Environmental capacity assessment for Amoni and TSS in Dung Quat Bay, Viet Nam

Abstract

Vietnam has a more than 3,260 km coastline. It discharges anually to the marine about 847 billion m3 of water and over 250 million tons of sediment, accompanied by a large amount of nutrients and pollutants. However, the general assessment problem environmental capacity and carrying capacity of water bodies are still not paid attention in. In this study, carrying out an assessment of environmental capacity in Dung Quat Bay where many economic activities are taking place and negatively impact on the coastal environment. The combination of calculating the environment capacity proposed by Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP) and tissue hydrodynamics and water quality modeling pakegae Mike21 has conducted environmental capacity assessment according to two typical seasons of the study area. The results show that, in the dry season, if compared with the standards of aquaculture, aquatic conservation, NH4+ is no longer able to bear the load; however, compared to water standards for beaches and water sports, NH4+ still has the capacity to bear the load of 0.029 (ton/day) and 2,231 (tons/day) at low and high tide, respectively. With TSS, it can withstand about 7 tons to 370 tons per day corresponding to low tide and high tide in the dry season. Moreover, in the rainy season, NH4+ is no longer able to bear the load in all cases; TSS also has environment capacity of about 160 (tons/day) at the low tide and 660 (tons/day) at the high tide.