Selection of Suitable Plant Species in Semi Arid Climatic Conditions for Quality Improvement of Secondary Treated Effluent by Using Vertical Constructed Wetland

摘要

The wetland plant species play a critical role in determining the performance of the wetland systems. Thus selection of suitable plant species for vegetation in treatment wetland units is of great importance to enhance the efficiency of the system. The present research aims to identify the suitable plant species for constructed wetlands in the semi-arid climate of Rajasthan (India). The performance of the two widely used Indian wetland plants, Phragmitis australis and Canna Mica were evaluated in vertical up-flow constructed wetland using secondary treated effluents. Performance efficiency of both the plant species was evaluated fa physico-chemical and microbial contaminants removal. The proposed study highlights the comparative as well as significant suitability of Canna indica plantation over the Phragmitis australis under semi-arid climatic conditions. The unit planted with Canna indica showed 39.7 and 50.9% removal for total Kjeldahl nitrogen (TKN) and ammonia-nitrogen respectively. Nitrate nitrogen in the treated effluents has a significant increment of 3.8 times higher than influents. Importantly, the indicator organism coliform reduction was observed as 1.87 log (MPN/100mL) in the effluent of Canna indica planted unit as against 1.01 log (MPN/100mL) in the effluent of Phragmitis australis planted wetland.