Estimation of leaf area index and assessment of its allometric equations in oak forests: Northern Zagros, Iran

The focus of the present study is the estimation of leaf area index (LAI) and the assessment of allometric equations for predicting the leaf area of Lebanon oaks (Quercus libani Oliv.) in Iran’s northern Zagros forests. To that end, 50 oak trees were randomly selected and their biophysical parameters were measured. Then, on the basis of destructive sampling of the oak trees, their specific leaf area (SLA) and leaf area were measured. The results showed that SLA and LAI of the Lebanon oaks were 136.9 cm·g–1 and 1.99, respectively. Among all the parameters we measured, the crown volume exhibited the highest correlation with LAI (r2 = 0.65). The easily measured tree parameters such as diameter at breast height did not show a high correlation with leaf area (r2 = 0.36). Our obtained moderate correlations in the allometric equations could be due to the fact that branches of these trees had been pollarded by the local people when the branches were only 3 or 4 years old; therefore, the natural structure of the crowns in these trees might have been damaged.