can represent the main economic activities of districts and changes in the same. These diagrams could be of great value for the administration and planning of each Department.