standardization of environmental data and information - International ...

?? Investigate the plankton community in the upper 200 m;
?? Evaluate bioturbation rates;
?? Obtain data on the flux of materials from the upper water column
down to the deep sea;
?? Determine the frequency, duration and spatial distribution of
baseline monitoring.
5. Environmental characterisation of claim areas
Two regions in the deep seabed currently have exploration claims
registered with ISA. First, the Government of India has claimed an area in
the south central Indian Ocean between 10-17° south latitude and 72-82°
east longitude. Second, six States and an intergovernmental group (China,
France, India, Japan, Republic of Korea, Russian Federation and an Eastern
European group) have claims in the northeastern tropical Pacific Ocean (the
CCFZ) between 7-18° N and 157-118° west longitude (see figure 2).
This section summarises the environmental baseline information
presented in Morgan, Odunton and Jones. 12 It outlines the environmental
information available for the claim areas and focuses on general
parameters relevant to environmental impact assessment.
5.1. Occurrence of commercial nodule deposits
Manganese nodules form along gradients of ambient water
chemistry in which waters traverse from relatively acidic and low oxygen
levels into relatively high levels (see section 3.1 above). Acidic, poorly
oxygenated waters can contain significant amounts of dissolved and
organically complexed metals. Where these waters pick up oxygen and
usually at the same time lose some acidity, many metals will rapidly oxidise
and precipitate out. This situation commonly occurs at the water/sediment
interface in lakes and oceans, which is where manganese nodules are
usually found. Iron and manganese are the most common transition metals
in the earth’s crust, and thus form the bulk of the precipitated material.
Manganese oxides also have special surfaces that are particularly effective
in collecting and holding more manganese and other metals, scavenging
them preferentially from the bypassing water flow.
INTERNATIONAL SEABED AUTHORITY 112