Effects of open water on the performance of a constructed wetland for nonpoint source pollution control

Abstract

The seasonal performance of four differently configured constructed wetland systems was compared for the treatment efficiency of nonpoint source pollution. Dead plants in the constructed wetlands increased the nitrogen removal rate during winter by providing organic carbon, which is essential for the denitrification process. However, when the wetlands released phosphorus from the dead plants, the removal rate of phosphorus decreased. After seven growing seasons, plant coverage was nearly 100%, and the dissolved oxygen (DO) concentration was lowered to 1.3-5.4 mg/L. Open-water sections were then constructed inside the wetlands, which resulted in enhanced DO concentrations as well as improved treatment efficiency of nutrients and biochemical oxygen demand (BOD). Overall, performance of the constructed wetland was improved BOD, total nitrogen, and total phosphorus with the establishment of open water sections in the constructed wetland system.

Constructed Wetlands for Water Quality Improvement: A Synthesis on Nutrient Reduction from Agricultural Effluents

“…Constructed wetlands have been used to improve water quality delivered from cropland via two predominant pathways: surface flows (e.g., precipitation-driven runoff or irrigation tailwaters) or subsurface drainage (e.g., tile drainage). Table 1 summarizes the data compiled from 39 scholarly papers (28 surface-flow influent sources and 11 subsurface drainage influent sources), representing studies conducted on three continents (North America, Europe, Asia) and published between the years 2000 and 2019 (Bass, 2000;Beutel et al, 2014;Blankenberg et al, 2016;Borin and Tocchetto, 2007;Braskerud, 2002;Chen et al, 2015;Díaz et al, 2012;Dunne et al, 2015;Fink and Mitsch, 2004;Goddard and Elder, 1997;Gu, 2008;Han et al, 2017;Haverstock et al, 2017;Hoagland et al, 2001;Hoffmann et al, 2012;Juston and DeBusk, 2006;Kasak et al, 2018;Kim et al, 2010;Koskiaho et al, 2003;Kovacic et al, 2000Kovacic et al, , 2006Larson et al, 2000;Lavrnić et al, 2018;Lentz et al, 2014;Liikanen et al, 2004;Lu et al, 2009;Ludwig, 2010;Maniquiz et al, 2012;Maxwell et al, 2017;Miller et al, 2002;Moreno-Mateos et al, 2009;Mustafa et al, 2009;Pietro and Ivanoff, 2015;Poe et al, 2003;Rei...…”

A Topography Analysis Incorporated Optimization Method for the Selection and Placement of Best Management Practices

“…Among those listed, wetlands and detention ponds were the most preferred BMPs in all cases. Many studies have described detention ponds and wetlands as permanent pools that are effective in reducing peak flow and trapping NPS pollutants [16], [53], [54]. As shown in Fig.…”