INVESTIGADORES
DIAZ VILLANUEVA veronica
capítulos de libros
Título:
Leaf litter dynamics in a forested small Andean catchment, northern Patagonia, Argentina
Autor/es:
ALBARIÑO, RICARDO; DÍAZ VILLANUEVA, VERÓNICA; BURIA, LEONARDO
Libro:
Ecological advances on Chilean temperate rainforests
Editorial:
Academia Press
Referencias:
Año: 2009; p. 183 - 211
Resumen:
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Abstract. This study
describes structural and functional aspects associated with detritus dynamics
in a Nothofagus pumilio forest small watershed that is located in the
driest extreme of the eastwardly pluvial gradient in northern Patagonia.
During the study the bulk of
organic matter fell between late-summer and late-autumn (stream inputs of
deciduous Nothofagus leaves collected in a neighbor stream = 97-111 g AFDM m-2).
Leaf litter retained in the stream bottom was higher in autumn and winter (5-30 g DM m-2) and
was dominated year round by Nothofagus pumilio (lenga). Detritus
accumulations had 5 to 26 times more lenga leaves than those of other species.
In the water year 2006, leaf litter shed at the driest period was redistributed
along headwater extensions during the first spate (May 2006). In this event, a
substantial amount of lenga leaves were exported from the upper catchment and
travelled more than 9 km
downstream. The average of our estimated k values (0.0067 ± 0.0017, mean
± 1 s.e.) was at the lower limit of the intermediate decay rate category.
Although lenga leaves seem to be of poor food quality and they dominate the
benthic detrital food base in headwater streams most of the time, the community
structure was dominated by detritivores (~75%) both in biomass and density with
shredders representing ~50% of total biomass year round and collectors with
~50% of community density. Waterfalls act as natural physical barriers preventing
the upstream settlement of the exotic rainbow trout and, in doing so, allow
pristine functional and structural conditions to occur as in pre-trout
introduction times.