Abstract

Nothofagus pumilio and N. betuloides, forest species of Southern Patagonia, can appear as pure stands or in mixed forests patches, in patterns that are greatly influenced by dominant pedogenetic processes of each species. The aim of this study was to evaluate chemical and physical properties of soils and relationships between pure forests N. pumilio (Np), N. betuloides (Nb) and mixed forests (M) in coastal and mountain landscapes in Tierra del Fuego. Sixty soil samples were taken at 10 cm depth (30 samples for each landscape and forest type). Chemical properties included nutrient content (%, ratio, C, N and P), organic matter, pH and cation exchange capacity (CEC), and physical properties, such as soil compaction, texture, apparent density, temperature and moisture, were measured as well. Using ANOVA and multivariate analysis, we found no difference between forest soil chemistry by forest type. However, significant differences were found when comparing samples by landscape. P% was higher in coastal sites and significantly higher (p=0.05) in pure Np stands. C/N ratio was greater in coastal forests while pH and CEC were higher in mountain sites. Organic matter content was statistically similar at forest and landscape levels. Significant differences in physical properties between the coastal and mountain sites were also detected. Mountain sites have a high percentage of sand, with greater CEC, apparent density and soil moisture. In contrast, soil composition in coastal sites was silty-clay with a high resistance to compaction. It is concluded that soil physical and chemical properties vary significantly between landscapes, and the ecological implications of this finding could be influential in the management of ecosystems.