A Laboratory Evaluation of Ammonia Volatilization and Nitrate Leaching following Nitrogen Fertilizer Application on a Coarse‐Textured Soil

Abstract

In a series of eld studies, di ering rainfall patterns within the rst month a er N fertilizer application to a coarse-textured soil signi cantly a ected yields and N-use e ciency of irrigated corn (Zea mays L.), and responses varied with N source. A laboratory study was conducted to evaluate e ects of N source with precipitation following N application to a coarse-textured soil. Nitrogen sources included urea-ammonium nitrate solution (UAN), UAN with additives of either nitrapyrin (2-chloro-6-[trichloromethyl] pyridine) as a nitri cation inhibitor or maleic-itaconic acid copolymer as a urease and nitri cation inhibitor, or polymer-coated dry urea (PCU). ese products were applied to soil in chambers from which ammonia (NH 3 ) volatilization and nitrate (NO 3 -) leaching were measured over 31 d following fertilization. Precipitation events simulated rainfall frequencies and amounts that occurred in eld studies in dry and wet conditions. Ammonia volatilization was lower in wet than dry conditions. Total NH 3 loss for the dry precipitation regime ranged from 11 to 18% of applied N fertilizer for all treatments except PCU (<1%). In contrast, all treatments in wet conditions had low NH 3 loss (<1% of applied N). However, substantial NO 3 leaching occurred with wet conditions, comprising 48 to 66% of applied N for most treatments. Leaching loss was the greatest for UAN, followed by UAN with additives. For either dry or wet environments, losses of N from PCU to either NH 3 volatilization or NO 3 leaching were negligible.

Volatilization of ammonia in stabilized slow-release nitrogen fertilizer under controlled conditions

“…The application of urea promoted a volatilization of 15.58% N-NH 3 (5.85 mg ring -1 , Table 2). A similar result was observed by Peng et al (2015), who obtained losses of up to 18% for urea. Kiehl and Sengik (1995) found volatilized N-NH 3 loss for urea reaching approximately 16% in sandy soil and 12% in clay soil.…”

Optimum rates of surface‐applied coal char decreased soil ammonia volatilization loss

“…Soils were brought to 10% gravimetric water content (GWC) by applying water and mixing thoroughly, which corresponded to 70 and 50% of field capacity of sandy loam and loam, respectively. Soils were packed in 5‐cm‐diameter clear acrylic columns (Supplemental Figure S4) to a height of 24 cm with a targeted bulk density of 1400 kg m −3 (Peng et al., 2015). A porous ceramic plate (0.1 MPa strength) was inserted in the bottom of the column and topped with Whatman no.…”

“…An attempt was made to collect column leachate on each day after water addition. On each collection date, suction with a 0.25‐horsepower air motor (Model 1603007402, Bluffton Motor Works) was applied to the bottom lid of the column to facilitate drainage of water collected at the bottom of soil column through a porous ceramic plate (Peng et al., 2015). Leachate samples were frozen until analysis for NO 3 –N using a flow injection method (Ahmed et al., 1997).…”

Ammonia volatilization from blends with stabilized and controlled-released urea in the coffee system

“…The coating with polymers caused a decrease in N-NH 3 losses due to reducing the contact of the nutrient inside the granule with the humidity in the air and the soil moisture. This causes a smaller concentration of urea to be hydrolyzed all at once, which reduces the accumulation of N-NH 4 + in the soil, thereby reducing the risk of forming N-NH 3 (Peng et al, 2015).…”