The influence of soil type, slope and drainage on tree growth patterns (density, tree size, crown canopy cover and cork yield) was assessed in acork oak montado, located in Central-western Portugal, based on a GIS approach followed by field survey. Five soil groups, that is, Arenosols,Regosols, Podzols, Luvisols and Gleysols, combined in three slope classes (flat, undulating and steep) under two different hydromorphic conditions(normal or deficient) were compared based on five cork oak stand parameters using ANOVA and PCA tests. The results showed a clear influence ofsoil type on cork oak growth patterns (cork yield, basal area, number of trees per hectare, crown canopy cover and circumference at breast height).In Arenosols all parameters showed maximum values and, in contrast, in Gleysols were found the minimum values. For instance, the average ofthe annual cork production for Gleysols (153 kg ha 1 year 1) was only 70% of the expected annual cork production of Arenosols(219 kg ha 1 year 1) and the average exploited tree density decreased from 56 trees ha 1 in Arenosols to 44 trees ha 1 in Gleysols, for anaverage exploited tree density of 53 trees ha 1 for the study area. Slope also seems to influence the cork oak growth patterns, as significantstatistical differences were found for cork oak growth parameters between slope classes: steep slopes decreased the cork production, the tree size(circumference at breast height) and the tree density. An overall PCA test showed that three main soil groups could be identified: (i) Arenosols andPodzols; (ii) Regosols and (iii) Luvisols and Gleysols, showing that the former, which could allow the tree root development, have a positiveinfluence on the cork oak growth. A two-way analysis of variance, for soil type and slope, showed that the cork yield and the exploited tree densityare clearly affected by these two factors interaction.
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