eutrophic state to an oligotrophic state.
Areas so affected are called eutrophic, whilst more remote ocean waters which become starved of nutrients in summer are referred to as oligotrophic.
This implies that the food web structure and primary productivity are uncoupled in the oligotrophic gyres.
AMT sampling covers almost the entire gradient of oceanic productivity from oligotrophic ocean gyres to seasonally high productive high latitude and equatorial upwelling waters.
River Derwent and Bassenthwaite Lake Cumbria The Derwent represents brook lamprey Lampetra planeri in a high-quality, oligotrophic river in northern England.