The ecological effect of altitude gradient on the abundance of wood fungi in Darabkola educational research forest, Sari

Background and objectives: The altitude gradient is one of the important ecological factors in the distribution of different types of plant species in forest ecosystems, and the origin of altitude from sea level is related to the difference in altitude from open waters. The change in height from sea level, along with the change in vegetation, can affect the abundance of wood fungi. This research was conducted with the aim of studying the ecological effect of the altitude gradient on the abundance of wood fungi on beech species at different altitudes.
Methodology: In total, 15 pure beech logs were randomly selected in three altitude gradients: (first) 550 to 650, (second) 650 to 750, and (third) 750 to 850 meters above sea level, in the educational and research forest of Darabkala Sari. To collect samples of wood macroscopic fungi, after observing the fungal samples, each sample was taken in a healthy, complete, and suitable form for identification based on morphological characteristics. Height characteristics from sea level and dry land were recorded with a positioning device, and the samples were transferred to the mycology laboratory for identification. To measure the microscopic organs, 20 samples of each of these organs were measured using a microscope with a graduated lens. Finally, to identify different fungal arrays, identification was based on both macroscopic and microscopic features, using various sources. To categorize the abundance of fungi in different altitude gradients, statistical calculations and cluster analysis were carried out in PAST software, using the Ward and Lesser Eghlidis distance, and analysis of principal components for different altitudes, species, abundance, relative frequency, and standard index were checked in PAST software by comparing two groups of fungi. Additionally, to check for height differences, multiple analyses and double plotting were done in Minitab software to reveal the groupings in terms of cloud points and distribution of wood fungi.
Results: The obtained results showed that in the first height class, 13%, in the second 30%, and in the third 57% of all fungi were included. In the first height class, Hypholoma fasciculare was the most abundant, while Trametes versicolor dominated the second class, and Schizophyllum commune was the most abundant in the third class. Furthermore, the Polyporaceae, Xylariaceae, Ganodermataceae, Pleurotaceae, and Schizophyllaceae families had the highest frequency, while the Pezizaceae and Hericiaceae families had the lowest frequency. The results indicated that 10 species were distributed in the altitude class of 550 to 650 meters above sea level, 15 species were distributed in the altitude class of 650 to 750 meters above sea level, and 22 species were distributed in the altitude class of 750 to 850 meters above sea level. In addition, the most fungi families in the first altitudinal class were from the Meruliaceae family, whereas the second and third classes were primarily Polyporaceae. The analysis with Minitab showed that there is a significant difference in the distribution of wood fungi between the third and second floors, as well as between the first floor and the others. The findings regarding the ecological effect of the altitude gradient indicated that decomposition components reveal differences in fungi at different altitudes above sea level. These results showed that Fomes fomentarius, Ganoderma lucidum, Stereum hirsutum, Daldinia concentrica, Pleurotus ostreatus, Trametes versicolor, Trichaptum biforme, and Schizophyllum commune were among similar groups that were distributed across all three altitude classes, primarily within the Polyporaceae family and the Polyporales order.
Conclusion: The macroscopic wood fungi of the forest exhibit different responses across various gradients. The results of this study showed that the altitude gradient affects the abundance of wood fungi; the abundance of fungal species increases with elevation above sea level.