Irrigation Performance Assessment Research Articles

Performance assessment and indicators for agricultural water management—A review

AbstractThe complexity of irrigation systems and the need to adapt them to uncertainties requires developing approaches to synthesize their performances. This paper reviews performance assessment and indicators for agricultural water systems. It is aimed at finding various methods and indices used for irrigation performance assessment and standard classes for their characterization. The global application of the metrics was also documented. Adopting a systematic review approach, peer‐reviewed journal articles published in the English language in the last two decades (1 March 2001 to 31 December 2020) were surveyed. Case studies were presented demonstrating the application of the indicators. The study revealed a lack of standardization and the use of a wide range of indicators among others, and recommended representing certain indicators as single. However, this review considered one indicator as the best. Suggestions for further studies were made.

Assessment of Irrigation Performance: A Case Study Şanlıurfa/Bozova Yaylak Plain Pumped Irrigation Scheme

Sulama projelerinin etkin ve verimli işletme, bakım ve yönetimi tarımsal üretim üzerinde etkilidir. Bu nedenle son yıllarda sulama projelerinin performanslarının sürekli izleme ve değerlendirmesi konusu önem kazanmıştır. Bu çalışmada, sulama performansını değerlendirmek amacı ile Devlet Su İşleri tarafından inşa edilen Atatürk Barajı Sulama Birliği tarafından işletilen Şanlıurfa/Bozova Yaylak Ovası Pompaj Sulama Projesi materyal olarak alınmıştır. Çalışma kapsamında; 2018-2022 yılları verileri kullanılarak sulamada enerji kullanım etkinliği, finansal yeterlilik ve sulama suyu kullanım etkinliği başlıkları altında toplam 14 farklı performans göstergesi kullanılmıştır. Ortalama spesifik enerji değeri 0.18 kWh m-3, sulanan alanda birim alan için tüketilen enerji 2270 kWh ha-1, sulanan alanda birim alan için harcanan enerji maliyeti 2602 TL ha-1, şebekeye alınan suyun birim enerji maliyeti 0.19 TL m-3, tüketilen enerji maliyetinin gerçekleşen gidere oranı %0.79 olarak belirlenmiştir. Finansal yeterlilik göstergeleri ortalama sonuçlarına göre; gerçekleşen bakım-onarım giderinin gerçekleşen gelire oranı %33, masrafları karşılama oranı %80, sulanan alanda birim sulama alanına harcanan bakım-onarım masrafı 707 TL ha-1, ve gelir toplama performansı ise %63 olarak hesaplanmıştır. Sulama suyu kullanım etkinliği göstergelerine göre ise; sulama alanında birim alana iletilen yıllık sulama suyu miktarı ortalama 6988 m3 ha-1 ve sulanan alanda birim alana iletilen yıllık sulama suyu miktarı ortalama 12810 m3 ha-1 olarak hesaplanmıştır. Yapılan değerlendirmeler neticesinde; tarımsal enerji tarifesinde artan yüksek maliyetler nedeni ile suyun ölçülü verilmesi ve yenilenebilir enerji kaynaklarının kullanılması gerekmektedir.

Assessment of Irrigation Performance by Using Remote Sensing Techniques in Naryanpur Command Area, India

Assessment of irrigation performance for any irrigation scheme becomes necessary to know about effectiveness in terms of its operational management and socio-economic impacts. This study will focus on the performance assessment parameters computed using meteorological, optical datasets, and ground measurements for the Narayanpur Command Area. Net crop area is calculated for both Kharif and Rabi seasons using Optical Datasets for 2018-19. Atmospherically calibrated Sentinel 2 MSI images were used to identify major crop types by using supervised algorithms. Actual and Potential Evapotranspiration was also computed from meteorological datasets for the same duration. The surface Energy Balance algorithm was used for calculating potential Evapotranspiration. Crop water stress index and crop coefficient were computed and multiplied with potential evapotranspiration for getting actual evapotranspiration. It was observed that the actual evapotranspiration for both Kharif and Rabi crops varied from 700 mm to 1550 mm. The temporal scale for each growth stage was evaluated to analyse operational performance based on the growth phase of major crops grown in the Narayanpur command area. For performance assessment, depleted fraction, relative evapotranspiration, and relative water supply index were calculated. Most of the growth stages' depleted fractions varied from 0.6 to 0.9 and relative evapotranspiration varied from 0.7 to 0.92. The relative water supply for Kharif was estimated as 1.05 and for Rabi, it was 0.69.

