01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-03-0219 |
| Title of Abstract | Seasonal Dynamics of Inorganic Macronutrients in the Coastal Waters off Paradip, Bay of Bengal |
| Authors | Alok Sethi*, Sumit K. Mohanty, Suchismita Sahu, Susmita Raulo, Baisakhi Pattnaik, Suchismita Srichandan, Sanjiba K. Baliarsingh, Kamal K. Barik, Alakes Samanta, Pratap K. Chhotaray |
| Organisation | Centurion University of Technology and Management, Bhubaneswar-75 |
| Address | Patrapada Bhubaneswar, Odisha, India Pincode: 751019 E-mail: sethialok27@gmail.com |
| Country | India |
| Presentation | Oral |
| Abstract | This study examines the seasonal and spatial patterns of key inorganic macronutrients, as well as their stoichiometry in the coastal waters off Paradip, western Bay of Bengal. Sampling was conducted across three stations during post-monsoon, pre-monsoon, and monsoon seasons between January 2024 and July 2025 to assess nutrient fluxes, limitation patterns, and implications for primary productivity. Nitrate and nitrite concentrations peaked during the monsoon, driven by enhanced riverine discharge, whereas pre-monsoon values were minimal due to phytoplankton uptake. Ammonium exhibited elevated concentrations in the post-monsoon, linked to organic matter decomposition, but remained low during pre-monsoon. Phosphate followed a contrasting pattern, with high monsoonal levels from agricultural runoff and minimal pre-monsoon concentrations, while post-monsoon subsurface maxima suggested regeneration from sinking detritus. Silicate concentrations were markedly high during the monsoon, reflecting terrestrial input, and depleted during dry seasons due to diatom uptake. Nutrient stoichiometry revealed strong seasonal shifts: phosphorus limitation dominated offshore during pre- and monsoon periods, silicate limitation prevailed in post-monsoon surface waters, and nitrogen limitation emerged nearshore in pre-monsoon. Chlorophyll-a distribution further reflected these dynamics, with post-monsoon higher magnitude linked to favourable nutrient ratios, while monsoon phytoplankton growth was restricted by light limitation despite nutrient enrichment. Overall, the outcomes highlight the interplay of hydrological forcing, nutrient regeneration, and stoichiometric balance in regulating primary productivity and ecosystem functioning in this dynamic coastal system. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Nutrient Stoichiometry; Monsoon; Phytoplankton; Chlorophyll-a; Mahanadi |
| For Awards | yes |
| Date Of Birth | 06-02-2002 |
| ECSN Registration Number | IIOE2-ECSN-0145 |