version ISSN 1667-782X
TORRELA, Sebastián A et al. Structure, composition and state of conservation of the woody-plant community of the "tres quebrachos" forests in the Subhumid Central Chaco. Ecol. austral [online]. 2011, vol.21, n.2, pp. 179-188. ISSN 1667-782X.
The "tres quebrachos" forests in the SW Province of Chaco was scantily studied and strongly affected by the advance of the agricultural frontier. We studied the composition, structure and state of conservation of the woody plant community in remnants fragments. We determined the species richness and the community composition, and basal area and density of each woody species sampling 60 plots distributed in 16 forest fragments (between 5 and >1000 ha). We detected 36 species (trees and shrubs), all of them native. Considering all species together, the mean basal area for all sites was of 24.73 m2/ha, and the density of 13459 individuals/ha. We found a codominance between Schinopsis balansae and Aspidosperma quebracho-blanco among the species of the upper strata. The stump's analysis showed that selective extraction is limited and it does not imply a strong alteration of the forest structure. To assess the conservation status of these forests, results were compared with published data for other quebracho forests of protected areas from other subregions of the Argentine Chaco. We found a remarkable similarity in the richness and structural parameters of the community. Considering the severe fragmentation of "tres quebrachos" forests, our results reflect a surprisingly satisfactory state of conservation. It is necessary to design and implement management strategies to ensure the conservation of this environment.
Keywords : Chaco Forest; Schinopsis; Plant diversity; Conservation in agricultural landscapes.