INVESTIGADORES
DIAZ VILLANUEVA veronica
artículos
Título:
Detritivores feeding on poor quality food are more sensitive to increased temperatures
Autor/es:
DÍAZ VILLANUEVA, VERÓNICA; ALBARIÑO, RICARDO; CANHOTO, CRISTINA
Revista:
HYDROBIOLOGIA
Editorial:
SPRINGER
Referencias:
Año: 2011 vol. 678 p. 155 - 165
ISSN:
0018-8158
Resumen:
As temperature increases the metabolic rates, the effect of warming on animals will also enhance animal-driven nutrient cycling with important consequences on ecosystem dynamics. We tested the effects of increased temperature (15 and 20_C, optimal and suboptimal temperatures, respectively) on metabolic rates of the shredder larvae Sericostoma vittatum fed on three diets, Alnus glutinosa (L.) Gaertn., Eucalyptus globulus Labill. and Quercus robur L. We measured P and N content in leaves, faeces and excreta and calculated C, N, and P assimilation efficiencies, and mass balances. Carbon assimilation efficiency (AE) was reduced at 20_C when larvae fed on Q. robur; nitrogen-AE was reduced at 20_C in all diets and phosphorus-AE was not affected by temperature. Larvae achieved a net N gain in all treatments, however, increased temperatures had a negative effect on N incorporation into body tissue. The mass balance of P was negatively affected by temperature; larvae fed on Q. robur and on E. globulus had null balances at 15_C and negative at 20_C. Our results showed that high temperature increased nutrient excretion and affected N:P ratios in excreta, thus changes in temperature may have severe consequences on larval mediated leaf litter processing and nutrient cycling. However, the type of diet seemed to modulate the way temperature affects larval metabolism regarding excretion rate and assimilation efficiencies. The extent to which optimal– suboptimal temperature variation will alter detritivore metabolism performance, internal nutrient balance and hence, cycling of elements in the environment seems crucial under global warming scenarios.