Tropical deforestation monitoring using NDVI from MODIS satellite: a case study in Pahang, Malaysia

Abstract

Malaysian tropical forest vegetation cover type has experienced a continuous degradation and defragmentation during the past two decades. This study examined the tropical forest land cover density and conditions using Normalised Difference Vegetation Index (NDVI) observations derived from Moderate Resolution Imaging Spectroradiometer (MODIS) imageries specifically in Pahang, Malaysia. Prior to classification, the images were geometrically corrected to a common map projection. A set of 1294 random spatially distributed points was analysed to investigate the accuracy assessment of the NDVI classification. The results show that 96% of the total area were classified as the forest cover type in 2002 and only 87% in 2015. It was found that a total of 8.9% (0.22 mHa – 250m) and 6.6% (0.16 mHa – 1km) forest were degraded from the study area, mostly happens at the southern region. The four images classifications are having 70 – 90 % accuracy (Kappa coefficient = 0.4 to 0.5) and shows that imagery with higher resolution (250-m) has a better assessment. In conclusion, MODIS imagery can obtain information about the forest vegetation and can be more broadly applicable with various method combinations for forest degradation investigation.