Human land-use intensification threatens stream biodiversity and
ecosystem functioning
Abstract
Human land-use is changing Earth’s surface, causing a decline in
biodiversity and altering ecosystem functioning. However, most of the
empirical evidence of land-use impacts in the Neotropics comes from
studies investigating isolated land-use types, and the pathways by which
intensified land-uses affect ecosystem functioning are largely unknown.
Using a database from 61 streams spanning two hyperdiverse Neotropical
regions, we demonstrate that intensive human land-uses (agriculture,
urbanization, pasture, and afforestation) strongly affect stream
biodiversity and functioning. We showed negative associations of
agriculture, pasture and urbanization with taxonomic richness,
functional diversity, and diversity of trait categories (recruitment and
life-history, resource and habitat-use, and body size) of fish,
arthropod, and macrophyte. The impacts of intensive land-uses on
standing biomass were negative and driven by direct and indirect effects
mediated by declines in taxonomic and functional diversities. Our
findings highlight that human land use can reshape stream biodiversity,
with multiple negative consequences on ecosystem functioning.