468
A.A. NEYMAN, M. N. SOKOLOVA, N. G. VINOGRADOVA, and F. A. PASTERNAK:
The quantitative abundance of bottom fauna in the Indian Ocean which extends over
the tropical and southern temperate zones is generally determined by the same regularities
that govern the development of benthic life in all oceans (Fig. 1).
In the northern part of the Indian Ocean the highest biomass of benthos is found, as
was to be expected, in the near-shore regions of continents and islands bordering the ocean.
However, it is only at single stations that the biomass of benthos reaches values of several
hundred g m- 2 , which are quite common on the continental shelf of temperate latitudes.
But even within the shelf the main areas of the northern part of the ocean, the Arabian
Sea and the Bay of Bengal, are not equivalent in regard to their benthic productivity. The
Fig. 1. Distribution of benthos biomass in the Indian Ocean (g m -2)
Arabian Sea is characterized by a richer bottom fauna (SOKOLOVA and PASTERNAK, 1962),
and on its northern coasts we discovered a biomass exceeding 500 gm- 2 , the maximum
value recorded for the Indian Ocean. However, the average benthos biomass in this part
of the coast does not exceed 35 g m- 2 • Southward, along the coasts of the Arabian
peninsula and Africa down to the Strait of Mozambique, it decreases gradually (on the
average from 15 - 20 to 3 - 5 g m -2). A decrease in the biomass of bottom fauna from
25 - 30 to 5 g m -2 is also observed along the western coasts of India. The abundance of
bottom life in the southern parts of the Arabian Sea is due to an inflow of equatorial
waters of low salinity causing a strongly expressed stratification of water masses
(ELIZAROV, 1968). In the parts of the shelf under consideration the bottom fauna is richest
at a depth of 25 -75 m and extremely poor at 80 -150m due to an inflow at this depth of
subsurface water with a low 02 content.
In accordance with the general productivity of the northern part of the ocean, the
bottom fauna on the shelf of the Bay of Bengal and the Andaman Sea was found to be
A.A. NEYMAN, M. N. SOKOLOVA, N. G. VINOGRADOVA, and F. A. PASTERNAK:
The quantitative abundance of bottom fauna in the Indian Ocean which extends over
the tropical and southern temperate zones is generally determined by the same regularities
that govern the development of benthic life in all oceans (Fig. 1).
In the northern part of the Indian Ocean the highest biomass of benthos is found, as
was to be expected, in the near-shore regions of continents and islands bordering the ocean.
However, it is only at single stations that the biomass of benthos reaches values of several
hundred g m- 2 , which are quite common on the continental shelf of temperate latitudes.
But even within the shelf the main areas of the northern part of the ocean, the Arabian
Sea and the Bay of Bengal, are not equivalent in regard to their benthic productivity. The
Fig. 1. Distribution of benthos biomass in the Indian Ocean (g m -2)
Arabian Sea is characterized by a richer bottom fauna (SOKOLOVA and PASTERNAK, 1962),
and on its northern coasts we discovered a biomass exceeding 500 gm- 2 , the maximum
value recorded for the Indian Ocean. However, the average benthos biomass in this part
of the coast does not exceed 35 g m- 2 • Southward, along the coasts of the Arabian
peninsula and Africa down to the Strait of Mozambique, it decreases gradually (on the
average from 15 - 20 to 3 - 5 g m -2). A decrease in the biomass of bottom fauna from
25 - 30 to 5 g m -2 is also observed along the western coasts of India. The abundance of
bottom life in the southern parts of the Arabian Sea is due to an inflow of equatorial
waters of low salinity causing a strongly expressed stratification of water masses
(ELIZAROV, 1968). In the parts of the shelf under consideration the bottom fauna is richest
at a depth of 25 -75 m and extremely poor at 80 -150m due to an inflow at this depth of
subsurface water with a low 02 content.
In accordance with the general productivity of the northern part of the ocean, the
bottom fauna on the shelf of the Bay of Bengal and the Andaman Sea was found to be