Study on littoral zone sediment quality and aquatic Macrophyte diversity of opencast coal pit-lakes in Raniganj coal field, West Bengal, India

摘要

Littoral zone sediment quality and species diversity of aquatic macrophytes were studied in four opencast coal pit-lakes at Raniganj Coalfield areas. Quantitative estimation of different soil parameters revealed that pH was neutral to low alkaline (7.00 to 8.90), conductivity, 130 to 670 μS/cm, available nitrogen, 22.0 to 194 kg/ha, available phosphorus, 2.04 to 27.1 kg/ha, available potassium, 85.5 to 424 kg/ha and organic carbon content was varied from 0.096 to 2.83 %. Distribution and concentration of heavy metals in the sediments were recorded as, Pb (0.033 to 1.57 mg/kg), Cd (0.018 to 0.108 mg/kg), Cr (non-detectable to 0.022 mg/kg) and As (non-detectable level). Aquatic macrophyte community was enriched by the most predominant nine species, viz ., Potamogeton malainus , Ipomoea fistulosa , Typha angustifolia , Alternanthera philoxeroides , Valliseneria spiralis , Hydrilla verticillata , Marsilea minuta , Nymphoides indica and Nymphaea nouchali . The main objective of this work is to create a concrete baseline data of the water quality and soil parameters of the pit-lakes in the RCF areas. This work has been able to establish a relationship between the sediment properties, nutrient availability and growth of the macrophytes with different species composition.