SPATIAL DISTRIBUTION AND ASSOCIATION PATTERNS OF HOPEA PIERREI HANCE AND OTHER TREE SPECIES IN THE PHU QUOC ISLAND EVERGREEN BROADLEAVED FOREST OF VIETNAM

The present study was conducted to better understand the ecology, spatial patterns and associations of Hopea pierrei - a vulnerable plant in the Vietnam Red Book and on the IUCN's Red List - in the medium natural evergreen broadleaved forest of Phu Quoc National Park, Kien Giang Province, Vietnam. Data was collected from all woody tree individuals with a diameter at breast height (dbh) >= 2.5 cm in three 1-ha plots (100 m x 100 m). The spatial point-pattern analysis method was used to analyze the data with Programita Noviembre 2018 and R 4.1.1 software. Our findings suggested that H. pierrei was aggregated and randomly distributed at various scales in the area where it appeared. The spatial patterns of H. pierrei were influenced by environmental heterogeneity. The intraspecific associations of H. pierrei were mainly attraction associations, while its interspecific associations with sixteen dominant species were mainly independent. Processes such as seed dispersal and self-thinning are the main mechanisms underlying the spatial patterns and associations of H. pierrei. Based on the present findings, it is possible to regulate density and choose an appropriate planting-hole distance when restoring forests or planting new forests with H. pierrei and dominant species with which it grows.