Structure, biomass, and secondary production of benthic macroinvertebrates in subtropical Andean rivers

HANKEL, GUILLERMO; NIETO, CAROLINA; ROMERO, FÁTIMA; GULTEMIRIAM, LOURDES; REYNAGA, MARÍA CELINA; TABOADA, MARÍA; RUEDA MARTÍN, PAOLA; RODRÍGUEZ, JOSÉ SEBASTIÁN; MANZO, VERÓNICA; MOLINERI, CARLOS

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Lugar: Rio de Janeiro; Año: 2023

0001-3765

Secondary production, the formation of heterotrophic biomassacross time, integrates several important ecological processes that affect the lifeof organisms, populations, communities and ecosystems, but its study has not receivedmuch attention in South America. The objectives of this work were to describethe diversity of benthic macroinvertebrate assemblages in terms of abundanceand biomass, and to quantify their secondary production for the first time inAndean rivers. A quantitative sampling scheme was implemented, using a Surbersampler, in three forested streams. Physical-chemical variables, nutrients,organic matter and chlorophyll were measured also. The macroinvertebrates wereseparated and identified mostly to species level. Each taxon was assigned to afunctional feeding group. Secondary production was estimated for taxa, mostlyDiptera, Trichoptera, Coleoptera and Ephemeroptera. The annual production variedfrom 3769 to 13916 mg dry mass m-2 y-1. Most abundant taxa were also those withhigher production, dominated by Ephemeroptera (Baetidae), Trichoptera (Hydropsychidae)and Diptera (Chironomidae and Simuliidae). Density, biomass and production ofcollectors and predators were much higher than the other feeding groups. Weexpect that our results will be useful to evaluate the effects on streamfunctioning produced by global warming and other anthropogenic disturbances inour region.