A framework for irrigation performance assessment using WaPOR data: the case of a sugarcane estate in Mozambique

Abstract. The growing competition for finite land and water resources and the need to feed an ever-growing population require new techniques to monitor the performance of irrigation schemes and improve land and water productivity. Datasets from FAO's portal to monitor Water Productivity through Open access Remotely sensed derived data (WaPOR) are increasingly applied as a cost-effective means to support irrigation performance assessment and identify possible pathways for improvement. This study presents a framework that applies WaPOR data to assess irrigation performance indicators, including uniformity, equity, adequacy, and land and water productivity differentiated by irrigation method (furrow, sprinkler, and centre pivot) at the Xinavane sugarcane estate, Mozambique. The WaPOR data on water, land, and climate are in near-real time and spatially distributed, with the finest spatial resolution in the area of 100 m. The WaPOR data were first validated agronomically by examining the biomass response to water, and then the data were used to systematically analyse seasonal indicators for the period 2015 to 2018 on ∼8000 ha. The WaPOR-based yield estimates were found to be comparable to the estate-measured yields with ±20 % difference, a root mean square error of 19±2.5 t ha−1 and a mean absolute error of 15±1.6 t ha−1. A climate normalization factor that enables the spatial and temporal comparison of performance indicators are applied. The assessment highlights that in Xinavane no single irrigation method performs the best across all performance indicators. Centre pivot compared to sprinkler and furrow irrigation shows higher adequacy, equity, and land productivity but lower water productivity. The three irrigation methods have excellent uniformity (∼94 %) in the four seasons and acceptable adequacy for most periods of the season except in 2016, when a drought was observed. While this study is done for sugarcane in one irrigation scheme, the approach can be broadened to compare other crops across fields or irrigation schemes across Africa with diverse management units in the different agroclimatic zones within FAO WaPOR coverage. We conclude that the framework is useful for assessing irrigation performance using the WaPOR dataset.

Spatial variability assessment of irrigation performance in the Lower Usuthu Smallholder Irrigation Project (LUSIP) in Eswatini

Spatial variability assessment of irrigation performance in the Lower Usuthu Smallholder Irrigation Project (LUSIP) in Eswatini

Performance of Groundwater Irrigation System as Perceived by Farmers in West Bengal

In spite of being the most fundamental stakeholder, farmers often receive least attention for assessment of irrigation performance. Present study assessed the performance of groundwater irrigation systems being managed by water user associations (WUAs) in Burdwan (East) district of West Bengal from the perspectives of farmers during the year 2019. A random sample of 120 famers under four groundwater irrigation systems perceived that most of the parameters of irrigation performance in term of irrigation service utility at a higher level with mean perception score >4.0 except for the certainty of water delivery (2.67) leading to overall mean perception score 4.12 in kharif season. Farmers perceived similarly in rabi season with overall mean perception score 4.15; however, the overall perception of farmers regarding irrigation in summer season was relatively low (3.78). Overall irrigation performances under the jurisdiction of WUAs was perceived very good by all the farmers for all three seasons with index values more than 93 per cent. The farmers’ participation in irrigation management has helped in better water management that advocates for promoting participatory irrigation management through WUAs in all the minor irrigation systems to overcome low irrigation efficiency and other management constraints being faced in irrigated areas.

