Pedosphere 22(6): 764--775, 2012
ISSN 1002-0160/CN 32-1315/P
©2012 Soil Science Society of China
Published by Elsevier B.V. and Science Press
| Short-term responses of nitrous oxide emissions and concentration profiles to fertilization and irrigation in greenhouse vegetable cultivation |
S. RIYA1, MIN Ju2, ZHOU Sheng3 , SHI Wei-Ming2 and M. HOSOMI3 |
1 Graduate School of Engineering, Tokyo University of Agriculture and Technology, Tokyo 184-8588 (Japan);
2 State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China);
3 Institute of Engineering, Tokyo University of Agriculture and Technology, Tokyo 184-8588 (Japan) |
| ABSTRACT |
| In vegetable cultivation, the majority of N2O emissions occur after fertilization; it is therefore important to understand any factors contributing to this process. An experiment was conducted to investigate short-term N2O dynamics following topdressing in a greenhouse vegetable field in South China. During two topdressing processes, three different urea-N treatments with irrigation were conducted in May and June in a tomato (Lycopersicum esculentum) cultivation. The N2O fluxes, soil concentration profiles and soil environments at the 0-60 cm depths at 10 cm intervals were measured both immediately prior to and 5 days after topdressing. The N2O fluxes before topdressing ranged from 6.7±2.1 to 55.0±28.8 μg N m-2 h-1; even higher numbers were recorded in highly fertilized plots. The NO3--N accumulation in the soil caused by vegetable cultivation during the 5 years prior to the start of the experiment, resulted in high background N2O fluxes. One day after topdressing (1 DAT) in May and June, N2O fluxes increased, which coincided with sharp increases in soil N2O concentrations at depths of 2.5 and 15 cm and in NO3--N and NH4+-N contents at depths of 0-20 cm. From 1 to 5 DAT, fluctuations in the N2O fluxes did not harmonize with the N2O concentrations at a depth of 2.5 cm, which was attributed to different gas diffusion rates at depths of 0-10 cm. These results suggested that surface soil N and environmental conditions were crucial for determining the short-term N2O ebullitions during topdressing in greenhouse vegetable cultivation. |
| Key Words: nitrogen application, N2O, soil profile, topdressing, vegetable field |
| Citation: Riya, S., Min, J., Zhou, S., Shi, W. M. and Hosomi, M. 2012. Short-term responses of nitrous oxide emissions and concentration profiles to fertilization and irrigation in greenhouse vegetable cultivation. Pedosphere. 22(6): 764-775. |
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