L - Cochin University of Science and Technology
L - Cochin University of Science and Technology
L - Cochin University of Science and Technology
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followed by foraminifers while Rodrigues et al., (1982) reported dominance <strong>of</strong><br />
nematodes followed by polychaetes. Ansari <strong>and</strong> Ingole (1983) <strong>and</strong> Sajan (2003) also<br />
noticed the dominance <strong>of</strong> nematodes followed by harpacticoides. The increased<br />
biomass <strong>and</strong> density in the shallow stations during pre-monsoon may be due to high<br />
surface productivity.<br />
Trend in meiobenthic distribution bctween transects was not disccrnible, but<br />
average values showed relatively high biomass <strong>and</strong> density along the northern<br />
transects. Neyman (1969) showed that benthos were sparse in the northern shelf <strong>of</strong><br />
wcstern India at depths <strong>of</strong> 75-200m, attributing this to the low oxygen content in the<br />
water along the north. Present study reported dominance <strong>of</strong> nematodes among the<br />
other groups in shallow (95%) as well as deeper depths <strong>of</strong> 150 m depth (79%) even<br />
though density <strong>of</strong> total mei<strong>of</strong>aunal <strong>and</strong> nematodes decreased with depth. This can be<br />
explained by the tolerance capacity <strong>of</strong> nematodes in low oxygen conditions as<br />
observed by Damodaran (1973), Gooday et al., (2000) <strong>and</strong> Bernhard et al., (2000).<br />
Sajan (2003) reported 87% <strong>of</strong> the total mei<strong>of</strong>auna represented by nematodes beyond<br />
150 m.<br />
Present study showed that during post-monsoon macrobenthos <strong>and</strong><br />
meiobenthos were more in the shallow depths than deeper depths reveals their<br />
positive relationships among themselves but Desai <strong>and</strong> Krishnankutty (1967) noticed<br />
an inverse relationship between macro <strong>and</strong> mei<strong>of</strong>auna. Average macrobenthic density<br />
was 1372/m 2 <strong>and</strong> 2104/m 2 during post-monsoon <strong>and</strong> pre-monsoon seasons<br />
respectively. Average density irrespective <strong>of</strong> seasons was I 738/m 2 . Average<br />
meiobenthic density during post-monsoon was 169/10 cm 2 (16900/m2) <strong>and</strong> during<br />
pre-monsoon it was 886/10 cm 2 (88600/m2). Average meiobenthic density<br />
irrespective <strong>of</strong> seasons was 52750/m 2 • The relation between macro <strong>and</strong> meiobenthos<br />
in the present study was in the ratio <strong>of</strong> 1 :30. Parulekar et al., (1976) reported an<br />
average ratio <strong>of</strong> macro to mei<strong>of</strong>auna was in the order <strong>of</strong> 1: 16,000 <strong>and</strong> opined that<br />
contribution <strong>of</strong> nematodes <strong>and</strong> foraminifers in the mei<strong>of</strong>auna seems to be the main<br />
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