L - Cochin University of Science and Technology

a life span of about 3 months (Sajan, 2003), and then the annual production will be of
993.6 kg C/km2/yr
The area covered in the present study is approximately 55000 km 2 . An average
biomass of 4.16 g/m 2 when converted to annual benthic production (Slobodkin,
1962) gives a value of 8.32 g/m 2 /y. The benthic production in tenns of wet weight in
the study area of 55000 km 2 will be 0.46 million tones. Since transfer of energy to the
next trophic level is approximately 10 %, production transferred to the tertiary level
will be 0.046 million tonnes.
Meiobenthic annual production will be 11520 kg/km2 (2880 kg/km2 *4) and
production from the study area will be 0.6336 million tones. So the total benthic
production (macro+meio) will be 1.0936 miilion tones. Considering an ecological
transfer efficiency of 10 %, benthic potential will be 0.10936 million tones.
According to Somvanshi (1998) present exploitation is 1.875 million tons/y
along the west coast of India. Assuming that 92.9 % of which is supported by
continental shelf within 200 m depth zone the production will be 1.75 million tons
(m. 1.) of which demersal fishery contribute 49% (Sudarsan et aI., 1990). the benthic
fish production in the continental shelf will be 0.8558 m. t. Considering the area of
the western continental shelf is 75000 km 2 , which supports 0.8558 m. t. benthic fish
production, the average demersal fish production in the northwest continental shelf
will be about 0.5159 m. t. In the present study, annual benthic potential yield is
0.10936 m t, which can support 21.2% of the current demersal fishery yield of 0.5159
m t. Limitations of the present study were the sampling was done in the 30-200 m
and benthic biomass below 30 m depth has not included in the present study.
Moreover, epifauna and microfuana, which also contributed significant role to
benthic production, were not taken into consideration.
Average surface primary production obtained in the near to the coast from the
two seasons was 20.43 mg C/m3/d and surface chlorophyll a production was 0.64
mg/m 3 and off coast stations surface primary production was 9.50 mg C/m3/d and
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