standardization of environmental data and information - International ...

3.4. Benthic and demersal community composition
The benthic and demersal communities in the CCFZ and the Indian
Ocean claim area have not yet been adequately characterised. Generally, in
both of these deep-seabed areas as well as in other deep ocean basins, the
communities are essentially dependent for their nutrition on the organic
content of falling detrital material from surface waters. No active
hydrothermal vent communities are known in these areas and, obviously,
no photosynthesis is possible.
Environmental impacts of mining on the benthic communities are
probably the most poorly understood class of impacts of all those that must
be considered. Growth rates of individuals and recovery rates of
populations following disturbance may be very slow and need to be
estimated before reasonable impact assessment can be attempted.
Establishment of an adequate environmental baseline
characterisation for the benthic communities in the contractors’ exploration
areas is probably the most challenging problem that must be faced in the
environmental assessment of deep-seabed mining. Certainly one of the
highest priorities for this Workshop should be the development of standards
that can be used to integrate existing collections and observations into
comparable data sets, and to promote uniform collection methods in future
investigations
3.5. Climate, ocean circulation and water chemistry
The climate in the Indian Ocean is dominated by the monsoon
seasons, including the northeast monsoon (December to April) and
southwest monsoon (June to October). Tropical cyclones occur during
January-February. Several currents make up the Indian Ocean's current
system. The North Equatorial (November-April) and South Equatorial
currents, Monsoon Drift, northeast monsoon (in April) and Antarctic
Circumpolar currents all affect the flow of currents in the Indian Ocean. In
the Indian claim area, these all contribute to a net westward flow of the
surface currents year round. 10 General seawater components in the Indian
claim area are representative of the low nutrient, oligotrophic tropical
environments typical of both the central Indian Ocean and the CCFZ.
The climate in the CCFZ is similarly tropical and subtropical, and is
dominated by the northeastern trade winds during much of the year. In the
107 INTERNATIONAL SEABED AUTHORITY