Depth‐averaged, spatially distributed flow dynamic and solute transport modelling of a large‐scaled, subtropical constructed wetland

Abstract

Abstract:Constructed wetlands are being utilized worldwide to effectively reduce excess nutrients in agricultural runoff and wastewater. Despite their frequency, a multi-dimensional, physically based, spatially distributed modelling approach has rarely been applied for flow and solute transport in treatment wetlands. This article presents a two-dimensional hydrodynamic and solute transport modelling of a large-scaled, subtropical, free water surface constructed wetland of about 8 km 2 in the Everglades of Florida, USA. In this study, MIKE 21 was adopted as the basic model framework. Field monitoring of the time series hydrological and chloride data, as well as spatially distributed data such as bathymetry and vegetation distribution, provided the necessary model input and testing data. Simulated water level profiles were in good agreement with the spatio-temporal variations of measured ones. On average, the root-mean-square error of model calibration on annual water level fluctuations was 0Ð09 m. Manning's roughness coefficients for the dense emergent and submerged aquatic vegetation areas, which were estimated as a function of vegetation type, ranged from 0Ð67 to 1Ð0 and 0Ð12 to 0Ð15 s/m 1/3 , respectively. The solute transport model calibration for four monitoring sites agreed well with the measured annual variations in chloride concentration with an average percent model error of about 15%. The longitudinal dispersivity was estimated to be about 2 m and was more than an order of magnitude higher than the transverse one. This study is expected to play the role of a stepping stone for future modelling efforts on the development and application of more advanced flow and transport models applicable to a variety of constructed wetland systems, as well as to the Everglades stormwater treatment areas in operation or in preparation.

Hydrodynamic modelling of free water-surface constructed storm water wetlands using a finite volume technique

“…They also discussed the influence of three factors, including the aspect ratio of the wetland, the configuration of the inlet and outlet, and obstruction selection on the hydraulic efficiency. Furthermore, Min and Wise [15] presented a two-dimensional hydrodynamic and solute transport model of a large-scale, sub-tropical, FWS CW using the MIKE21 model.…”

Spatiotemporal Dynamics of Ammonia Nitrogen and Its Response to Inflow River Based on Random Forest Model in Northwest Taihu Lake, China

“…Therefore, this study focuses on the spatiotemporal dynamics of NH4 + -N and its response to inflow river. In the interactional study of eutrophication, hydrodynamics and ecosystem in various freshwater bodies, lots of mathematical modelling approaches have been extensively applied to simulate the flow, water quality, spatiotemporal pattern of hydrodynamics and so on (Rasmussen et al, 2009;Min and Wise, 2010;Zhang et al, 2017). For instance, Mike21, a two-dimensional mathematic model, has been usually used to calculated aquatic environment capacity and total emission reduction according to aquatic environmental functions and targets (DHI, 2007;Zhu et al, 2013;Zhang, 2017).…”

Envisat/ASAR Images for the Calibration of Wind Drag Action in the Doñana Wetlands 2D Hydrodynamic Model

“…Current hydrodynamic modeling of wetlands and shallow reservoirs is normally taken into account using 2D depth averaged models based on either wastewater treatment or overseas experience [17][18][19].…”