TY - JOUR
T1 - Sedimentary pools of phosphorus in the eutrophic Tamar estuary (SW England)
AU - Monbet, Phil
AU - McKelvie, Ian
AU - Worsfold, Paul
PY - 2010
Y1 - 2010
N2 - The speciation of phosphorus in Tamar estuary sediment has been determined at eight stations from
Gunnislake (riverine end-member) to Torpoint (marine end-member) using the SEDEX (sedimentary
extraction) sequential extraction scheme. The seasonal variability of total phosphorus and each of the
five fractions is discussed. Total phosphorus, in the range 26a??51 mmol g 1, was stored in the relatively
labile fractions, particularly in the iron oxide fraction. The well oxygenated waters of the macrotidal
Tamar estuary ensure that the surface sediment layer remains oxic, providing an effective barrier that
retains dissolved reactive phosphorus (DRP) within the sedimentary iron oxide fraction and prevents
phosphorus migration from the sediment to the water column. The exchangeable and organic
phosphorus sedimentary pools, although small, are therefore the main potential sources of phosphorus
release to the water column. In particular, this study shows that exchangeable phosphorus and
dissolved organic phosphorus (DOP) in the pore water are intimately linked. Finally, the distribution of
phosphorus in the estuary is strongly influenced by particle morphology, with most of the sedimentary
phosphorus forms exhibiting significant positive correlations with the percent of each grain size.
AB - The speciation of phosphorus in Tamar estuary sediment has been determined at eight stations from
Gunnislake (riverine end-member) to Torpoint (marine end-member) using the SEDEX (sedimentary
extraction) sequential extraction scheme. The seasonal variability of total phosphorus and each of the
five fractions is discussed. Total phosphorus, in the range 26a??51 mmol g 1, was stored in the relatively
labile fractions, particularly in the iron oxide fraction. The well oxygenated waters of the macrotidal
Tamar estuary ensure that the surface sediment layer remains oxic, providing an effective barrier that
retains dissolved reactive phosphorus (DRP) within the sedimentary iron oxide fraction and prevents
phosphorus migration from the sediment to the water column. The exchangeable and organic
phosphorus sedimentary pools, although small, are therefore the main potential sources of phosphorus
release to the water column. In particular, this study shows that exchangeable phosphorus and
dissolved organic phosphorus (DOP) in the pore water are intimately linked. Finally, the distribution of
phosphorus in the estuary is strongly influenced by particle morphology, with most of the sedimentary
phosphorus forms exhibiting significant positive correlations with the percent of each grain size.
UR - http://pubs.rsc.org/en/content/articlepdf/2010/em/b911429g
U2 - 10.1039/b911429g
DO - 10.1039/b911429g
M3 - Article
VL - 12
SP - 296
EP - 304
JO - Environmental Science: Processes & Impacts
JF - Environmental Science: Processes & Impacts
SN - 2050-7887
IS - 1
ER -