Nitrous Oxide Emissions from Agricultural Toposequences in Alberta and Saskatchewan

摘要: Nitrous oxide fluxes from soils are inherently variable in time and space. An improved understanding of this variability is needed to make accurate estimates N 2 O at a regional scale. The objectives work were (i) characterize the influence soillandscape combinations application rates on emissions (ii) determine contribution these influences estimation field We used static chambers gas chromatography methods measure collected ancillary data (mineral N, water soluble C, soil content, temperature) Canada Mundare (AB) aspen parkland ecoregion Swift Current (SK) short-grass prairie ecoregion. At Mundare, measurements taken 1995 1996 by landscape position land use. Current, 1999 2000 rate. affected but pattern varied seasonally. During 46-d period summer 1995, flux 430 g O-N ha -1 measured backslope was greater than 60 average shoulder depressional areas. changed during 43-d spring thaw when areas greatest (1710 ). natural small. emission similar that an order magnitude larger. topography Fluxes receiving 110 kg (3140 Use area fraction occupied each calculate increased scale five out six cases. Further research landscapes should help elucidate factors controlling pedon thus translate into scales.