LiDAR-DERIVED ELEVATION AND TERRAIN FOR REPLANTING OPERATION OF OIL PALM IN MALAYSIA

ABSTRACT: Malaysia currently holds a pool of 365,414 ha. of oil palm trees older than 25 years; these oil palms have exceeded their prime production age and need to be replaced with higher yielding oil palm seedlings. Application of advanced technology has been considered as one of the approaches to improve plantation practices of plantation management companies such as the government-owned FELDA. In this study, the accuracy estimates of derived digital model (DSMs) constructed using LiDAR dataset will be investigated towards its role for oil palm replanting program in Malaysia. The accuracy of the derived LiDAR DEM is determined using check points based on conventional surveying technique and GPS. A total of 50 ground control points were used to evaluate the vertical accuracy of the dataset. It was found that the accuracies of the constructed LiDAR DEM in the study were better than expected, despite the undulating hilly nature of the study area. The RMSE value is 0.4 m, which indicates the suitability of the method for this purpose. The LiDAR-determined ground point heights are well correlated to those measured in the field, although the LiDAR heights in certain points underestimated the field heights. This underestimation is believed to be due to signal threshold limits within the LiDAR. The most significant advantage of the approach is that it allows plantation managers to accurately plan plantation roads and determine the planting point for new oil palm trees. As a conclusion, the results from this work show that LiDAR provide valuable and complementary information at a certain range of scales and can assist managers to make more informed resourc