(538g) Novel Strategies with Artificial Floating Islands for Water Bodies Restoration As Optimal Control Problems

Artificial Floating Islands (AFIs) consist of buoyant platforms with aquatic or native plants growing in hydroponic manner floating on the surface of water. These structures hold the plants so that the roots can uptake nutrients (mainly N and P) from the lake water column and improve the water quality (Chang et al. 2017). Also, AFIs have other benefits from the lake ecosystems such as entrapping suspended solids and creation of habitats for fish and birds (Nitturkar and Bhosale, 2019).

In this work, we propose the integration of a mechanistic water quality model of Paso de las Piedras reservoir (Siniscalchi et al., 2020) with an AFIs model within a dynamic optimization framework as an optimal control problem to address the restoration of a eutrophic water body through different restoration techniques. These strategies include previously implemented restoration techniques: artificial constructed wetlands on the lake tributaries, tributary bypass and biomanipulation (Siniscalchi et al. 2020), as well as the design of constructed artificial islands as internal remediation tools. The AFIs model includes mass balances for a native plant and the constructed AFI platform area as design variable. Numerical results allow analizing the performance of the different restoration strategies and the efficiency of their joint aplication on a nearby reservoir (Paso de las Piedras), which provides drinking water to a city with more than 400,000 inhabitants.

References

Chang, He Cui, Minsheng Huang, Yan He (2017), Artificial floating islands for water quality improvement, Environmental Reviews, https://doi.org/10.1139/er-2016-0038

Siniscalchi, A.G , J. Di Maggio, V. Estrada, M.S. Diaz (2020) Integrated Mathematical Models for Drinking Water Reservoirs and Constructed Wetlands as a Tool for Restoration Planning, Journal of Hydrology, 586, 124867, doi 10.1016/j.jhydrol.2020.124867

Nitturkar, R , Shrikant M. Bhosale (2019) Performance Evaluation of Artificial Floating Island for Nutrient Removal, International Journal of Engineering Research & Technology (IJERT), doi.10.17577/IJERTV8IS120022