Defining River Regional Landscape Classifications for Implementing Spatially Extensive Brazilian Stream Assessments

ABSTRACT Aim To determine whether regional classification—river typology or ecoregion—better captures the ecological variability of tropical stream ecosystems for biomonitoring purposes. Location Three hundred and forty‐eight streams located in the São Francisco, Mata Atlântica and Paraná hydrologic units, Minas Gerais state, southeastern Brazil. Time Period Data were collected between 2003 and 2019 as part of regional freshwater monitoring programs conducted by different research projects. Major Taxa Studied Benthic macroinvertebrate assemblages. Methods We evaluated two spatial and hierarchical classification systems: (1) river typology, based on climate, topography and lithology and (2) ecoregions, which consider natural features such as landforms, vegetation, land use and cover and hydrography, to explain variation in benthic macroinvertebrate assemblages. We asked: which landscape classification (i.e., river typology or ecoregion) was more effective at representing patterns in benthic macroinvertebrate assemblages for stream bioassessment in Minas Gerais state, Brazil? Results Level III Ecoregion was the most adequate regional landscape classification for benthic macroinvertebrate data, as it has a better ability to differentiate ecological patterns between groups. Main Conclusions Ecoregions offer more ecologically meaningful spatial units for classifying rivers in tropical regions such as southeastern Brazil. Our approach fosters alignment between scientific assessment, legal frameworks and environmental governance, thereby advancing more informed and effective conservation strategies for freshwater ecosystems.