Physico-Chemical and Biological Environment of the Abandoned Coal Quarries for Possibility of Fish Culture

Coal quarry is the abandoned mines surface pit after mining of the coal. There are number of such surface pit available in Jharkhand. These surface pits are filled with rain water and remain fallow. Some coal quarries water is used for irrigation and non-domestic purposes. The present work was to study the Physico-chemical and biological parameters of the coal quarries to study the possibilities of fish culture in these surface pits. The analysis of four coal quarries has been done from 2008 to 2010. The findings revealed that Physico-chemical parameters are within favorable range of fish culture except the low alkalinity and poor concentration of plankton (natural food of fish). The heavy metals were present in sediment, water, plankton and fish muscle. The heavy metals i.e. iron, cobalt, nickel, copper, zinc, manganese, cadmium, lead and mercury is present sediment, water, plankton and fish muscle. The abundance order of metals were Fe > Zn > Pb > Mn > Cu > Ni > Co > Cd > Hg in sediment and Fe > Zn > Mn > Cu > Pb > Ni > Cd > Co > Hg in water, Zn > Pb > Cu > Ni > Fe. Mn > Pb > Co > Hg in plankton and Fe > Zn > Mn > Pb > Ni > Cu > Co > Hg > Cd in fish muscle the concentration of heavy metals are sediment > water > fish muscle > plankton. The heavy metals in water were below the maximum permissible level of drinking water but it was more than the concentration of heavy metal for continuous exposure of the fish. The fish analyzed for heavy metals was young wild fish. When the coal quarry was stocked with cultivable varieties there was poor survivability. As per the above finding it has been found that there is need of further study for selection of fish varieties, culture practices, biological method to reduce the heavy metals, harvesting methods and to decide the safest age of the fish for the consumption.