Abstract
Smallholder agriculture is a major source of income and food for
developing nations. With more frequent drought and increasing scarcity
of arable land, land use planning can be used to better allocate land
resources to support regional agricultural activity. To support this
objective, we used the Land Capability Classification (LCC) system to
map the basic limitations to agricultural use of land. The LCC is a
stepwise hierarchical land assessment system that can be used to
understand factors that limit land use potential. We carried out our
assessment in the Dosso region of Niger. Using two public soil data
sets, Food and Agriculture Organization Harmonized World Soil Database
and International Soil Reference and Information Center (ISRIC)
SoilGrids, and a modified version of the LCC, we developed 250 m gridded
maps of LCC values across the region. To validate the LCC maps, we
interpolated soil physical data from 1308 field sites in the Dosso
region and created LCC maps based on these interpolated data. We find
that across the region, land is very severely limited for agricultural
use by available water-holding capacity (AWC) which limits dry season
agricultural potential, especially without irrigation, and requires more
frequent irrigation where supplemental water is available. If the AWC
limitation is removed in the LCC algorithm (i.e. simulating the use of
sufficient irrigation or a much higher and more evenly distributed
rainfall than is received by the Dosso region), the dominant regional
limitations become less severe and more spatially varied.