Spring inter monsoon algal blooms in the Eastern Arabian sea: Shallow marine encounter off Karwar and Kumbla Coast using a Hyperspectral radiometer

We encountered the presence of algal blooms in the shallow coastal waters; typical of case II conditions off Karwar (Karnataka) and Kumbla (Kerala), eastern Arabian Sea during the Inter Monsoon. The algal blooms are Trichodesmium species and appear in shades of brown strands and tufts representing T. Erythraeum. Sites of the algal blooms depict a high spectrophotometric surface chlorophyll-a value ranging from 32- 39 mgm-3 and sea surface area surrounding the bloom sites depict lower values of chlorophyll-a (1-3 mgm-3). In-situ Hyperspectral radiometer measurements depict the existence of Chlorophyll Maxima at various depths (3.0-37.31 ug/l) representing the blooms along with their surface appearance. Contrary to the Karwar blooms that are dense, the blooms at Kumbla were dispersed and scantly distributed on the surface waters. Our sea-truth data on mean Sea Surface Temperature of Karwar (30.61 °C) that simulates the Kumbla (30.34 °C) scenario and the mean salinity of Kumbla was 35.86psu, and that of Karwar that is slightly elevated (35.40psu), suggests that SST and salinity probably do not either directly enhance or provide an environment for the eterioration of algal blooms

Heterogeneous microbial oceanographic environments: Application of GIS technology in deciphering of microenvironment scenarios off the central west coast of India

In the vast oceanic microbial environment of 2468.83km 2, GIS modeling techniques involving sixty query steps, enabled the deciphering of Microenvironments as low as 1.19km 2 to 38.6 km 2 for the summer of 2004 and in case of summer 2005 where 84 query steps were involved to decipher Microenvironments of 10.55km 2 to 25.94km 2. Thirtythree sampling stations were established between Betul to Ankola off the central west coast of India accounting for a spatial coverage of 2468.83km 2. GIS query-modeling investigation was carried out using spatial layers of depth, optical parameters (k-Irradiance attenuation Coefficient, c-Beam attenuation coefficient), sediment size parameters (Sediment Mean Size and Sediment Sorting) and Benthic Foraminifera Suborders (Rotaliina, Textulariina, Miliolina, Lagenina). Foraminifera have been used as a surrogate parameter. However, any microbial parameter could proxy for foraminifers providing for the numerical deciphering of microenvironments. This is suggestive of the assimilation of GIS technology for a better appreciation of microbial oceanography