Performance of an Agricultural Wetland-Reservoir-Irrigation Management System

Abstract

Constructed wetlands (CW) have gained recognition as a management option for the treatment of various agricultural wastewaters. This study involved the design, construction, and initial evaluation of a wetland-reservoir-irrigation (WRI) system. The system was established in Truro, Nova Scotia, Canada, with the goal to capture, treat, and re-use agricultural sub-surface drainage water. It consisted of a 1.8-ha area of a cropped field that was systematically tile drained. Drainage water was directed through a 2-cell CW and then into a reservoir-irrigation pond. Flow rate hydraulics, residence time distributions, and treatment efficiencies for nitrate-nitrogen (NO 3 − -N) and Escherichia coli (E. coli) were monitored for 14 months. Mass reductions of NO 3 − -N and E. coli from the CW were 67.6% and 63.3%, respectively. However, average E. coli concentrations increased to 178 CFU 100 mL −1 in the reservoir during the warm season. It may therefore be best to use reservoir water for irrigation of crops that are not consumed raw. To aid in the future design of similar systems, mean first-order rate constants (k s ) for NO 3 − -N and E. coli were calculated to be 8.0 and 6.4 m y −1 , respectively. The volume of water collected in the reservoir exceeded typical irrigation requirements of the drained land and could therefore provide irrigation to additional land beyond the drainage area.

Performance of a full scale constructed wetland as ecological practice for agricultural drainage water treatment in Northern Italy

“…If single years are analysed, the retention was only 40% in 2018. This value was lower than 68% reported by Haverstock et al (2017), most probably due to the lower HRT. In fact, the average HRT during the Event 1, that represented 76% of the total yearly inflow, was 6.6 days (Table 3), while for the system studied by Haverstock et al it was 15 days.…”

“…Like other types of naturebased solutions, SFCWs used for agricultural drainage water treatment are being used at different scales, for different catchments and in different climates, and that makes comparison among them rather difficult. In this study, the average water inflow (61 m 3 day -1 in 2018 and 27 m 3 day -1 in 2019) was much lower than the one given by Dal Ferro et al (2018) for a SFCW in the Veneto region (Italy) that approximately amounted to 5,480 m 3 day -1 , but was also much higher than 17 m 3 day -1 for a Canadian SFCW studied by Haverstock et al (2017).…”

“…Nevertheless, the agricultural drainage water can be a source of diffuse pollution in aquatic ecosystems due to high concentrations of nitrate, certain salts, phosphorus, organic nitrogen, pesticides and sediments (Woltemade, 2000;Haverstock et al 2017), as confirmed by the authors from different parts of the world (Tanner and Kadlec, 2013;Darwiche-Criado et al 2017;Mendes et al 2018a;Song et al 2019). Particularly, P enrichment in runoff leads to eutrophication harmful to plants growth (Johannesson et al 2017;Lavrnić et al 2018), and it can even result in toxic algae blooms and loss of biodiversity (Reinhardt et al 2005).…”

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...…”

Distribution and Driving Factors of Forest Swamp Conversions in a Cold Temperate Region

“…Our result found that hydrologic, human, and climatic factors accounted for conversions to farmland appropriately. Sufficient hydrologic conditions provided water protection for agricultural irrigation and plant growth [ 100 , 101 ]. The higher temperature in the south promoted the evaporation of swamps water and provided proper climatic conditions for crop growth in cold temperature regions [ 23 ].…”