Nitrogen and phosphorus leaching and vegetative growth of maize as affected by organic manure application

Abstract

Maize production in Asia is rapidly increasing. For its sustainable production, the effects of raw and dry manure application on soil water dynamics, nutrient leaching, and plant growth were investigated. Nitrogen (N) and phosphorus (P) concentrations in the percolated water below a 110-cm depth of field-lysimeter columns were analyzed to quantify leaching. Soil water, soil temperature, and plant growth were routinely monitored. The manure application practices increased soil water content by 0.008–0.025 cm3 cm-3 throughout the vegetative period by reducing bulk density and reduced the daytime temperature range by 0.4–1.2°C. The average leaching concentrations of total N increased from 2.6 to 4.7 mg N L-1 and available P decreased from 0.12 to 0.04 mg P L-1 between 63 and 93 DAS (day after sowing), respectively. The manure treatments did not increase nutrient leaching load at 63 DAS, but at 93 DAS the N load was increased by 219– 324 g ha-1 and P load by 2.0–3.1 g ha-1 compared with the control treatment. The dry manure released a larger amount of N (30.7%) and P (3.2%) in the leachates than the raw manure. The dry and raw manure treatment produced 14.5 and 5 cm taller plants, respectively than the control treatment. Manure application with a slight modification in nutrient management can avoid the nutrient leaching problem.