Orchard Level Assessment of Irrigation Performance and Water Productivity of an Irrigation Community in Eastern Spain

Over the last three decades, a great investment effort has been made in the modernization of irrigation in the Valencian Community (Spain). The initial change from distribution networks to pressurized ones and the shift towards drip irrigation systems was followed by improvements in irrigation scheduling, based on agrometeorological data, soil water content sensors, and remote sensing. These improvements are considered adequate for increasing irrigation water use efficiency, but it is difficult to find systematic measurements to assess its impacts on irrigation adequacy along with irrigation productivity in fruit orchards. This work presents the results of a four year assessment of irrigation water and energy use efficiency along with water productivity of a recently established irrigation community in the province of Valencia (Spain). The study was carried out at the orchard level and focused on two fruit crops: persimmon and peach trees. Six irrigation performance indicators, relative water supply (RWS), relative irrigation supply (RIS), yield performance (Yp), global water productivity (WPoverall), output per unit irrigation water (OUI), and the percent of nitrogen fertilization obtained by irrigation water, were defined and calculated for years 2017 to 2020 in 104 persimmon and peach orchards. The results showed that most of the farmers irrigated below the crop water requirements, showing RWS and RIS values less than 1, and there was great variability among farmers, especially in WPoverall and OUI indicators.

Irrigation management transfer: The experience of the Río Dulce Irrigation Scheme, Argentina*

AbstractMany governments and international agencies have promoted irrigation management transfer (IMT) in order to reduce operations and maintenance costs and satisfy farmers' willingness to improve their irrigation service by self‐management. However, IMT has produced both satisfactory and unsatisfactory results. This paper presents a participatory research‐based assessment of IMT in a case study in Northwest Argentina. The study combined conventional irrigation performance assessment and a survey of farmers' perception of the water delivery service and willingness to participate in water users associations. The assessment compared two subsystems in the Río Dulce Irrigation District with different levels of management transfer. Water service in the subsystem where management had been transferred allowed flexible delivery schedules that facilitated a diversified cropping pattern, greater irrigation intensity, and resulted in more water use. Farmers in the transferred subsystem were more aware of the problems of the irrigation service than farmers in the non‐transferred subsystem. The perception of problems in the non‐transferred subsystem increased with the level of the farmer's professionalism and technical knowledge. The transmission of requests and complaints from farmers to managers was more transparent in the transferred subsystem than in the non‐transferred one.

Energy balance and irrigation performance assessments in lemon orchards by applying the SAFER algorithm to Landsat 8 images

In the semiarid conditions of the São Francisco River Basin, Brazil, irrigated fruit crops are replacing natural vegetation, being lemon highlighted by incentives for the national and international markets. This paper aimed to support the rational water management of lemon orchards under different irrigation systems under these conditions. We present a methodology based on the use of the visible and near infrared images from Landsat 8 (L8) satellite together with weather and actual yield data (Ya), to assess the energy balance components and irrigation performance indicators (IPI) by applying the SAFER (Simple Algorithm for Evapotranspiration Retrieving) in six commercial farms under different irrigation systems inside the basin in the northern Minas Gerais state, Southeast Brazil. The ET rates averaged 2.7 mm d−1, 2.9 mm d−1, and 3.7 mm d−1, for drip, micro sprinkler, and pivot irrigated orchards, respectively. The evaporative fraction (latent heat flux by the available energy) reached above 1.00 for localized irrigation (drip and micro sprinkler), and 1.30 for pivots, during the lemon phenological stages from fruit growth to harvest peaks. Pivot irrigation systems were not recommended under the semi-arid conditions, due to large water direct evaporated from the soil and air close to the surface. For drip and micro sprinkler irrigated orchards, crop coefficient curves were modeled based on the accumulated degree-days (DDac) to estimate lemon crop water requirements. Drip irrigated orchards presented better water productivity levels being recommended together with deficit irrigation strategies which could allow good lemon yields with saving water savings. The most important findings of the current research are that the SAFER algorithm can be applied to estimate crop ET with satellite images without the thermal bands which together with modelled Ya data, irrigation assessments can be carried out at high spatial resolution following the principles of precision agriculture. For replication of the methods in other regions, simple calibrations of the modelling equations can be performed to infer the specific environmental conditions.

