Carty, Spring M. (2002) An experimental study of the effectiveness of four wetland plant species for wastewater treatment. MSc thesis, University of Akron, Ohio (Fraser)

ABSTRACT

   The purpose of this study was to answer two questions: (1) are certain plants more efficient at treating wastewater and (2) do combinations of plants enhance treatment?  The experimental design entailed two experiments; a microcosm study with low and high nutrient inputs and field data collected from in use domestic treatment wetland systems in Northwest Ohio.  Water quality analysis of the microcosm study showed that unvegetated microcosms performed significantly poorer than vegetated microcosms for the treatment of total nitrogen and total phosphorus, p < 0.05.  Also, Phalaris arundinaceae performed significantly poorer on most sampling dates compared to the other three species Scirpus validus, Carex lacustris and Typha latifolia, p < 0.05.  The range of total nitrogen for low fertility was 5 mg/L (Carex lacustris) -17 mg/ L (unvegetated); high fertility was 7 mg/L (Typha latifolia) – 38 mg/L (unvegetated).  The range of total phosphorus for low fertility microcosms was 2 mg/L (combination) – 10 mg/L (unvegetated); high fertility was 4 mg/L (Phalaris arundinaceae) – 10 mg/L (unvegetated).  Fertility level effected relative phytoremediation, however it had no significant effect on species growth, except within the combination microcosms.  Typha latifolia had a significantly higher biomass, p < 0.05, in the low fertility microcosms.  Biomass showed no correlation with respect to treatment capabilities, in either of the two studies.  More data is needed to draw any significant conclusions from the treatment wetland systems in Northwest Ohio.

Full Thesis on file at UA.