Gaseous nitrogen losses from soils under sugar cane in Mauritius
| MSI99P3211 | |
| Ng Kee Kwong, K. F. Bholah, A. Veerapen, S. | |
| Gaseous nitrogen losses from soils under sugar cane in Mauritius | |
| Periodical article | |
| 1999 | |
| Proc. int. Soc. Sug. Cane Technol. | |
| 23(2): 70-79 | |
| Paper presented at the ISSCT Congress, 22-26 February 1999, New Delhi, India | |
| En | |
| En Fr | |
| Prompted by environmental and agronomic concerns, the emission of nitrous oxide (N2O) and nitrogen (n2) gases from soils under sugarcane was monitored by the acetylene inhibition technique at 4 sites fertilized with and without 140 kg N ha -1 at 4 sites fertilized with and without 140 kg N ha -1. The data obtained showed that the rates of N2O/N2 emission from the soils cannot be predicted by any single soil variable. Moreover, in spite of site to site variabilities, the temporal pattern of the gaseous N emissions invariably showed a base level emission rate ranging 30 to 50 g N ha -1 d -1 with the N2O/N2 pulse rising 2 to 3 times above the background level during the high rainfall season (December to April). Upon N fertilizer application, large pulses of gaseous N emission with the flux attaining a peak of 300 g N ha -1 d -1 were only observed at belle rive while at the 3 other sites (Réduit, Union Park and Pamplemousses), the rates of gaseous N loss from soils were hardly altered by fertilizer application. The results showed that gaseous losses of fertilizer N were of agronomic significance only at Belle Rive where 16 per cent of the 140 kg N ha -1 applied escaped to the atmosphere over the 1996/97 sugarcane growing season as compated to less than 3 per cent at 3 other sites. Soil wetness was the most important factor controlling hoth the size of the N2O/N2 flux and the ration N2O: N2 emitted from the soils. Production of N2 gas was of significance only at belle Rive where more than 80per cent of the soil pore space was water filled for frequent prolonged periods. Though the present study showed that gaseous losses of fertilizer N may in general not be of agronomic or economic relevance, the magnitude of total N2O emissions from sugarcane soils which ranged from 16 to 20 kg N ha -1 is of concern from the environment point of view. | |
| SUGARCANE PLANT NUTRITION GASEOUS NITROGEN NITROGEN LOSSES SOILS | |
| MAURITIUS | |
| Sugarcane: Soils and plant nutrition | |
| Fertilization: Nitrogen | |
| 1999-04-29 | |
| En | |
| LIST | |
| CHEM |