Influence of Spatial Resolution on Remote Sensing-Based Irrigation Performance Assessment Using WaPOR Data

This paper analyses the effect of the spatial assessment scale on irrigation performance indicators in small and medium-scale agriculture. Three performance indicators—adequacy (i.e., sufficiency of water use to meet the crop water requirement), equity (i.e., fairness of irrigation distribution), and productivity (i.e., unit of physical crop production/yield per unit water consumption)—are evaluated in five irrigation schemes for three spatial resolutions—250 m, 100 m, and 30 m. Each scheme has varying plot sizes and distributions, with average plot sizes ranging from 0.2 ha to 13 ha. The datasets are derived from the United Nations Food and Agricultural Organization (FAO) water productivity through open access of remotely sensed–derived data (the Water Productivity Open Access Portal—WaPOR) database. Irrigation indicators performed differently in different aspects; for adequacy, all three resolutions show similar spatial trends for relative evapotranspiration (ET) across levels for all years. However, the estimation of relative ET is often higher at higher resolution. In terms of equity, all resolutions show similar inter-annual trends in the coefficient of variation (CV); higher resolutions usually have a higher CV of the annual evapotranspiration and interception (ETIa) while capturing more spatial variability. For productivity, higher resolutions show lower crop water productivity (CWP) due to higher aboveground biomass productivity (AGBP) estimations in lower resolutions; they always have a higher CV of CWP. We find all resolutions of 250 m, 100 m, and 30 m suitable for inter-annual and inter-scheme assessments regardless of plot size. While each resolution shows consistent temporal trends, the magnitude of the trend in both space and time is smoothed by the 100 m and 250 m resolution datasets. This frequently results in substantial differences in the irrigation performance assessment criteria for inter-plot comparisons; therefore, 250 m and 100 m are not recommended for inter-plot comparison for all plot sizes, particularly small plots (<2 ha). Our findings highlight the importance of selecting the spatial resolution appropriate to scheme characteristics when undertaking irrigation performance assessment using remote sensing.

A global analysis of irrigation scheme water supplies in relation to requirements

The performance of irrigation schemes around the world has been below expectations. The assessment of irrigation performance is an essential step towards improving agricultural water use. One of the primary performance indicators is the relative irrigation supply (RIS, the ratio between the amount of water delivered and the crop net irrigation requirements). This study presents a worldwide analysis of irrigation scheme performance by evaluating key attributes that influence the RIS. The analysis was based on a review of reports and scientific papers that yielded 264 cases belonging to 25 countries in six world regions. The database was subjected to two types of statistical analysis: k-means clustering and analysis of covariance (ANCOVA). The cluster grouped irrigation schemes which were characterized by low RIS and advanced irrigation technology. The ANCOVA showed that the RIS co-varied significantly with the variation in precipitation, delivery schedule, on-farm irrigation systems, distribution network, and region, but not with the crop. The ANCOVA also showed that modern pressurized on-farm irrigation systems and on-demand distribution systems significantly improve RIS. The ANCOVA general linear model had a good capacity to predict RIS with a coefficient of determination of R2 = 0.83.

Assessment of Irrigation Performance: A Case Study of Kırıkhan Irrigation Association

