Estimation of liana infestation above canopy in recreational park Bukit Bakar, Kelantan using unmanned aerial vehicle

A study on lianas estimation has been conducted in Bukit Bakar Recreational Park, Machang, Kelantan. Liana infestation on tree crowns was assessed from above by using an unmanned aerial vehicle (UAV), DTI Phantom-4 Pro which was manually piloted. Liana load carried by trees were determined by calculating the percentage liana cover (%LC) and measuring crown occupancy index (COI). Collection of image data by UAV had been captured and geo-tagged with GPS location. Liana infestation assessment was carried out to 1 ha area by cropping orthomosaics processed image and visual interpretation was viewed. The result of liana infestation was tabulated. The value of crown occupancy index (COT) depended on the accuracy of the percentage liana cover (%LC). There are 14 trees infested of lianas identified. The level of liana loads could be compared in graph. The value COT of 14 lianas-infested trees ranged from 0 — 2 which was very low or none, low and moderate. Point 2,3,4 and 11 covered moderate while point 9 covered very low or none levels of liana load on tree crowns and other points covered low levels. Elevation gradients, light availability, host interactions and seasonality affect the level of liana infestation. Spearman's rank correlation test was used to assess the concordance of the percentage liana cover (%LC) and measuring crown occupancy index (COI). This method could promote the local authority in forestry management particularly in managing the tree crown occupancy of liana in the logged-over forest.