Analysis of Plankton Abundance Based on The Year of Mangrove Planting in Kaliwlingi Village, Brebes Regency

Abstract

This study aims to analyze the abundance, diversity, uniformity, and dominance of plankton based on the differences in mangrove planting years in Kaliwlingi Village, Brebes Regency. Sampling was conducted at four stations representing the mangrove planting years of 2010, 2015, 2017, and 2018. A total of 30 L of surface water was filtered using a 25 µm plankton net and preserved with 1% Lugol's iodine solution. Plankton identification was carried out to the genus level. Data analysis included abundance (cells/mL), Shannon–Wiener diversity index (H'), Pielou uniformity index (E), and Simpson dominance index (C). The results identified 13 phytoplankton genera belonging to the classes Chlorophyceae, Bacillariophyceae, Haptophyceae, and Cyanophyceae, while no zooplankton were found. The highest plankton abundance was recorded in the 2010 planting area (1,955,000 cells/mL), while the lowest abundance was observed in the 2015 planting area (1,502,500 cells/mL). The Shannon–Wiener diversity index (H') ranged from 0.730 to 0.887, indicating low diversity, the evenness index (E) ranged from 0.408 to 0.551, and the dominance index (C) ranged from 0.460 to 0.608, indicating moderate dominance in all planting years. Chlorella was the most abundant genus in all planting areas. These findings suggest that differences in mangrove planting years are associated with variations in plankton abundance and community structure in the Kaliwlingi mangrove ecosystem.