Pardis Fazli

Decadal Variation of Nutrient Level in Two Major Estuaries in Indian Sundarbans

The impact of the nutrient level on the water quality in the Hooghly and Matla estuarine complex in Indian Sundarbans was assessed for three decades (1984-2014). Nitrate, phosphate and silicate were used as indicators of nutrient related water quality in the estuarine water. Our first order analysis reflects significant spatio-temporal variations of selected nutrients with relatively higher values in the Hooghly estuary (in the western Indian Sundarbans) compared to the Matla estuary (in the central Indian Sundarbans). Significant variations were observed in dissolved nitrate, phosphate and silicate concentrations between stations and years (p < 0.01). Such pronounced variations may be attributed to the location of highly industrialized and urbanized city of Kolkata, Howrah and Haldia port-cum-industrial complex adjacent to the Hooghly estuary. The sudden rise of selected nutrients during premonsoon, 2009 (irrespective of sampling stations) is directly related to AILA, a super-cyclone that occurred in the lower Gangetic delta during 22nd 25th May, 2009.

Mangrove Health Card: A Case Study on Indian Sundarbans

Relative abundance and Shannon-Weiner species diversity index of true mangrove species were estimated in 10 sampling stations of Indian Sundarbans during 2013. The mangrove patches in the selected stations were categorized into a 4-point scale depending on the values of Shannon-Weiner species diversity index. The health of the mangrove forest as per our constructed 4-point scale was found to be regulated primarily by anthropogenic factors, although in station like Sagar South, the natural erosion may be the key player in determining the mangrove floral diversity.