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Journal of Coastal Conservation

, Volume 21, Issue 1, pp 233–244 | Cite as

Suspended sediment dynamics in Cochin estuary, West Coast, India

Article

Abstract

An observational study was conducted in Cochin estuary to examine the relative impacts of tidal and river runoff forcing upon suspended sediment dynamics at different time scales. Time series measurements of salinity and suspended sediment concentration (SSC) were conducted at spring and neap periods of wet and dry seasons. These data were complemented by measurements of tides, currents, vertical profiling of hydrography and turbidity at the main inlet of the estuary. The results showed that SSC was maximum at the main inlet and decreased towards upstream for both seasons. The intra-tidal variations of water column stability suggested that prominent stratification occurred at the main inlet as a result of torrential rain during spring tides of wet season. During neap tides of wet season, the runoff was relatively lower and intense turbulent mixing occurred during the ebb. During dry season, well-mixed (spring) and partially stratified (neap) conditions were noticed. Suspended sediment fluxes were also analyzed using the decomposition method to identify mechanisms of turbidity maintenance at the inlet. The fluxes were dominated by an advective component during both tidal phases of wet season and dry-neap period. In contrast, the tidal pumping was the main contributing process for residual fluxes during the dry-spring period. The residual sediment transport at the inlet was directed outward irrespective of tidal ranges and seasons due to the strong ebb currents with longer duration. These findings are significant for the development and protection of harbors situated close to the inlet in estuaries and for the efficient implementation of an integrated coastal management system.

Keywords

Ebb currents Stratification Velocity Temporal variations Tides Sediment fluxes 

Notes

Acknowledgements

Authors are thankful to the Director, CSIR-NIO and Scientist In-Charge, Regional Centre, Kochi for their keen encouragement and support. The study forms a part of the project “Ecosystem modeling of Cochin backwaters” funded by Integrated Coastal and Marine Area Management (ICMAM-PD), Ministry of Earth Sciences, Chennai. We extend our thanks to the staff and research students of NIO for their valuable assistance during field collections. This paper work is a part of the doctoral research of the first author, Vinita J. who acknowledges the Council of Scientific and Industrial Research, New Delhi, for the financial support in the form of senior research fellowship. This is NIO Contribution.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Human and animal rights and informed consent

This article does not contain any studies with human participants or animals performed by any of the authors.

