IMASL   20939
INSTITUTO DE MATEMATICA APLICADA DE SAN LUIS "PROF. EZIO MARCHI"
Unidad Ejecutora - UE
artículos
Título:
An exploration of direct and indirect drivers of herbivore reproductive performance in arid and semi arid rangelands by means of structural equation models
Autor/es:
TEXEIRA, MARCOS A.; BALDI, GERMÁN; PARUELO, JOSÉ M.
Revista:
JOURNAL OF ARID ENVIRONMENTS
Editorial:
ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD
Referencias:
Año: 2012 vol. 81 p. 26 - 34
ISSN:
0140-1963
Resumen:
Climate variability affects both animal and plant populations. Understanding how this variability ismodulated by topography, vegetation and population densities and how this impact on ungulatedemography is an important step in order to forecast consequences of alternative management scenariosor the effects of climate change.Structural equation modeling (SEMs) is a tool particularly suited to this kind of situations, and allowedus to study the direct and indirect effects of climate, topography, structural and functional aspects ofvegetation and population density upon reproductive performance of Patagonian sheep flocks, measuredat paddock scale. The application of SEMs in conjunction with information criteria and related techniquesfor model selection, model averaging and multi-model inference revealed that despite considerablemodel uncertainty, those paddocks towards the East, with a greater spatial variability in July temperaturesand greater primary production during fall-winter (estimated by remote sensing) showed greaterlambing rates. Paddocks with higher proportion of meadows and with more intense forage consumption,were also associated with a better reproductive performance. Our results not only provide quantitativehypothesis about the controls at the landscape level of herbivore performance but also provide the basisto devise better management alternatives.