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

Accueil du site → Master → Ethiopie → Agricutltural Drought Assessment Using Remote Sensing and Gis Techinques

Addis Ababa& University (2010)

Agricutltural Drought Assessment Using Remote Sensing and Gis Techinques

Legesse, Gizachew

Titre : Agricutltural Drought Assessment Using Remote Sensing and Gis Techinques

Auteur : Legesse, Gizachew

Université de soutenance : Addis Ababa University

Grade : Masters of Science in Remote Sensing and Geographic Information System (GIS) 2010

Résumé partiel
Climate has always been a dynamic entity affecting natural systems through the consequence of its variability and change. Agriculture is the most vulnerable and sensitive sector that is seriously affected by the impact of climate variability and change, which is usually manifested through rainfall variability and recurrent drought. In dryland semiarid areas of Ethiopia, including large part of East Shewa zone, agricultural drought and crop failure have been common, and farmers inhabiting the area experience extreme temporal and spatial variability of rainfall in cropping season with frequent and longer dry spells. This makes them vulnerable to the risk of agricultural drought. Thus, in order to adapt and/or mitigate the impact of agricultural drought, agricultural drought assessment has to form one dimension of research to be done whereas the use of remote sensing and GIS techniques provides wide scope in drought risk detection and mapping. Consequently, this study was conducted in East Shewa zone with the objective of assessing agricultural drought risk and preparing agricultural drought risk zone map using satellite data. To assess and examine spatiotemporal variation of seasonal agricultural drought patterns and severity, three drought indices namely, Water requirement satisfaction index (WRSI), Standard precipitation index (SPI) and NDVI anomaly are applied. A time series advanced very high resolution radiometer (AVHRR) NDVI and rainfall estimate (REF) satellite data for the years 1996- 2008 were utilized as input data for the indices while grain yield data was used to validate the strength of indices in explaining the impact of agricultural drought. The result derived from indices for the study period has shown that the 2000 to 2005 cropping seasons experienced enhanced agricultural drought with observed spatial difference in severity level within East Shewa zone. However, the severity level was higher in 2000 and 2002 cropping seasons whereas 2002 being the most severe of all. The impact of agricultural drought on crop production was measured through estimation of yield reduction.

Présentation

Version intégrale (2,72 Mb)

Page publiée le 29 décembre 2011, mise à jour le 8 avril 2020