A Model-Based Approach for Improving Surface Water Quality Management in Aquaculture Using MIKE 11: A Case of the Long Xuyen Quadangle, Mekong Delta, Vietnam

Abstract

This study utilized MIKE 11 to quantify the spatio-temporal dynamics of water quality parameters (Biochemical Oxygen Demand (BOD5), Dissolved Oxygen (DO) and temperature) in the Long Xuyen Quadrangle area of the Vietnamese Mekong Delta. Calibrated for the year of 2019 and validated for the year of 2020, the developed model showed a significant agreement between the observed and simulated values of water quality parameters. Locations near to cage culture areas exhibited higher BOD5 values than sites close to pond/lagoon culture areas due to the effects of numerous point sources of pollution , including upstream wastewater and out-fluxes from residential and tourism activities in the surrounding areas, all of which had a direct impact on the quality of the surface water used for aquaculture. Moreover, as aquacultural effluents have intensified and dispersed over time, water quality in the surrounding water bodies has degraded. The findings suggest that the effective planning, assessment and management of rapidly expanding aquaculture sites should be improved, including more rigorous water quality monitoring, to ensure the long-term sustainable expansion and development of the aquacultural sector in the Long Xuyen Quadrangle in particular, and the Vietnamese Mekong Delta as a whole.

Progress toward resilient and sustainable water management in the Vietnamese Mekong Delta

“…The potential for additional rice seasons is determined by geography and irrigation infrastructure. Overall, the region accounts for over 30% of the Vietnam agricultural GDP, producing 55% of Vietnam's rice, 65% of domestic aquaculture products, 70% of domestic fruit, 95% of exported rice and 60% of exported aquaculture products (Thu Minh et al, 2022; Ty et al, 2022).…”

“…Administratively the VMD is organized into 12 provinces and the province‐level city of Can Tho. It is incised with an extensive network of rivers, tributaries, canals, wetlands and drainage ditches, with branches of the Mekong River discharging water and suspended sediments into the East Vietnam Sea (Thu Minh et al, 2022) (Figure 1). The VMD is a complex fluvial to marine transitional zone, with fluvial processes dominating upstream zones, and tidal and estuarine processes dominating downstream sections (Biggs, 2012; Renaud & Kuenzer, 2012).…”

A sophisticated model for rating water quality

“…For the purposes of model efficiency analysis, the present study calculated the NSE and MEF using the actual and predicted IEWQI scores. Recently, a number of water research studies have utilized this tool to validate the model performance in terms of model efficiency (Guo et al, 2019;Izhar Shah et al, 2021;Jain and Sudheer, n.d.;Minh et al, 2022;Moriasi et al, 2015). Fig.…”

“…Recently, several scientific studies in various domains have utilized this technique for assessing the model's performance in terms of efficiently predicting (Chaudhary and Hantush, 2017;Rahman, 2020;Rahman and Harding, 2016;Uddin et al, 2022d). It allows measuring and determining the magnitude of residual variation in a comparison to recorded data variance (Izhar Shah et al, 2021;Minh et al, 2022). Details of the NSE index can be found in McCuen et al (2006).…”

Hydrological Impact of Ilisu Dam on Al-Gharraf River in southern of Iraq using MIKE11 Hydrodynamic Model

“…The model solves the unsteady state flow equations using the double sweep technique and the finite difference method [19]. It can be used to simulate any size and gradient of river, from tidal estuaries to steep torrents [20]. The flow and water level at the boundaries can be steady or can vary with time.…”