Tropical Forestry

Visitor insects of Ooia spp. (Araceae) at Kinabalu UNESCO Global Geopark, Sabah, Malaysia

2025-08-26T16:55:55+08:00

The study was conducted at Kinabalu UNESCO Global Geopark (Kinabalu Geopark), Sayap Substation and Poring Substation to study the visiting insect’s interactions with two species of Ooia (Araceae). This study aimed to observe and identified the visitor insects for both Ooia species, analyzed the overlap of visiting insects between the two plant species of Ooia sayapensis and O. kinabaluensis, and to determine the difference in the number of the two species receiving visits from insects. Total of 124 individual insects were recorded, consists of six families including Staphylinidae, Erotylidae, Blattidae, Formicidae, Vespidae, and Drosophilidae. The Wilcoxon data analysis showed no significant difference (p>0.05) for the overlap of visiting insects in the two species of Ooia. However, the number of insect visits on O. sayapensis Kartini was higher (Day-1= 32% and Day-2= 33%) than O. kinabaluensis (Bogner) S.Y.Wong & P.C.Boyce (Day-1= 23% and Day-2= 16%) respectively. The difference of insect visitation rates between the two Ooia species suggest there is multiple factors influence their ability to attract insects. This study will add fundamental data on visitor insects of Ooia sayapensis within its habitat.

Natural Durability and Biodeterioration Resistance of Two Fast-Growing Tropical Tree Species: A Comparative Assessment of Acacia mangium and Leucaena leucocephala

2025-11-04T15:02:11+08:00

This study compared the natural durability and termite resistance of wild small-diameter Acacia mangium and Leucaena leucocephala wood under tropical field conditions. Specimens (30 cm × 2.5 cm) were exposed for 12 weeks in a graveyard test following ASTM D1758-06 standards at the Universiti Malaysia Kelantan (UMK) Jeli Campus. Decay and termite damage were assessed through visual ratings, weight loss analysis, and termite identification. Results showed that A. mangium exhibited significantly lower weight loss (30.54%) than L. leucocephala (51.95%) (p < 0.05), indicating higher natural resistance. The dominant termite species identified was Coptotermes curvignathus Holmgren. The superior durability of A. mangium is attributed to its higher content of extractives such as tannins and phenolics that inhibit fungal and termite activity. Findings classify A. mangium as moderately durable (Class II–III) and L. leucocephala as less durable (Class III–IV), emphasizing the need for preservative treatment in tropical applications.

Kewords: Acacia mangium; Leucaena leucocephala; natural durability; termite resistance; biodeterioration