ESTRUTURA, DINÂMICA E CORRELAÇÕES AMBIENTAIS EM UM FRAGMENTO DE FLORESTA OMBRÓFILA MISTA EM RESERVA DO IGUAÇÚ, PR

Abstract

The present study aimed evaluated in a fragment of Araucaria Forest, located in Reserva do Iguaçu - PR. The fragment has 4800m ² and was subdivided into 48 plots of 10m x10m (100m ²), the permanent portion in was installed in 2007 (DAP ≥ 5 cm) and remedida the years 2009 and 2012. Measurements were found in total 57 tree species, distributed in 24 family and 45 genus. The species with the highest importance are: M. stipitatum, A. niopoides, C. vernalis, D. sorbifolia, S. romanzoffiana and S. commersoniana individuals with high density in the area. The annual periodic increment was rated 0.57 m². ha.year -1 in the first period (2007-2009) and 0.65 m². ha.year-1 for the second period (2009-2012). The annual rate of mortality of individual was higher than the ingress. The subplots were grouped by cluster analysis and later with data from the first made to factor analysis, thus group the plots into three groups. Group 1 has the preferred species Sebastiania commersoniana, group 2 is the characteristic Dalbergia frutescens as indicator species and group 3 has as indicator species Albizia niopoides and Machaerium stipitatum and Diatenopteryx sorbifolia as preferred species. Environmental parameters evaluated were the chemical and physical soil compaction, slope, stoniness, depth and rocky. The Pearson's correlation indicated a correlation between some environmental variables. The principal components analysis found high negative correlation between sand and clay and between Magnesium and Phosphorus. The Monte Carlo test correlated species-environmental variables at 1% for axis 1, which belong environmental factors Calcium and Phosphorus. The second axis also used in the graphic presentation shows how factors most relevant depth and sand. The two axis together explain only 12.8% of the population variance. With the interpretation of the analysis graphic CCA can deduce that S. commersoniana as preferred species has strong correction with the variables measured in this work. The species D. frutencens that characterizes the second set of plots cluster is correlated with depth, has a greater incidence for deeper soils, more compact and less stony. The species A. niopoides and M. stipitatum have high correlation with soil chemical factors such as calcium, phosphorus and occur over rocky terrain and greater slope.