Caracterização estrutural e condições ecofisiológicas de fragmento urbano de Floresta Atlântica usando VANT e imagem de satélite.

Abstract

Over the years, the Atlantic Forest vegetation has been subjected to a progressive suppression process, mainly by anthropogenic measures, directly modifying the surface and causing irreparable damage to the biodiversity of this highly important social, economic and environmental ecosystem complex. In addition, these anthropic interventions further increase the fragmentation process, which searches for knowledge regarding the ecophysiological condition of fragments of this vegetation, which are under the direct influence of anthropic effects, more relevant. Currently, a viable methodology to assess such conditions is analyses that use geoprocessing and remote sensing, which uses techniques that allow obtaining information about targets on the soil surface, assessing its spatial dynamics, estimating the height of structures, and analyzing land use and cover. Furthermore, through the Vegetation Indexes, it is possible to assess the ecophysiological condition of those being registered. Thus, the study aimed to characterize a structure and an ecophysiological condition of the vegetation of an urban fragment of the Atlantic Forest. A Unmanned Aerial Vehicles (UAV) flight was carried out over a Fragment of Dense Ombrophilous Forest in the Lowlands located in Recife - PE. These images classified the land use and cover; they estimated the number of Individuals in the Area and their Height. After that, high-resolution satellite images were slid to calculate the Normalized Difference Vegetation Index (NDVI) and the Green Chlorophyll Index (GCI). It was identified 482 non-study forest fragments, submitted to a different level of anthropization,similar to other areas of the same phytogeographic domain, oscilating between 5.14m and 33.46m height. The NDVI of the area ranged between -0.21 and 0.93, and all places where arboreal trees were identified, through photogrammetry analysis, mean ND values greater than 0.6, indicating that they are physiologically healthy. The GCI values at the points where arboreal trees were identified were above 2.37 g/m², and the highest values for this index were found in the most centralized region of the fragment under study. The value found was higher than that measured in crops. This study showed that photogrammetry is a viable method to measure the height of wanting trees, mainly due to the quality of the provided images. Moreover, the evaluation through the Vegetation Indices indicates that this vegetation is physiologically healthy and has a chlorophyll content (g/m²) estimated by the GCI, superior to homogeneous plantations of crops.