Land evaluation for alternative crops of alfalfa using GIS in south Hail, Saudi Arabia

Abstract EN

The assessment of soil suitability for sustainable intensive agriculture is important for the selection of land suitable for agricultural production with the least economic and environmental costs.

This study was directed to evaluate agricultural soil suitability in the south of Hail province, Saudi Arabia to suggest alternative crops of alfalfa using the Agricultural Land Evaluation System for arid regions (ALES-Arid) model and Geographic Information System (GIS).

The study area covers about 77558 ha and 111 soil samples were collected from 37 profiles and 37 groundwater samples were analyzed for physical, chemical and fertility properties.

To evaluate land suitability for selected crops, the FAO guideline was used and also to analyze and map soils within the study area, the GIS was employed.

The main research goals were to characterize the soil and water resources of the study area, in order to plan the best alternative crops of alfalfa using land evaluation facilities for different purposes (capability and suitability).

The results indicated that the soils of the area are characterized by sandy loam texture, low fertility, low total carbonate and most of the area have moderate to high salinity soil.

Capability classes of the area are C3 and C4 which covers about 89.19% and 10.81% of the total area, respectively.

The most fertile classes were situated in C2 and C3 which covers 37.84 and 40.54% of the area with phosphorus and potassium limitation.

The land suitability results show that 99.68, 97.18 and 85.37% of the area is classified as S1 (highly suitable) for wheat, barley and alfalfa, respectively; while 98.91% of the area is classified as S3 (marginally suitable) for maize.

From the obtained data, growers are advised to cultivate barley or wheat in winter and maize in summer instead of alfalfa, in order to save irrigation water.

This is also because the expected productivity of either wheat or barley is high.

It is important for decision makers to determine the best way of using land for agricultural purposes, since it serves as a decision and planning support.