River Flood variability and agricultural options in the Inner Niger Delta: cultivation of rice or bourgou?

Abstract

The Republic of Guinea is planning to build the Fomi dam in the Niger basin. It will be a dam with an embankment of 42 m high, for a reservoir over 507 km² and a volume of about 6.2 billion m3. This study focuses on the ability of irrigation to offset losses undergone by breeders and fishermen in the delta, due to the impoundment of the Fomi dam. Data from 70 small village irrigation schemes located in the Mopti region were used to compare the average income of a hectare of irrigated rice to that of a bourgou field, a grassy vegetation formation dominated by Echinochloa stagnina, known locally as "bourgou". The results show that irrigated rice cultivation and exploitation of natural bourgou fields are both profitable. Currently in the delta, the average annual income is 440 109 FCFA/ha. The annual income of a natural bourgou field is estimated at 341 320 FCFA/ha. However, in addition to the economic benefits of bourgou, bourgou fields favour the devlopment of aquatic fauna. However, irrigated rice is slightly more profitable than growing bourgou. Similarly, the sale of dry matter of a regenerated bourgou field proved less profitable than the sale of paddy rice.