![]() The recovery of the benthic community is expected to take place within 1.5 to 3 years, after completion of the dredging activity. The impact of dredging is observed to be localized. The impact of increased suspended solids, turbidity levels and nutrients is seen in near-field (< 1 km) from the dredging location which do not constitute an hazard. Deep dredging operations required for mining the shell deposits will have impact on benthic community in the area of dredging. Shell deposits in the proposed area lies roughly between 3m to 8m from the estuarine bottom. Submitted to The Government of Kerala, Thiruvananthapuram, 47 p. (2006) Report of the Committee of Experts on Ecological and Environmental Impact of Dredging at Vaduthala Kayal and Vaikam Kayal, Kerala. Ravindran, K., Appukuttan, K.K., Sivasankara Pillai, V.N. The absence of a major longterm disruption to the benthos in the disposal area was probably due to (1) strong tidal currents, which rapidly dispersed the moderate amount of mud sediments released (2) surface disposal, permitting wider dispersal and (3) disposal during late autumn, a period of low faunal recruitment. Most differences noted in community structure between collection dates were attributed to sampling and seasonal variability. Detrimental effects on benthic macrofauna in the area of open water disposal were minimal. Rapid recovery was primarily attributed to immigration through slumping of channel wall sediments similar to those dredged. These effects appeared to be short term, with substantial recovery occurring within 3 months. Effects at the dredged sites included decreased macrofaunal abundance and changes in species composition. Approximately 28,475 m3 of muddy sediments were dredged from a shoal in a South Carolina estuarine system and released near the surface at a nearby site having high tidal current velocities.
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