ABSTRACT
Manipur, a state in north-east India in the eastern Himalayas, has a rich and diverse heritage of wetlands (Jain et al., 2011). The wetlands of Manipur cover 524.5 km2 and account for 2.4% of the total geographical area (Singh and Singh, 1994). Loktak (93°46′ E to 93°55′ E, and 24°22′ N to 24°42′ N), a Ramsar site covering an area of 287 km2, is the largest natural freshwater wetland in the State of Manipur (Figure 16.1) and north-east India (Trishal and Manihar, 2002). Currently, Loktak is marked by nutrient enrichment, heavy metal pollution, loss of biodiversity, a high rate of siltation and garbage dumping (Meitei and Prasad, 2015), and an alarming proliferation of floating phoomdi covering more than 50% of the wetland (Trishal and Manihar, 2002). The unmanaged phoomdi accelerates the ecological succession of Loktak from open water to marshes and swamps. Phoomdi is a heterogenous mass of soil, vegetation, and organic matter in different stages of decay that floats in the wetland (Meitei and Prasad, 2013). Hence, to tackle the problem with phoomdi, the Loktak Development Authority (LDA) has been relentlessly searching for ways to clean phoomdi from Loktak (LDA, 2011). Recent reports suggest the conversion of phoomdi biomass into compost and its use in agriculture (Singh et al., 2014; Singh and Kalamdhad, 2014). In this chapter, the speciation and fate of various heavy metals from phoomdi compost are discussed, with an emphasis on the possible risks of heavy metal bioavailability from phoomdi. Geographic location of Loktak Lake, Manipur, north-east India. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315372952/55acbd01-4a7c-4b6c-99dc-d931a043bf8c/content/fig16_1_B.jpg" xmlns:xlink="https://www.w3.org/1999/xlink"/>
