Hydro-ecological relations in the Delta Waters

In Tahle 3 a tentative carbon budget of the 4 saline Delta Waters Is
given. as an expression of the transfotmation of inorgank nutrients
into organic carbon of primary pxohcers. Table 3 does not girre
infetmatioa about the turnover of nutrients between the successive
generations of plants. Notwithstazdlng the large dlfkrences in
nutrient loadjags of the separate waters, primasy production of
phytoplankton only shows a difference of a factor 2 between the light
-2 -1
limited, tUrbid Westerschelde (l25 g C m y ) and the clear,
-2 -1
presumably not nutrient limited Veerse Meer (249 g C m y ). The
Oosterseblde and Orevelingemseer hold int-diate positions.
Production of microphytobent!hos (benthic diatoms, gzeen algae etc.) is
roughly one third of the production of phytoplankton. In the
Westerschelde estuary, however, the relative skre of benthic
microphytes is considerahLy higher, based on P/B ratio's derived from
high biomass data, taken on intertidal flats (personal eonrmnaicatFoa
D.J.
de Jong, DW).
OwFng to the relatrvely large surface area of supratidal wetlands, the
contributivn of ahoae-ground peimarp production to the carbon budget in
-9 -1
Westersehelde estusry (60 g C m y is about 20%. The larger part of
the saltmarsh plants is produced in the eastern secrion of the
Westerschelde estuary (Verdrmken Land van Saeftinghe) and is not
transpwrted over the entire estuary, In contrast with the
Westerschelde, the Oosterachelde salt marshes pay only an insignificant
contrLhution (lees thau 5Z) to the system metabolism of the entire
estuary.
Maarophytes growing on bard substretes (i.e. seaweeds attached to
sewalls and stone-clad dilres) have only a minor contriburian to the
carbon budgets of the entire water hobtes, notwithstandiag their high
production per square metre habitat.
Eigh turbidity and exposure to waves and tides prevents the potential
sediment habitats in tke Weatersehelde egtuary from being invaded by
macrephytes, The Oosterschelde estuary has only local growth of
laactophytes an sediment substrams in sbeltered regions (Zandkteek,
Ktabbenkreek, eastern part). In the sheltered, stagnant lagoons