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Increase in irrigated area, driven by demand for more food production, in the semi-arid regions of Asia and Africa is putting pressure on the already strained available water resources. To cope and manage this situation, monitoring spatial and temporal dynamics of the irrigated area land use at basin level is needed to ensure proper allocation of water. Publicly available satellite data at high spatial resolution and advances in remote sensing techniques offer a viable opportunity. In this study, we developed a new approach using time series of Landsat 8 (L8) data and Random Forest (RF) machine learning algorithm by introducing a hierarchical post-processing scheme to extract key Land Use Land Cover (LULC) types. We implemented this approach for Mashhad basin in Iran to develop a LULC map at 15 m spatial resolution with nine classes for the crop year 2015/2016. In addition, five irrigated land use types were extracted for three crop years-2013/2014, 2014/2015, and 2015/2016-using the RF models. The total irrigated area was estimated at 1796.16 kmc, 1581.7 km 2 and 1578.26 km 2 for the cropping years 2013/2014, 2014/2015 and 2015/2016, respectively. The overall accuracy of the final LULC map was 87.2% with a kappa coefficient of 0.85. The methodology was implemented using open data and open source libraries. The ability of the RF models to extract key LULC types at basin level shows the usability of such approaches for operational near real time monitoring.

The area to be cropped in irrigation districts needs to be planned according to the available water resources to avoid agricultural production loss. However, the period of record of local hydro-meteorological data may be short, leading to an incomplete understanding of climate variability and consequent uncertainty in estimating surface water availability for irrigation area planning. In this study we assess the benefit of using global precipitation datasets to improve surface water availability estimates. A reference area that can be irrigated is established using a complete record of 30 years of observed river discharge data. Areas are then determined using simulated river discharges from six local hydrological models forced with in situ and global precipitation datasets (CHIRPS and MSWEP), each calibrated independently with a sample of 5 years extracted from the full 30-year record. The utility of establishing the irrigated area based on simulated river discharge simulations is compared against the reference area through a pooled relative utility value (PRUV). Results show that for all river discharge simulations the benefit of choosing the irrigated area based on the 30 years of simulated data is higher compared to using only 5 years of observed discharge data, as the statistical spread of PRUV using 30 years is smaller. Hence, it is more beneficial to calibrate a hydrological model using 5 years of observed river discharge and then to extend it with global precipitation data of 30 years as this weighs up against the model uncertainty of the model calibration.

Remote sensing techniques have been shown, in several studies, to be an extremely effective tool for assessing the performance of irrigated areas at various scales and diverse climatic regions across the world. Open access, ready-made, global ET products were utilized in this first-ever-countrywide irrigation performance assessment study. The study aimed at identifying 'bright spots', the highest performing sugarcane growers, and 'hot spots', or low performing sugarcane growers. Four remote sensing-derived irrigation performance indicators were applied to over 302 sugarcane growers; equity, adequacy, reliability and crop water productivity. The growers were segmented according to: (i) land holding size or grower scale (ii) management regime, (iii) location of the irrigation schemes and (iv) irrigation method. Five growing seasons, from June 2005 to October 2009, were investigated. The results show while the equity of water distribution is high across all management regimes and locations, adequacy and reliability of water needs improvement in several locations. Given the fact that, in general, water supply was not constrained during the study period, the observed issues with adequacy and reliability of irrigation in some of the schemes were mostly due to poor scheme and farm level water management practices. Sugarcane crop water productivity showed the highest variation among all the indicators, with Estate managed schemes having the highest CWP at 1.57 kg/m3 and the individual growers recording the lowest CWP at 1.14 kg/m3, nearly 30% less. Similarly center pivot systems showed to have the highest CWP at 1.63 kg/m3, which was 30% higher than the CWP in furrow systems. This study showcases the applicability of publicly available global remote sensing products for assessing performance of the irrigated crops at the local level in several aspects.

Irrigated agriculture, particularly small-scale irrigation (SSI), is a mainstay for sustainable livelihoods in the developing world. In Ethiopia, SSI sustainability is threatened mainly due to excessive sedimentation. Stakeholders' perceptions of the causes of sedimentation and how they sustain SSI under excessive sedimentation conditions were investigated in two SSI schemes in Ethiopia. A participatory rapid diagnosis and action planning was implemented, consisting of a literature review, participatory rural appraisal, and semi-structured interviews. Results show that farmers slightly differed in perception of excessive sedimentation drivers. Farmers reported design problems as the main cause of excessive sedimentation (64%), followed by poor operation and maintenance (O and M) practices (21%) and external factors (15%). In contrast, 62% of the interviewed engineers indicated erosion and irrigation technologies as the main causes of excessive sedimentation, while few reported poor design (13%). In addition to an intensive desilting campaign, farmers delayed the start of the irrigation season to avoid the intake of highly sedimented water. Local social capital and knowledge appeared to be more important than formal knowledge and blue-print institutions for dealing with sedimentation problems. Well-organized structure and extra time devoted by famers were vital for SSI sustainability. Integration of the farmers' knowledge with that of the engineers could yield more effective ways to deal with sedimentation problems.

