Land Suitability For Irrigation Research Articles

Evaluation of land suitability for surface irrigation under changing climate in a tropical setting of Uganda, East Africa

CONTEXTAssessment of land suitability for irrigation under changing climate holds paramount significance given the pronounced reliance on rainfed agriculture in sub-Saharan Africa. OBJECTIVETo investigate land suitability for surface irrigation under changing climate in a tropical setting of Uganda, East Africa and explore implications for irrigation development as well as food security. METHODSThe study used a GIS-based multi-criteria evaluation using the Analytical Hierarchy Process that considered seven factors: soil texture, slope, land use/land cover, soil drainage, distance to river, distance to road network and rainfall deficit. Each factor was rasterized, reclassified and standardized to a similar measuring scale, resulting in a numeric range; higher values indicating areas that are more suitable and lower values indicating areas that are less suitable for irrigation. Weighted factors were added using the weighted overlay approach in the ArcGIS environment to create the final irrigation suitability map. Suitability was further assessed under two scenarios; an increase in average temperature of 1.5 °C and 10% increase in annual rainfall for the period from 2041 to 2060 (scenario I) and an increase in average temperature of 4.3 °C and 20% increase in annual rainfall for the period from 2061 to 2080 (scenario II). RESULTS AND CONCLUSIONSFindings reveal that of the entire area of Uganda, 43.7% is currently constrained, 32.4% is moderately suitable, 23.1% is marginally suitable, only 0.9% is highly suitable, and only 0.02% is not suitable for surface irrigation. Highly suitable land is mostly found in the Lake Victoria Crescent whereas land not suitable for surface irrigation is mostly found in the Karamoja zone. Suitability of land for surface irrigation generally decreased with changing climate. Land not suitable for surface irrigation increased to 0.11% and 0.34%, and marginally suitable land increased to 28.4% and 35.8% of the total area, under scenarios I and II respectively. Whereas moderately suitable land decreased to 27.5% and 20.1%, and highly suitable land decreased to 0.29% and 0.046% of the total area, under scenarios I and II respectively. In both scenarios, suitable land for surface irrigation is highest in the South East L. Kyoga Flood Plain and lowest in the Western Mid-Altitude Farmland. The investigation underscores the dynamic nature of irrigation suitability of land, subject to various influencing factors with climate dynamics being a major factor. SIGNIFICANCEThe findings emphasize the importance of adopting adaptive strategies and incorporating climate change considerations into irrigation decision-making processes for increased food production.

Land suitability for irrigation of small reservoirs using spatial techniques in the upper regions of Ghana

AbstractRecent climatic variations have hindered the potential of irrigation in Sub‐Saharan Africa (SSA). This study presents a suitability analysis of irrigable areas for irrigation using spatial techniques. The focus of this paper was to examine regions that may be viable for irrigation for four small reservoirs constructed under the ‘One Village One Dam’ (1V1D) initiative. The thematic factors used were distance to water, soil type, soil depth, slope, pH, electrical conductivity, hydraulic conductivity, land use–land cover, organic carbon and organic matter. The land cover was classified using high‐resolution imagery from SAS Planet because of the small land size. The pairwise ranking found soil type to have an overall higher weight of approximately 15% and electrical conductivity to have the lowest weight. The highly suitable areas were found very close to the dam, and the permanently not suitable areas were located at the far end of the dam. From the area computation, it was found that the highly suitable regions in Kataa, Degri, Napaadi and Zansibulga were 10.52, 55.41, 1.01 and 3.77 ha, respectively. In conclusion, it was found that the majority of irrigable land was within the marginally to highly suitable class.

Assessment of land suitability for irrigation in West Shewa zone, Oromia, Ethiopia

The assessment of land suitability is the key to sustained agricultural output. Thus, the study aimed to assess the land suitability for irrigation development in the West Shewa zone, Oromia, Ethiopia. A GIS-based analytical hierarchy process was applied to evaluate a multi-criteria land suitability analysis. The key factors such as soil (depth, drainage, texture, pH, organic carbon, available water content, and salinity), slope, land use/cover, proximity to the river, proximity to the road, proximity to urban areas, and rainfall deficit were considered. These factors were reclassified, weighted, and then overlaid using the weighted overlay tool of ArcGIS software. The study classified the agricultural lands in the area from highly suitable to permanently unsuitable for irrigation to determine the suitability of the classes. The results showed that 10.27% (1419.87 km2) was highly suitable, 73.23% (10,128.97 km2) was moderately suitable, 16.34% (2259.95 km2) was marginally suitable, and 0.16% (22.16 km2) was not suitable. The area in all woredas was mainly moderately suitable for irrigation. However, Metarobi had the most highly suitable land, followed by Elfata with the most moderately suitable land, and Abuna Gindeberet with the most marginally suitable land. The results revealed huge potential for irrigation development in the West Shewa zone. As a result, it can serve as the basis for zonal-level planning and future irrigation development. Therefore, the study helps to improve the community’s lifestyle in the study area by increasing agricultural production.

