Simulating the reforestation of Polylepis australis mountain woodlands in the Quebrada del Condorito Nacional park (Sierras Grandes, Argentina).

JAN HANSPACH, HENRIK VON WEHRDEN, DANIEL RENISON, CARLA COUTIERS, PAULA MARCORA, ANA CINGOLANI, ISABELL HENSEN

Bayreuth, Germany

Conferencia; 39th annual conference of the Ecological Society of Germany, Austria and Switzerland; 2009

Universität Bayreuth

Polylepis australis is the dominant tree species in the mountain woodlands of Central Argentina. Centuries of logging, fire clearance and livestock grazing reduced the ecosystem to a few forest patches covering about 8% of the mountains. The Quebrada del Condorito National Park aims to conserve and restore these woodlands, which occur at all extremes of the climatic gradients and consist of a dynamic forest-grassland mosaic. Here, we propose a complete suchlike vegetation mosaic as the final stage of the model. In order to identify optimal reforestation sites we established a dispersal model based on current occurrences, information on species ecology and environmental conditions. Long term dispersal only occurs downstream along rivers, while most seeds are carried by wind only a few meters. Actual Polylepis distribution was obtained from a Landsat based vegetation map, and model parameterisation based on GIS derived datasets was aided by existing literature. In the future we also aim to incorporate expert opinion from surveys of scientists, policy makers and local herders. Regardless of different model specifications the reforestation of the National Park lasts more than 1000 years, yet based on dispersal speeds obtained in previous studies a complete reforestation may take much longer. Planting trees at a dozen sites or more may however halve this time frame; so far, 16000 saplings have been planted, and future efforts will focus on sites identified within the model.