Comparative Study of Sediment Properties between Nypa Fruticans-Dominated and Rhizophora-Dominated Forests in Iko Creek

This study provides a comparative analysis of sediment properties and ecological impacts in Nypa fruticans and Rhizophora racemosa-dominated mangrove ecosystems within the Iko River estuary, Nigeria. Nypa fruticans, initially introduced to combat erosion, has spread extensively, often displacing the native Rhizophora racemosa and forming stands that alter local sediment properties. The study assessed parameters including pH (6.06–8.05), dissolved oxygen (DO; 2.5–4.7 mg/L), salinity (22–30 ppt), organic carbon (0.43–2.81 mg/kg), and organic matter (5.79–7.41%), revealing significant differences (p < 0.05) between the two vegetation types. Rhizophora-dominated sites showed higher organic carbon and DO levels, supporting better nutrient cycling and water quality, while Nypa-dominated sites exhibited elevated silicate levels and lower electrical conductivity, indicating possible change in the sediment profile which may impacts the habitat suitability and nutrient availability for native species. The findings highlight a critical research gap in understanding the long-term ecological effects of Nypa fruticans invasion on sediment chemistry and biodiversity, particularly heavy metal accumulation and microbial dynamics in sediment profiles. This study contributes to existing knowledge by providing baseline data on sediment properties and identifying key areas for further investigation, including microbial interactions and heavy metal bioaccumulation in invaded mangrove systems. The insights gained underscore the need for conservation and targeted management strategies to preserve Rhizophora racemosa habitats, which play a crucial role in sustaining biodiversity and enhancing ecosystem resilience against climate change.