The Incidence of Slope as a Factor in the Morphological Distributions of the Shallow Lakes on Sandy Hills (Corrientes, Argentina)

In the Corrientes Province, the Paraná River ran through different sections of the alluvial fan, forming sandy hills. Currently, over sandy hills a large number of small circular shallow lakes is developed. They were classified considering a qualitative description of aerial photographs and satellite images. However, the studies about the distribution, size, morphometric features and functionality of the shallow lakes only confined to specific case studies. Therefore, in order to obtain further information from the region that contains these water bodies, greater knowledge about the shallow lakes will be generated. The results of this paper allowed knowing the distribution of 38,926 shallow lakes, which account for 20% of the landscape surface. 72% of the total of shallow lakes has a circular shape and the remaining 28% has sub-circular and triangular shapes. An E-W distribution of shallow lakes is observed, where the most complex forms are distributed to the East and the simple/circular shapes increase toward the West. Major topographic differences allow greater lagoon interconnections and therefore complex shapes. On the contrary, western flatter reliefs contributes to the segmentation of lagoons. Statistical analysis of the morphometric variables of the shallow lakes according to the topography of the sandy hills, has classified in different sections mega alluvial fan of the Parana river.