Effects of anthropogenic habitat disturbance on local pollinator diversity and species turnover across a precipitation gradient

QUINTERO CAROLINA; MORALES CAROLINA LAURA; AIZEN MARCELO ADRIAN

BIODIVERSITY AND CONSERVATION

SPRINGER

Año: 2010 vol. 19 p. 257 - 274

0960-3115

Anthropogenic habitat disturbance can have profound effects on multiple components of forest biotas including pollinator assemblages. We assessed the effect of small-scale disturbance on local richness, abundance, diversity and evenness of insect pollinator fauna; and how habitat disturbance affected species turnover across the landscape and overall diversity along a precipitation gradient in NW Patagonia (Argentina). We evaluated the effect of disturbance on overall pollinator fauna and then separately for bees (i.e. Apoidea) and non-bee pollinators. Locally, disturbed habitats had significantly higher pollinator species richness and abundances than undisturbed habitats for the whole pollinator assemblage, but not for bees or non-bees separately. However, significant differences in species richness between habitats vanished after accounting for differences in abundance between habitat types. At a local scale Shannon–Weaver diversity and evenness did not vary with disturbance. A b diversity index indicated that, across forest types, species turnover was lower between disturbed habitats than between undisturbed habitats. In addition, rarefaction curves showed that disturbed habitats as a whole accumulated fewer species than undisturbed habitats at equivalent sample sizes. We concluded that small patches of disturbed habitat have a negligible effect on local pollinator diversity; however, habitat disturbance reduced b diversity through a homogenization of the pollinator fauna (in particular of bees) across the landscape. fauna (in particular of bees) across the landscape. species turnover was lower between disturbed habitats than between undisturbed habitats. In addition, rarefaction curves showed that disturbed habitats as a whole accumulated fewer species than undisturbed habitats at equivalent sample sizes. We concluded that small patches of disturbed habitat have a negligible effect on local pollinator diversity; however, habitat disturbance reduced b diversity through a homogenization of the pollinator fauna (in particular of bees) across the landscape. fauna (in particular of bees) across the landscape. b diversity index indicated that, across forest types, species turnover was lower between disturbed habitats than between undisturbed habitats. In addition, rarefaction curves showed that disturbed habitats as a whole accumulated fewer species than undisturbed habitats at equivalent sample sizes. We concluded that small patches of disturbed habitat have a negligible effect on local pollinator diversity; however, habitat disturbance reduced b diversity through a homogenization of the pollinator fauna (in particular of bees) across the landscape. fauna (in particular of bees) across the landscape. b diversity through a homogenization of the pollinator fauna (in particular of bees) across the landscape.