Antar A. S. and M.Y.M. Awad( 2014). Impact of Nitrogen Sources on Nitrate Losses into Tile Drain in Clay Soil under Sugar
Beet Crop
Middle East Journal of Agriculture Research, 3(4): 936-942, 2014 ISSN 2077-4605
Abstract: A field study was conducted at the Experimental Farm of Sakha Agriculture Research Station (31°07′ 33″ N latitude and 30°57′ 53″ E longitude) during the winter seasons (2012/13 and 2013/14) to evaluate the impact of applied different N-fertilizer sources (urea, ammonium nitrate, ammonia gas at 100 kg N fed-1, farm manure (10 m3 fed-1 )+ urea or ammonium nitrate at 50 kg N/fed on nitrate losses and sugar beet yields and its N-uptake. Results indicate that the water tables level nearly the same in all treatments. Drains discharge were higher with planting irrigations than the other irrigations. Total cumulative drains discharge varied from 515.17 to 525.68 m3fed.-1. Nitrate concentrations were low before fertilizer application and increased after fertilizer
application, then reduced with the latest irrigations. The highest concentration of NO- 3 in drainage water were found with 100 kg N fed-1 ammonium nitrate (48.55 ppm) and 100 kg N fed-1 urea (43.51 pmm) while the lowest one was 100 kg fed-1 ammonia gas (23.18 pmm) in the first season. The same trend was observed in the second season. Ammonium nitrate at 100 kg Nfed-1 increase total losses of NO- 3 (kg Fed-1) (25.30and 25.87) followed by urea (22.65 and 21.98) more than the other treatments in both seasons respectively. A significant differences in sugar beet roots yield between treatments were found. Aammonia gas was the best one in 1st and 2nd seasons followed by farm manure + urea treatment in root yield and its N-uptake.
Keywords: (Losses, tile drainage, N-fertilizer, ammonia gas, farm manure, clay soil, sugar beet.)
