Evaluation of Tree Marking in Persian Ironwood-hornbeam Stands at Bahramnia Forestry Plan and Its Effect on Stand Structure
نویسندگان
چکیده مقاله:
Tree marking can cause changes in forest. This study aimed to assess tree marking operation and to predict its effect on stand structure of Persian ironwood-hornbeam stands at Bahramnia forestry plan, north of Iran. Therefore 98 trees that were marked in compartment 9 of the mentioned forest in 2017 based on selection system and according to the recent laws of Forests, Range and Watershed Management Organization of Iran were measured before cut. Characteristics such as tree species, diameter, height, volume, decay condition and standing or fallen situation of the trees were recorded. Independent samples t-test was used to compare the mean diameter, height and volume between marked trees and stand trees. To obtain the mean diameter and height of the stand trees 16 circular sample plots with the area of 1000 square meters were considered in which the diameter and height of all trees were recorded. The results showed that the majority of marked trees, based on both tree numbers and volume, belong to hornbeam species while the dominant tree species of the compartment is Persian ironwood tree. This result shows that the marking operation acted to change the species composition of the stand in favor of Persian ironwood species. In comparison of the mean diameter, height and volume between marked trees with stand trees a significant difference were observed in terms of diameter and volume, but in case of trees height no significant difference was found. Studying the distribution pattern of marked trees indicated a cluster distribution pattern. Totally it can be concluded that tree marking operation according to the recent laws of Forests, Range and Watershed Management Organization, which emphasize on marking and cutting of fallen and broken and decaying trees, in long term will result in loss of dead and decaying trees in forest ecosystem and will decrease ecological capacity of these forest ecosystems.
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عنوان ژورنال
دوره 7 شماره None
صفحات 111- 123
تاریخ انتشار 2019-12
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