IADIZA   20886
INSTITUTO ARGENTINO DE INVESTIGACIONES DE LAS ZONAS ARIDAS
Unidad Ejecutora - UE
artículos
Título:
The effects of land use on environmental features and functional organization of macroinvertebrate communities in Patagonia low order streams
Autor/es:
MISERENDINO, M. L.; MASI C.I.
Revista:
Ecological Indicators
Editorial:
ELSEVIER
Referencias:
Año: 2010
ISSN:
1470-160X
Resumen:
Benthic invertebrates, water quality variables, chlorophyll a and particulate organic matter (POM) were
studied in 18 sites of mountain streams in Patagonia (Argentina) subjected to six different land uses:
native forest, pine plantation, pasture, harvest forest, urban and reference urban. Three streams of each
land use were studied in March 2006. Macroinvertebrates were sampled in three riffles and three pools
(n = 108) and biomass of detrital fractions of POM were quantified. Overall benthic POM biomass was
higher at native and harvest forest than pastures, whereas fine fraction (FPOM) was higher in harvest
forest than in pastures. Regarding to autotrophic subsidies bryophytes were the only that changed
consistently among uses. These differences in energy resources were correlated with changes in
community attributes. Shredder richness was clearly higher at native and harvest forest than exotic pine
plantations, collector gatherers density was consistently high at harvest sites, and total density was
significantly higher at urban and harvest forest. Multidimensional scaling ordination based on
macroinvertebrate density data showed a clear separation of forested (either native or exotic species)
from riparian modified areas (pasture, urban and harvest sites). Environmental variables having
explanation power on macroinvertebrate assemblages were mostly related with: detritus availability
(wood and leaves biomass) and impairment (total phosphorous and % sand). These results confirm that
macroinvertebrate assemblage structure in Patagonian low order streams can be altered by land use
practices. Among guild structure measures, those indicators based on benthic community functional
attributes, shredders richness and collectors density, resulted good candidates to assess land use
impacts. On account of riparian corridor management may be critical to the distribution of benthic taxa,
the maintenance of good conditions of vegetation adjacent to rivers will enhance water quality and the
environment for highly endemic headwater communities of Patagonian streams.
higher at native and harvest forest than pastures, whereas fine fraction (FPOM) was higher in harvest
forest than in pastures. Regarding to autotrophic subsidies bryophytes were the only that changed
consistently among uses. These differences in energy resources were correlated with changes in
community attributes. Shredder richness was clearly higher at native and harvest forest than exotic pine
plantations, collector gatherers density was consistently high at harvest sites, and total density was
significantly higher at urban and harvest forest. Multidimensional scaling ordination based on
macroinvertebrate density data showed a clear separation of forested (either native or exotic species)
from riparian modified areas (pasture, urban and harvest sites). Environmental variables having
explanation power on macroinvertebrate assemblages were mostly related with: detritus availability
(wood and leaves biomass) and impairment (total phosphorous and % sand). These results confirm that
macroinvertebrate assemblage structure in Patagonian low order streams can be altered by land use
practices. Among guild structure measures, those indicators based on benthic community functional
attributes, shredders richness and collectors density, resulted good candidates to assess land use
impacts. On account of riparian corridor management may be critical to the distribution of benthic taxa,
the maintenance of good conditions of vegetation adjacent to rivers will enhance water quality and the
environment for highly endemic headwater communities of Patagonian streams.
studied in 18 sites of mountain streams in Patagonia (Argentina) subjected to six different land uses:
native forest, pine plantation, pasture, harvest forest, urban and reference urban. Three streams of each
land use were studied in March 2006. Macroinvertebrates were sampled in three riffles and three pools
(n = 108) and biomass of detrital fractions of POM were quantified. Overall benthic POM biomass was
higher at native and harvest forest than pastures, whereas fine fraction (FPOM) was higher in harvest
forest than in pastures. Regarding to autotrophic subsidies bryophytes were the only that changed
consistently among uses. These differences in energy resources were correlated with changes in
community attributes. Shredder richness was clearly higher at native and harvest forest than exotic pine
plantations, collector gatherers density was consistently high at harvest sites, and total density was
significantly higher at urban and harvest forest. Multidimensional scaling ordination based on
macroinvertebrate density data showed a clear separation of forested (either native or exotic species)
from riparian modified areas (pasture, urban and harvest sites). Environmental variables having
explanation power on macroinvertebrate assemblages were mostly related with: detritus availability
(wood and leaves biomass) and impairment (total phosphorous and % sand). These results confirm that
macroinvertebrate assemblage structure in Patagonian low order streams can be altered by land use
practices. Among guild structure measures, those indicators based on benthic community functional
attributes, shredders richness and collectors density, resulted good candidates to assess land use
impacts. On account of riparian corridor management may be critical to the distribution of benthic taxa,
the maintenance of good conditions of vegetation adjacent to rivers will enhance water quality and the
environment for highly endemic headwater communities of Patagonian streams.
