Keywords
Dredging
Benthos
Harbour
Impact.
How to Cite
Abstract
Recolonization of benthos following dredging operations was studied in Mormugao Port Trust Harbour, Goa. Six stations were fixed for sampling within the radius of the dredging site. Three samples each were collected during dredging and after dredging. The proportion of gravel in the sediment of the dredged site increased after dredging, while that of organic matter decreased. The impact on community was estimated at species level, using both univariate and multivariate analyses. Maximum negative effect was observed during dredging where a reduction by 60-70 % on macrofauna was evident. Within six weeks after dredging the density of the polychaete Clymene annadalei increased in the dredging site, while typical ‘opportunistic’ species such as Capitella capitata was not favoured by dredging. Favourable condition for resettlement of benthic communities is probably available in about four months.References
Black, K.P. & G.D. Parry (1994): Sediment transport rates and sediment disturbance due to scallop dredging in Port Philip Bay. Mem Queensl Mus. 36: 327-341.
Buchanan, J.D. & J.M. Kain (1984): Measurement of the physical and chemical environment. Pp. 30-50. In: Holme, N.L. & A.D. McIntyre (Eds): Methods for the study of marine benthos. Blackwell Scientific Publication, Oxford.
Eleftheriou, A. & N.A. Holme (1984): Methods for the study ofMarine Benthos: Macrofauna Techniques. Pp. 140-216. In: Holme, N.A. & A.D. McIntyre (Eds): Blackwell Scientific, London.
Estacio F.J., E.M. Garcia-Adiego, D.A .Fa , J.C. Garcia-Gomez, J.L. Daza, F. Hortas & J.L. Gomez-Arzia (1997): Ecological analysis in a polluted area of Algeciras Bay (Southern Spain): external ‘versus’ internal outfalls and environmental implications. Mar. Pollut. Bull. 34(10): 780-793.
Gislason, H. (1994): Ecosystem effects of fishing activities in the North Sea. Mar. Poll. Bull. 29: 520-527.
Giovanardi, O., F. Pranovi & G. Franceschini (1998): “Rapido†trawl fishing in the Northern Adriatic: preliminary observations of the effects on the macrobenthic communities. Acta Adriat. 31(1): 37-52.
Guerra-Garcia, J.M., J. Corzo & J.C. Garcia-Gomez (2003): Short¬ term benthic recolonization after dredging in the harbour of Ceuta, North Africa. Mar. Ecol. 24(3): 217-229.
Harkantra, S.N. (1975): Benthos of Kali estuary, Karwar. Mahasagar-Bull. Natl. Inst. Oceanogr. 8: 53-58.
Harkantra, S.N. & A.H. Parulekar (1985): Community structure of sand dwelling macrofauna of an estuarine beach in Goa, India. Mar. Ecol. Prog. Ser. 30: 291-294.
Harkantra, S.N. & N.R. Rodrigues (2003): Pattern of species succession of soft-bottom macrofauna in the estuaries of Goa, west coast of India. Curr. Sci. 85(10): 1458-1464.
Hily, C. & M. Glemarec (1990): Dynamique successionnelle des peuplements de fonds meubles au large de la Bretagne. Ocean. Acta 13: 107-115.
Johnson, G (1981): Estuarine dredge and fill activities: a review of impacts. Environ. Mgmt. 5: 427-440.
Johnson, R.O. & W.G. Nelson (1985): Biological effects of dredging in an offshore burrow area. FI. Scientist 48: 166-187.
Jones, J.B. (1992): Environmental impact of trawling on the seabed: a review. New Zeal J. Mar Freshwater Res. 26: 59-67.
Lopez-Jamar, E. & J. Mejuto (1988): Infaunal benthic recolonization after dredging operations in La Coruna Bay, NW Spain. Cah. Biol. Mar. 29: 37-49.
