“…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).…”