Body size has primacy over stoichiometric variables in nutrient excretion by a tropical stream fish community.
Sci Rep
; 12(1): 14844, 2022 09 01.
Article
en En
| MEDLINE
| ID: mdl-36050417
ABSTRACT
Ecological Stoichiometry (ES) and the Metabolic Theory of Ecology (MTE) are the main theories used to explain consumers' nutrient recycling. ES posits that imbalances between an animal's body and its diet stoichiometry determine its nutrient excretion rates, whereas the MTE predicts that excretion reflects metabolic activity arising from body size and temperature. We measured nitrogen, phosphorus and NP excretion, body NP stoichiometry, body size, and temperature for 12 fish species from a Brazilian stream. We fitted competing models reflecting different combinations of ES (body NP, armor classification, diet group) and MTE (body size, temperature) variables. Only body size predicted P excretion rates, while N excretion was predicted by body size and time of day. NP excretion was not explained by any variable. There was no interspecific difference in size-scaling coefficients neither for N nor for P. Fitted size scaling coefficients were lower than the MTE prediction of 0.75 for N (0.58), and for P (0.56). We conclude that differences in nutrient excretion among species within a shared environment primarily reflect contrasts in metabolic rates arising from body size, rather than disparities between consumer and resource stoichiometry. Our findings support the MTE as the primary framework for predicting nutrient excretion rates.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Ecosistema
/
Ríos
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Sci Rep
Año:
2022
Tipo del documento:
Article
País de afiliación:
Brasil