Influence of environmental variables on stream fish fauna at multiple spatial scales

Autor: Nara Tadini Junqueira, Diego Rodrigues Macedo, Rafael Couto Rosa de Souza, Robert Mason Hughes, Marcos Callisto, Paulo Santos Pompeu
Jazyk: angličtina
Předmět:
Zdroj: Neotropical Ichthyology, Vol 14, Iss 3
Druh dokumentu: article
ISSN: 1982-0224
DOI: 10.1590/1982-0224-20150116
Popis: ABSTRACT Effects of environmental variables at different spatial scales on freshwater fish assemblages are relatively unexplored in Neotropical ecosystems. However, those influences are important for developing management strategies to conserve fish diversity and water resources. We evaluated the influences of site- (in-stream) and catchment-scale (land use and cover) environmental variables on the abundance and occurrence of fish species in streams of the Upper Araguari River basin through use of variance partitioning with partial CCA. We sampled 38 1st to 3rd order stream sites in September 2009. We quantified site variables to calculate 11 physical habitat metrics and mapped catchment land use/cover. Site and catchment variables explained > 50% of the total variation in fish species. Site variables (fish abundance: 25.31%; occurrence: 24.51%) explained slightly more variation in fish species than catchment land use/cover (abundance: 22.69%; occurrence: 18.90%), indicating that factors at both scales are important. Because anthropogenic pressures at site and catchment scales both affect stream fish in the Upper Araguari River basin, both must be considered jointly to apply conservation strategies in an efficient manner.
Databáze: Directory of Open Access Journals