Assessment of suitable land for surface irrigation using spatial information systems: Case of Bilate River Basin in the Rift Valley Lakes Basin, Ethiopia
Introduction
With a rapid rate of population increase there will be a competition for the limited available resources (water and land), which will result in high pressure on arable land to increase food production. With continuing population growth and limited potential to increase suitable cropland, efficient irrigation becomes an increasingly important tool to ensure sufficient global supply of food in the future (Wichelns and Oster, 2006, Sauer et al., 2010). The shortage of food in Africa continent is ever rising since 2014, reach nearly one-fifth of the population. The weather extremes are one of the factors which play significant role to unsustainable production of cereals (FAO, 2021) through rain fed farming system. As Irrigation a basic strategy to alleviate poverty and hence food security, transforming the rain-fed agricultural system into the combined rain-fed and irrigation agricultural system is believed to be the most prominent way of sustainable development. According to Kadigi et al (2019), it is only six million hectare (4 %) of Sub-Saharan Africa's total cultivated area is irrigated, while this is even lower to 2.08 % of the cultivable land in Ethiopia in 2018 as to World Bank's collection of development indicators compiled from officially recognized sources (Yonas et al 2022).
In Ethiopia, there is no consistent and reliable inventory and well-studied and documented (Belay and Woldeamlak, 2013) with regards to water and irrigations related potentials in the Ethiopian context. MoA (2011) reported about 10–12 % of the total irrigable potentials are under production using traditional and modern irrigation schemes (Haile and Kasa, 2015). According to the World Bank's collection of development indicators compiled from officially recognized sources, Ethiopia's agricultural irrigated land was 2.08 % percent in 2018. Identifying the limited available resource, use of improved irrigation technology and better water resources management have been suggested as mechanisms for increased production. To optimize the agricultural production, knowing the available land for irrigation is mandatory.
The Bilate river basin is among the highly populated with erratic rainfall basins of Ethiopia, that relays on the traditional method of food production using rain fed agriculture. As a result of that, the people in some parts of the basin expect the aids from the government every year. Hence, the agricultural production has to be improved through the use of irrigation improve the food security caused by insufficient output from these rain fed systems (Worqlul et al., 2015).
The process of land suitability classification is the appraisal and grouping of specific areas of land in terms of their suitability for defined uses (FAO, 1976). This study has therefore conducted to assess the suitable land for surface irrigation using spatial parameters such as; normalized difference vegetation index (NDVI), soil type, slope, river proximity, rainfall deficit, town proximity, road proximity and land use. NDVI, use as an indicator in irrigable land suitability assessment is not common, (Gebre et al., 2021, Yonas et al., 2022) however it will give an indication to the soil fertility which is a very important parameter for crop production, in addition to the physical parameters.
Section snippets
Description of the study area
Bilate River Basin is situated in South Western Escarpment of the Main Ethiopian Rift Valley. The Basin includes the portion of Southern Nations and Nationalities Region States (SNNPRS) and small parts of the South-central Oromiya Regional States. It covers an area of 5686.86 km2.The altitude of the basin ranges from 1116 m to 3358m above sea level (Fig. 1). This indicates that the topography of the area ranges from lowland plain areas to highly rugged and mountainous elevated terrains. Due to
Results and discussion
The land suitability for surface irrigation was assessed based on the land productivity, slope, soil type, land use/land cover, land proximity to river, road and town as factors according to their weight or importance. The suitability was assessed with respect to each parameter considered separately and finally with given level of importance, or weight being overlay.
Conclusions
In this study, the suitable land for surface irrigation in Bilate River Basin was mapped based on spatial factors which affect the suitability of land for surface irrigation. Eight factors such as NDVI, Soil type, proximity to river, slope, land use, rainfall deficit, road proximity and town proximity were selected for land suitability assessment. The suitable lands were assessed based on the individual factors and weighted overlay of all the parameters using multi criterion technique. The
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgments
We would like to acknowledge the Southern Nation Nationalities People Regional State Water and Irrigation Development Bureau Irrigation Construction and Scheme Administration Agency financial support for this study.
References (31)
Soil Background Effects on Reflectance-Based CropCoefficients for Corn. (1991)
Rem. Sens. Environ.
(1993)A scalingmethod for priorities in hierarchical structures
J. Math. Psychol.
(1977)- et al.
Sustainable irrigation is necessary and achievable, but direct costs and environmental impacts can be substantial
Agric. Water Manag.
(2006) - et al.
Assessment of surface water irrigation potential in the Ethiopian highlands: The Lake Tana Basin
Catena
(2015) - et al.
Multi-criteria land suitability analysis for agriculture in hilly zone: Remote sensing and GIS approach
Comput. Electron. Agric.
(2015) - et al.
Experiences and opportunities for promoting small–scale/micro irrigationand rainwater harvesting for food security in Ethiopia
(2005) - et al.
Traditional Irrigation and Water Management Practices in highland, Ethiopia: Case Study in DangilaWoreda
Irrig. Drain.
(2013) - Benefetti, Roberto; Paolo Rossini. (1993): On the Use of NDVI Profiles as a Tool for Agricultural Statistics: The case...
- FAO, ECA and AUC. 2021. Africa regional overview of food security and nutrition, 2020: Transforming food systems for...
- Food and Agricultural Organization (FAO), 1976. A framework for land evaluation. Soils Bulletin 32. FAO and Agriculture...
Soil type is the primary determinant of the composition of the total and active bacterial communities in arable soils
Appl. Environ. Microbiol.
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