Effect of intermittent aeration mode on nitrogen concentration in the water column and sediment pore water of aquaculture ponds

Nitrogen in pond sediments is a major water quality concern and can impact the productivity of aquaculture.Dissolved oxygen is an important factor for improving water quality and boosting fish growth in aquaculture ponds,and plays an important role in the conversion of ammonium-nitrogen(NH4-N) to nitrite-nitrogen(NO_2~--N) and eventually nitrate-nitrogen(NO_3~--N).A central goal of the study was to identify the best aeration method and strategy for improving water quality in aquaculture ponds.We conducted an experiment with six tanks,each with a different aeration mode to simulate the behavior of aquaculture ponds.The results show that a 36 hr aeration interval(T_c=36 hr:36 hr) and no aeration resulted in high concentrations of NH4-N in the water column.Using a 12 hr interval time(T_c=12 hr:12 hr) resulted in higher NO_2~--N and NO_3~--N concentrations than any other aeration mode.Results from an 8 hr interval time(T_c=8 hr:8 hr) and 24 hr interval time(T_c=24 hr:24 hr) were comparable with those of continuous aeration,and had the benefit of being in use for only half of the time,consequently reducing energy consumption.