higher at native and harvest forest than pastures, whereas fine fraction (FPOM) was higher in harvest
forest than in pastures. Regarding to autotrophic subsidies bryophytes were the only that changed
consistently among uses. These differences in energy resources were correlated with changes in
community attributes. Shredder richness was clearly higher at native and harvest forest than exotic pine
plantations, collector gatherers density was consistently high at harvest sites, and total density was
significantly higher at urban and harvest forest. Multidimensional scaling ordination based on
macroinvertebrate density data showed a clear separation of forested (either native or exotic species)
from riparian modified areas (pasture, urban and harvest sites). Environmental variables having
explanation power on macroinvertebrate assemblages were mostly related with: detritus availability
(wood and leaves biomass) and impairment (total phosphorous and % sand). These results confirm that
macroinvertebrate assemblage structure in Patagonian low order streams can be altered by land use
practices. Among guild structure measures, those indicators based on benthic community functional
attributes, shredders richness and collectors density, resulted good candidates to assess land use
impacts. On account of riparian corridor management may be critical to the distribution of benthic taxa,
the maintenance of good conditions of vegetation adjacent to rivers will enhance water quality and the
environment for highly endemic headwater communities of Patagonian streams.
a and particulate organic matter (POM) were
studied in 18 sites of mountain streams in Patagonia (Argentina) subjected to six different land uses:
native forest, pine plantation, pasture, harvest forest, urban and reference urban. Three streams of each
land use were studied in March 2006. Macroinvertebrates were sampled in three riffles and three pools
(n = 108) and biomass of detrital fractions of POM were quantified. Overall benthic POM biomass was
higher at native and harvest forest than pastures, whereas fine fraction (FPOM) was higher in harvest
forest than in pastures. Regarding to autotrophic subsidies bryophytes were the only that changed
consistently among uses. These differences in energy resources were correlated with changes in
community attributes. Shredder richness was clearly higher at native and harvest forest than exotic pine
plantations, collector gatherers density was consistently high at harvest sites, and total density was
significantly higher at urban and harvest forest. Multidimensional scaling ordination based on
macroinvertebrate density data showed a clear separation of forested (either native or exotic species)
from riparian modified areas (pasture, urban and harvest sites). Environmental variables having
explanation power on macroinvertebrate assemblages were mostly related with: detritus availability
(wood and leaves biomass) and impairment (total phosphorous and % sand). These results confirm that
macroinvertebrate assemblage structure in Patagonian low order streams can be altered by land use
practices. Among guild structure measures, those indicators based on benthic community functional
attributes, shredders richness and collectors density, resulted good candidates to assess land use
impacts. On account of riparian corridor management may be critical to the distribution of benthic taxa,
the maintenance of good conditions of vegetation adjacent to rivers will enhance water quality and the
environment for highly endemic headwater communities of Patagonian streams.
higher at native and harvest forest than pastures, whereas fine fraction (FPOM) was higher in harvest
forest than in pastures. Regarding to autotrophic subsidies bryophytes were the only that changed
consistently among uses. These differences in energy resources were correlated with changes in
community attributes. Shredder richness was clearly higher at native and harvest forest than exotic pine
plantations, collector gatherers density was consistently high at harvest sites, and total density was
significantly higher at urban and harvest forest. Multidimensional scaling ordination based on
macroinvertebrate density data showed a clear separation of forested (either native or exotic species)
from riparian modified areas (pasture, urban and harvest sites). Environmental variables having
explanation power on macroinvertebrate assemblages were mostly related with: detritus availability
(wood and leaves biomass) and impairment (total phosphorous and % sand). These results confirm that
macroinvertebrate assemblage structure in Patagonian low order streams can be altered by land use
practices. Among guild structure measures, those indicators based on benthic community functional
attributes, shredders richness and collectors density, resulted good candidates to assess land use
impacts. On account of riparian corridor management may be critical to the distribution of benthic taxa,
the maintenance of good conditions of vegetation adjacent to rivers will enhance water quality and the
environment for highly endemic headwater communities of Patagonian streams.
n = 108) and biomass of detrital fractions of POM were quantified. Overall benthic POM biomass was
higher at native and harvest forest than pastures, whereas fine fraction (FPOM) was higher in harvest
forest than in pastures. Regarding to autotrophic subsidies bryophytes were the only that changed
consistently among uses. These differences in energy resources were correlated with changes in
community attributes. Shredder richness was clearly higher at native and harvest forest than exotic pine
plantations, collector gatherers density was consistently high at harvest sites, and total density was
significantly higher at urban and harvest forest. Multidimensional scaling ordination based on
macroinvertebrate density data showed a clear separation of forested (either native or exotic species)
from riparian modified areas (pasture, urban and harvest sites). Environmental variables having
explanation power on macroinvertebrate assemblages were mostly related with: detritus availability
(wood and leaves biomass) and impairment (total phosphorous and % sand). These results confirm that
macroinvertebrate assemblage structure in Patagonian low order streams can be altered by land use
practices. Among guild structure measures, those indicators based on benthic community functional
attributes, shredders richness and collectors density, resulted good candidates to assess land use
impacts. On account of riparian corridor management may be critical to the distribution of benthic taxa,
the maintenance of good conditions of vegetation adjacent to rivers will enhance water quality and the
environment for highly endemic headwater communities of Patagonian streams.