The scientists have also linked changes in the zone to nutrient levels in the river over a period of the last 200 years, based on radioisotope dating of mud cores taken from the sea bed.
(The scientists; have linked; changes in the zone) (radioisotope; dating; of mud cores) (mud cores; taken; from the sea bed)
The scientists radioisotope mud cores
have linked dating taken
changes in the zone
of mud cores
from the sea bed