Ammonium, Nitrate, and Phosphate in Coastal Waters of Red River Biosphere Reserve, Vietnam

Abstract

Nutrient availability in coastal areas plays a crucial role in supporting primary producers and maintaining the aquatic food chain. The spatial variation of nutrients, including ammonium, nitrate, and phosphate, can significantly influence coastal ecosystems’ structure, leading to both positive and negative results. This study examines the fine-scale spatial variation of physicochemical parameters and nutrient concentrations in shrimp ponds and adjacent coastal waters from two wetland areas: Ba Lat Estuary (BLE) and Thai Thuy (TTW) in the Red River Delta, Vietnam. Ammonium concentrations ranged from 155.80 to 1,500.80 µg/L, with an average value of 666.83±260.02 µg/L. Nitrate concentrations varied from 25.10 to 996.40 µg/L, averaging of 285.42±255.05 µg/L, while phosphate concentrations exhibited significant variability, ranging from 0.70 to 128.70 µg/L. Nutrient concentrations in the RRD were relatively high compared to other regions globally. The findings revealed that tidal dynamics and aquaculture activities significantly influence nutrient variations in coastal waters. The increasing nutrient concentrations in the coastal marine environment of the Red River Biosphere could lead to eutrophication risks, which could adversely affect mangroves, estuarine areas, and other coastal ecosystems. This results emphasize the critical need to reduce nutrient discharge and implement wastewater treatment from anthropogenic activities to safeguard ecosystems and protect the coastal estuary environment. Further research is essential to investigate the spatial and temporal dynamics of nutrients in this region to fully understand their impacts on coastal marine ecosystems.

Keywords

• mangroves
• coastal nutrient dynamic
• eutrophication
• red river biosphere reserve