ESTRUTURA E DISTRIBUIÇÃO ESPACIAL DAS FLORESTAS RIPÁRIAS DO RIO PITANGUI, PARANÁ, BRASIL

Abstract

Pitangui is an antecedent river, a major right tributary of the Tibagi River, which crosses three municipalities along the East-Central region of the State of Paraná. Although being subjected to the same climate, Cfb of Köeppen, and same phytogeographic unit, temperate forest, its altitudinal differences and distinct litotipies represented by the Devonian Escarpment topographic slope, and the consequent separation between the Paraná plateaus, determine remarkable geo-pedo-hydromorphological differences. It was observed that the groundwater level variation and the soil composition are the main drivers of floristic and structural variations among these riverine forests. On the First Plateau (PPP), the Riparian Environment #1 is characterized by relief plan subject to permanent or periodic flooding with hydrophylous or hygrophilous vegetation over hydromorphic or semi-hydromorphic soils. The main species are Sebastiania commersoniana, Erythrina crista-galli, Symplocos uniflora, and Sebastiania brasiliensis. Yet in PPP, Riparian Enviroment #2 is an ecotonal area within Alagados Reservoir. This is a more elevated one, subject to few floodings, with mesophylous vegetation on no-hydromorphic soils, which main specie is Nectandra grandiflora. On the Second Plateau (SPP), Riparian Environment #3 is characterized by relief plan to slighltly undulating with mesophylous vegetation on soils preferably non-hydromorphic. The main species are Nectandra grandiflora and Eugenia uniflora. In all environments soils are ever acid with high contents of total carbon in the surface layers, as well percolation of phosphorus next to agricultural crops areas. The functional groups distribution among mesophilous, higrophilous, and hidrophilous species were good indicators of the ground water level flutuation. On a landscape scale, multiescalar phenomena are subordinated, as geological modeling determine ground water levels as well soils orign and distribution. These one drives the vegetation settlement. Integrated studies like this provide insurance subsidies for forest restoration programs in riparian environments