Analisis Laju Sedimentasi di Kawasan Pantai Mangrove Paluh Getah, Desa Percut, Kecamatan Percut Sei Tuan, Kabupaten Deli Serdang

Abstract

Mangrove coastal areas are important ecosystems that play an ecological role in stabilizing coastlines and trapping sediments. However, damage to mangrove forests due to land conversion has increased vulnerability to abrasion and changes in coastlines. This study aims to analyze sedimentation rates, determine sediment texture types, and assess the suitability of sedimentation rates and sediment texture types for the mangrove ecosystem in the Paluh Getah Mangrove Beach area, Percut Village, Percut Sei Tuan District, Deli Serdang Regency. This study was conducted in August 2025 using a quantitative descriptive method with primary data collection in the form of suspended sediments and environmental parameters (current and depth), as well as secondary data such as tidal data, rainfall, and RBI maps. Station points were determined using purposive sampling. Sediment samples were collected using sediment traps installed at five cylindrical observation stations placed in the water for 7 days and analyzed using a volume formula to calculate the sedimentation rate. Texture analysis was performed using a pipette method and classification based on a soil texture triangle diagram. The results showed that the highest sedimentation value was recorded in the second week at 0.484 mm/week, while the lowest value occurred in the first week at 0.081 mm/week. This shows that environmental conditions at each sampling point greatly affect the amount of sediment deposited, in terms of currents, water bottom topography, and proximity to sediment sources. Based on the weekly average, the highest sedimentation occurred in the second week at 0.309 mm/week, while the lowest sedimentation occurred in the first week at 0.186 mm/week with an average of 0.268 mm/week or equivalent to 13.9 mm/year. The sediment texture at all observation stations was dominated by clay, indicating a stable substrate capable of retaining water and nutrients, which is very suitable for the growth of Rhizophora sp. and Avicennia sp. mangroves. However, with the sedimentation rate obtained, it is estimated that the time required to reach the optimal sediment thickness for mangrove growth is around 18-25 years for Rhizophora and around 11-18 years for Avicennia sp.