INVESTIGADORES
MARTINEZ PASTUR Guillermo Jose
congresos y reuniones científicas
Título:
Variable retention as a strategy to protect insect diversity in managed South Patagonian forests
Autor/es:
MV LENCINAS; G MARTÍNEZ PASTUR
Lugar:
CANADA
Reunión:
Congreso; 24 INTERNATIONAL CONGRESS FOR CONSERVATION BIOLOGY; 2010
Resumen:
Traditional silviculture affects insect diversity of old-growth forests. Over the last decade,
however, variable retention has been proposed as a strategy to mitigate species losses. We
compared insect diversity in Nothofagus pumilio forests managed with variable retention and
traditional forestry during the first four years after harvesting. Adult insects were sampled
through a wide spectrum traps (pit-fall, alcohol, lights and color trays) set in managed
(aggregated retention, variable retention and dispersed retention) and unmanaged stands.
Richness and relative abundance were analyzed with classification and ordination using NMS,
PERMANOVA and PERMDISP. A total of 282 morphospecies were identified, mainly in the
orders Diptera, Coleoptera, Lepidoptera and Hymenoptera. Richness and relative abundance
trend to decrease in harvested forests compared to the unmanaged ones, depending on the level
of habitat damage and time after harvesting. Multivariate analyses showed similarities between
unmanaged stands and aggregated retention areas, however, great dissimilarities were observed
among the years. Introduced species from other environments were higher in harvested than in
retained areas. Variable retention conserved insect diversity better than aggregated retention or
traditional forestry (dispersed retention or clear-cuts) by maintaining old-growth forest diversity
inside the aggregates and decreasing the impact of forestry in the harvested areas.