Potencial fitorremediador de Erythrina velutina Willd. cultivada em solo contaminado com cobre e incorporação de biocarvão

Abstract

In recent decades, researches have been demonstrating how heavy metals have the ability to stick and accumulate in the environment, being harmful to human health and the environment. Once the contamination of the soil happens, some actions are needed for the soil’s remediation.The objective of this reasearch was to evaluate the growth of the Erythrina velutina Willd seedlings cultivated in contaminated soil with copper and biochar. The first experiment was conducted for 21 days and the second for 69 days and analyzed the following morphological variables: Aerial Part Height (APH), Stem Diameter (SD), Aerial Part Increment (API) Stem Diameter Increment (SDI), Root’s Length (RL), Aerial Part Dry Mass (APDM), Root Dry mass (RDM), Total Dry Mass (TDM), Ratio between Aerial Part and Stem Diameter (AP/SD), Leaflet Numbers (LN), Leaflets Area (LA), Dickson Quality’s Index (DQI), Translocation Index (TI), Water Content in Aerial Part and Root (WCAPT) and Copper Concentrations in plant’s tissue (aerial and root part) through the EDS (energy dispersive spectroscopy).The collected data were submitted to a variance analysis (ANOVA) (p < 0,05) and Tukey test (p < 0,05). In the first experiment, it was observed that the biochar didn’t reveal any positive effect and didn’t benefit the growth of the seedlings. This result can be explained by the characteristics of biochar, influenced by the raw material and the carbonization process. In addition, the biochar could also have increased the cation exchange capacity and, consequentially, decreased Copper leach, enabling it to be more available to the seedlings. As for the second experiment, there was no significant difference of the 5% morphological variable of the seedlings, but it didn’t have Copper in the tissues analyzed, which could mean that the plant didn’t absolve as a result to a possible leach and/or an adsorption of the feedstock. Therefore, it is necessary complementary researches to evaluate the potential of Erythrina velutina Willd in projects of phytoremediation in soils contaminated by Copper.