Digital Soil Mapping and GIS-based Land Evaluation for Rice Suitability in Kilombero Valley, Tanzania

A Graduate Defense Seminar will be presented by Boniface H.J. Massawe, PhD Candidate on Thursday (5/14) at 10:00 a.m. in 245 Kottman Hall. Boniface will present Digital Soil Mapping and GIS-based Land Evaluation for Rice Suitability in Kilombero Valley, Tanzania.

A GIS-based multi-criteria land evaluation was performed in Kilombero Valley, Tanzania in order to avail decision makers and farmers with evidence based decision tool for improved and sustainable rice production. Five most important criteria for rice production in the area were identified through literature search and discussion with local agronomists and farmers. These were soil properties, surface water resources, accessibility, distance to market, and topography. Distance metrics were used to numerically classify and cluster soil profile information gathered through field and lab works. Decision tree based algorithms were employed to digitally predict spatial distribution of the numerically classified soil clusters using environmental correlates derived from digital elevation model, satellite image and a legacy soil map. Spatial information for other criteria were generated through on-screen digitization, mapping of field recorded data, and derivations from digital elevation models. Analytical hierarchy process (AHP) method was used to score the criteria whereby surface water resource criterion scored the highest and distance to market scored the least. The multi-criteria land evaluation results showed that about 8% of the study area was classified as having low suitability for rice production while only 2% was highly suitable. The majority of the area (about 89%) was classified as having medium suitability for rice production.