This image is a montage of four journal covers from Acta Limnologica Brasiliensia, arranged side by side. Each cover follows the same format: a blue header with the journal's title at the top, and below, the specific cover image for the edition. 1. First cover, on the left: A landscape of a large, calm lake, bordered by rocky mountains with sparse vegetation. 2. Second cover: A dense, lush forest with tall trees and a stream of clear, transparent water winding through rocks. 3. Third cover: A close-up, macro photograph of an aquatic organism - a small, transparent, light brown crustacean with visible internal details. 4. Fourth cover: A rapid flowing over a bed of large stones and rocks. The water cascades powerfully, creating foam.