Bu çalışmada; Devlet Su İşleri tarafından inşa edilen ve Kırıkhan Sulama Birliğine devredilen sulama alanının performansı, su kullanım etkinliği, mali yeterlilik ve üretim etkinliği göstergeleri ile değerlendirilmiştir. Değerlendirmede; 2008-2013 yıllarına ilişkin Kırıkhan sulama birliği verileri kullanılmıştır. Çalışmada elde edilen sonuçlara göre; 2008 ve 2013 yıllarında sırasıyla birim sulama alanına dağıtılan sulama suyu miktarı 3735 m³ ha-1 ve 16651 m³ ha-1, birim sulanan alana dağıtılan toplam sulama suyu miktarı 5496 m³ ha-1 ve 13684 m³ ha-1, yıllık su temini oranı 0.70 ve 1.42’dir. Mali yeterlilik oranı en düşük 2008 yılında %57,5 en yüksek 2010 yılında %108,3, birim sulama alanına düşen işletme bakım yönetim masrafları en düşük 2010 yılında 81.52 $ ha-1 en yüksek ise 2009 yılında 141.96 $ ha-1, çalışan her bir personele düşen toplam yıllık masraf en düşük 2012 yılında 10055.19 $ kişi-1 en yüksek ise 2013 yılında 20183.23 $ kişi-1 ve su ücreti toplama performansı ise %34,42-92,08 oranında gerçekleşmiştir. Birim sulama alanına karşılık elde edilen gelir 528-4247 $ ha-1; sulanan birim alana karşılık elde edilen gelir 770-3719 $ ha-1; şebekeye alınan birim sulama suyuna karşılık elde edilen gelir 0.009-0.041 $ m-3 ve sulama oranı ise %33-89 arasında gerçekleşmiştir.

Modeling soil water balance and irrigation strategies in a flood-irrigated wheat-maize rotation system. A case in dry climate, China

Demand for irrigation water has been steadily increasing in arid regions where intensification of crop production is supported by flood-irrigation. An assessment of irrigation performance, water productivity, and irrigation schedules is critical to water conservation in dry climates. In this study, we conducted a field experiment to compare soil water balance in a flood-irrigated wheat-maize rotation system during the growing season of 2015–2016. We then modeled the soil water balance and improved irrigation strategies by coupling Hydrus-1D with the CROPWAT model, and using evapotranspiration calculated from climatic data. The calibrated Hydrus-1D model was used to simulate the temporal and spatial variation of evapotranspiration and deep percolation based on measured soil water distribution of soil profiles in the unsaturated zone. Results showed that using soil hydraulic parameters from inversion modeling can simulate soil water flow in multi-layer soil during a crop growing season. Simulation results indicated that about 36.6 and 40.6% (478.6 and 680.1 mm) of total water input in 2015 and 2016, respectively, was consumed by evapotranspiration. Furthermore, simulated deep percolation amounted for approximately 32.3 and 42.9% (403.9 and 696.6 mm) of the total amount of irrigation water in 2015 and 2016, respectively. These results indicated that only a small proportion of irrigation water was used by crops for transpiration. In addition, irrigation performance indicators such as relative water supply, relative irrigation supply, depleted fraction, and overall consumed ratio values indicated poor performance of irrigation practices in the study area. Particularly, crop yields did not increase with increases in irrigation water in flood-irrigated fields during the last ten years. Results of the CROPWAT model indicated that combinations of a fixed irrigation depth and timing, of 40 mm every 10 days, and 50 mm every 10 days were reasonable for wheat and maize, respectively, given the sandy soil in the study area. The improved irrigation strategies will limit water irrigation loss to 20% without significant effects on crop yields. This study provides an alternative approach for estimating deep percolation and crop water requirements supporting management efforts in water conservation in dry climates.

Global Satellite-Based ET Products for the Local Level Irrigation Management: An Application of Irrigation Performance Assessment in the Sugarbelt of Swaziland

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.

