Influence of Land-Use Classes on the Functional Structure of Fish Communities in Southern Brazilian Headwater Streams

• Published in: Environmental management (New York) Vol. 65; no. 5; pp. 618 - 629
• Main Authors: Barbosa, Amanda Saldanha, Pires, Mateus Marques, Schulz, Uwe Horst
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.05.2020; Springer Nature B.V
• Subjects: Agriculture; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Composition; Detritivores; Divergence; Earth and Environmental Science; Ecology; Electrical conductivity; Electrical resistivity; Environment; Environmental changes; Environmental Management; Fish; Foraging habitats; Forest conservation; Forest management; Forestry Management; Land use; Nature Conservation; Physical characteristics; Physical properties; Silviculture; Species; Streams; Urban agriculture; Urban areas; Vegetation; Waste Water Technology; Water Management; Water Pollution Control; Water quality; Water temperature; Brazil; Anthropic disturbance; Urbanization; Forest; Agriculture; Functional traits; Functional composition
• ISSN: 0364-152X; 1432-1009
• DOI: 10.1007/s00267-020-01274-9

Changes in landscape composition caused by conversion of natural habitats into human-altered ecosystems can directly influence the physical characteristics of stream networks. Such impacts can modify the functional structure of fish communities, although the exact consequences of anthropic land-use changes can be context-dependent. This study investigated the influence of different land-use classes on the functional structure of fish communities in 32 headwater streams from southern Brazil. Trait composition and indices of functional diversity of the fish community were related to four land-use classes: native forest vegetation, silviculture, agriculture, and urban areas. Streams surrounded by larger areas of native forest were characterized by the predominance of foraging specialist species like grazers. However, as native vegetation is replaced by agriculture and urban areas, specialist species are replaced by species with generalist diet like detritivores. In streams surrounded by larger areas of agriculture, functional richness and divergence increased, while functional evenness decreased. Most likely, these changes were induced by alterations in the water quality, indicated by increased electrical conductivity and water temperature in streams with more agriculture areas. In conclusion, the conservation of the native forest vegetation is essential to maintain habitat characteristics and ecological processes in streams and to avoid the loss of specialist species in fish communities.