Estimation of the Leaf Area Index and Light Intensity in a Brazilian Tropical Forest Fragment

Abstract

In order to apply techniques aimed at the restoration and recovery of forest fragments, it is necessary to understand the ecological succession of the respective biome and the factors influencing its dynamics. Luminosity is one of the key factors for comprehending the cycle of native forests, influenced not only by climatic seasonality but also by the canopy structure and forest strata. The Leaf Area Index (LAI) is directly linked to plant growth conditions. The objective of this study is to map the distribution of LAI in the canopy of a Mixed Ombrophilous Forest fragment using non-destructive methods and to quantify luminosity. The research was conducted around the University Campus of the State University of the Midwest - UNICENTRO, in the municipality of Irati, Paraná, Brazil. These variables underwent numerical terrain modeling using the free software SPRING, resulting in two spatial representations, each containing four classes for each variable. The data underwent statistical analysis using Spearman's and Pearson's correlations, resulting in coefficients of 0.89 and 0.9, respectively. Thus, both variables are strongly linked, with LAI as the independent variable and luminosity as the dependent variable. The use of numerical terrain modeling for the variables proved appropriate, as it allowed the expression of visual features that can be observed within the experimental area.