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International audience; Promoting innovation to improve both productivity and sustainability of irrigated farming systems is crucial for the first question addressed within the Sustainable Development Goals process led by the United Nations. This is a complex task that requires methods and processes which include a diversity of knowledge. For this reason, participatory approaches have been increasingly encouraged. A broad range of methods have been developed in the literature. However, debates on the effectiveness of the results, including questions on how different stakeholders influence results and how the context influences platform processes, remain theoretical. In this article, the authors evaluate the results of a participatory diagnosis aiming to identify the constraints and possible innovations to improve agricultural production in the Brahmi irrigation scheme in Tunisia. The process was implemented with individual interviews and focus groups operationalized through two types of platforms, 'Community of Practice (CoP)' and 'Learning and Practice Alliance (LPA)'. We highlighted that both CoP and LPA offer fruitful platforms for the interaction of all stakeholders. However, the results could be biased by the context and the expectations and strategies of powerful participants. Individual interviews are complementary to focus group results, especially in situations where open or latent conflicts exist.

Rural livelihood diversification has become a central policy in rural development and poverty alleviation. Farmworkers in irrigation schemes are a typical poor sub-group that has received little attention in research regarding their livelihood status and the contribution of diversification. This paper provides evidence derived from a study that was carried out to examine whether farmworkers in the study area diversify their livelihoods and identify their choices of livelihood-diversification strategies and the determinants thereof. Data were collected from 191 randomly selected farmworkers and analyzed using the binary probit model and the multinomial logistic model. Variables considered in the binary probit model—gender, number of dependents, employment type, farming experience, land leasing, and market access—influenced livelihood diversification among irrigation farmworkers in a statistically significant way. The multinomial logistic model analysis considered age, marital status, household dependents, leasing land from employer, farming experience, agricultural training, and access to markets as the statistically significant factors that influence the choice of livelihood-diversification strategies in the study area. The study concluded that rural development policies should consider leasing land to irrigation farmworkers that is adequate to reduce poverty, achieve food security, and sustain the livelihoods of farmworkers in the study area, as it boosts the generation of income.

This study was conducted to highlight status and distribution of potentially toxic elements (PTEs) in Usangu agroecosystem-Tanzania. The study involved 198 soil samples from 10 irrigation schemes including three land use. The concentrations of selected PTEs (Cd, Cr, Cu, Pb, Zn, As, Hg, Co, Nie etc.) were determined to estimate status, distribution, and contamination hierarchy. The total and bioavailable PTEs were determined by aqua regia digestion and Mehlich 3 methods, respectively. We observed variable total PTEs concentration (in mg/kg) among land use and irrigation schemes such as Cr (15), Co (2.9), Fe (7371), Mn (263), and Zn (18.2). Also, concentration of other PTEs (in µg/kg) were As (1382), Cd (22), Cu (3342), Hg (3.3), Ni (4107), and Pb (5661). It was observed that 99.5, 87, 66 and 12% of the studied soils had total Fe, As, Se and Hg concentration above allowable threshold in agricultural soils, respectively. The bioavailable PTEs fraction were lower than total values from different land use and irrigation schemes, higher values of bioavailable PTEs were associated with agricultural intensifications. The status of PTEs in Usangu agroecosystem observed to be at level potentially to cause damaging effect to soil invertebrates, plants, animals and human if remain unregulated. This study highlights baseline information and evidence for site-specific environmental management planning and a scientific basis required to establish PTEs management in agricultural soils to ensure health food and environmental safety.

Kaman, Harun/0000-0001-9308-3690 WOS: 000355604900014 This study examined evaluation of the physical and financial performance criteria of 24 irrigation schemes in Antalya Valley located in the Mediterranean Region in Turkey between 2007 and 2012. In this study, physical and financial performances included irrigation ratio, sustainability of irrigated area and relative water supply ratios, and water fee collection efficiency and service area per personnel, were examined. The results of this study indicated that irrigation ratios of schemes are between 12 and 84%. The rate of sustainability in irrigated land of schemes was close to 1.0 except Caybogazi, Deniztepesi and Dosemealti schemes. The relative water supply of most of the schemes such as Aksu-North, Aksu Middle, Alara Left Bank, Caybogazi, Gazipasa, Karaman Duraliler, Koprucay Right Bank, Kumluca Birlik and Manavgat Right Bank is higher than 2.5 because they consumed more water. The water fee collection efficiency was between 28 and 100% while service area per personnel between 10.7 and 1834.8 ha/person in all schemes from studied area. However, irrigation ratios of some schemes are needed to be recovered. The water fee collection efficiency and service area per personnel in most of schemes are satisfactory.

