Construction CGHs and the decline of freshwater sponges (Porifera - Demospongiae)
the case of the Mourão River, Paraná, Brazil
DOI:
https://doi.org/10.5016/geografia.v51i1.19510Abstract
Freshwater sponges are sessile metazoans that attach to submerged substrates. This study presents an inventory of sponge species in the Mourão River, a left-bank tributary of the Ivaí River in Paraná State, Brazil, conducted between 2023 and 2025, and compares it with a 2011 survey. Species were identified based on spicules preserved in sediments. In 2011, three species were recorded: Oncosclera navicella, Oncosclera schubarti, and Tubella repens. The current survey found only two species — O. navicella and T. repens — and sediment analysis did not allow species-level identification in all cases. Between 2011 and 2025, two small hydropower plants (CGHs) were built in the area. The results suggest these constructions have negatively impacted sponge populations, evident in reduced species richness and signs of poor, incipient growth.
Downloads
Published
Issue
Section
License
Copyright (c) 2026 GEOGRAFIA

This work is licensed under a Creative Commons Attribution 4.0 International License.
The authors maintain the copyright and grant GEOGRAFIA the right of first publication, with the articles simultaneously licensed under the Creative Commons BY 4.0 License, which allows sharing and adapting the articles for any purpose, as long as appropriate credits and provisions of image rights, privacy or moral rights. Other legal attributions can be accessed at: https://creativecommons.org/licenses/by/4.0/legalcode.en.
Geography, Rio Claro, SP, Brazil - eISSN 1983-8700 is licensed under the Creative Commons BY 4.0 License.


