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Gaseous Carbon and Nitrogen Emissions in Organic Agriculture in Northern Oman
| Content Provider | Semantic Scholar |
|---|---|
| Author | Siegfried, Konrad Dietz, Herbert Schlecht, Eva Buerkert, Andreas |
| Copyright Year | 2008 |
| Abstract | Information about gaseous losses of carbon (C) and nitrogen (N) in irrigated organic agriculture in northern Oman is scarce. To fill this gap of knowledge a field experiment was carried out in an experimental farm near Sohar, during which applications of two bovine manure types (a C/N ratio of 39 at high fibre content and a C/N ratio of 31 with a low fibre content) and a control treatment (mineral fertilisers with equivalent levels of N and P and K) were factorially combined with two crop rotations comprising cauliflower (Brassica oleracea) and carrot (Daucus carota subsp. sativus) each preceded by a crop of radish (Raphanus sativus). Concentrations of soil-surface emitted NH3, N2O, CO2 and CH4 were determined using an INNOVA photo-acoustic infrared multi-gas monitor within a closed chamber system and acumulative leaching losses through cartridges filled with cation/anion-exchange resins. Cumulative gas emissions during a 90 day cropping period attained a total of 14 kg Nha-1 (68 % NH3, 32% N2O) and 2,254 kg C ha-1 (98 % CO2, 2% CH4) for plots treated with organic manure of high C/N and high fibre as compared to equal 14 kgN ha-1 and 1,889 kgC ha-1 for plots treated with organic manure of low C/N and low fibre content. Emission rates declined between irrigation events, most likely due to decreasing soil moisture. The significant effect of time on gaseous emissions determined for N2O (p = 0.0266), CO2 (p = 0.001) and CH4 (p = 0.001) was likely due to changing soil moisture and relative humidity. Cumulative N-leaching was with a total 13 kg ha-1 higher on plots amended with organic manure of high C/N and high fibre in comparison to leaching losses of 6 kg N ha-1 on plots with organic manure of low C/N and low fibre content. Cumulative N leaching losses were higher on plots planted with cauliflower than on carrot plots. This may be due to differences in the rooting system and uptake dynamics of both crops. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www.tropentag.de/2008/abstracts/links/Buerkert_Rmd9ZwUa.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |