Quantitative and Qualitative Characteristics of Hazelnut (Corylus avellana) in Arasbaran Forests
Identification of the future vegetative condition and the natural evolution of forest depends on analyzing its present and previous situation as well as predicting its future vegetative. Fandoghlou forest is the genetic and vegetative center and origin of hazelnut with a total area of 207.94 km2 (20794 hectares) within the boundaries of Ardabil province. In this research, the vegetative characteristics of hazelnut trees and other species – e.g., hornbeam, oak, beech and common hawthorn – which mainly consist of wooden species in Fandoghlou of Namin region, were recorded including diameter at breast height, basal area, freshness, reproduction based on systematic random (SR) sampling. Sampling intensity was 3.3% (since the forest is homogeneous) and sampling plots designed within a 150 × 200 m grid. The above gridding was initially implemented on a 1:10000 map from the region and it was performed in the region after its definitive determination in nature. A total of 33 plots each with an area of 1000 m2 was sampled in the desired region, which the plots covers over 3.3 hectares of the area. Each plot was circularly sampled within a radius of 17.84 cm. The sampling was performed by recording data for trees with >7.5 cm in diameter among various species at the end of the form as number, diameter, height, cross-sectional area, and volume; and the number of vegetative and reproductive sprouts was also recorded in the attached tables for trees with < 7.5 cm in diameter in two diameter classes of 0-2.5 cm and 2.5-7.5 cm. Characteristics of control trees for sample plots, which include the nearest trees to the plot center and the thickest tree in the plot, were measured and recorded. The required data were provided to prepare the curve for diameter, height, cross-sectional area, volume, regeneration for available species including hazelnut and other woody species. T-test was used in this study. Comparing the results of test showed that there is a significant difference between the volume, cross-sectional area, and the height of hazelnut and other species. All conditions for the conservation of hazelnut are provided, but for other species given that the hazelnut-oak type is one of the dominant types for the studied region, it is required to provide forest with marking more beech and hornbeam toward above dominance.