Assessment of Irrigation Performance in Large River Basins under Data Scarce Environment—A Case of Kabul River Basin, Afghanistan

The Kabul River basin (KRB) of Afghanistan, a lifeline of around 10 million people, has multiplicity of governance, management, and development-related challenges leading to inequity, inadequacy, and unreliability of irrigation water distribution. Prior to any uplifting intervention, there is a need to evaluate the performance of irrigation system on a long term basis to identify the existing bottlenecks. Although there are several indicators available for the performance evaluation of the irrigation schemes, we used the coefficient of variation (CV) of actual evapotranspiration (ETa) in space (basin, sub-basin, and provincial level), relative evapotranspiration (RET), and temporal CV of RET, to assess the equity, adequacy, and reliability of water distribution, respectively, from 2003 to 2013. The ETa was estimated through a surface energy balance system (SEBS) algorithm and the ETa estimates were validated using the advection aridity (AA) method with a R2 value of 0.81 and 0.77 at Nawabad and Sultanpur stations, respectively. The global land data assimilation system (GLDAS) and moderate-resolution imaging spectroradiometer (MODIS) products were used as main inputs to the SEBS. Results show that the mean seasonal sub-based RET values during summer (May–September) (0.37 ± 0.06) and winter (October–April) (0.40 ± 0.08) are below the target values (RET ≥ 0.75) during 2003–2013. The CV of the mean ETa, within sub-basins and provinces for the entire study period, has an equitable distribution of water from October–January (0.09 ± 0.04), whereas the highest inequity (0.24 ± 0.08) in water distribution is during early summer. The range of the CV of the mean ETa (0.04–0.06) on a monthly and seasonal basis shows the unreliability of water supplies in several provinces or sub-basins. The analysis of the temporal CV of mean RET highlights the unreliable water supplies across the entire basin. The maximum ETa during the study period was estimated for the Shamal sub-basin (552 ± 43 mm) while among the provinces, Kunar experienced the highest ETa (544 ± 39 mm). This study highlights the dire need for interventions to improve the irrigation performance in time and space. The proposed methodology can be used as a framework for monitoring and implementing water distribution plans in future.

Evaluation of the Water Allocation and Delivery Performance of Jiamakou Irrigation Scheme, Shanxi, China

Irrigation performance assessment is an important step in ensuring sustainable agricultural development and improving the capacity of irrigation water management. In this paper, we examined irrigation water management in the Jiamakou Irrigation Scheme in the province of Shanxi (China) using four typical indicators, namely adequacy, efficiency, dependability, and equity. These indicators were calculated both globally and by grouping the data according to different irrigation processes (water allocation and water delivery). Results show that water was poorly allocated, and crop water requirements calculated through the FAO56 Penman-Monteith method was not met timely by scheduled water. They indicate that the overall performance of the scheme was relatively poor, owing to dismal water allocation. Nevertheless, water delivery performance was good, indicating that the scheme was able to deliver adequate and dependable water in an equitable and efficient manner. Our findings suggest that farmers should be trained in allocating irrigation water. The study provides insights into the current behavior of the irrigation scheme and may be used as a base for improvement of irrigation performance.

Improvement of the irrigation performance in Water Users Associations integrating data envelopment analysis and multi-regression models

Irrigation performance assessment is particularly important in the Water Users Associations (WUAs) operating in Calabria (Southern Italy), where collective irrigation service suffers from poor performances both from an operative and economic point of view. For many years Data Envelopment Analysis (DEA) has been proposed for the diagnosis of Water Users Association performance; however, the number and type of related performance indicators must be selected with caution to avoid misleading and unrealistic results.In this paper, we propose to apply DEA to a limited but significant set of performance indicators and to couple it to Multiple Regression Analysis by Principal Component Regression (PCR). The proposed methods were applied to evaluating the system operation and financial performances of ten of the eleven WUAs operating in Calabria (Southern Italy) to indicate potential improvements.The analysis of the current performance indicators collected throughout five years (2011–2015) showed that in Calabrian WUAs the irrigation service is underutilised, and water delivered to crops is always in excess; the cost recovery of WUAs is very low, because of staff costs and low fee collection. DEA identified five inefficient WUAs and took the remaining five organisations as reference for performance improvement. The input-oriented DEA coupled to PCR has suggested reducing water usage, management and personnel costs and water fees, by increasing the irrigated area and the irrigation service coverage. The output–output oriented DEA coupled to PCR predicted a high increase of the cost recovery capacity of the inefficient WUAs, but in this case the improved scenario required an abnormal increase (10-fold) of the irrigated area, which may be basically unfeasible.Overall, the integration of DEA with multi-regression models and their implementation in the case study, using a limited set of easy-to-survey performance indicators, appears to be a powerful and easy tool for decision makers in the irrigation sector.

