Tamar Estuary, Plymouth, south west England

Ammonium and ammonia concentration parameters in water bodies; Dissolved oxygen parameters in the water column; Optical backscatter; Salinity of the water column; Concentration of suspended particulate material in the water column; Nitrite concentration parameters in the water column; Turbulence in the water column

Optical backscatter sensors; discrete water samplers; salinity sensor; autoanalysers; dissolved gas sensors

Seasonal observations of the axial distributions of nitrite and ammonia in the near-surface water of the Tamar estuary were made together with observations of the distribution of salinity, turbidity and dissolved oxygen. These data were used to deduce the processes contributing to the interactive behaviour of nitrite and ammonia in the Tamar estuary. Twelve surveys of the estuary were completed between June 1980 and September 1981 using a 12m length flat bottomed Rotork Seatruck. The majority of surveys were carried out within 2 days of maximal neap tide conditions. On each occasion a single axial traverse between the mouth and a weir marking the head of the estuary was completed within three hours, usually around high water. Extension of the transect to the weir included a stretch of fresh water (ranging between 5 and 15km, depending on river discharge), which provided an indication of short term variability in the concentration of nitrite and ammonia delivered to the estuarine mixing zone. A primary supply of water was pumped from a depth of 0.5m using a submersible pump. The salinity, suspended particle load and dissolved oxygen content of this water were determined. A subsidiary filtered stream was used for continuous autoanalytical determinations of ammonia and nitrite. Analyses by the method of standard additions of discrete water samples collected at salinity intervals of 5 were used to calibrate the continuous record. The outputs were corrected for refractive index errors.

Morris, A.W., Howland, R.J.M., Woodward, E.M.S., Bale, A.J. and Mantoura, R.F.C. (1985) Nitrite and ammonia in the Tamar estuary., Netherlands Journal of Sea Research. Vol 19(3-4): 217-222.

Plymouth Marine Laboratory
Prospect Place The Hoe
Plymouth
England
PL1 3DH
United Kingdom