Variation of Chemical Properties of Ground Water in Farm Land

Variation of Anion Concentration

Abstract

Effect of the fertilizer on chemical properties of ground water was investigated from March to November in a farm land of West of Fukuoka City. The variation of dissolved oxygen (DO) and nitrate (NO3-N) concentrations in ground waters with time was greatly different by the surface conditions of the land: paddy field or vegetable field. In the case of the former, the DO and NO3-N concentrations decreased gradually from May and showed a minimum at the end of August. While, in the case of the latter, the concentrations were highly constant. Despite that the large amount of phosphate was manured, its concentration in ground waters was low.