Natural variation of physical-habitat conditions among least-disturbed streams of a neotropical river basin in Brazil

• DOI: 10.1016/j.watbs.2022.100091
• Publication Date: 2022-11-04T03:01:48Z
• Authors: Yuri Malta Caldeira; Ruanny Casarim; Paulo Santos Pompeu
• Keywords: Elevation (ballistics)

The determination of natural variation in physical habitat conditions and the establishment least-disturbed reference standards is important for ecosystem conservation. Tropical regions hold most global freshwater diversity, nevertheless little known about their habitats. We calculated 255 metrics 31 stream sites five protected areas Brazilian São Francisco River basin to identify variable characteristics among tropical streams areas. performed principal components analyses (PCA) find relevant ordination following categories: water quality (2); substrate (7); fish shelter (6); riparian vegetation (9); channel morphology (7). used distance-based linear models (DISTLM) test how much these could be explained by geographic position, average elevation, discharge sites. best statistically significant 42% (33% position; 9% elevation), 26% (22% 4% discharge), 23% (14% 17% (9% 8% 14% (7% 7% elevation) variation. Thus, regional features (e.g. geology climate) related position are greatest importance, followed elevation determining characteristics. Therefore, we suggest that should set same landscape with similar discharge.