A user-centred approach to irrigation performance: drip irrigation in the Khrichfa area, Morocco

ABSTRACTConventional irrigation performance assessments narrowly confine the possible effects of using drip irrigation to what it is designed to do, i.e., improve efficiencies. While helpful in the design, such assessments leave little scope for the possibility that irrigators adopt the technology for reasons other than improving efficiencies. Using a case study about how irrigators in the farmer-managed Khrichfa Canal in Morocco engaged with drip irrigation, we propose a user-centred approach to irrigation performance. Use of this approach opens up the possibility that a technology is used and mobilized for other reasons than only those intended in the design process.

Farm Level Assessment of Irrigation Performance for Dairy Pastures in the Goulburn-Murray District of Australia by Combining Satellite-Based Measures with Weather and Water Delivery Information

Pasture performance of 924 dairy farms in a major irrigation district of Australia was investigated for their water use and water productivity during the 2015-2016 summer which was the peak irrigation period. Using satellite images from Landsat-8 and Sentinel-2, estimates of crop coefficient (Kc) were determined on the basis of a strong linear relationship between crop evapotranspiration (ETc) and vegetation index (NDVI) of pasture in the region. Utilizing estimates of Kc and crop water requirement (CWR), NDVI-dependent estimates of Irrigation Water Requirement (IWR) were derived based on the soil water balance model. In combination with daily weather information and seasonal irrigation water supply records, IWR was the key component in the understanding of current irrigation status at farm level, and deriving two irrigation performance indicators: (1) Relative Irrigation Water Use (RIWU) and (2) Total Irrigation Water Productivity (TIWP). A slightly higher proportion of farm irrigators were found to be either matching the irrigation requirement or under-watering (RIWU ≤ 1.0). According to TIWP, a few dairy farms (3%) were found to be in the category of high yield potential with excess water use, and very few (1%) in the category of limited water supply to pastures of high yield potential. A relatively high number of farms were found to be in the category where excess water was supplied to pastures of low-medium yield potential (27%), and farms where water supply compromised pastures with a sub-maximal vegetation status (15%). The results of this study will assist in objectively identifying where significant improvement in efficient irrigation water use can be achieved.

Field assessment of basin irrigation performance and water saving in Hetao, Yellow River basin: Issues to support irrigation systems modernisation

Water-saving irrigation needs to be implemented in Hetao irrigation district to help satisfying the demand by other users in the Yellow River basin. Aiming at assessing the potential irrigation performance and water saving at farm level, a set of traditional basins and another of precision-levelled basins cropped with maize, wheat and sunflower and managed by farmers were evaluated. Data were collected to characterise the basin sizes, microtopography, inflow rates, advance and recession times, cut-off time and soil water content. In addition, families of infiltration curves were derived from field observations and subsequent use of model SIRMOD. Infiltration was higher for the precision-levelled basins and decreased from the first to the next irrigation events. Infiltration data were used to support the computation of distribution uniformity (DU), beneficial water use fraction (BWUF) and deep percolation (DP). For traditional basins, DU and BWUF were low and DP was high. When precise land levelling was practised, DU increased greatly to near 94% but BWUF improved little, because irrigation scheduling was inadequate leading to excessive water application; however, non-negligible water saving was achieved for maize and wheat since they have higher irrigation demand. In contrast, simulating the application of an appropriate irrigation scheduling through adjusting the cut-off time led to an approximately unchanged DU but BWUF greatly increased and DP reduced to 10% on average. This condition represents a potential water saving of 34–39%; however its achievement requires improved design of farm systems, appropriate irrigation water deliveries and scheduling, and the support and training of farmers.