Floristic-Structural Variation of Natural Regeneration Along Different Topographic Positions of an Ecotonal Forest in Santa Catarina, Brazil

Abstract

-Studies on the natural regeneration of tree species communities are important for providing information on forest development capacity. This research aimed to evaluate the floristic-structural variations of the tree regenerative component along a topographic gradient in an ecotonal area between a Mixed Ombrophilous Forest and a Deciduous Seasonal Forest of Santa Catarina, Brazil. 30 sampling units of which all regenerating tree species individuals have been identified were allocated in the forest fragment. The sampling units were then distributed along a topographic gradient into lower, intermediate and upper sectors. Abundance, richness, Shannon's diversity index (H') and Pielou's evenness index (J) have been determined for both the whole community as for each sector. The community floristic-structural organization was verified by the means of the nonmetric multidimensional scaling (NMDS), the indicator species analysis and the permutational multivariate analysis of variance (PERMANOVA). Abundance differences among sectors were analyzed through the KruskalWallis test with post hoc multiple nonparametric test while richness differences were verified through rarefaction. Regenerating individuals density in the upper sector [129 (21.300 ind.ha -1 )] was lower than both in the lower [401 (63.800 ind.ha -1 )] and intermediary [241 (36.300 ind.ha -1 )] sectors. There was variation in the floristicstructural composition (p < 0.001) among topographic positions; the lower sector was the most distinct one and showed the highest number of indicator species.

Tree community dynamics in a forest adjacent to the reservoir of a hydroelectric power plant in the southern Brazilian Atlantic Forest

“…Considering the most abundant populations by sector, a structural variation according to their location can be noticed despite the general pattern of losing individuals and gaining basal area. Former studies carried out in the same area also indicated floristic-structural variations in the community related to the sectors location for both the adult (Souza et al 2015) and the regenerative (Souza et al 2017a) components. By investigating the functional aspects of the area under study, Souza et al (2017b) likewise demonstrated that in the lower sector prevails a community with resources acquisition traits, however, in the slope intermediate and upper sectors conservative traits prevail.…”

Effects of the Environment and Spatial Factors on the Regeneration of Araucaria Forest Fragments, Southern Brazil

“…Kuntze), with emphasis on other species of the families Lauraceae and Meliaceae (Kersten et al, 2015). In general, the distribution of this forest type is associated with intrinsic soil, geomorphological and climatic conditions, as well as being influenced by extreme environmental factors (i.e., storms, frost, fires) (IBGE, 2012; Higuchi et al, 2016;Souza et al, 2017).…”

“…In this sense, in the present study we analyze two main questions: (1) Which environmental factors influence the distribution patterns of regenerative species? We expect to find a great effect of soil and canopy opening in determining floristic composition, because these are well known to be the main factors conditioning changes in the composition of vegetation in the Atlantic Rainforest at local scales (Higuchi et al, 2015(Higuchi et al, , 2016Souza et al, 2017;Maçaneiro et al, 2019). (2) Is the spatial structure of the community related to regenerative species and environmental factors?…”