Coastal morphodynamic and assessments of coastal vulnerability index in Parepare bay

Abstract

The purpose of the study is to assessments the coastal vulnerability index in the Parepare bay, the beach is Lojie area, District of Mallusetasi, Barru Regency, Lumpue and Lapakaka areas, District of Bacukiki, City of Parepare South Sulawesi Province with including some aspect that is morphodynamic, coastal characteristic, hydro-oceanography, and coastal vulnerability index. Geomorphology in the study area was grouped in the formation of the morphology of terrain, wavy, and hills. Stratigraphically is composed of Parepare Volcanic rocks (Tppv), and Alluvial Deposits (Qa), divided into 4 rock units namely alluvial units, trachyte unit, tufa unit, and volcanic breccias. unit. Based on that, coastal characteristic in research area divisible in 3, that is rock coastal, sandy coastal and mud/mangrove coastal. Hydro-oceanography condition in research area that is about current with velocity of current average is 0,191 m/s with direct current is N 97? E (southeast), wave with average of high wave velocity of current average is 0,191 m/s with direct current is N 97? E (southeast), wave with average of high wave is 56,40 cm, velocity of wave is 2,4 m/s and wave maximum energy as big as 10368 joule, tide subsides in research area with high tide 1.3 meters and low subside is 0,6 meters with sea-level high 1 meters. Coastal morphodynamics and vulnerabilities of the Parepare Bay on the northern part of Lumpue Coastal, which was dominated by sand-sized sedimentary material, found multiple bars due to low/weak energy wave activity, sloping beach morphology, and predominantly residential areas. It is thus categorized as a dissipative type beach with a low level of vulnerability (CVI = 6). As for the south of the study area, the Lapakaka Coastal and Lojie Coastal are dominated by gravel and coarse-sized sedimentary material, found coral reef fragments due to high energy wave activity and mangrove found in coastal areas. Then this beach can be classified in the type of reflective with a high level of vulnerability (CVI = 53.66 n 37.94).