Eichhornia crassipes (Mart.) Solms (aguapé): vilã ou aliada na conservação dos ambientes aquáticos continentais?

Eutrophication, a process intensified by human activities, causes environmental and economic damage. Aquatic macrophytes, such as Eichhornia crassipes(Mart.) Solms (water hyacinth), are excellent indicators of this problem. Despite its importance in water cleaning, water hyacinths are often seen as the cause of problems, rather than a contributing factor.This study aimed to understand the ecological properties of E. crassipes(Mart.) Solms, especially its relationship with eutrophication and the resulting socio-environmental and economic implications. A review of the scientific literature from 2000 to 2022 was conducted, selected from the CAPES Periodicals Portal and Google Scholar, on biological, environmental, social and economic aspects related to E. crassipes(Mart.) Solms, as well as a diagnosis of the situation in the Poti and Parnaíba rivers, in the urban perimeter of Teresina, Piauí, Brazil. E. crassipes(Mart.) Solms has a complex relationship with the environment. On the one hand, it is considered an invasive species with a great capacity for adaptation and reproduction, capable of causing significant damage to aquatic ecosystems. On the other hand, it has characteristics that make it an important tool for environmental recovery, given its high phytoremediation potential. In the urban context of Teresina, E. crassipes(Mart.) Solms is presented asa key species, both as an indicator of water quality and environmental recovery and as a cause of negative impacts, such as obstruction of navigable waterways and loss of biodiversity. E. crassipes (Mart.) Solms is essential for the recovery of water bodies, but its indiscriminate removal can cause environmental damage. The management of this plant requires a balance between its benefits and its negative impacts.