Desempenho de Cordia trichotoma (Vell.) Arrab. ex Steud. em diferentes sistemas silviculturais

Abstract

The primary interest of this research is to investigate whether Cordia trichotoma (louro-pardo) due to its adaptive phenotypic plasticity is capable of expressing its full potential and exhibiting greater variation in growth parameters when cultivated under different silvicultural systems. The objective of this study was to describe the dendrometric and morphometric behavior of louro-pardo across different silvicultural systems in the Dois Vizinhos region of Paraná. The research was conducted on five silvicultural systems involving louro-pardo: Silvopastoral System (SS), Urban Tree Area (AAU), Multistrata Agroforestry (AFM), Homogeneous Plantation (PH), and Forest Restoration Area – Nucleation (ARF-NU). The first two systems were 11 years old, while the latter three were 9, 13, and 14 years old, respectively. A simple random sampling method was used for the forest inventory, comprising five treatments with replication counts ranging from 6 to 95, totaling 186 trees of the specie. Data collection took place between February and June 2024. The dendrometric and morphometric variables analyzed were: total height, diameter at breast height (DAP), crown length (CC), crown diameter (DC), cylindrical volume (V cil.), vitality, stem tortuosity, tree sociological position, light availability, crown projection area (A), crown volume (VC), crown ratio (PC), slenderness degree (GE), crown projection index (IS), crown spread index (IA), and crown form factor (FC). Data processing was performed using Excel®, while multivariate analysis specifically Principal Component Analysis (PCA) and discriminant analysis was conducted using the RBio® statistical software. Significant diferences were observed in the dendrometric data of C. trichotoma across the different silvicultural systems. Trees located in the Urban Tree Area (AAU) exhibited superior performance compared to the others, owing to spacing and silvicultural treatments. Trees in the Multistrata Agroforestry System (AFM) achieved the highest mean values for morphometric indices: Slenderness Ratio (GE) 377.88% higher than the lowest value Salience Index (IS) 181.82% higher and Crown Form (FC) 63.95% higher. The results of this study underscore the importance of tailoring management practices to the characteristics of each system, taking into account the interaction between canopy structure, light availability, and the needs of the growing species.