نوع مقاله : علمی - پژوهشی
نویسندگان
1 دانشجوی دکترای جنگلداری، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران
2 استاد گروه جنگلداری، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران
3 دانشیار گروه جنگلداری، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Decline of trees in arid and semi-arid regions of Zagros has been considered as one of the main problems of ecosystems that affects the spatial patterns of trees. The aim of this study was to investigate the spatiotemporal dynamics of trees distribution patterns in a ten-year period following disturbance caused by decline in the oak forests of Lorestan province in the west of Iran. For this purpose, the quantitative characteristics and the spatial patterns of trees in 5-hectare sample plots in four different regions without decline, which were surveyed in 2010, also surveyed in 2020 which three regions had conditions of decline and one region without decline). Paired sample t-test was used to compare the averages at the beginning and end of the period, and analysis of variance was used between regions. Ripley’s K function was used to analyze the spatial patterns of trees. The results showed that the mean of density was decreased in declined areas and increased in the non-declined area during the period. During the ten-year period, there was a significant difference between the tree density and canopy percentage in the areas with and without decline. The spatial patterns of Persian oak (Quercus brantii) trees in the decline areas showed that during the period, the spatial patterns in the pure and low-density stands were clustered, while in the mixed stands with the dominance of oak with relatively high density, it was a random distribution pattern, which with increasing of distance, changed to clustered.
کلیدواژه‌ها [English]
)