Wastewater Management Using an Aquatic and Semi-aquatic Plant species, Cattail (Typha domingensis) and Duckweed (Spirodela polyrhiza L.)
C. A. Byrne
Department of Biology, University of Guyana, Georgetown, Guyana
A. Nankishore
Department of Biology, University of Guyana, Georgetown, Guyana
A. A. Ansari *
Department of Biology, University of Guyana, Georgetown, Guyana.
*Author to whom correspondence should be addressed.
Abstract
Constructed wetlands are excellent chemical-free system, for reducing physico-chemical parameters and faecal coliform densities. Present research work was carried from 2013 to 2014 with the objective of wastewater management using two plant species cattail (Typha domingensis) and duckweed (Spirodela polyrhiza L.), singly and in combination. The results indicated that parameters such as NH3+, DO, pH and turbidity, decreased in effluent from wetland containing cattails, duckweeds and both in combination. Other parameters such as EC, K, P, Cl and Na increased in effluent from one or more wetland trials. Faecal coliform reduction close to 47% was also noted. Absorption and uptake, by plants and microorganisms, appears to be the primary mechanism for nutrient removal, while parameters such as P, SO42- and Fe are removed through formation of bonds with particles in the soil. The study revealed wetlands containing both floating and emergent macrophytes play significant role in improving wastewater quality.
Keywords: Constructed wetlands, cattails, domestic wastewater, duckweed, effluent, influent, pollution