Télédétection et ressources en eau/Remote sensing and water resources
115
Assessment of irrigation potential in Africa
Arc-Info: a tool for the computation of the irrigation water
requirements at continental level
RÉSUMÉ
Dans le cadre de l'estimation du potentiel d'irrigation pour l'Afrique, la FAO a adopté en
1995 une approche par bassin versant. L'intégration des données sur les ressources en
eau et les terres aptes à l'irrigation est réalisée sur chacun de ces bassins en fonction des
besoins en eau d'irrigation. Arc-Info est l'outil utilisé pour définir les unités géographiques
de calcul, qui sont homogènes en termes de précipitations moyennes, d'évapotranspiration
potentielle, de calendrier et d'intensité de culture, et d'efficience de l'irrigation. En
associant les informations sur les besoins en eau d'irrigation bruts, les superficies de sols
adaptés à l’irrigation et les disponibilités d’eau par bassin, on peut estimer le potentiel
réel d’irrigation en Afrique.
ABSTRACT
In 1995, FAO undertook a study to assess the irrigation potential of Africa, based on a
river basin appoach. To integrate information on land and water at the river basin level,
knowledge of irrigation water requirements per unit of land area is necessary. Arc-Info
was used to define the geographical computation units, which are homogeneous regarding
average rainfall, potential evapotranspiration, cropping pattern (calendar, intensity) and
irrigation efficiency. Combining information on gross irrigation water requirements, area
of soils suitable for irrigation and available water resources by basin eventually results in
an estimation of the physical irrigation potential for Africa.
INTRODUCTION
There is growing concern over food security in Africa and especially sub-Saharan Africa. While the
aggregate food supply/demand picture is relatively good, there will be a worsening in food security in
sub-Saharan Africa, and cereal imports are projected to triple between 1990 and 2020, for which it will
not be able to pay. Although the food situation is not as severe in North Africa, projections also
indicate increasing cereal imports to 2020. To tackle this worsening situation, an increase in food
production in Africa is necessary, and irrigation is one important and, in many areas, indispensable
input to obtain this increase.
Mathieu Bousquet, Jean-Marc Faurès, Karen Frenken, Luc Verelst
Land and Water Development Division, FAO, Rome, Italy
115
Assessment of irrigation potential in Africa
Arc-Info: a tool for the computation of the irrigation water
requirements at continental level
RÉSUMÉ
Dans le cadre de l'estimation du potentiel d'irrigation pour l'Afrique, la FAO a adopté en
1995 une approche par bassin versant. L'intégration des données sur les ressources en
eau et les terres aptes à l'irrigation est réalisée sur chacun de ces bassins en fonction des
besoins en eau d'irrigation. Arc-Info est l'outil utilisé pour définir les unités géographiques
de calcul, qui sont homogènes en termes de précipitations moyennes, d'évapotranspiration
potentielle, de calendrier et d'intensité de culture, et d'efficience de l'irrigation. En
associant les informations sur les besoins en eau d'irrigation bruts, les superficies de sols
adaptés à l’irrigation et les disponibilités d’eau par bassin, on peut estimer le potentiel
réel d’irrigation en Afrique.
ABSTRACT
In 1995, FAO undertook a study to assess the irrigation potential of Africa, based on a
river basin appoach. To integrate information on land and water at the river basin level,
knowledge of irrigation water requirements per unit of land area is necessary. Arc-Info
was used to define the geographical computation units, which are homogeneous regarding
average rainfall, potential evapotranspiration, cropping pattern (calendar, intensity) and
irrigation efficiency. Combining information on gross irrigation water requirements, area
of soils suitable for irrigation and available water resources by basin eventually results in
an estimation of the physical irrigation potential for Africa.
INTRODUCTION
There is growing concern over food security in Africa and especially sub-Saharan Africa. While the
aggregate food supply/demand picture is relatively good, there will be a worsening in food security in
sub-Saharan Africa, and cereal imports are projected to triple between 1990 and 2020, for which it will
not be able to pay. Although the food situation is not as severe in North Africa, projections also
indicate increasing cereal imports to 2020. To tackle this worsening situation, an increase in food
production in Africa is necessary, and irrigation is one important and, in many areas, indispensable
input to obtain this increase.
Mathieu Bousquet, Jean-Marc Faurès, Karen Frenken, Luc Verelst
Land and Water Development Division, FAO, Rome, Italy