References

  1. Akhil PS, Sujatha CH (2014) Spatial budgetary evaluation of organochlorine contaminants in the sediments of cochin estuary, India. Mar Pollut Bull 78(1–2):246–251. doi: 10.1016/j.marpolbul.2013.10.021 CrossRefGoogle Scholar
  2. Aravind NP, Sheeba P, Nair KKC, Achuthankutty CT (2007) Life history and population dynamics of an estuarine amphipod- Eriopisa Chilkensis Chilton (Gammaridae). Estuar Coast Shelf Sci 74:87–95CrossRefGoogle Scholar
  3. Arun AU (2005) Impact of artificial structure on biodiversity of estuaries: a case study from cochin estuary with emphasis on clam beds. Appl Ecol Env Res 4:99–110CrossRefGoogle Scholar
  4. Balachandran KK (2001) Chemical oceanographic studies of the coastal waters of Cochin. Ph.D thesis, Cochin University of Science and Technology, Cochin, pp. 148Google Scholar
  5. Balachandran KK, Laluraj CM, Nair M, Joseph T, Sheeba P, Venugopal P (2005) Heavy metal accumulation in a flow restricted tropical estuary. Estuar Coast Shelf Sci 65:361–370. doi: 10.1016/j.ecss.2005.06.013 CrossRefGoogle Scholar
  6. Balachandran KK, Laluraj CM, Martin GD, Srinivas K, Venugopal P (2006) Environmental analysis of heavy metal deposition in a flow-restricted tropical estuary and its adjacent shelf. Environ Forensic 7:345–351CrossRefGoogle Scholar
  7. Balachandran KK, Reddy GS, Revichandran C, Srinivas K, Vijayan PR, Thottam TJ (2008) Modelling of tidal hydrodynamics for a tropical ecosystem with implications for pollutant dispersion (cochin estuary, Southwest India). Ocean Dynam 58:259–273CrossRefGoogle Scholar
  8. Balchand AN, Rasheed K (2000) Assessment of short term environmental impacts on dredging in a tropical estuary. Terra et Aqua 79Google Scholar
  9. Bindu KR, Deepulal PM, Gireeshkumar TR, Chandramohanakumar N (2015) Evaluation of heavy metal enrichment in cochin estuary and its adjacent coast: multivariate statistical approach. Environ Monit Assess 187:519CrossRefGoogle Scholar
  10. Bruun P, Gerritsen F (1960) Stability of coastal inlets. North-Holland Publishing Co., AmsterdamGoogle Scholar
  11. Chandramohan PV (1989) Density currents and siltation-with particular reference to cochin. Dissertation, Delft Hydraulics Laboratory, The NetherlandsGoogle Scholar
  12. Cochin Outer Harbor Project (2010) Retrieved from http://cochinport.gov.in/
  13. de Nijs MAJ, Winterwerp JC, Pietrzak JD (2009) On harbor siltation in the fresh-salt water mixing region. Cont Shelf Res 29:175–193CrossRefGoogle Scholar
  14. de Nijs MAJ, Winterwerp JC, Pietrzak JD (2010) The effects of the internal flow structure on SPM entrapment in the Rotterdam waterway. J Phys Oceanogr 40:2357–2380CrossRefGoogle Scholar
  15. Dronkers J (1986) Tidal asymmetry and estuarine morphology. Neth J Sea Res 20:117–131CrossRefGoogle Scholar
  16. Dyer KR (1997) Partially mixed and well-mixed estuaries. In: Estuaries––a physical introduction, 2nd edition, eds. John Wiley and Sons, p 136–164Google Scholar
  17. Dyer KR, New AL (1986) Intermittency in estuarine mixing. In: Wolfe DA (ed) Estuarine variability. Academic press, p 321–339 View at Google ScholarGoogle Scholar
  18. Erikson LH, Wright SA, Elias E, Hanes DM, Schoellhamer DH, Largier J (2013) The use of modeling and suspended sediment concentration measurements for quantifying net suspended sediment transport through a large tidally dominated inlet. Mar Geol 345:96–112CrossRefGoogle Scholar
  19. French JR, Burningham H, Benson T (2008) Tidal and meterological forcing of suspended sediment flux in a muddy mesotidal estuary. Estuar Coast 31:843–859CrossRefGoogle Scholar
  20. Ganju NK, Schoellhamer DH (2006) Annual sediment flux estimates in a tidal strait using surrogate measurements. Estuar Coast Shelf Sci 69:165–178CrossRefGoogle Scholar
  21. Gopalan UK, Doyil T, Vengayil P, Udaya V, Krishnakutty M (1983) The shrinking backwaters of Kerala. J Mar Biol Ass India 25:131–141Google Scholar
  22. Gopinathan CK, Qasim CZ (1971) Silting in navigational channels of cochin harbor area. J Mar Biol Ass India 13:14–26Google Scholar
  23. Lallu KR, Fausia KH, Vinita J, Balachandran KK, Naveen Kumar KR (2014) Transport of dissolved nutrients and chlorophyll a in a tropical estuary, southwest coast of India. Environ Monit Assess. doi: 10.1007/s10661-014-3741-6 Google Scholar
  24. Laxmilatha P, Appukuttan KK (2002) A review of the black clam (Villorita cyprinoides) fishery of the Vembanad Lake. Indian J Fish 49(1):85–92Google Scholar
  25. Maggi F (2005) Flocculation dynamics of cohesive sediment. PhD-Thesis, Delft University of Technology, Delft, 136Google Scholar
  26. Mathew TK, Chandramohan PV (1989) Implications of nautical depth at Cochin. In: Proc. 3rd Nat. Conf. on Dock & Harbour Engg, Surathkal, p 583–588Google Scholar
