Mineralogical composition and microalgae communities of solar salt tumuli from Tuticorin, Southeast coast of India

Abstract

The present work deals with the microbial population and mineralogical composition of solar salt pan tumuli (gypsum crust). Tumuli containing multicolor layered microbial communities develop in the crystallizer ponds of commercial salterns. The upper crust is densely populated by orange unicellular cyanobacteria. Below is a layer of green- colored filamentous cyanobacteria. <em>Bacillariophyta </em> and <em>Chlorophyta </em> groups are also identified microscopically. X-ray powder diffractometer (XRD) patterns and the intensity peaks observed in tumuli indicated the predominance of gypsum, calcite and halite along with other associated minor minerals viz; quartz, chlorite, kaolinite, ilmenite and illite are confirmed by Fourier transform infrared spectroscopy (FTIR). The scanning electron microscopic (SEM) analysis of tumuli was also carried. Associated occurrence of mineralogical composition and microbial communities are highlighted and investigated.