Lewis, M.A., D.E. Weber, R.S. Stanley & J.C. Moore (2001): Dredging impact on an urbanized Florida bayou: effects on benthos and algal-periphyton. Environ. Pollut. 115: 161-171.
Margalef, R. (1958): Information theory in ecology. Gen. Syst. 3: 36-71.
McCall, P.L. (1977): Community patterns and adaptive strategies of the infaunal benthos of Lon Island Sound. J. Mar. Res. 35: 221-226.
McCauley, J.E., R.A. Parry & D.R. Hancock (1977): Benthic infauna and maintenance dredging: a case study. WaterRes 11:233-242.
Morton, J.W. (1977): Ecological effects of dredging and dredge disposal: a literature review. Tec. Papers. US Fish Wildl. Serv. 94: 1-33.
Morton, B. (1996): The subsidiary impacts of dredging (and trawling) on a subtidal benthic molluscan community in the southern waters of Hong Kong. Mar. Poll. Bull. 32(10): 701-710.
Newell, R.C., L.J. Seiderer & D.R. Hitchcock (1998): The impact of dredging works in coastal waters: a review of the sensitivity to disturbance and subsequent recovery of biological resources on the sea bed. Oceanogr. Mar. Biol. Annu. rev. 36: 127-178.
Peelou, E.C. (1966): The measurement of diversity in different types of biological collections. J. Theor. Biol. 13: 131-144.
Parulekar, A.H., V.K. Dhargalkar & S.Y.S. Singbal (1980): Benthic studies in Goa estuaries: Part III-Annual cycle of macrofauna distribution production and trophic relations. Indian J. Mar. Sci. 9: 189-200.
Peterson, C.H., H.C. Summerson & S.R. Fegley (1987): Ecological consequences of mechanical harvesting of clams. Fish Bull US 85: 281-298.
Pranovi, F., O. Giovanardi & G. Franceschini (1998): Recolonization dynamics in areas disturbed by bottom fishing gears. Hydrobiologia 375/376: 125-135.
Qasim, S.Z. & R. Sen Gupta (1981): Environmental characteristics of the Mandovi-Zuari estuarine system in Goa, India. EstuarCoast ShelfSci. 13: 557-578.
Rathod, V., Z.A. Ansari & A.H. Parulekar (1991): Benthic fauna of Kakinada bay and backwaters, east coast of India. Indian J. Mar. Sci. 20: 195-199.
Rhoads, A.D. & L.F. Boyer (1982): The effects on marine benthos on physical properties of sediments: A successional perspectives. Pp. 3-52. In: McCall, P.L. & M.J.S. Tevesz (Eds): Animal- Sediment Relations. Plenum Press, New York.
Shannon, C.E. & W. Weaver (1963): The Mathematical Theory of Communication. University of Illinois Press, Urbana, Illinois. 117 pp.
Shetye, S.R., A.D. Gouveis, S.Y. Singbal, C.G. Naik, D. Sundar, GS. Michael & G. Nampoothiri (1995): Propogation of tides in Mandovi-Zuari estuarine network. Proc. Indian Acad. Sci. (Earth Planet. Sci.) 4: 667-682.
Snelgrove, P.V.R. (1998): The biodiversity of macrofaunal organisms in marine sediments. Biodiversity and Conservation 7: 1123-1132.
Trueblood, D.D., E.D. Gallagher & D.M. Gould (1994): Three stages of succession on the Savin Hill Cove mudflat, Boston Harbour. Limnol. Ocenogr. 44: 1430-1454.
Zajac, R.N., R.B. Robert & R.B. Whitlatch (1982): Response estuarine infauna to disturbance, II. Spatial and temporal variation of succession. Mar. Ecol. Prog. Ser. 10: 15-27.
Zajac, R.N., R.B. Whitlatch & S.F. Thrush (1998): Recolonization and succession in soft-sediment infaunal communities: the spatial scale of controlling factors. Hydrobiologia 375/376: 227-240.