01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-03-0257 |
| Title of Abstract | Influence of Hydrographic Forcing on Phytoplankton Morphology and Community Structure along the Central West Coast of India |
| Authors | Shiva Singh*, Karnan Chinnadurai, Aswathy S, Abhiram KP, Biraja K Sahu |
| Organisation | CSIR-National Institute of Oceanography |
| Address | Room no- SR-3, NIO colony, Dona Paula Panjim, Goa, India Pincode: 403004 E-mail: shiva03095@gmail.com |
| Country | India |
| Presentation | Poster |
| Abstract | This study investigates the relationship between environmental parameters and the abundance and morphology of phytoplankton along the central west coast of India. Monthly samplings were conducted over six months (December 2023; January-April 2024; and September 2024) from multiple coastal stations with discrete depth sampling. Regarding phytoplankton shape, a total of 18 classes were identified (based on taxonomic data) and grouped into two categories as simple and complex. The simple category consisted of a single basic geometry, whereas the complex category was formed by a combination of two or more basic geometries. The analysis revealed that complex morphological shapes were more prevalent under low-salinity conditions, with their abundance increasing notably during periods influenced by monsoonal rainfall and river influx. The dominant shapes found were Prism on elliptic base girdle view (eg: Chaetoceros sp., Eucampia sp.), Cylinder + 2 half spheres (eg: Skeletonema sp.), Prism on parallelogram base (eg: Nitzschia sp., Pseudonitzschia sp., Pleurosigma sp.). The seasonal trend was also observed among the complex shapes, decreasing from north-east monsoon (174255 ± 85199 cells/L) to pre-monsoon (60750 ± 48649 cells/L) and again increased during south west monsoon (508684 ± 42979 cells/L). Irrespective of seasons, among the simple shapes, centric diatoms accounted for 75.1% and pennate diatoms for 24.8%, whereas in the complex shapes, centric diatoms comprised 82.9% and pennate diatoms 17.1%. Additionally, complex morphological shapes showed a strong negative correlation with salinity (n = 90; r = ⿿0.76, p < 0.001), indicating a greater affinity for low-salinity waters. The total abundance was largely contributed by complex-shaped phytoplankton, suggesting that these taxa dominate bloom conditions under reduced salinity regimes. Our study shows the combined influence of hydrographic forcing and morphological traits in shaping phytoplankton community structure in coastal water. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Phytoplankton morphology, Centric diatoms, Complex shapes, Salinity, Monsoon |
| For Awards | yes |
| Date Of Birth | 30-09-1995 |
| ECSN Registration Number | IIOE2-ECSN-0158 |