Nitrous oxide and dinitrogen emissions from soil under different water regimes and straw amendment

Citation
Z. Cai et al., Nitrous oxide and dinitrogen emissions from soil under different water regimes and straw amendment, CHEMOSPHERE, 42(2), 2001, pp. 113-121
Citations number
41
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Environment/Ecology
Journal title
CHEMOSPHERE
ISSN journal
0045-6535 → ACNP
Volume
42
Issue
2
Year of publication
2001
Pages
113 - 121
Database
ISI
SICI code
0045-6535(200101)42:2<113:NOADEF>2.0.ZU;2-Y
Abstract
In a laboratory study, soil amended with and without wheat straw (2.8 g kg( -1) soil) was incubated under 70% water holding capacity (WHC), continuousl y flooded and flooded/drained cycle conditions at 30 degrees C for 51 days. Dinitrogen and N2O evolution and ammonia volatilisation were measured duri ng the incubation. Extractable NH4+-N and NO3--N were determined at the end of the incubation. Entrapped N-2, N2O, and dissolved NH4+-N and NO3--N in drainage water were measured in the flooded/drained cycle treatment when th e floodwater was drained. The results indicated that N loss through ammonia volatilisation was undetected in all treatments due to the low soil pH val ue (pH(H2O) = 5.87) and no air movement. The recovery of urea-N-15 as N-2 w as lowest in the continuously flooded treatments (0.75% and 0.96% with and without straw amendment, respectively), highest in the 70% WHC treatments ( 5.65% and 4.41%, respectively), and intermediate in the flooded/drained cyc le treatments (1.79% and 2.65%, respectively). The recovery of urea-N-15 as N2O was in the same order as that of N-2, negligible in the continuously f looded treatments, 0.01% and 0.07% in the flooded/drained cycle treatments, and 1.29% and 2.23% in the 70% WHC treatments, respectively. Peak N2O evol ution rates were observed after the floodwater was drained but no substanti al evolution was found after the soil was reflooded following drained perio ds. However, peak N-2 evolution rates were observed after the onset of both drainage and re-flooding. Considerable quantities of N-2 but no detectable N2O were entrapped in the flooded soil. (C) 2000 Elsevier Science Ltd. All rights reserved.