Nitrogen Leaching and Denitrification in Continuous Corn as Related to Residue Management and Nitrogen Fertilization

Drenagem interna e lixiviação de nitrato em um latossolo sob sucessão milho-braquiária-milho, com diferentes doses de nitrogênio

“…Esse autor encontrou um máximo de lixiviação de N de 1,5 kg ha -1 , a 0,50 m, no período de 20 a 128 DAE, aplicando 25 kg ha -1 de N em semeadura e 50 kg ha -1 de N em cobertura. Já Gollany et al (2005) …”

Seasonal temperatures have more influence than nitrogen fertilizer rates on cucumber yield and nitrogen uptake in a double cropping system

“…It was comparable with N fertilization in Valencian Community region areas with intensive agricultural production in Spain, in which nitrogen fertilization in pepper and tomato cropping system could reach to 1030 and 940 kg N ha À1 , respectively (Ramos et al, 2002). Fertilizer N use efficiency in intensively managed greenhouse vegetable systems can be less than 10% using conventional management practices (Zhu et al, 2005), consequently large amounts of unused nitrogen are released to the environment through nitrate leaching, denitrification and NH 3 volatilization (Cabrera et al, 1993;Cabrera and Chiang, 1994;Fox et al, 1996;Gollany et al, 2004;Ramos et al, 2002). For example, nitrate-N concentrations in shallow wells around greenhouses in Huimin, Shandong, ranged from 9 to 274 mg N L À1 , with 99% of surveyed wells exceeding the USEPA limit of 10 mg N L À1 , more than half of the samples (53%) exceeding 50 mg N L À1 , and 26% exceeding 100 mg N L À1 (Ju et al, 2006).…”

Internal drainage and nitrate leaching in a corn-black oat-corn succession with two split nitrogen applications

“…In addition, maintaining the ground covered with plant material is important since plants constitute the only safe way of recycling nitrates. In studies on N fertilization (20 and 200 kg N ha -1 ) in corn with two types of management (harvested residues or returned residues) was verified that, during 30 years of simulation, nitrate losses by leaching were higher in plots where the residues were removed from the soil, when compared with plots where residues were returned to the soil (Gollany et al, 2005). However, did not find significant differences between cultivation systems or between split N applications, for the amount of nitrate found below 1.2 m, during two years of experimentation (AlKaisi & Licht, 2004).…”