Mapping of hydromorphic grasslands in the 'Catarinense' highlands by hydrologic modeling

Abstract

Grassland ecosystems interspersed with fragments of Araucaria Forest are common in the 'Catarinense' highlands. There are strong indications that the non-hydromorphic steppes, on mineral soils, result from forest exploitation or the impediment to its advance - less than 10% of the forest area remains nowadays. However, hydromorphic grasslands can be found exclusively on Organosols occupying special region features, and they seem to be natural, although impacted. In this study, we aimed to map the hydromorphic grasslands from data collected in the field compared with the maps of hydrological factors produced mainly by the Digital Elevation Model and the drainage network. Histogram and correlation analyses were performed. Flow length longer than 400 m is positively correlated with the depth of hydromorphic zones. The level sequences and plains are related to the hydromorphic areas, but the scale of this study does not accomplish their final characterization. Complementary researches approaching the spatial analysis of relief are necessary.

'Catarinense' highlands; grasslands; Mixed Rain Forest