An annual cycle, at constant temperature, in a model sandy beach. I. Nutrient chemistry

Abstract A model sandy beach, successfully mimicking the natural environment has been operated under controlled conditions at a constant temperature (5°C, representative of British winter coastal sea-water temperatures) for a year. The nutrient chemistry (nitrate, nitrite, ammonium, phosphate) and dissolved oxygen concentration of the beach ground water and its inundating sea water has been monitored over that period. The nitrifying activity of the sand profile and the associated oxygen status of the beach appear to be the dominant characteristics of the system. The role of the beach sand as self-regulating, self-purifying and thus a cleansing filter of sea water is considered.