Figure 1.

Map of Antananarivo with its 192 districts ("fonkontany" in Malagasy) and rice fields located by satellite images. A comparison of satellite images in different seasons made it possible to locate the rice fields (in light grey) and to differentiate them from the other types of vegetation (in white: bare soil, vegetation, other crops). Districts are delimited as indicated on the map. For each district, rice field index was calculated by dividing the area under rice by the area of the entire district.