Analisis Sebaran dan Kerapatan Mangrove Menggunakan Citra Sentinel-2A di Bandar Bakau Dumai

Abstract

Mangrove merupakan tumbuhan yang hidup di daerah pesisir pantai yang berfungsi sebagai habitat biota laut, dan melindungi garis pantai. Penelitian ini bertujuan memetakan sebaran, luasan, dan kerapatan mangrove di Bandar Bakau Dumai pada tahun 2022 menggunakan citra Sentinel-2A. Data lapang yang dibutuhkan yaitu foto tutupan kanopi dan titik koordinat pengambilan data. Perhitungan persentase tutupan mangrove dihitung menggunakan metode hemispherical photography. Indeks vegetasi dari citra satelit dihitung menggunakan algoritma NDVI. Uji akurasi klasifikasi citra menggunakan metode MLH. Terdapat 10 jenis mangrove yang ditemukan di wilayah penelitian dan didominasi oleh Rhizophora apiculate dan Xylocarpus granatum. Nilai tutupan kanopi mangrove hasil pengamatan berkisar antara 89,2% hingga 31,14%. Nilai indeks vegetasi dilokasi kajian pada tahun 2022 dengan metode NDVI berkisar pada -0,195 hingga 0,775. Luas sebaran mangrove di Bandar Bakau Dumai pada tahun 2022 sebesar 35,52 ha dengan dua tipe kerapatan yaitu mangrove rapat dan mangrove sedang. Hasil uji akurasi klasifikasi citra sebesar 81,63%. Hasil koefisien korelasi antara tutupan kanopi dan NDVI sebesar 75% tergolong korelasi tinggi. Penelitian ini menunjukkan nilai NDVI dapat menjadi acuan nilai tutupan kanopi mangrove.

Mangroves are plants that live in coastal areas that function as a habitat for marine life and protect the coastline. This studied aim to map the distribution, area, and density of mangroves in Dumai Bakau Airport in 2022 using Sentinel-2A imagery. The required field data were photos of canopy cover and coordinate points for data collection. Mangrove cover percentage was calculated using the hemispherical photography method. Vegetation index from satellite imagery was calculated using NDVI algorithm. Image classification accuracy test was using MLH method. There were 10 mangrove species found in the study area and were dominated by Rhizophora apiculate and Xylocarpus granatum. The observed mangrove canopy cover value ranged from 89.2% to 31.14%. The vegetation index valued at the study location in 2022 using the NDVI method ranges from -0.195 to 0.775. The distribution area of mangroves in Dumai Bakau Airport in 2022 was 35.52 ha with two types of density, namely very dense and dense mangroves. The result of image classification accuracy test was 81.63%. Correlation coefficient between canopy cover and NDVI of 75% was classified as high correlation. This studied show that the NDVI value can be used as a reference for the mangrove canopy cover value.