Leaching of Total Phosphorus in Greenhouse Soil in Relation to Soil Fertility and Fertilizer Application

Abstract

Inappropriate applications of phosphorus (P) in agricultural production lead to the leaching loss of P, which subsequently contributes to the eutrophication of water bodies. A leaching experiment using unsaturated intact soil columns was conducted to study the influence of fertilizer application on leaching of phosphorus in a gley meadow soil at different fertility levels (low-, medium and high fertility levels). The soil column at each fertility level received three fertilization treatments (control [CK], manure [M] and chemical fertilizer [F]). The results indicated that the leaching loss of total P (TP) from the soil column was induced by the P input from either manure or chemical fertilizer application, and the extent of leaching loss of P was also positively related to the soil fertility level. In addition, the TP concentrations in the leachates from all fertilization treatments exceeded the critical value for water eutrophication (0.02 mg P/L). This suggests that applications of manure and chemical fertilizer at proper rates with close consideration of the soil fertility level are essential to reduce the leaching loss of TP to the environment.