Affiliation:
1. IAC, Brasil
2. USP, Brasil
3. IAC
4. APTA, Brasil
5. IAC; Usina São João, Brasil
Abstract
Legal restrictions from burning sugarcane prior to harvest are causing a sharp increase in acreage which is harvested as green cane. The presence of a thick sugarcane trash mulch left after harvest makes it difficult to incorporate fertilisers in the soil. Since large losses of ammonia may occur when urea is surface applied to trash, it is important to find ways to improve urea-N use efficiency. The urease inhibitor NBPT slows down urea hydrolysis and thus may help decrease ammonia losses. Ammonia traps were set up in seven sugarcane fields covered with trash and fertilised with ammonium sulfate or ammonium nitrate, urea, and NBPT-treated urea. All N fertilisers were surface-applied at rates of 80 or 100 kg N ha-1. Very little N was lost when ammonium nitrate or ammonium sulfate were used. However, volatilisation losses as ammonia from the urea treatments varied from 1% (rainy days after fertilisation) to 25% of the applied N. The percentage of reduction in volatilisation due to NBPT application ranged from 15% to 78% depending on the weather conditions during the days following application of N. Addition of NBPT to urea helped to control ammonia losses, but the inhibitor was less effective when rain sufficient to incorporate urea into the soil occurred only 10 to 15 days or latter after fertiliser application.
Subject
Agronomy and Crop Science,Animal Science and Zoology
Reference17 articles.
1. Methods of soil analysis: Part 2. Chemical and microbiological properties;BREMNER J.M.,1965
2. Effect of urea placement on crop cycle yields of green trash blanketed sugarcane ratoons;CALCINO D.V.;Proceedings of Australian Society of Sugar Cane Technologists,1995
3. Fruit yield of Valencia sweet orange fertilized with different N sources and the loss of applied N.;CANTARELLA H.;Nutrient Cycling in Agroecosystems,2003
Cited by
157 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献