احمد ولی پور

The main job of rural community in the northern Zagros forests especially in Baneh (study area) is animal husbandry. In order to natural difficulties and lack of rangeland, local people have innovated pollarding (in local term is called Glazani). In this traditional forest management system, each rural family conventionally owns an area of the forest (in local term is called Gala-jar) which divides into three or four parts (the local term for each part is Shane-Gala). Each year a part is used to collect tree leaves through pollarding to provide winter fodder for livestock. This study was conducted in Baneh forests to determine allometric equations of forage production of Lebanon oak trees in traditionally managed forest stands. Five stands (Glajar) were subjected to the randomized-systematic sampling and then the following characteristics of trees were measured in 33 circular sample plots (1000 m2): diameter at breast height (dbh), collar diameter, tree height, crown height and perpendicular diameters of crown. In the Glazani season (early September), 101 trees (Q. libani) which classified in 9 dbh classes (dbh from 5 to 50 cm) and three crown height classes (upper, middle, and lower crown) was subjected to Glazani operation. The wet weight of tree forage was measured in field. Some subsamples were dried in oven for 48 hours at 80˚c to calculate the dry weight of leafs and branches. To develop a regression model for estimating tree forage, the measured Biometric indices considered as independent variables in multivariate regression models. The statistical parameters such as R2, standard deviation of the model, analysis of variance, mean square error, and t test of regression coefficient was calculated and used for evaluating and choosing the best model. The results showed that the best regression model for estimating tree forage (dry leaf biomass) was a power model ( ) in which the dbh was the independent variable and calculated R2 was 0.82, 0.77, 0.63, and 0.82 res