Vegetation structure characteristics and Gluta usitata (Wall.) Ding Hou site identification of deciduous dipterocarp forest in Gluta usitata conservation and development of local knowledge using lacquer sap under the Royal Initiative Project, Chiang Mai

Abstract

The study of plant community characteristics of Gluta usitata (Wall.) Ding Hou habitat related to environmental factors that emphasize the potential of conservation and utilization of G. usitata lacquer sap in natural forest. This study aimed to study the structure and habitat suitability of G. usitata in Project of G. usitata conservation and development of local knowledge using lacquer sap under the Royal Initiative Project, Chiang Mai Province. Thirty sample plots based on systematic sampling plot were set up. In each plot, all species composition and environmental factors that affected G. usitata were collected. The results showed that, 54 species 47 genera in 24 family were found with, and species diversity index was 2.86. Stems density and basal area of tree were 1,386 stem ha-1 and 30.87 m2ha-1, respectively. The cluster analysis revealed that showed 4 stands; Dipterocarpus tuberculatus - Pinus merkusii stand (DPS), Castanopsis diversifolia - Dipterocarpus tuberculatus stand (CDS), Dipterocarpus tuberculatus - Craibiodendron stellatum stand (DCS), and Shorea siamensis - Lithocarpus sootepensis stand (SLS) were detected. The stems density and basal area of G. usitata were showed that 93 stem ha-1 and 2.57 m2 ha-1, respectively. The relationship model between environmental factors and G. usitata using linear regression analysis with high accuracy level (88 %) shown that the positive significant factors included elevation, aspect, distance from river, temperature, pH, N, K, and Mg. In contrast, the negative significant factors were slope, convexity, rainfall, organic matter, P, Ca, and clay. The natural potential site identification for G. usitata using GIS can be divided into three levels; high, moderately and low which covered areas of 4,392.33, 2,722.48 and 919.01 hectare, respectively. Thus, the management of G. usitata for utilization and conservation should be considered the suitable environmental factors to increase the G. usitata habitat suitability.

Keywords: Deciduous dipterocarp forest, Species diversity, Gluta usitata, Geographic Information Systems (GIS)

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