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J. Ojeda Zújar et al.
two sites in the upper reaches of the Odiel, to characterize the river water and
marsh drainage channels which join at this point
in the confluence of the Burro and Punta Umbria channels because of the
significant interest of the interchange between the Odiel and the Punta
Umbria channels
For low tide: the interchange between estuarine and coastal waters is the outstanding
point of interest; so all new sampling points are all proposed for the exit of the estuary.
one in the lowest reach of the Punta Umbria channel. Proposed because much
of the interchange of estuarine and coastal waters passes through this point,
especially the ebb of turbid estuarine waters. These are the ones most likely to
be affected by high levels of contamination and the ones most in need of