Submitted to: Soil and Water Conservation Society Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 4/12/2007
Publication Date: 7/21/2007
Citation: Anguelov, G., Kercheva, M., Koleva, V., Stoicheva, D., Delgado, J.A. 2007. Nitrogen leaching on Fluvisols under vegetable cropping system: An assessment with the NLEAP model in Southern Bulgaria. Soil and Water Conservation Society Proceedings. Annual Meeting Abstract. Tampa, FL July 21-25-2007. p. 71.
Technical Abstract: The main mechanism for nitrogen (N) losses in shallow vegetable rooted crops grown in irrigated sandy soils is nitrate-nitrogen (NO3-N) leaching. There is the need to calibrate and validate quick assessment tools to evaluate the effect of best management practices (BMP) for irrigated vegetable cropping systems on Fluvisols in Southern Bulgaria. Simulation models such as NLEAP (Shaffer et al., 1991) are capable of integrating soil and climate information with management practices to evaluate the effect of BMPs on nitrogen use efficiencies (Delgado, 2001). We are going to present experimental data and NLEAP model simulations of a vegetable cropping system on irrigated Fluvisols in Bulgaria. NLEAP was used to evaluate the effects of two fertilizers (ammonium nitrate and urea); two methods of application (single preplant vs split) and crop intensity (two vegetable crops grown during two years vs three vegetable crops grown during two years). Additionally, three N rates; the recommended agronomic N-rate, 50% below the recommended N rate, and 50% above the recommended N rate were studied. Nitrate leaching was monitored with a lysimeter and N was measured in plant, soil and water compartments. NLEAP was calibrated and tested to simulate NO3-N leaching out of the top 0-1.0 m profile. Preliminary results show that NLEAP was able to simulate the effects of BMPs on drainage water and NO3-N leaching. We will present the results from these studies and the evaluation of NLEAP as a potential quick tool to assess BMPs for Fluvisols in Southern Bulgaria.