Toxicological impact of elutriate from wooded soil with the exotic plants Pinus spp. and Eucalyptus spp.

The presence of exotic species of plants in a region is associated with anthropogenic activities due to their economic and commercial benefits. When these exotic species hinder the development of native species, they are considered invasive. In Brazil, two species stand out: Pinus spp. and Eucalyptus spp. Their presence within ecosystems may result in environmental imbalances caused by allelopathy. The allelochemicals released by these invasive species can enter the environment through rainfall, decomposition of plant material, root exudation, and volatilization. The high solubility of phenolic compounds produced by these plants allows them to reach water bodies and potentially affect aquatic organisms. In light of this, a toxicological evaluation was conducted by exposing Daphnia magna, Aliivibrio fischeri, Landoltia punctata, and Lactuca sativa seeds to soil elutriates from areas with exotic and native vegetation. The samples were collected in close proximity, with the primary difference being the type of vegetation cover. Upon characterization, the soil covered by native species was found to contain higher levels of organic matter and moisture, whereas the soil with exotic species appeared drier. Overall, the toxicological evaluation revealed that elutriates from native vegetation induced greater toxic effects on the aquatic organisms D. magna and A. fischeri. Conversely, elutriates from exotic vegetation showed lower concentrations of total phenolic compounds but still exhibited toxic effects on the development of L. sativa seeds and caused notable structural damage to the aquatic macrophyte L. punctata.. This study highlights the importance of investigating reforested areas dominated by exotic species to better understand the potential environmental impacts caused by invasive plants.