Estrutura de fragmentos florestais urbanos de Manaus-Am: implicações para seu manejo e conservação

Abstract

It was analyzed ten forest fragments of Manaus city about its structure in the urban space. It was investigated about forest composition of fragments, estimations of horizontal structure parameters and dendometric parameters (basal area, biomass above the ground and carbon storage) of arboreal plants with DBH > 10cm, plus the perturbation history and management. It was account 3609 plants with DBH > 10cm, been recorded 256 species, 51 botanic families at 12 ha sampled (48 plots with 0.25ha). The Shannon index (H’) calculated with 10 fragments was 4.53. The fragment named SESC (13ha) showed the largest number of expected species (S) by the rarefaction curve, followed by AEROPORTO fragment (540 ha), CASTANHEIRAS (10ha), UFAM (600ha) and PARQUE DO MINDU (29ha). The VILAR CAMARA fragment (48ha), CAMPOS ELISIOS (18ha), SAUIM (98 ha), NUCLEO 23 (35ha) and SESI (52ha) showed the lowest number of expected species. The fragments structure it was analogous to their perturbation history and management, reveled different stages of forest regeneration. The fragments were classified like remnant native vegetation of Manaus because the similarity with Uper-Land Forest from the Amazon region about the forest composition and the estimations of horizontal structure parameters. The Arecaceae, Euphorbiaceae and Mimosaceae families were the most important ones. Demonstrated that is important the management of small fragments (less than 100ha), for to show expressive values of exclusive species richness species and botanic families in relation the largest fragments (more than 100ha). There was similarity about forest composition between the UFAM and AEROPORTO fragments and between PARQUE DO MINDU and VILLAR CAMARA. The estimation of number of individual for hectare, basal area, fresh phytomass above the ground and carbon, been 30 plots in each fragment sampled (IC 95%) were 291 ± 35.92 individual/ha, 10.81 ± 1.42 m²/ha, 196.26 ± 27.87 ton/ha e 58.88 ± 8.36 ton/ha. The SAUIM, VILLAR CÂMARA and PARQUE DO MINDU fragments showed the biggest number of plants for ha (385, 368 e 345, in order) and AEROPORTO, PARQUE DO MINDU, VILLAR CÂMARA and UFAM fragments the biggest estimation of basal area (14.45; 14.29; 12.73 e 12.27 m²/ha, in order) been that the lowest one were NÚCLEO 23, SESI and SAUIM (5.82; 7.87 e 8.74 m²/ha). It clear that is important to know about fragments history and to manage these areas to guarantee their conservation and the good environment condition for the Manaus city.