Levantamento batimétrico em área de fundo móvel: Estudo em Paranaguá

Abstract

Vegetation plays an important role in water regulation, erosion control and siltation of waterways. The following study aims to conduct an integrated environmental diagnosis of springs by mapping the floristic composition and geoprocessing the watershed of the Igarapé do Educandos in Manaus (AM) in the period from August to December/2019. The springs are located in the Federal Institute of Amazonas (IFAM-CMZL) in the eastern zone of Manaus, coordinates 3005'05.93 "S and 59056'10.78 "O, with approximately 1148.92 m2 and at IFAM-CMDI, in the Industrial District (southern zone of Manaus), coordinates 3008'08.87 "S and 59058'40.32"0, with approximately 369.566 m2. The methodologies used were differentiated due to the layout of the springs. At IFAM-CMZL, a 50 m radius around the springs was estimated, divided into four plots of 500 m² (10 x 50 m2) or 2000 m2 or 0.2 ha. Shrubby-arboreal individuals with a diameter at breast height (DBH at 1.30 m from the ground) ≥ 10.0 cm were inventoried. In the IFAM-CMDI area, a plot of 10 x 100 m, total 1000 m2 , and another of 20 x 50 m, total 1000 m2, equivalent to 0.2 ha, were established around the spring. The shrubs and the trees were surveyed with diameters at breast height (DBH at 1.30 m from the ground) ≥ 10.0 cm. Among the phytosociological analyses were calculated the importance value indices (IVI), elaboration of the speciesarea curve and diversity index of Jentsch's mixing coefficient (QM). Based on the results, 126 individuals, 50 species distributed in 23 botanical families and 42 genera were detected in IFAM-CMZL. The families with the highest number of species were: Fabaceae (8); Burseraceae (6); Moraceae (5) and Euphorbiaceae (4). In the areas sampled at IFAM-CMDI, 107 individuals, 34 species, distributed in 17 families and 42 genera were detected. The most representative families were Arecaceae (6), Fabaceae (5), Moraceae (4) and Burseraceae (3). In regards to land cover, the work was developed in 2 stages: the first was carried out from the acquisition of data from the MapBioma platform, for the years 1985 to 2018, with intervals of every 5 years and the second involved the acquisition and preparation of satellite images of the year 2019 in the QGis program for the determination of the NDVI (Normalized Difference Vegetation Index). Regarding the results it was observed that in 1985 in the springs of IFAM-CMZL and IFAM-CMDI, the forest formation represented about 62% and 63% respectively, for all the land cover and usage of the areas under study. As of the year 2018, the forest formation represented about 49% in the area of IFAM-CMDI and 73% in the area of IFAM-ZL. A vegetation gain of about 11% and a decrease of pasture was observed as of the year 2000 in IFAM-CMZL, by regeneration of the vegetation, while in the area of IFAM-DI a decrease for 49% of the forest formation in the period from 1985 to 2018, representing a loss of 14% of forested area, thanks to the increase of urban infrastructures and a higher population density in the said period.