  27. Nair SM, Balchand AN, Prashob KV, Shaiju P (2013) Mobilization of trace metals in a tropical turbid estuary influenced by a monsoon season. Environ Earth Sci 70:807–819CrossRefGoogle Scholar
  28. Patchineelam SM, Kjerfve B (2004) Suspended sediment variability on seasonal and tidal time scales in the Winyah Bay estuary, South Carolina, USA. Estuar Coast Shelf Sci 59:307–318CrossRefGoogle Scholar
  29. Rasheed K (1997) Studies on dredging impact assessment at Cochin: a tropical estuarine harbor. Ph.D thesis, Cochin University of Science and Technology, IndiaGoogle Scholar
  30. Renosh PR, Rasheed K, Balchand AN (2010) Studies on tide depended salt-silt wedge and identification of turbidity maxima in cochin estuary. Indian J Mar Sci 39(1):136–142Google Scholar
  31. Revichandran C, Srinivas K, Muraleedharan KR, Rafeeq M, Amaravayal S (2012) Environmental set-up and tidal propagation in a tropical estuary with dual connection to the sea (SW coast of India). Environ Earth Sci 66:1031–1042. doi: 10.1007/s12665-011-1309-0 CrossRefGoogle Scholar
  32. Schettini CAF, Ricklefs K, Truccolo EC, Golbig V (2006) Synoptic hydrography of a highly stratified estuary. Ocean Dynam 56(3–4):308CrossRefGoogle Scholar
  33. Shen J, Shen HT, Pan DA, Xiao CQ (1995) Analysis of transport mechanism in turbidity maximum in the Yangtze River estuary. Acta Geograph Sin 50:411–419 (in Chinese)Google Scholar
  34. Shivaprasad A, Vinita J, Revichandran C, Manoj NT, Srinivas K, Reny PD, Ashwini R, Muraleedharan KR (2013a) Influence of saltwater barrage on tides, salinity and chlorophyll a in cochin estuary, India. J Coastal Res 29(6):1382–1390CrossRefGoogle Scholar
  35. Shivaprasad A, Vinita J, Revichandran C, Reny PD, Deepak MP, Muraleedharan KR, Naveen Kumar KR (2013b) Seasonal stratification and property distributions in a tropical estuary (cochin estuary, west coast, India). Hydrol Earth Syst Sc 17:187–199. doi: 10.5194/hess-17-187-2013 CrossRefGoogle Scholar
  36. Syvitski JPM, Vorosmarty CJ, Kettner AJ, Green P (2005) Impact of humans on the flux of terrestrial sediment to the global coastal ocean. Science 308:376. doi: 10.1126/science.1109454 CrossRefGoogle Scholar
  37. Todd VL, Todd IB, Gardiner JC, Morrin EC, MacPherson NA, DiMarzio NA, Thomsen F (2015) A review of impacts of marine dredging activities on marine mammals. ICES J Mar Sci 72(2):328–340. doi: 10.1093/icesjms/fsu187 CrossRefGoogle Scholar
  38. Uncles RJ, Stephens JA (1989) Distributions of suspended sediment at high water in a macrotidal estuary. J Geophys Res 94:395–405CrossRefGoogle Scholar
  39. Uncles RJ, Elliott RCA, Weston SA (1985a) Dispersion of salt and suspended sediment in a partly mixed estuary. Estuaries 8:256–269CrossRefGoogle Scholar
  40. Uncles RJ, Elliott RCA, Weston SA (1985b) Observed fluxes of water, salt and suspended sediment in a partly mixed estuary. Estuar Coast Shelf Sci 20:147–167CrossRefGoogle Scholar
  41. Vale C, Sundby B (1987) Suspended sediment fluctuations in the Tagus estuary on semi-diurnal and fortnightly time scales. Estuar Coast Shelf Sci 25:495–508CrossRefGoogle Scholar
  42. Vinita J, Shivaprasad A, Revichandran C, Manoj NT, Muraleedharan KR, Binzy J (2015a) Salinity response to seasonal runoff in a complex estuarine system (cochin estuary, west coast of India). J Coast Res. doi: 10.2112/JCOASTRES-D-13-00038.1 Google Scholar
  43. Vinita J, Shivaprasad A, Manoj NT, Revichandran C, Naveenkumar KR, Jineesh VK (2015b) Spatial tidal asymmetry of cochin estuary, west coast. India Journal of Coastal Conservation: Planning and Management. doi: 10.1007/s11852-015-0405-9 Google Scholar
  44. Vinita J, Lallu KR, Revichandran C, Muraleedharan KR, Jineesh VK, Shivaprasad A (2015c) Residual fluxes of water and nutrient transport through the main inlet of a tropical estuary, cochin estuary, west coast. India Environ Monit Assess 187:675. doi: 10.1007/s10661-015-4870-2 CrossRefGoogle Scholar
  45. Wai OWH, Wang CH, Li YS, Li XD (2004) The formation mechanisms of turbidity maximum in the Pearl River estuary, China. Mar Pollut Bull 48:441–448CrossRefGoogle Scholar
  46. Wolanski E, Andutta FP, Delhez E (2012) Estuarine hydrology. In: Bengtsson L, Herschy R, Fairbridge R (eds) Encyclopedia of lakes and reservoirs. Springer, New YorkGoogle Scholar
  47. Yu Q, Wang Y, Gao J, Gao S, Flemming B (2014) Turbidity maximum formation in a well-mixed macrotidal estuary: the role of tidal pumping. J Geophys Res Oceans 119:7705–7724. doi: 10.1002/2014JC010228 CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2017

Authors and Affiliations

  1. 1.Regional CentreCSIR-National Institute of OceanographyKochiIndia
  2. 2.CSIR-National Institute of OceanographyDona PaulaIndia
  3. 3.General Commission for Survey (Govt. of Saudi Arabia)RiyadhSaudi Arabia

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