CONICET | Buscador de Institutos y Recursos Humanos

The Argentinean Arid Chaco in the last 150 years had simultaneously suffered two highly transformative processes: a reduction in the native forests area to incorporate new agricultural lands and an increase in the area of implanted pastures for livestock over natural grasslands. Arbuscular Mycorrhizal Fungi (AMF) are obligate symbionts of the 80% of the terrestrial plants and improve their ability to acquire nutrients, mainly Phosphorus. In general AMF abundance and effectiveness with respect to root colonization and plant growth promotion are declining upon agricultural intensification. However, little is known about the effect of management practices on the species diversity and community structure of AMF. Our objective was to analize the HMA diversity changes in the different management and land use units, considering the Native Forest as the pristine situation and along a gradient of diverse land uses units, to determinate which species are favored, and those that are disadvantages against the management and land uses changes. The following land use systems were selected: Native forest, Shrublands, Nopals Agriculture, Fruit trees, Fallow lands, Alfalfa meadows and Implanted grasslands. AMF spores were counted and identified both for samples taken directly from field sites. Preliminary results indicate that Annual Crops and Pastures are more diverse than Native forests and that this diversity would seem to be related to the intensity of use and management.Acknowledges: L. Risio and E. Ontivero are postdoctoral and doctoral fellows respectively, the field work was financied by FonCyT (ANPCyT) project: ?Análisis de la relación entre usos de la tierra, biodiversidad y servicios ecosistémicos: selección de indicadores para un ordenamiento territorial sustentable en el noroeste de la provincia de Córdoba? (BID PICT PRH 108).The Argentinean Arid Chaco in the last 150 years had simultaneously suffered two highly transformative processes: a reduction in the native forests area to incorporate new agricultural lands and an increase in the area of implanted pastures for livestock over natural grasslands. Arbuscular Mycorrhizal Fungi (AMF) are obligate symbionts of the 80% of the terrestrial plants and improve their ability to acquire nutrients, mainly Phosphorus. In general AMF abundance and effectiveness with respect to root colonization and plant growth promotion are declining upon agricultural intensification. However, little is known about the effect of management practices on the species diversity and community structure of AMF. Our objective was to analize the HMA diversity changes in the different management and land use units, considering the Native Forest as the pristine situation and along a gradient of diverse land uses units, to determinate which species are favored, and those that are disadvantages against the management and land uses changes. The following land use systems were selected: Native forest, Shrublands, Nopals Agriculture, Fruit trees, Fallow lands, Alfalfa meadows and Implanted grasslands. AMF spores were counted and identified both for samples taken directly from field sites. Preliminary results indicate that Annual Crops and Pastures are more diverse than Native forests and that this diversity would seem to be related to the intensity of use and management.Acknowledges: L. Risio and E. Ontivero are postdoctoral and doctoral fellows respectively, the field work was financied by FonCyT (ANPCyT) project: ?Análisis de la relación entre usos de la tierra, biodiversidad y servicios ecosistémicos: selección de indicadores para un ordenamiento territorial sustentable en el noroeste de la provincia de Córdoba? (BID PICT PRH 108).