Desenvolvimento inicial DE Pachira aquatica Aubl. submetida a diferentes concentrações de rejeito de mineração de cobre da mesorregião sudeste paraense

Abstract

Mining plays a role of great importance for the Brazilian economy, however, this activity has led to soil contamination by potentially toxic metals, such as copper, and when an area reaches high levels of contamination, vegetation suppression may occur, and an option for the revegetation of areas contaminated by copper in the soil are native forests. The study aimed to evaluate the initial development of Pachira aquatica aubl. subjected to different concentrations of copper mining waste from the southeastern mesoregion of Pará. The experiment was conducted in a greenhouse, at the Federal University of the Amazon (UFRA), for a period of 210 days, in a completely randomized design, with five treatments and six replications , with two types of copper mining waste incorporated into the soil and two dosages (T1: control; T2: 30% Cu from Parauapebas; T3: 30% Cu Canaã dos Carajás waste; T4: 100% Cu from Parauapebas; T5 : 100% I reject Cu Canaã dos Carajás). The following parameters were evaluated: Height, stem diameter, number of leaves, Falker a and b chlorophyll index (ICFa and ICFb), aerial and root dry mass. Data analysis was carried out using the Tukey test at 5%. At 210 days, the results showed that the quality of the Pachira aquatica Aubl. are negatively affected by the copper doses tested, reducing their development in all evaluated parameters compared to the control. Among the plants subjected to waste, T3 obtained the best average of the evaluated parameters. Despite the reduction in its development, the species Pachira aquatica Aubl. achieved a high survival rate and can be an alternative in the revegetation of degraded areas, since the native tree species adapts to the specific environmental restrictions of the area where it will be introduced. Keywords: Heavy metal; ground contamination; tolerance; recovery of degraded areas.