Dynamic assessment of changes in the statistical distribution of the canopy in the central Zagros forests with impact of the decline (Case study: Dadabad- Lorestan)

Document Type : Scientific article


1 Ph.D. student of Forestry, Faculty of Agriculture, Ilam University, Ilam, I.R. Iran

2 Assistant Professor, Department of Forestry, Faculty of Agriculture, University of Lorestan, Khorramabad, I.R. Iran


The main objective of this study was to estimate the effect of decline disturbance on canopy distribution of coppice oak trees in central Zagros region. For this purpose one similar stand with (32ha) in central Zagros (Dadabad in Lorestan province) was selected. Canopy of declined trees was recorded before and after cutting using 100% inventory method. Then Beta, Jonson, Weibull, Gamma, Normal and Log-normal distribution functions were applied. The results of goodness of fit tests suggested that Gama, Jonson and Weibull functions are fitted for introducing Canopy of woody stems in field, respectively, are suitable for Dadabad region. There was difference between before and after decline disturbance based on using statistical distribution. The results of goodness of fit tests for after decline suggested that Weibull, Jonson and Gama functions are fitted for introducing Canopy of woody stems is suitable for Dadabad region. Other distributions had not ability to evaluate this characteristic. Influence of decline in this region was in a way that does not impact on some categories of cover in the same way, so the canopy fitting pattern region has a significant impact. Scanning fitting canopy Zagros forests in different classes and in different time steps, the status of these forests in terms of ecosystem degradation and the process sequence, which in educational management problems and has many applications.


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