Sediments cause serious problems in irrigation systems, adversely affecting canal performance, driving up maintenance costs and, in extreme cases, threatening system sustainability. Multiple studies were done on the deposition of non-cohesive sediment and implications for canal design, the use of canal operation in handling sedimentation problems is relatively under-studied, particularly for cohesive sediments. In this manuscript, several scenarios regarding weirs and gate operation were tested, using the Delft3D model, applied to a case study from the Gezira scheme in Sudan. Findings show that weirs play a modest role in sedimentation patterns, where their location influences their effectiveness. On the contrary, gate operation plays a significant role in sedimentation patterns. Reduced gate openings may cause canal blockage while intermittently fully opening and closing of gates can reduce sediment deposition in the canal by 54% even under conditions of heavy sediment load. Proper location of weirs and proper adjusting of the branch canal's gate can substantially reduce sedimentation problems while ensuring sufficient water delivery to crops. The use of 2D/3D models provides useful insights into spatial and temporal patterns of deposition and erosion but has challenges related to running time imposing a rather coarse modelling resolution to keep running times acceptable.

Drip irrigation is represented in literature and agricultural policies as a modern and water saving technology. Because this technology is often associated with ‘modern’ agriculture and development, it seems out-of-place in ‘traditional’ farmer managed irrigation systems (FMIS). Thinking along the binary modernity-tradition leaves little room for the possibility that drip irrigation and FMIS could come together in a meaningful way as they place FMIS and drip irrigation in two mutually exclusive representational categories. Yet, the water users from the Khrichfa Canal, part of the Ain Bittit Irrigation System, a ‘traditional’ FMIS in Northern Morocco, opt for ‘modern’ drip irrigation as technology of their choice. To explain this apparent contradiction this PhD thesis develops an approach to rethinking the performance of drip irrigation in the context of farmer managed irrigation systems. The question “how does drip irrigation perform?” guides this research. In irrigation engineering literature the performance of drip irrigation is centred around the notion of water use efficiency – the prime task that drip irrigation is supposed to fulfil. However, to understand drip irrigation in FMIS, a more processual and less prescriptive approach to performance is explored. Drawing on actor-network approaches, the thesis understands performance as “the art of ordering the relations and interactions between people and objects, a process of ordering which emerges from practice and which results in contingent, surprising outcomes.” This study starts by ‘unpacking’ the efficiency of drip irrigation by exploring what efficiency means, how the strong link between drip irrigation and efficiency was constructed, and what this association of drip irrigation as an efficient technology does. Because of its renowned efficiency, drip irrigation introduction is stimulated in many countries. Yet, efficiency is not an uncontested term. From the academic debate on efficiency complexity, it is c

Development agencies enthusiastically promote micro-drip irrigation as an affordable water and labor-saving device, yet most farmers stop using it as soon as development projects end. This article analyzes why farmers engage in projects promoting drip irrigation kits, even though they appear not to be interested in their water and labor-saving attributes. We combine practice-based theories of innovation with insights from the anthropology of development to explain that in development project arenas, micro-drip kits have different meanings for farmers than for the actors promoting the technology. Accepting the technology is just one element of more encompassing strategic efforts by farmers to obtain benefits from development projects. Hence, in the arena of the development project and for farmers, micro-drip kits are defined by the side benefits that accompany their introduction, such as motorized pumps, free inputs, the promise of credit, or the prospect of acquiring social prestige and forging new alliances.

Title: Low cost drip irrigation in Burkina Faso: Unravelling Actors, Networks and Practices In Burkina Faso, there is a lot of enthusiasm about Low Cost Drip Irrigation (LCDI) as a tool to irrigate vegetables, and thus improve food security, solve water scarcity and reduce poverty. Already for more than ten years, development cooperation donors, policy makers, and kit designers have invested in the technology, funded its dissemination, and encouraged farmers to adopt it. Yet, there are only very few farmers who are using the technology in their fields. This study shows that this is because the funds for paying the technology mostly do not come from them, but from external donors. For LCDI promoters and disseminators, LCDI is also importantly a tool to survive or make profits. For this, they need to continuously re-assert the success of the technology through reports and stories. Farmers agree to play this game, as they hope and do receive other benefits by associating themselves with LCDI projects.

With a growing and increasingly wealthy and urban population, it is likely that the role of agricultural water management in ensuring food security will become more important. Pressure on water resources is high. Adverse environmental impacts as a result of sometimes poor management of irrigation and drainage are well documented, calling into question the sustainability of some of the current water management practices. Water, food, energy and climate are intrinsically connected. Greater pressure on water resources and, hence, stronger interconnectivity between sectors sharing these resources, call for new, integrated approaches to agricultural water management. This paper explores the links between water, food, energy and climate. It then explores the role of irrigation and drainage in food production and in providing other ecosystem services that are essential for the sustainable use of natural resources. The paper argues that looking at water for food production in isolation would miss important developments outside the water sector that determine the sustainability of agricultural water management. Integrated approaches to food production are not only necessary to ensure sustainability. They also lead to higher benefits per unit of water. For example, integrating food production with other ecosystem services provided by irrigation and drainage not only contributes to sustainability, it also leads to much higher economic value of benefits. This implies breaking disciplinary boundaries and encouraging greater cooperation from planning to implementation.