Volatilization of N-NH3 influenced by urea application forms, residue management and soil type in lab conditions

Ciência Rural

Sangoi, Luís¹  Rampazzo, Clair¹  Lech, Vanderlei Adilson¹  Ernani, Paulo Roberto¹ 

[1]Universidade do Estado de Santa Catarina, Lages

关键词: ammonia volatilization;    urea;    soil texture;   

DOI  :  10.1590/S0103-84782003000400016

学科分类：农业科学（综合）

来源: Universidade Federal de Santa Maria * Centro de Ciencias Rurais

【 摘 要 】

Ammonia volatilization is the main N loss responsible for the low efficiency of urea applied to the soil surface. This experiment evaluated the effects of urea application method and black oat residue management on ammonia volatilization in two soils with different organic matter and clay contents under laboratory conditions. Two trials were conducted using an UDULT (UD) and a PSAMENT (PS), containing 520 and 50g kg-1 of clay, respectively. Treatments included a factorial combination of three methods of nitrogen application (without N, urea broadcast on the soil surface and soil incorporated urea) and three oat residue management forms (without straw, superficial straw and soil incorporated straw). Rates equivalent to 4.0mg ha-1 of oat straw and 255kg ha-1 of N were used. The experiment was set using PVC columns as experimental units. Each column had 1.47kg of UD and 2.1kg of PS soil. The columns were hermetically sealed and connected through a plastic hose to glass collectors containing sulfuric acid. N-NH3 volatilization was estimated in different days after treatment addition. Urea applied at the soil surface caused higher volatilization of N-NH3 than urea incorporated, in both soils. In the sandy soil, volatilization was highest when oat straw was kept at the soil surface, regardless of the urea application method. N-NH3 volatilization was numerically greater and faster in the soil with lower clay and organic matter content, probably due to a small cation exchange capacity.

【 授权许可】

CC BY-NC