Environmental parameters and nutrient concentrations of marine water, Matla River and Thakuran River of Maipith coastal areas in the Indian Sundarban mangroves areas

Physiochemical parameters (salinity and pH) of the each 18 collected samples were measured using the Eureka 2 Manta multiprobe (Eureka Environmental Engineering, Texas, USA) at ZMT. The inorganic nutrient that includes the combined nitrate and nitrite (NOx), phosphate (PO4), silicate (Si), total organic carbon (TOC) and total nitrogen (TN) were analyzed in this investigation. Total 50mL of each sample was filtered through a 0.7μm syringe filter and poisoned with 200μL of a 3.5 g/100mL HgCl2 solution for further analysis using a continuous flow analyzer (Flowsys by Unity Scientific, Brookfield, USA). For measurements of total organic carbon (TOC), 30mL samples were filtered through 0.45μm pore GF/F filters (Whatman GF/F, GE Healthcare, Pittsburgh, USA) followed by acidification with concentrated HCl (pH below 2) and analyzed by high-temperature oxic combustion (HTOC) method using a TOC-VCPH TOC analyzer (Shimadzu, Mandel, Canada). Seawater standards (Hansell laboratory, RSMAS University Miami, USA) for calibration and quality control artificial and ultrapure water as blanks were used.