INVESTIGADORES
LEGGIERI Leonardo RamÓn
artículos
Título:
Effects of macrophyte heterogeneity and food availability on structural parameters of the macroinvertebrate community in a Pampean stream
Autor/es:
FERREIRO NICOLÁS ANDRÉS; FEIJOÓ CLAUDIA SILVINA; GIORGI ADONIS DAVID NAZARENO; LEGGIERI LEONARDO RAMÓN
Revista:
HYDROBIOLOGIA
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2011 vol. 664 p. 199 - 211
ISSN:
0018-8158
Resumen:
Environmental
heterogeneity in natural ecosystems influences several parameters at the
population and community levels. In freshwater ecosystems, habitat
heterogeneity can be provided by macrophyte species with different structural
shapes. Previous studies suggest that aquatic plants with more complex
architectures will support higher number, biomass, and taxon richness of
macroinvertebrates than plants with simpler shape. We investigated the influence
of macrophyte structural heterogeneity (quantified by fractal dimension) and
food availability (represented by epiphytic biomass) on several parameters
(number of individuals, biomass, body size distribution, taxon richness, and
diversity) of the macroinvertebrate community in a Pampean stream. Four
submerged macrophyte species (Egeria densa, Elodea ernstae, Ceratophyllum demersum, and Stuckenia striata) and associated macroinvertebrates were
sampled in late spring, summer, and autumn. Plants were photographed and
fractal dimension was estimated from the images by the box-counting method.
Fractal dimension was independent of plant surface area per unit of macrophyte
biomass and differed significantly among species. Mean fractal dimension varied
between 1.29 and 1.62, and increased following the sequence E. densa -> S. striata -> E. ernstae -> C. demersum. Macrophyte species with higher fractal
dimension supported a greater abundance of macroinvertebrates, especially those
of small body size (500?1,000 microm); but fractal dimension
was unrelated to macroinvertebrate biomass, richness, and diversity. However,
overall animal biomass was significantly associated to the epiphytic abundance.
Consequently, macrophyte heterogeneity influences macroinvertebrate density and
body size distribution, while animal biomass depends on epiphytic food
resources provided by plants.