Agriculture intensification and ecologically sustainable land use in Niger: a case study of evolution of intensive systems with supplementary irrigation

In Niger, a breakdown of the bush-fallow system, low crop yields and reduced availability of communal land have resulted from increasing population pressure. Agricultural intensification is critical to the future development of the region. Intensification of agricultural production in Niger must include adoption of sustainable yield increasing technologies, fertilizer use, supplementary irrigation and/or water conservation, high yielding cultivars and improved crop management practices. On-farm constraints analysis of crop productivity and technologies assessment was carried out in two irrigated perimeters: the Konni surface irrigation and the Djirataoua deep well system where supplemental irrigation is provided to rainy season crops in the event of long dry spells, and full irrigation is supplied to dry season crops. Konni is located in southern Niger, approximately 13 degrees 48'0"N, 5 degrees 15'0"E at approximately 257 m altitude; Djirataoua is located further east, approximately 13 degrees 20'0"N, 7 degrees 7'60"E at approximately 368 m altitude, near Maradi, which is located at approximately 13 degrees 28'60"N, 7 degrees 5'60"E, approximately 376 m altitude. In both the Konni and Djirataoua irrigation systems, use of supplementary irrigation has enhanced cropping intensity and crop productivity per unit area (yield) while generating greater employment opportunity. Analysis of long-term crop productivity trends during 1980-1997 revealed that sustainability of gained productivity is possible through agricultural intensification over years without any sign of productivity decline. These results show that the use of agriculture intensification technologies plays a crucial role in sustainable, increased crop production in the Sahel. The results of our diagnostic survey in these two perimeters showed that the major constraints to increased productivity are low fertilizer use, poor nutrient use efficiency, the lack of well adapted, high yielding varieties or hybrids, poor crop establishment and plant protection in farmers fields, and inappropriate input and output pricing. On-farm evaluation of the improved technologies, namely improved varieties or hybrids and optimal fertilizer use with optimal supplementary irrigation, resulted in a 35% increase in grain yields at the farm level. The lesson learned from this study is that developing sustainable agricultural production systems in Niger with higher yields, or production per unit area, than present-day yields depends upon supplementary irrigation if or where potential exists, and upon promotion of fertilizer use, high yielding cultivars and other innovative production technologies. This strategy will help reduce frequency and intensity of food shortages and will ultimately help reduce the incidence of poverty and starvation in Niger.