Modeling Leaf Area Index in Anatolian Black Pine Stands Across Different Ecological Regions of Türkiye

In this study, the relationships between effective Leaf Area Index, stand structural characteristics, topographic variables, and bioclimatic factors were modeled in pure and even-aged Anatolian black pine (Pinus nigra Arnold. subsp. pallasiana Lamb.) stands naturally distributed across different ecogeographical regions. The research was conducted in the Kastamonu and Muğla regions of Türkiye, and Leaf Area Index values were determined using hemispherical photography. Within the scope of the study, stand characteristics, including development stage, crown closure, and site quality, together with elevation, slope, Radiation Index, and 19 bioclimatic variables, were evaluated. The model development process was performed using the stepwise variable selection method based on the Akaike Information Criterion. According to the results, ecoregion, crown closure class, elevation, and BIO10 representing the mean temperature of the warmest quarter were identified as the most significant variables explaining Leaf Area Index variability. The model results indicated that Leaf Area Index increased with increasing crown closure, while elevation and growing season thermal conditions positively influenced canopy development. The developed model produced an root mean square error (RMSE) value of 0.218 and an RMSE% value of 18.204%. In addition, the Breusch–Pagan test demonstrated a homogeneous residual distribution. The findings revealed that Leaf Area Index is strongly associated not only with stand structure but also with bioclimatic and topographic gradients. The study contributes to a better understanding of canopy structure in coniferous stands across different ecogeographical regions and provides an important basis for developing more reliable regional-scale Leaf Area Index models.

Cite this article as: Pehlivan, S., Ediş, S., & Bolat, F. (2026). Modeling leaf area index in Anatolian black pine stands across different ecological regions of Türkiye. Forestist, 76, 0073, doi:10.5152/ forestist.2026.26073.