Evaluating land suitability and water availability for surface irrigation in the Abbay basin of Ethiopia.

This study was conducted in the Abbay basin of Ethiopia to evaluate land suitability for irrigation considering both surface and groundwater sources using the analytic hierarchy process. Multiple factors which affect irrigated agriculture productivity were considered, and an 85% threshold was applied to identify irrigable land. The suitability result was validated using ground truth data from existing irrigation projects for surface water sources and depth to groundwater data for groundwater sources. The low flow potential of rivers, which is dependable for surface irrigation, was evaluated against suitable land considering the most dominant crops. The result showed that nearly 10% of the basin area (19 192 km2) and 5.3% of the basin (10 364 km2) were found suitable for surface irrigation from rivers and groundwater, respectively. South Gojam was found to be the most suitable sub-basin (approx. 3880 km2) for surface irrigation, whereas Muger was found to be the most suitable sub-basin (approx. 2105 km2) for surface irrigation from rivers and groundwater, respectively. Depth to groundwater was shallow for Muger as compared with other sub-basins. The validation result depicted more than 83% and 73% overlap for surface and groundwater sources, respectively. Land suitability and water availability assessment result in the Abbay basin shows a promising result for surface irrigation developments.

Mapping land suitability for informal, small-scale irrigation development using spatial modelling and machine learning in the Upper East Region, Ghana

Small-scale irrigation has gained momentum in recent years as one of the development priorities in Sub-Saharan Africa. However, farmer-led irrigation is often informal with little support from extension services and a paucity of data on land suitability for irrigation. To map the spatial explicit suitability for dry season small-scale irrigation, we developed a method using an ensemble of boosted regression trees, random forest, and maximum entropy machine learning models for the Upper East Region of Ghana. Both biophysical predictors including surface and groundwater availability, climate, topography and soil properties, and socio-economic predictors which represent demography and infrastructure development such as accessibility to cities and proximity to roads were considered. We assessed that 179,584 ± 49,853 ha is suitable for dry-season small-scale irrigation development when only biophysical variables are considered, and 158,470 ± 27,222 ha when socio-economic variables are included alongside the biophysical predictors, representing 77-89% of the current rainfed-croplands. Travel time to cities, accessibility to small reservoirs, exchangeable sodium percentage, surface runoff that can be potentially stored in reservoirs, population density, proximity to roads, and elevation percentile were the top predictors of small-scale irrigation suitability. These results suggested that the availability of water alone is not a sufficient indicator for area suitability for small-scale irrigation. This calls for strategic road infrastructure development and an improvement in the support to farmers for market accessibility. The suitability for small-scale irrigation should be put in the local context of market availability, demographic indicators, and infrastructure development.

Land suitability and surface water resources potential for irrigation in Becho Plain, upper Awash basin, Ethiopia*

AbstractIn this study, an assessment of the land and surface water resources potential of the Becho Plain was conducted. Land suitability for irrigated agriculture was evaluated by considering the Food and Agriculture Organization (FAO) criteria. The land suitability parameters such as soil properties, slope, land use and land cover were used to identify the suitable irrigable land. The analytical hierarchy process was employed to obtain parameter weights, and later the weighted overlay analysis in the geographic information system was employed to obtain the overall suitability of land resources for irrigation. The surface water availability and amount were evaluated by using the calibrated Soil and Water Assessment Tool (SWAT) model. The water requirement of dominant crops was estimated following the FAO procedure and compared with the available water. Nearly 70% of the land area is identified as suitable for surface irrigation, while the remaining 30% of the land area is restricted for irrigation development. The water supply and demand analysis revealed that there is sufficient water available in the Becho Plain for irrigation development. The physically possible irrigation area and diversion sites were also identified. The Becho Plain has ample land and water resources for irrigation development. However, future developments shall also consider downstream water use to implement sustainable irrigation development.

