Determination of relationships between leaf area index and stand characteristics in crimean pine stands of Kastamonu region

In this study, it is aimed to determine the relationships between leaf area index (LAI) and some stand characteristics (quadratic mean diameter, stand age, dominant height, site index, number of trees, basal area, stand density, crown biomass and crown dimensions) for even-aged, pure and natural Crimean pine stands in Kastamonu region. For this purpose, the LAI and other stand characteristics were determined in 119 sample plots. The correlation analysis was used to evaluate the relationships between the LAI and stand parameters, and as a result, positive correlations have been found between LAI and stand density, basal area, number of trees, site index, dominant height, and crown biomass. ANOVA was used to examine of the LAI according to age, stand density and site classes. It was determined that there are significant differences in terms of stand density and site classes. To estimate the LAI using the stand characteristics, regression equations have been developed. For this purpose, parameter estimates were made for 11 regression models, seven of which were taken from the literature and the other four models were developed in this study. The models developed were compared with various statistical criteria (adjusted coefficient of determination (Radj2), mean error (ME), root mean square error (RMSE), Akaike information criterion (AIC)). According to the relative ranking results, the D-1 model, in which site index and stand density are included as independent variables, was the most successful regression model and it is appropriate to use for LAI estimates. Adjusted coefficient of determination (Radj2) and root mean square error (RMSE) values for the D-1 model were calculated as 0,631 and 0,44, respectively.