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Abstract. Dense vegetation that covers most landscapes in Indonesia becomes a common limitation in mapping the landforms in tropical region. This paper aims to examine the use of radar interferometry for landform mapping in tropical region; to examine the application of segmentation method to develop landform type boundaries; and to identify the topographic elements composition for each type of landform. Using Idrisi® and "eCognition ®" softwares, toposhape analysis, segmentation and multi-spectral classification were applied to identify the composition of topographic elements i.e. the types of land-cover from Landsat 8, elevation, slope, relief intensity and curvatures from SRTM (DEM). Visual interpretation on DEM and land-cover fusion imagery was conducted to derive basic control maps of landform and land-cover. The result shows that in segmentation method, shape and compactness levels are essential in obtaining land-cover, elevation, and slope class units to determine the most accurate class borders of each element. Despite a complex procedure applied in determining landform classification, the combination of topographic elements segmentation result presents a distinct border of each landform class. The comparison between landform maps derived from segmentation process and visual interpretation method demonstrates slight dissimilarities, meaning that multi-stage segmentation approach can improve and provide more effective digital landform mapping method in tropical region. Topographic elements on each type of landforms show distinctive composition key containing the percentage of each curvature elements per area unit. Supported by GIS programming and modeling in the future, this finding is significant in reducing effort in landform mapping using visual interpretation method for a very large coverage but in detail scale level. IntroductionThe application of remote sensing in geomorphic mapping has been developing vastly, coinciding with the launching of radar interferometry and its ability to provide digital surface/elevation model (DSM/DEM) [1]. One of the important parameters in geomorphic mapping is land physical characteristics information derived from landform classification and mapping, both in regional or global level. Landform, as the main element in geomorphic mapping, is a natural object feature that divides the earth surface into one main spatial unit [2]. It comprises the information of relief, elevation and the common land activities that dominating the landscape processes. DEM provides more promising data to the researchers in increasing the quality of landform mapping, because it consists of elevation information with 3-dimentional relief features. Nowadays, landform classification using DSM/DEM is one of basic research domain in digital terrain analysis, including GIS landscape integrated studies. The common free access and reliable 3-dimentional relief data used in many mapping applications is Shuttle Radar Topography Mission (SRTM) (Figure 1). This imagery has horizontal and vertical spatial ...

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Abstract. Teluk Jor has alluvium surface sediment that came from volcanic materials. Sea wave that relatively calm and the closed beach shape support the existence of mangrove forest at Teluk Jor. Sentinel-2A imagery has a good spatial and spectral resolution for mangrove density study. The regression between samples and the NDVI values of Sentinel-2A used to analyze the mangrove canopy density. Mangrove canopy density was identified using field survey with transect method. The regression analysis shows field data and NDVI value has correlation R=0.7739 and coefficient of determination R2=0.5989. The result of the analysis shows area of low density 397,900 m2, moderate density 336,200 m2, the high density has 110,300 m2 and very high density has 500 m2. This research also found that mangrove genus in Teluk Jor consists of Rhizopora, Ceriops, Aegiceras and Sonneratia.