Evaluation of land suitability for irrigation using fuzzy analytic hierarchy process

Use of new techniques to evaluate irrigation areas can enhance water use efficiency in agriculture. In this study, the fuzzy analytic hierarchy Process (FAHP) was used to qualitative land suitability for sprinkler irrigation and was compared with the parametric method. Evaluation based on parametric method showed that an area of about 1597.83 hectares (31%) of the lands was (S1) and an area of about 787.3 hectares (15%) was “moderately suitable” (S2). About 2242.9 hectares (43%) were marginally (S3). Permanently inappropriate suitability included about 546.91 hectares (11%). Inappropriate in present condition suitability matched no land in the study zone. Based on the Fuzzy Analytic Hierarchical Process, there was not (S1) area in the plain. The parts with S2 suitability also included an area of about 432.96 hectares (8.3%). Moreover, areas of about 3100.98 hectares (59.9%) were marginally (S3). Some southwest and eastern parts of the plain were not currently (N1) that included an area of about 1277.68 hectares (24.6%). N2 suitability was also observed in some southern in two parts including an area of about 363.38 hectares (7%). Since about 31% of the lands were included as highly suitable areas based on the parametric method, and in contrast, there was no highly suitable areas in FAHP method, so considering the area of highly suitable shown that there was a significant difference between the two methods in terms of highly suitable land evaluation. Considering the gradual changes in soil properties, FAHP evaluation has higher accuracy than the ordinary parametric method in evaluating land suitability.

Assessment of agricultural land suitability for irrigation with reclaimed water using geospatial multi-criteria decision analysis

Water scarcity, climate variability and continuing growth in water demand have put severe pressure on high‐quality freshwater sources. This challenge exacts the necessity to explore alternative water sources for agricultural irrigation. The objective of this study was to implement the integrated geospatial Multi-Criteria Decision Analysis (MCDA) with the Analytical Hierarchy Process (AHP) to evaluate the potentiality of reclaimed water use for agricultural irrigation in California. Five evaluation criteria included in this study were agricultural land (crop type), climate conditions, water policies, irrigation status, and proximity to wastewater treatment plants (WWTPs) respectively. The suitability maps for reclaimed water use were generated for three cases in terms of accessibility to WWTPs, their discharge volume and appropriate treatment processes respectively. In addition, a composite suitability map was produced using the hybrid model considering all three cases together. Results from this study led to a better understanding of sustainable reclaimed water use for crop irrigation at a regional level. It provided supporting evidence of the applicability of the GIS-MCDA method integrated with AHP technique for a larger geographical scale with a diverse crop pattern. This study established the importance of using both knowledge-based and data-driven criteria and sub-criteria in the decision framework. The results also highlighted how the spatial distribution of suitable areas for reclaimed water reuse is closely linked to the agricultural areas.

Land Capability and Land Irrigability Classification in Garakahalli Micro- Watershed of Karnataka

Land suitability for irrigation in semi-arid regions is important for agricultural development and to overcome water scarcity. The detailed soil survey of Garakahalli micro- watershed (447 ha) of Karnataka was carried out and mapped into 85 mapping units. The soil units were evaluated for surface irrigation method. The suitability maps showed 74.06 per cent arable land, out of which 69.19 per cent of land is suitable for surface irrigation and remaining is unsuitable due to the limitation of the topography and stoniness. The detailed land resource data base in association with GIS and remote sensing was highly efficient in modeling and developing land suitability maps which can be used as a planning tool to optimize the agriculture in semi-arid regions of Karnataka.

English

Assessment of land suitability for irrigation purpose is important to utilize limited resources efficiently and for the sustainable production of crops and food security of the ever increasing people in our country especially the study area. The existing small scale irrigation system in the Guangua Badiya river basin farming area has no adequate soil and land resource information and also the irrigated area is very small. Thus irrigation land suitability assessment plays an imperative role for sustainable utilization of scarce physical land resources. This study was initiated with the objective of assessing land suitability evaluation for agriculture under irrigation of the River Guangua Badiya in Abaya District of Borena Zone, Oromiya Region, Ethiopia. Watershed delineation, assessment of soil and slope parameters were the steps followed to evaluate land suitability for irrigated agriculture. To identify land suitability for irrigation purpose, the following factors such as soil type, slope, and distance from water supply (sources) were taken into account. Soil sampling spots were selected based on free and grid survey techniques and their locations were taken using Global Positioning System (GPS). Soil samples were collected and used for suitability assessment. Soil samples used as criteria for irrigation suitability analysis were pH, texture, soil depth, EC, ESP, top and sub soil stoniness. Slope suitability map of the study area was derived from digital elevation model of the area clipped from SRTM of NASA satellite with 30 m resolution by masking layer of sub catchment. Qualitative evaluation was carried out with the help of FAO land evaluation method. Result of suitability of land evaluation ratings based on the qualitative land suitability for irrigation indicated that, 9.32% (1303 ha) are highly suitable (S1), 32.5% (4558 ha) are moderately suitable (S2), 23.82% (3335 ha) marginally suitable (S3) and 34.30 (4802 ha) are not suitable (N) for surface irrigation systems. Hence, the majority of the study areas are in a range value of highly to marginally suitable for surface irrigation purpose. Due to high slope range value 4802 ha of lands are non-suitable for irrigation purpose. Key words: Suitability, irrigation, soil properties, Guangua Badiya river.

