J. For. Sci., 2021, 67(8):367-375 | DOI: 10.17221/150/2020-JFS

Distribution attributes of natural canopy gaps in the Hyrcanian mixed-oriental beech forestsOriginal Paper

Asadollah Mataji¹, Ali-Asghar Vahedi^*,2

¹ Department of Forestry, Faculty of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran

² Research Department of Natural Resources, Mazandaran Agricultural and Natural Resources Research and Education Center, AREEO, Sari, Iran

One of the most important issues indicating the quality and quantity of forest ecosystems is the distribution of natural disturbances resulting in canopy gaps (CGs). The present study was conducted in one of the Hyrcanian beech forests in northern Iran in summer 2018. The gap areas were classified into small (< 200 m²), medium (200‒500 m²) and large gaps (500-1 000 m²) on the basis of full inventory. The univariate Ripley's L-function was used for introducing the CG spatial pattern. Furthermore, mark correlation function (MCF) and density function (DC) in turns were used for verifying the correlation and frequency of CG size classes in each pattern. The results showed patterns of the gaps in each size class and integrated by the three size classes, they were random and cluster, respectively. Furthermore, the MCF revealed that the gap size classes were independently located in the clusters. The total frequency of the small, medium and large gaps in turns was 32, 49 and 19%, respectively. Although the density share of medium and small gaps in turns was more frequent than the large gap density in the study forest, the results of DC indicated that the frequency of each gap size class was random within each cluster, regardless of their density share. Based on the natural gap aggregations, the base circular mosaic with an area of 5 000 m² can be introduced for monitoring and specifying the forest stand dynamics.

Keywords: clustered pattern; disturbance; Hyrcanian forest; stand mosaic

Published: August 9, 2021  Show citation