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

Abstract

A study on lianas estimation has been conducted in 1 ha plot at Bukit Bakar Recreational Park, Machang, Kelantan. Liana infestation on tree crowns was assessed from above by using an unmanned aerial vehicle (UAV), DJI 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. The value of crown occupancy index (COI) depends on the accuracy of the percentage liana cover (%LC). Fourteen host trees infested by lianas were identified. The value COI of 14 lianas-infested trees were in the range between 0 - 2, indicating low and moderate infestation. One point was recorded with very low liana load, nine points with moderate liana and four points with low liana load on tree crowns with 0.76% to 29.9% of liana cover respectively. The moderate and lower values obtained was probably due to the lesser of anthropogenic disturbance and natural disturbance that occurred after 40 years of selective management system logging. The liana infestation was distributed homogeneously. The lower liana COI obtained, indicates the ongoing progress of forest succession in Bukit Bakar that gradually hindered liana proliferation within the proximity. This method could promote the local authority in forestry management particularly in managing the tree crown occupancy of liana in the logged-over forest.