Group decision-making in land evaluation for irrigation: a case study from Serbia

Presented in this paper is a methodology for a spatially based multi-criteria evaluation of land suitability for irrigation (IR). A group of experts use the analytic hierarchy process (AHP) and the consensus convergence model (CCM) to define weights of factors relevant in validating areas of land as suitable for IR and to develop IR suitability maps in the geographic information system (GIS) environment. Then, using those maps, a group of policy-makers apply voting methods to identify districts with priorities for installing new IR systems. The presented methodology has several benefits. Group decision can aggregate the wisdom of the different domain experts involved in the process while effectively coping with the risk inherent in any decision problem. In CCM, cooperation among experts is rewarded and non-cooperation yields the risk of being excluded from the process or having very little impact on the group decision. The presented methodology is more precise than previously published methodologies, which is more helpful for policy-makers. Finally, sometimes experts’ opinions are not comprehensive enough to formulate an objective decision, as they are based on scientific facts whereas real-life decision-making is often based on economic or political factors. Owing to that, policy-makers are included in the presented methodology.

Identification of criteria and subcriteria for assessment of land suitability for irrigation

Serbia is a country with a predominantly agriculture-based economy; however, out of the total area only 3% is irrigated. One of the strategic national development goals is to increase irrigated land especially in lowlands and alluviums of major rivers in the country. There are many criteria and subcriteria which are important for a decision on where to build new, sustainable irrigation systems. After the literature review regarding this topic, we propose a set of criteria and subcriteria for assessment of land suitability for irrigation in Vojvodina Province, Serbia. Criteria and subcriteria were identified by four experts in the subject area.

Ranking suitable sites for irrigation with reclaimed water in the Nabeul-Hammamet region (Tunisia) using GIS and AHP-multicriteria decision analysis

The present study describes an innovative methodology to rank suitable sites for irrigation with TWW using fuzzy-AHP based on GIS where the Nabeul-Hammamet aquifer catchment (Tunisia) is selected as the target area. The model is relatively simple and is extendable worldwide. Several influential parameters are identified considering simultaneously technical, social, economical and environmental aspects. They are grouped in five main criteria, namely land suitability for irrigation, resources conflicts, cost effectiveness, social acceptance and environmental impact. Each criterion is subdivided into several sub-criteria. A pair-wise matrix is used to compare these criteria and sub-criteria and to rank them according to their relative importance for site evaluation. Using GIS, geographical layers are obtained for the sub-criteria, leading to mapping and ranking the suitable sites for TWW irrigation.The results show that the total suitable area covers 11,426ha which represents 31% of the total Nabeul-Hammamet aquifer watershed. This constitutes quite a large zone that can absorb the entire volume of available treated wastewater, thereby increasing the region's agricultural production. The best sites to receive the surplus amount of TWW, produced by the treatment plants of the region, are located near these plants and inside agricultural lands. In addition, all these sites are located around the districts already irrigated by TWW, which underlines the role these districts may play in encouraging neighbouring farmers to change their attitude towards TWW and to accept it as an alternative resource for irrigation.

A "Revised" Methodology for Assessing Land Suitability for Irrigation

Advances in irrigation technology have resulted in the need to review existing methods of evaluating the suitability of land for irrigated agriculture. Previous irrigation classification systems were based largely on criteria relevant to flood methods of irrigation. This paper describes the principles and criteria of a revised method of classifying land suitability for irrigation. This revised classification scheme can provide initial assessments of the feasibility of installing either flood (gravity) or sprinkler systems.The new methodology focuses on interpreting the suitability of land for irrigation utilizing soil and landscape data made available through regular soil survey programs. Guidelines are provided to facilitate the ranking of soil and landscape attributes in terms of their degree of limitation for irrigation. Land with no significant limitation(s) for soils and/or landscapes receives an excellent rating; land with slight limitation(s) for soils and/or landscapes is rated as good; land with ...