Effect of loading rate and planting on treatment of dairy farm wastewaters in constructed wetlands—II. Removal of nitrogen and phosphorus

Assessment of the Efficiency of a Pilot Constructed Wetland on the Remediation of Water Quality; Case Study of Litani River, Lebanon

“…Such improvement in water quality can be at least partially attributed to the utilization of the planted macrophytes which have been shown by numerous studies to be highly efficient in the uptake of nutrients during their growth period, and to have a positive correlation between biomass production and nutrient uptake [20][21][22][23][24]. And, wetlands containing such types of plants remove larger quantities of nitrate than unplanted wetlands [25][26][27][28]. Contrary to terrestrial plants, a vast majority of aquatic plants are also shown to have a substantial ammonium preference which is consistent with the highest drop in the ammonia level (93.30%) in this study [2].…”

Recovery of dairy manure nutrients by benthic freshwater algae

“…Several possibilities exist for replacing conventional cropping for nutrient recovery with aquatic-based cropping systems, including the use of wetlands (Tanner et al, 1995), water hyacinths (Costa et al, 2000), duckweed (Bonomo et al, 1997), high-rate algal ponds (Fallowfield et al, 1992), and cyanobacteria Lincoln et al, 1993). There is a considerable literature on the treatment of municipal wastewater in high-rate ponds (Nurdogan and Oswald, 1995) and on the treatment of dairy and swine manures by monoalgal cultures such as Spirulina (Lincoln and Wilkie, 1995;Lincoln et al, 1996;Olguin et al, 1997).…”

Water and sediment chemistry of a wetland treating municipal wastewater

“…However, stored P is released when the input of phosphate with waste water exceeds the storage potential of the soil (Kadlec & Knight 1996), and P in effluent outflow has been shown to increase after passage through land treatment facilities, because of release of P from P-rich sediments that had accumulated over the years (Nichols 1983). Tanner et al (1995b) also showed that a shorter retention time results in a lower removal rate.…”

“…Most published studies actually deal with constructed wetlands (e.g., Bhamidimarri et al 1991;Tanner et al 1995aTanner et al ,b, 1998Nguyen et al 1997). Furthermore, most studies have concentrated on the removal of nitrogen and phosphorus (e.g., Cooke et al 1990;Cooke 1992;Tanner et al 1995bTanner et al , 1998Nguyen et al 1997), whereas only the recent work reported in Chague-Goff et al (1999) deals with the removal of heavy metals.…”

“…The low efficiency can be attributed to the short retention time in the system. Previous studies have shown that a retention time of at least 5 days is required for the nitrification process (Hammer 1989), and that an increased retention time improves the efficiency of the system for NH 4 -N removal (Tanner et al 1995b). The retention time of effluent is probably less than a day in the Turangi confined wetland.…”