Caracterização do igarapé Regaço Ecológico e de sua ictiofauna

Abstract

The study aimed to perform the environmental characterization and ichthyofauna of the Regaço Ecológico creek. The monthly samples of plant, soil, water, transparency, depth, dissolved oxygen and fish were performed from July 2020 to June 2022 in the creek. The plant material samples were collected and taken to the Laboratory of Zoobotanica to be dried in an oven, made exsicatas and made the identifications. For the collection of soil samples, a PVC pipe (100 mm) and 1kg plastic bags were used, identified and sent to the Soil Laboratory - FCA/UFAM for grain size analysis and sent to the Aquaculture Laboratory - LAqua/ICSEZ for pH and temperature analysis. pH and water temperature were performed with the aid of pH meter and digital thermometer. For the measure of water transparency was used the Secchi disc, for depth a millimeter ruler with dimension 1.2x4x600cm, for dissolved oxygen a colorimetric kit of the brand Labcon Test and for the capture of fish was used a puçá, with 1 mm mesh between us. Twenty-six species of plants distributed in 13 families were collected in the stream: Apocynaceae, Chysobalanaceae, Cyperaceae, Euphorbiaceae, Fabaceae, Lentibulariaceae, Melastomataceae, Nymphaeaceae, Onograceae, Passifloraceae, Poaceae, Rubiaceae e Sapindaceae. For the soil granulometry, the sand granulometric fraction presented the highest average (95.62%), followed by the silt fraction (3.32%) and clay (0.99%). The water temperature varied between 26,1 and 35,2 ºC, with an average of 28,78+2,82 ºC and for the soil presented variation from 26°C to 35,5 °C with average of 28.95 2.91 C. For soil and water pH little variation was observed during all months of collection, 4,35 to 5,88 with mean of 5,13+0,54 and 4,35 to 5,92 with mean of 5,04+0,48, respectively. Transparency (89,20+25,45 cm), dissolved oxygen (9,31+2,16 ppm) and depth (236,41+169,51cm), showed the respective means. Twenty species were identified, distributed in three Orders: Characiformes, Perciformes e Gymnotiformes. The data of the species found and environmental variables were analyzed through descriptive analysis.