Keanekaragaman Nekton di Kawasan Mangrove Pantai Muara Indah Kecamatan Pantai Labu Kabupaten Deli Serdang Provinsi Sumatera Utara

Abstract

Mangroves and nekton have a close relationship within coastal ecosystems. Mangroves provide and shelter for nekton, such as fish, shrimp, and crabs. Mangroves also contribute to the food chain by releasing organic matter that decomposes into detritus, serving as a food source for nekton. This ecosystem supports high biodiversity and helps maintain the balance and sustainability of nekton populations. This study applied an ecological analysis approach to identify patterns of diversity, evenness, and species dominance within a specific ecosystem. The diversity index (Shannon-Wiener), evenness index (Pielou), and dominance index (Simpson) were used to quantitatively evaluate the structure of biotic communities. Additionally, the Canonical Correspondence Analysis (CCA) method was applied to link species distribution variations with influencing environmental factors. The diversity index (H') at Station I, II, and III are 0.44, 0.40, and 0.45, respectively. The dominance index (Di) at Station I, II, and III are 30.7, 7.69, and 25.2, respectively. The evenness index (E) at Station I, II, and III are 0.08, 0.07, and 0.08, respectively.The physical and chemical parameters in the mangrove area of Pantai Muara Indah, such as temperature, pH (7.6–7.7), DO (>5 mg/L), salinity, nitrate, and phosphate, affect habitat quality and the sustainability of nekton. Sufficient DO supports organism respiration, while high phosphate levels (>0.8 mg/L) can trigger eutrophication, which negatively impacts the ecosystem. This data underscores the importance of environmental suitability for the sustainability of nekton ecosystems