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Surface irrigation is associated with low irrigation efficiencies and exerts a lot of pressure on water resources. Despite this, the irrigation method remains dominant in Malawi and other sub-Saharan Africa countries. A need exists to improve surface irrigation efficiencies in the wake of water scarcity. Applications of surface irrigation simulation, evaluation and design (SIRMOD) software in improving surface irrigation performance have been reported worldwide. However, no documentation exists on SIRMOD application in Malawi. A study was therefore conducted to investigate how furrow irrigation system performance could be improved at Kasinthula Cane Growers Scheme in Malawi using SIRMOD software. Field data collected from the scheme were used to calibrate the model before simulating water advance and recession times. Statistical comparisons of the simulated advance and recession times with corresponding observed field data showed that the model closely simulated field conditions; hence, it was deemed suitable for the scheme. Results from SIRMOD optimization procedure indicated that application efficiencies could be improved by 32–63% through reductions in furrow lengths, water inflow sizes and inflow cutoff times. The study established the need for Malawi and other developing countries to develop policies on optimization of irrigation performance using computer models such as SIRMOD. [ABSTRACT FROM AUTHOR]

Ensuring food security has become a challenge in Sub-Saharan Africa (SSA) due to combined effects of climate change, high population growth, and relying on rainfed farming. Governments are establishing shared irrigation infrastructure for smallholder farmers as part of the solutions for food security. However, the irrigated farms often failed to achieve the expected crop yield. This is partly due to lack of water management system in the irrigation infrastructure. In this work, IoT-based irrigation management system is proposed after investigating problems of irrigated farmlands in three SSA countries, Ethiopia, Kenya, and South Africa as case studies. Resource-efficient IoT architecture is developed that monitors soil, microclimate and water parameters and performs appropriate irrigation management. Indigenous farming and expert knowledge, regional weather information, crop and soil specific characteristics are also provided to the system for informed-decision making and efficient operation of the irrigation management system. In SSA, broadband connectivity and cloud services are either unavailable or expensive. To tackle these limitations, data processing, network management, irrigation decisions and communication to the farmers are carried out locally, without the involvement of any back-end servers. Furthermore, the use of green energy sources and resource-aware intelligent data analysis algorithm is studied. It is expected that an intelligent data analysis will help to discover new knowledge that support further development of agricultural expertise. The proposed IoT-based irrigation management system is expected to contribute towards long term and sustainable high crop yield with minimum resource consumption and impact to the biodiversity around the case farmlands. [ABSTRACT FROM AUTHOR]

Increasing agricultural productivity in Africa will have important impacts not only on the agricultural sector but also can be a catalyst for industrialization through agro-processing. Irrigation, therefore, has a crucial role in enhancing food security and reducing hunger in the region. Numerous countries in Africa consider water and irrigation management as a key factor in improving their food security and ensuring access to drinking-water for their populations. Fortunately, there is evidence from a number of places on the continent where the adoption of efficient irrigation systems has led to higher productivity among smallholder farmers. While the appropriate interventions for the diverse agro-ecological zones of sub-Saharan Africa are known, adoption among smallholder farmers still remains a challenge. Digital technology opens the vast untapped potential for farmers, investors, and entrepreneurs to improve the efficiency of food production and consumption in Africa. From precision farming to an efficient food supply chain, technology could bring major economic, social, and environmental benefits. Increasing investment and involvement of the private sector is crucial for the up-scaling of irrigation technologies. Indeed, the sheer optimism across the startup ecosystem is that extreme hunger can be cured in Africa, in this generation, by significantly transforming the industry that employs most of its citizens. This paper draws on lessons from past trends in the irrigation industry and emphasizes on novel directions to ensure that farmers, as well as other stakeholders reap the benefits associated with improved technologies. [ABSTRACT FROM AUTHOR]

This article explores how irrigation management transfer policies were implemented in Mali, Mozambique, Malawi and Zimbabwe. In Mali and Mozambique, where the irrigation bureaucracy controlled one large irrigation system, state agencies retained control over irrigation management despite reduced state funding. In Malawi and Zimbabwe, where the state irrigation systems and the irrigation bureaucracy were smaller, users have taken over irrigation management, but are having trouble sustaining irrigated agriculture. We show how irrigation management transfer policies were shaped by the interplay between international donors, macro-economic dynamics, national politics and the interactions with (and the nature of) irrigation infrastructure, bureaucracies and organized users. [ABSTRACT FROM AUTHOR]

