Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Suède → Environmental modeling study of water adequacy and yield from an irrigated rice field in Mali

Royal Institute of Technology (KTH) 2015

Environmental modeling study of water adequacy and yield from an irrigated rice field in Mali

Tedla, Amhagiyorgis

Titre : Environmental modeling study of water adequacy and yield from an irrigated rice field in Mali

Auteur : Tedla, Amhagiyorgis

Université de soutenance : Royal Institute of Technology (KTH)

Grade : Master - Water System Technology 2015

Résumé
A process oriented modeling of an irrigated rice field in a semi arid area of Mali has been done with the help of computational tool CoupModel. The model has been used to simulate two levels of irrigation rates, in an attempt to test and see adequacy of a recommended irrigation rate and its environmental impact over the current management. A simpler simulation to represent less water demanding crops like sorghum or millet has also been done to indicate extent of the excess water and as alternative crop cultivation. Important processes and parameters to represent a rice cropping system have been identified and simulation was run for a 12 year period. Results show an irrigation amount of 916 mm delivers an overall 6 % increased yield. Results from the reduced irrigation also show a better output in surface runoff, nitrogen leaching and uptake, photosynthetic water use efficiency and fertilizer efficiency. Soil nitrogen and carbon storage shows nearly the same trend. Only nitrous oxide (N2O) emission rate increased by 13 % in the case of reduced irrigation. Simulation done for the other crops also shows a reasonable yield of sorghum or millet can be obtained with 46 % of water used for current rice irrigation.

Mots clés : CoupModel, Yield, Irrigation rate, Evapotranspiration, Runoff, Nitrogen uptake and leaching

Présentation

Version intégrale (1,64 Mb)

Page publiée le 5 février 2016, mise à jour le 4 août 2018