Evaluation of the Efficiency of Duckweed (Lemna minor L.) as a Phytoremediation Agent in Wastewater Treatment in Kashmir Himalayas

Abstract

In the present study, the efficiency of duckweed (Lemna minor L.) as an effective natural biological tool in wastewater treatment was examined in an outdoor aquatic system. Duckweed plants were inoculated into wastewater and tap water systems for treatment over fifteen day's retention periods under local outdoor natural conditions. Water samples were taken below duckweed cover after fifteen days to assess the plant's efficiency in purifying waste water from different pollutants. For comparison, the plants were also grown in tubs containing tap water. The results show that concentrations of Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), Copper (Cu), Zinc (Zn), Nickel (Ni), Chromium (Cr), Cadmium (Cd) and Lead (Pb) decreased by 93. 4%, 99.9%, 93.9%, 98.5%., 91.9%, 85.0%, 95.0%, 90.0%, 99.8%, 99.5% and 95.0% respectively in waste water and subsequently these elements exhibited an increasing concentration in the plant body. Almost similar results were obtained when the plants were grown in tubs containing tap water. Biochemical parameters viz. chl-a, b, total-chl, carbohydrates and proteins as well as nutrient status of the macrophyte increased after the completion of the retention period both in waste and tap water. Results confirm that duckweeds can effectively be used for wastewater treatment systems.

Performance assessment of local aquatic macrophytes for domestic wastewater treatment in Nigerian communities: A review

“…The capacities of these three free-floating aquatic macrophytes in removing heavy metals are shown in Table 1. Over the past decade, Sources: (Srivastava et al, 2008;Swarnalatha and Radhakrishnan, 2015;Showqi et al, 2017, Rai, 2019. NB: Bold* ¼ selected aquatic macrophytes.…”

Kettle holes reflect the biogeochemical characteristics of their catchment area and the intensity of the element-specific input

“…Some Lemna spp. were found to remove N, P, K, Mg, and Ca from wastewater (Patel and Kanungo 2010;Showqi et al 2017). If we apply elemental concentrations previously determined in Lemna dry weight (Balasubramanian and Kasturi Bai 1992), the area of floating duckweed (Lemna minor, Spirodela polyrhiza) of the water surface in June, and the biomass of duckweed (Kazanjian et al 2018), then the amount of Ca, K and P present in duckweed was about 40 times higher in RG than in KR (Table S2).…”

Perspectives on utilization of macrophytes as feed ingredient for fish in future aquaculture

“…Duckweeds, as a natural protein source, are rich in essential amino acids among most other plant proteins (Kabir et al 2009) and nearly resemble the protein of animal origin (Hillman & Culley 1978;Journey et al 1991;Bairagi et al 2002;Yilmaz et al 2004;Aslam et al 2016;Asimi et al 2018). It has a merit over other protein sources as these are characterized by better availability and absorption of amino acids, including lysine and methionine (Cruz et al 2011;Cruz et al 2015), as well as of vitamins A, B and E and carotenoids (Chojnacka, 2006;Showqi et al 2017). The duckweeds are reported to possess 39.20% essential, 53.64% nonessential and 7.13% non-proteinogenic amino acids (Chakrabarti et al 2018).…”

“…2015), as well as of vitamins A, B and E and carotenoids (Chojnacka, 2006; Showqi et al . 2017). The duckweeds are reported to possess 39.20% essential, 53.64% non‐essential and 7.13% non‐proteinogenic amino acids (Chakrabarti et al .…”