Population Structure and Spatial Distribution of Tree Species in Lower Montane Forest, Doi Suthep-Pui National Park, Northern Thailand
Authors:   Department of Forest Biology, Faculty of Forestry, Kasetsart University, Bangkok 10900, Thailand, Marod Dokrak , Duengkae Prateep ,   Department of Forest Biology, Faculty of Forestry, Kasetsart University, Bangkok 10900, Thailand, Sangkaew Sarawood ,   Department of Forest Biology, Faculty of Forestry, Kasetsart University, Bangkok 10900, Thailand, Racharak Phruet ,   Department of Forest Biology, Faculty of Forestry, Kasetsart University, Bangkok 10900, Thailand, Suksavate Warong ,   Department of Forest Biology, Faculty of Forestry, Kasetsart University, Bangkok 10900, Thailand, Uthairatsamee Suwimon ,   Department of Forest Biology, Faculty of Forestry, Kasetsart University, Bangkok 10900, Thailand, Asanok Lamthai ,   Department of Agroforestry, Maejo University Phrae Campus, Phrae 54140, Thailand, Kamyo Torlarp ,   Department of Agroforestry, Maejo University Phrae Campus, Phrae 54140, Thailand, Thinkampheang Sathid ,   Cooperation Centre of Thai Forest Ecological Research, Kasetsart University, Bangkok 10900, Thailand, Heumhuk Sutheera ,   Faculty of Agricultural Production, Maejo University, Chiang Mai 50290, Thailand, Kachina Panida ,   Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Thongsawi Jakkapong ,   The Foundation of Mrigadayavan Palace under the Patronage of Her Royal Highness Princess Bejaratana,  Phetchaburi 76120, Thailand, Phumpuang Wongsatorn ,   Department of National Parks, Wildlife and Plant Conservation, Bangkok 10900, Thailand, Paansri Paanwaris ,   Cooperation Centre of Thai Forest Ecological Research, Kasetsart University, Bangkok 10900, Thailand, Nuipakdee Wimonmart ,   Mae Sa-Kog Ma Biosphere Reserve, Chiang Mai 52000, Thailand, Nakmuenwai Pisut ,   Faculty of Environment and Resource Studies, Mahidol University, Nakhon Pathom 73170, Thailand, Pattanakiat Sura ,   Faculty of Environment and Resource Studies, Mahidol University, Nakhon Pathom 73170, Thailand
Published: September 2022

Plant diversity is important for sustainable development, particularly in watershed areas. This study explored tree population and diversity in a lower montane forest (LMF). A 16-ha permanent plot was established in LMF at Huai Kogma sub-watershed, northern Thailand. All trees with a diameter at breast height ≥ 2 cm were tagged, measured, identified, and their coordinates were mapped. The results showed that 220 species in 139 genera from 63 plant families were found. The dominant families based on species numbers and tree density were Fagaceae, Lauraceae, and Theaceae. The most dominant species were Castanopsis acuminatissima, Schima wallichii, Castanopsis armata, and Styrax benzoides. Diameter classes for climax species frequently followed negative exponential distributions, indicating their populations could be maintained into the future. By contrast, pioneer species, such as Macaranga indica, Morus macroura, and Rhus javanica, had discontinuous distribution, and were mostly found in gap areas, indicating successful regeneration may require high light intensity. Spatial distribution patterns based on Morisita’s index showed that most of the selected species had clumped patterns, particularly those in the Fagaceae family, which were predominantly distributed along the mountain ridge. Tree distribution patterns can affect ecological dynamics, thus reinforcing patterns dependent on local interactions such as the abundance of and distance to available resources. Our finding can aid evaluations of forest sustainability, and support the biodiversity conservation plans. In particular, the selection of suitable species for LMF restoration programs where mixed plantings of pioneer and climax species are planned.