Effects of freeze-drying and use of artificial seawater on phosphorus exchange isotherms in brackish water sediments

Abstract This study reports results on the estimated magnitude of changes in P sorption isotherms clayey mud sediments when performed using (1) freeze-dried instead fresh sediment samples and (2) artificial sea water (ASW) ambient near-bottom water. The used differed their sorption. For isotherms, were equilibrated for 48 h solutions varying concentration whereafter amount sorbed or desorbed was determined. We adjusted modified Freundlich equation to isotherm data assessed differences between treatments by comparing equilibrium concentrations buffering capacities determined from equation. Freeze-drying decreased all investigated sediments, but varied depending properties sediments. effect minor abundant sites low easily exchangeable P, while it clearer originally high surfaces. ASW produced similar suggesting that is a suitable solution exchange experiments with muddy clay enlightens processes occurring freeze-drying. highlight examining effects dissimilar experimental conditions significance observed should be evaluated proper context considering precision method. Article highlights freeze-drying are unoccupied Artificial background matrix isotherms. method considered differing treatments.