International audience; The irrigation performance criteria of equity and adequacy are of primary concern for irrigation managers. The input data required at various scales to assess irrigation performance, often not available, need costly intensive field campaigns. Remote sensing techniques, used to directly estimate crop evapotranspiration (ETc), became recently an attractive option to assess irrigation performance from individual fields to irrigation scheme or river basin scale. In this study, ETc maps were obtained by combining the FAO-56 dual approach with relationships between crop biophysical variables and NDVI (Normalized Difference Vegetation Index), using high spatial resolution time series of SPOT and Landsat images. This approach was applied for 2002/2003 growing season in Haouz plain, Morocco. Remote sensing-based indicators, reflecting equity and adequacy of the irrigation water delivery were estimated. Adequacy was determined according to Relative Irrigation supply (RIS), Depleted Fraction (DF) and Relative Evapotranspiration (RET) and equity according to the coefficient of variation of ETc. The analysis of these indicators exhibits a great variability among fields. Variability in irrigation performance at all levels, associated factors and possible improvements are discussed. This study demonstrates how remote sensing-based estimates of water consumption provide better estimates of irrigation performance at different scales than the traditional field survey methods.

Long-term irrigation activities in arid and semi-arid areas causes soil salinity problem. Thus, knowing soil salinity status is a prerequisite for designing appropriate irrigation management strategies. This study was therefore conducted to predict top-soil salinity of Timuga irrigation scheme and to map its spatial distribution using geostatistical techniques. An area of 33.5 km2 was delineated, and regularly spaced grid (cell size: 500 m) of sampling points were generated using fishnet of the ArcGIS 10.2. A total of 106 composite soil samples were collected from each sampling points at a depth of 20 cm and geo-referenced using global positioning system. Soil samples were analyzed for pH, electrical conductivity (ECe), cation exchange capacity, and exchangeable bases (Ca++, Mg++, K+, and Na+) following the standard laboratory procedure. Both descriptive statistics and ordinary kriging interpolation techniques were used to analyze the data. The result showed that electrical conductivity ranged from 0.125 to 12.89 mScm−1 and the exchangeable sodium percentage ranged from 0.094% to 27.514%. This indicated that soils of the irrigation scheme are characterized by saline and sodic soils with different degree of spatial variability. The total area of 75.3% and 24.7% has classified as low and medium salinity hazards, respectively. However, 3.11%, 76%, and 20.89% of the total area have classified as high, medium, and low sodicity levels, respectively. Therefore, it was concluded that soil salinity hazard is existed and is building up of gradually in parallel with irrigation expansion. Hence, prevention and recovery measures are needed considering a variety of options such as leaching, fertilization, and planting salinity-resistant crop varieties to sustain irrigation productivity.

The status and characteristics of the 302 smallholder irrigation schemes found in South Africa are discussed and knowledge on South African smallholder irrigation schemes generated by the Water Research Commission (WRC) over a period of nearly 20 years is reviewed. Themes covered include planning, design and technology; plot-holders and their livelihoods; institutions and organisations; support services; agronomic practices; and revitalisation. The availability of guidelines on most of these aspects is highlighted. Gaps in the knowledge of social, human and economic aspects of smallholder irrigation schemes are pointed out.Keywords: smallholder, irrigation scheme, plot size, technology, livelihoods, farmer support, institutions, organisations, revitalisation, management

Chapter 4 Turkey is classified as a relatively water-abundant country with an average of 3,900 cubic meters per person per year availability of potential water resources. The potential cannot be fully developed, and the availability is not evenly distributed in time and space. Usable potential is 1,830 cubic meters per person per year, and 30 percent of this potential was consumed in 1993. The share of the agricultural sector in total consumption is around 75 percent. Lack of well-defined property rights and centralized supply management hinder the efficient use of already developed water resources.

"In recent years, large-scale agricultural investment projects have increased in sub-Saharan Africa as a result of the growing appetites of local and international investors for land resources. Research has so far mainly focused on land issues, but the water implications of these land deals are starting to surface. Taking the Office du Niger (ON), in Mali, as a case study, we show that while around 100,000 ha is currently being cultivated, mostly by smallholders, a total of 600,000 ha of land has been allocated in the past ten years to investors in large-scale farming. This process has largely bypassed the official procedure established by the ON at regional level. The allocation of new lands has shifted to the national level, with an attempt to recentralize the management of land deals and associated benefits at the highest level, despite contrary efforts by foreign donors to strengthen the ON. This article describes the complex allocation process based on 'behind-closed-doors' negotiations. It then analyses the implications of the land deals on water issues by focusing on the strategies of actors to limit the risk of future water shortages, the current and expected difficulties in water management and allocation, and the emerging spatial and social redistribution of benefits and risk that signals a process of water grabbing."