Central African Republic - Intensive open fish farming systems final location: Nile Tilapia

Vector polygon geometry features representing zones with high potential for intensive tilapia farming using cages in water bodies. Produced under the scope of FAO’s Hand-in-Hand Initiative, Geographical Information Systems - Multi-criteria Decision Analysis (GIS-MCDA) suitability assessment. Intensive systems are characterized by high densities and artificial feed input. The score is achieved by processing sub-model outputs characterizing biophysical, infrastructure, and demand factors

Criteria:

a. Market accessibility (large urban areas).

b. Crop input (CropAggGAEZ) availability of agricultural by-products.

c. Livestock input (weighted animal density aggregation) availability of livestock byproducts.

d. Accessibility to ports - considers that high quality/performance tilapia feed is still imported.

e. Tilapia potential yield.

The location score is a simple arithmetic weighted sum of normalized/scaled grids (0 to 100): (“Accessibility MajorUrbanAreas” X 0.40) + (“CropsInput” X 0.15) + (“LivestockInput” X 0.15) + ("Accessibility Ports" X 0.15) + (Tilapia Yield x 0.15)

Constraints:

a. Protected areas.

The Global Surface Water seasonality (seasonality = 12 months) to identify permanent water. Based on the literature the minimum area considered for tilapia cage farming is 5 acres. The final zoning follows the approach:

1. Clipping - Location score mapping is clipped using a 1km buffer from permanent waters with >5ac area polygon layer.

2. Zonal statistics extracted with the maximum (max) score value from the grid layer to the buffer layer polygons.

3. The polygons are selected and displayed for the top 95th percentile.