The present study evaluates the predictive accuracy of the feed forward backpropagation artificial neural network (BP) in evapotranspiration forecasting from temperature data basis in Dédougou region located in western Burkina Faso, sub-Saharan Africa. BP accuracy is compared to the conventional Blaney-Criddle (BCR) and Reference Model developed for Burkina Faso (RMBF) by referring to the FAO56 Penman-Monteith (PM) as the standard method. Statistically, the models' accuracies were evaluated with the goodness-of-fit measures of root mean square error, mean absolute error and coefficient of determination between their estimated and PM observed values. From the statistical results, BP shows similar contour trends to PM, and performs better than the conventional methods in reference evapotranspiration (ET_ref) forecasting in the region. In poor data situation, BP based only on temperature data is much more preferred than the other alternative methods for ET_ref forecasting. Furthermore, it is noted that the BP network computing technique accuracy improves significantly with the addition of wind velocity into the network input set. Therefore, in the region, wind velocity is recommended to be incorporated into the BP model for high accuracy management purpose of irrigation water, which relies on accurate values of ET_ref. [ABSTRACT FROM AUTHOR]

Food security is a concern in many parts of the tropics, but it is an acute problem in a band of countries bordering the Sahara desert on the south-Sub-Saharan Africa. Crop productivity and production, stability, and resilience to adverse events seem to be diminishing with time. Low productivity is related to both adverse soil conditions and insufficient rainfall amounts and distribution. Portions of the region receive substantial amounts of rainfall, yet much is lost during intense storms. A rainfall capturing technology "Aménagement en courbes de niveau" (ACN), a variant of closely spaced, narrow-base terraces, has been developed in Mali and has proven beneficial in several West African countries. A field where ACN had been installed was instrumented to quantify the effects of ACN on soil/water availability. Capacitance probes were installed to 160 cm so that soil moisture measurements could easily be taken two to three times a week during 2 years - 2003 and 2004. Soil moisture profiles indicated that substantially more water was retained in soils where the ACN technology was installed than where it was not present. The ACN technology led to increased soil moisture during the first month of rains. However, the differences in soil moisture were greatest at the end of the rainy season when soil moisture of the subsoil was much greater where the ACN technology had been implemented. Moisture contents were greater in the soil profile 80-160 cm with values ranging 0.18-.21 cm3 cm-3 compared to 0.15 in the No-ACN plots. [ABSTRACT FROM AUTHOR]

This review identifies the potentials and constraints of using (partially) treated or blended wastewater for irrigation in order to assess the potentials in the context of cities in sub-Saharan Africa, specifically Maputo, the capital of Mozambique. Less than 5% of the wastewater produced in the region is being treated. Nonetheless, untreated, partially treated, and/or blended wastewater is extensively being used for agricultural purposes. Despite the last updated WHO 2006 guidelines for 'wastewater use in agriculture', authorities only consider the different water quality parameters at the point of use. Other aspects such as irrigation type, crop management and post harvesting practices, which clearly influence the contaminant log reduction, are simply ignored. Those parameters, however, are considered alternatives to a classic contaminant log reduction, which may be very beneficial for developing countries. In a more holistic approach, trade-off is favoured between the required water quality for irrigation, use of affordable treatment technologies, and adequate post-harvest strategies to reduce the current health risks to acceptable levels. Such a trade-off makes use of multiple barrier approach, whereby wastewater treatment and critical point barriers throughout the supply chain are combined. Thus, there is a long way ahead to achieve proper water reclamation for productive use; the current paradigm has to change. Current restrictive guidelines are unrealistic given current practices, and approaches more appropriate to the location's situation still need to be developed. A multiple barrier approach in combination with master planning is recommended to consider wastewater treatment and critical point barriers throughout the supply chain. • There is potential for water reclamation in African countries. • Restrictive irrigation might be unrealistic in developing countries. • Urgent need of cost-effective technologies to treat wastewater to desirable levels. • More appropriate approaches to the location's situation still need to be developed. • Multiple barrier approach combining treatment and critical barriers at supply chain. [ABSTRACT FROM AUTHOR]

Traditional methods based on field campaigns are generally used to assess the performance of irrigation schemes in Burkina Faso, resulting in labor-intensive, time-consuming, and costly processes. Despite their extensive application for such performance assessment, remote sensing (RS)-based approaches remain very much underutilized in Burkina Faso. Using multi-temporal Landsat images within the Python module for the Surface Energy Balance Algorithm for Land model, we investigated the spatiotemporal performance patterns of the Kou Valley irrigation scheme (KVIS) during two consecutive cropping seasons. Four performance indicators (depleted fraction, relative evapotranspiration, uniformity of water consumption, and crop water productivity) for rice, maize, and sweet potato were calculated and compared against standard values. Overall, the performance of the KVIS varied depending on year, crop, and the crop's geographical position in the irrigation scheme. A gradient of spatially varied relative evapotranspiration was observed across the scheme, with the uniformity of water consumption being fair to good. Although rice was the most cultivated, a shift to more sweet potato farming could be adopted to benefit more from irrigation, given the relatively good performance achieved by this crop. Our findings ascertain the potential of such RS-based cost-effective methodologies to serve as basis for improved irrigation water management in decision support tools. [ABSTRACT FROM AUTHOR]