A study of the hydrological features of the shelf water along the west coast of India with an attempt to explain their influence upon the living resources of the region

The objective of the present study is to elucidate the hydrological conditions of the shelf waters along the southern half or the west coast of India and their relation to the sooplankton bionase and pelagic fish resources. Data from six hydrography-plankton sections worked during the 1972-75 period of cape camerin. Quilon. cochin. Kasaragod. Karwar and kotnagiri formed the basis of the present study.Stations were fixed along the transects 10 nautical miles apart. Starting with the first station at around 15 metre depth and were usually occupied 5 to 8 times in an year at an interval of about 6 weeks. Data relating to oil sardines and macherel fisheries were availed from published information relating to the period mainly of the Central Marine fisheries Research Institute. The range of different parameters namely temperature. salinity. density and dissolved oxygen at different depths and their sloping features against the coast are discussed. Three seasons. namely south-west monsoon (summer monsoon). north-east monsoon (winter monsoon) and hot weather season are designated and data of the core months of each of these seasons considered in the study.

Biogeochemistry of the shelf sediments of south eastern Arabian sea: Effect on benthic bacterial heterotrophs

The composition and variability of heterotrophic bacteria along the shelf sediments of south west coast of India and its relationship with the sediment biogeochemistry was investigated. The bacterial abundance ranged from 1.12 x 103 – 1.88 x 106 CFU g-1 dry wt. of sediment. The population showed significant positive correlation with silt (r = 0.529, p< 0.05), organic carbon (OC) (r = 0.679, p< 0.05), total nitrogen (TN) (r = 0.638, p< 0.05), total protein (TPRT) (r = 0.615, p< 0.05) and total carbohydrate (TCHO) (r = 0.675, p< 0.05) and significant negative correlation with sand (r = -0.488, p< 0.05). Community was mainly composed of Bacillus, Alteromonas, Vibrio, Coryneforms, Micrococcus, Planococcus, Staphylococcus, Moraxella, Alcaligenes, Enterobacteriaceae, Pseudomonas, Acinetobacter, Flavobacterium and Aeromonas. BIOENV analysis explained the best possible environmental parameters i.e., carbohydrate, total nitrogen, temperature, pH and sand at 50m depth and organic matter, BPC, protein, lipid and temperature at 200m depth controlling the distribution pattern of heterotrophic bacterial population in shelf sediments. The Principal Component Analysis (PCA) of the environmental variables showed that the first and second principal component accounted for 65% and 30.6% of the data variance respectively. Canonical Correspondence Analysis (CCA) revealed a strong correspondence between bacterial distribution and environmental variables in the study area. Moreover, non-metric MDS (Multidimensional Scaling) analysis demarcated the northern and southern latitudes of the study area based on the bioavailable organic matter