A comparison of approaches to regional land use capability analysis for agricultural land planning

Authors: IPPOLITO, T - University Of Colorado; Herrick, Jeffrey - Jeff; DOSSA, E - Non ARS Employee; GARBA, M - Non ARS Employee; OUTTARA, M - Non ARS Employee; SINGH, U - Non ARS Employee; STEWART, Z - Kansas State University; PRASAAD, V - Kansas State University; NEFF, J - University Of Colorado

Submitted to: Land
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/22/2021
Publication Date: 4/24/2021
Citation: Ippolito, T., Herrick, J.E., Dossa, E.J., Garba, M., Outtara, M., Singh, U., Stewart, Z., Prasaad, V., Neff, J. 2021. A comparison of approaches to regional land use capability analysis for agricultural land planning. Land. 10. https://doi.org/10.3390/land10050458.
DOI: https://doi.org/10.3390/land10050458

Interpretive Summary: In the face of increasing drought prevalence, land use analysis can be used to spatially assess agricultural suitability using a variety of physical factors. A simple, but well used approach to land use planning is the Land Capability Classification system (LCC). LCC is a land potential evaluation system that identifies land suitable to cropping or grazing land use and the associated physical limitations to productivity risks of degradation and has been used to identify and implement management interventions to improve agricultural productivity and sustainability. Using LCC provides the flexibility to assess constraints to agriculture at any scale and in any location where sufficient data is available. Using two public soil data sets and a modified version of LCC, we developed 250m gridded maps of LCC values across the Dosso region in Niger. We found 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.

Technical 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 system (LCC) 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 -- a region currently being evaluated for agricultural intensification by international development organizations and the Niger government. Using two public soil data sets, FAO Harmonized World Soil Database and ISRIC SoilGrids, and a modified version of LCC, we developed 250m 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.