Characterization of Nothofagus pumilio (lenga) understory in managed and unmanaged forests of central Patagonia, Argentina

SILVA, P.V.; BAVA, J.O.; QUINTEROS, CP; DEFOSSÉ, G.E.; GRESLEBIN A.G.; SILVA, P.V.; BAVA, J.O.; QUINTEROS, CP; DEFOSSÉ, G.E.; GRESLEBIN A.G.

FOREST SCIENCE

SOC AMER FORESTERS

Año: 2017 vol. 63 p. 173 - 183

0015-749X

In managed forests, biodiversity conservation is crucial for the sustainable use of ecosystem resources. In the Patagonian-Andes forests of Argentina, lenga (Nothofagus pumilio) is the most important native tree because of its ecological functions and economic importance as a timber provider. In this study, we determined how the shelterwood-cut system impacts understory vegetation attributes in three sites representing typical lenga forests of central Andean-Patagonia. In each site, two 250-m2 treatment plots (managed and unmanaged) were established, and canopy cover, soil temperature, and moisture were determined. Within plots in 10 randomly placed 0.25-m2 microplots, we determined plant cover, from which we calculated diversity attributes. Canopy cover and soil moisture were higher in unmanaged treatments, whereas the reverse was true for soil temperature. The Shannon-Wiener index showed similar values (∼1), whereas species richness was slightly higher in unmanaged (4.8 ± 0.5) than in managed treatments (3.8 ± 0.3). Generally, native plants dominated the understory (∼40٪), whereas exotic species were rare (∼1٪). Shrub cover was higher in managed (24.1 ± 4.2) than in unmanaged (9.5 ± 1.7) treatments, whereas herbaceous species dominated unmanaged forests. These results confirm that the shelterwood-cut system may be used for diversity conservation in Patagonian lenga forests.