5th INTERNATIONAL CONGRESS ON KHAZAR SCIENTIFIC RESEARCH AND INNOVATION
DETERMINATION OF THE MOST APPROPRIATE DISTRIBUTION FUNCTION IN PREDICTING THE DIAMETER DISTRIBUTIONS OF OAK STANDS IN KASTAMONU REGION
This study aims to determine the most appropriate distribution function that can be used in predicting the diameter distribution of oak (Quercus sp.) stands in Kastamonu region, Türkiye. For this purpose, a total of 71 sample plots were taken from natural and pure oak stands in Kastamonu and Karadere Forest Enterprises. The diameter of breast height of all standing trees with diameters of 8 cm and above was measured in the sample plots. The diameter distributions of the sample plots were modeled with six probability density functions including Beta, Gamma, Johnson SB, Lognormal, Normal and Weibull. Then, the developed models were ranked in terms of their success according to three statistical criteria (Kolmogorov-Smirnov (KS), Anderson-Darling (AD) and Chi-square (X2)). As a result, the most successful distribution function that can be used in predicting the diameter distribution of oak stands in Kastamonu region was decided. In addition, the effects of stand development stage, crown closure and stand type on the success rankings of distribution functions were also investigated. According to the study results, Gamma and Johnson SB functions have successful estimations in modeling the diameter distributions of oak stands in the Kastamonu region.
