CONICET | Buscador de Institutos y Recursos Humanos

The driest part of the Argentinean pampasis occupied by semiarid woodlands dominates by Prosopis caldenia Burkart(Calden). Calden pods are a highly valuable fodder supplement for livestock butits production is highly variable. Our objective was to analyze and model thetemporal pattern in inter-annual variability of Calden pod production. Our keyhypothesis is that weather conditions are the main determinant of the podmasting behaviour. Tree size and climatic variables were evaluated as explanatorycovariates using a zero-inﬂated log-normal modelling approach. The proposedﬁnal model structure incorporated 25 parameters, including four variancecomponents, two intercepts for both the logistic and the log-normal parts ofthe model, and nineteen parameters associated with ﬁxed effects.Climate had astrong inﬂuence on the ﬂowering-fruiting Calden process and on the inter-annualvariability of the ﬁnal pod production at the tree level. Temperatures duringbud breaking, ﬂowering and fruit shedding, together with the precipitation fromthe ﬁnal month of fruit shedding and the total amount of the prior vegetativecycle, were the main weather covariates that affect the processes.