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چکیده
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In the northern Zagros, western Iran, each rural household customarily owns an area (≤ 40 ha) of forest. A stand owner divides it into three sections and pollarding is performed in one section annually on a three-year rotation. The leafy branches of pollarded trees are stored on “store” trees in forest. This research attempts to quantitatively describe the pollarding process. In three representative stands an inventory of all trees (DBH ≥ 5 cm) in the pollarded section was conducted: DBH, total height, trunk height and crown diameters were measured. At the time of pollarding, 10% of the foliage stacks were randomly selected and weighed. The positions of each store tree and horizontal distance of pollarded trees associated with each store tree was recorded. The results indicated that the number and weight of foliage stacks resulting from pollarding of each tree correlated (0.48 and 0.43, respectively) with their crown diameter. The average dry weight of leaf biomass was 1,525.6 ±108.1 kg/ha and there was a significant difference between the selected stands. The average pollarded area and the average number of trees in the pollarded area of each store tree was 501.1±210.4 m2 and 9.4±3.5 trees, respectively. The number of pollarded trees associated with each store tree and the weight of stored foliage stacks on them are determined by the distance between pollarded trees and store trees, the number of trees around the store trees and the ability of selected store trees to bear the weight of foliage stacks.
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