Nutrient Flux in Litter and Surface Soil after Nitrogen and Phosphorus Fertilization
1978
Kelly, J. M. | Henderson, G. S.
The effect of urea and concentrated superphosphate additions on the movement of N, P, K, and Ca from the litter and top 10 cm of the mineral soil via the soil solution was evaluated in an upland oak forest using tension lysimeters. The range in total flux values for each element over the study period were: N 24.8 to 1145.3; P 2.0 to 633.3; Ca 70.6 to 553.1; and K 49.5 to 94.0 kg/ha in response to various combinations of N and P fertilizer addition at levels of 0, 550, and 1100 kg/ha N and 0, 275, and 550 kg/ha P. Nitrogen fertilizer addition significantly increased the flux of N and K while reducing the flux of P and Ca. Phosphorus fertilizer addition significantly increased N, P Ca, and K fluxes. Solubilization of organic matter and the formation of insoluble calcium ammonium phosphate were important processes regulating the flux of N, P, Ca and K.
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