Anthropogenic disturbance impact on the stem growth of Prosopis flexuosa DC forests in the Monte desert of Argentina: A dendroecological approach

SERGIO PIRAINO; ELENA MARÍA ABRAHAM; MARTÍN ARIEL HADAD; DANIEL PATON; FIDEL ALEJANDRO ROIG

Dendrochronologia

ELSEVIER GMBH, URBAN & FISCHER VERLAG

Lugar: ALEMANIA; Año: 2017 p. 63 - 72

1125-7865

Anthropogenic disturbance acts globally as an ecological process with long-term implication on theecosystem equilibrium. In the central-western Argentina (Desierto del Monte Central: DMC), the desertProsopis flexuosa woodlands has been intervened by man with differential incidence, e.g. through log-ging, fire and grazing. Despite recognizing a history of disturbances in these forests, the local removal oftrees and its incidence in the stem growth of the surviving trees is still poorly known. Dendroecologicalmethods were applied to 10 plots distributed along a landform gradient, aiming to analyze how distur-bance, together with possible modulation effects of the spatial variability on growth, can influence forestdynamics. Tree removal was an intensive practice during the second half of the 20th century in the DCM,in synchrony with the expansion of wine-growing activity. Our results suggest that removal of P. flexuosaindividuals in any considered plot was the main driver of changes in the forest dynamics. This argumentis based on the weak climatic incidence in years considered critical with respect to the beginning ofabrupt tree-growth releases. This disturbance impact seemed to be landform-dependent, as suggestedby the higher relative basal area values at mesic sites in relation to sites linked to drier landforms. Thepresented findings represent the first attempt in reconstructing the disturbance regime experienced bythe DMC P. flexuosa woodlands. Our research contributes to interpret how logging practices coupled withlandform-related heterogeneities may influence the forest dynamics at desert environments, providingelements for implementing policies for conservation and management of these natural resources.