INVESTIGADORES
GIORGIS Melisa Adriana
artículos
Título:
Direct and indirect effects of climate on decomposition in native ecosystems from central Argentina
Autor/es:
. PÉREZ HARGUINDEGUY N, DÍAZ S, VENDRAMINI F, GURVICH D E, CINGOLANI A M, GIORGIS M A & CABIDO M.
Revista:
AUSTRAL ECOLOGY
Editorial:
WILEY-BLACKWELL PUBLISHING, INC
Referencias:
Año: 2007 vol. 32 p. 749 - 757
ISSN:
1442-9985
Resumen:
Climate affects litter decomposition directly through temperature and moisture, determining the
ecosystem potential decomposition, and indirectly through its effect on plant community composition and litter
quality, determining litter potential decomposition. It would be expected that both the direct and indirect effects
of climate on decomposition act in the same direction along gradients of actual evapotranspiration (AET).
However, studies from semiarid ecosystems challenge this idea, suggesting that the climatic conditions that favour
decomposition activity, and the consequent ecosystem potential decomposition, do not necessarily lead to litter
being easier to decompose.We explored the decomposition patterns of four arid to subhumid native ecosystems
with different AET in central-western Argentina and we analysed if ecosystem potential decomposition (climatic
direct effect), nutrient availability and leaf litter potential decomposition (climatic indirect effect) all increased with
AET. In general, the direct effect of climate (AET) on decomposition (i.e. ecosystem potential decomposition),
showed a similar pattern to nutrient availability in soils (higher for xerophytic and mountain woodlands and lower
for the other ecosystems), but different from the pattern of leaf litter potential decomposition. However, the range
of variation in the ecosystem potential decomposition was much higher than the range of variation in litter potential
decomposition, indicating that the direct effect of climate on decomposition was far stronger than the indirect effect
through litter quality. Our results provide additional experimental evidence supporting the direct control of climate
over decomposition, and therefore nutrient cycling. For the ecosystems considered, those with the highest AET are
the ecosystems with the highest potential decomposition. But what is more interesting is that our results suggest that
the indirect control of climate over decomposition through vegetation characteristics and decomposability does not
follow the same trend as the direct effect of climate.This finding has important implications in the prediction of the
effects of climate change on semiarid ecosystems.