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(Reference retrieved automatically from SciELO through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

When roads cross streams: fish assemblage responses to fluvial fragmentation in lowland Amazonian streams

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Gabriel L. Brejão [1] ; Fabrício B. Teresa [2] ; Pedro Gerhard [3]
Total Authors: 3
[1] Universidade Estadual Paulista “Júlio de Mesquita Filho”. Departamento de Zoologia e Botânica - Brasil
[2] Universidade Estadual de Goiás. Campus de Ciências Exatas e Tecnológicas - Brasil
[3] Embrapa - Brasil
Total Affiliations: 3
Document type: Journal article
Source: Neotropical Ichthyology; v. 18, n. 3, p. -, 2020.
Web of Science Citations: 0

ABSTRACT Roads affect biodiversity by increasing mortality rates, habitat loss, and natural landscape fragmentation. Poorly installed culverts can impound streams, changing the environmental conditions, and affecting aquatic communities. We evaluated the effects of road crossings on the taxonomic composition and functional structure of fish assemblages in lowland eastern Amazonian streams, Brazil. We tested the hypothesis that the presence of road-derived impoundments affects assemblage taxonomic and functional composition and structure. Two predictions were addressed: (1) Species and functional group composition will differ in impounded reaches in relation to lotic reaches; (2) Assemblages in downstream lotic reaches will be richer in species and functional groups in relation to upstream lotic and impoundment reaches. We sampled five streams crossed by roads presenting impoundment formation, conducted by visual census (day, dusk, and night) in 200 m line transects. Assemblage composition from lentic reaches was different from lotic reaches, and Shannon diversity from downstream reaches was different from upstream and impoundment, however, beta diversity partitioning between lotic reaches showed higher nestedness contribution, reinforcing the role of impoundment in limiting fish dispersal between lotic reaches. These results suggest that impoundments impose environmental and dispersal constraints to fish, affecting their longitudinal distribution in streams fragmented by roads. (AU)

FAPESP's process: 18/11954-9 - Fluvial networks as landscape connectors: does the riparian connection quality influence patterns on stream fish diversity?
Grantee:Gabriel Lourenço Brejão
Support type: Scholarships in Brazil - Post-Doctorate