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One of the main challenges in super high-density olive is maintaining hedgerow structure suitable for mechanical harvesting. Deficit irrigation strategies (DI) can contribute to this maintenance. In this study, three DI treatments at 50% of the Control (DI-1: budbreak to pre-bloom, DI-2: fruit set to pit hardening, and DI-3: pit hardening to harvest) were applied to 6-year-old Arbequina hedgerows in a semi-arid environment of Argentina over three consecutive seasons. The mean applied water reduction was 12% for DI-1 and 16% for DI-2 and DI-3, compared to Control (100% of ETc throughout the cycle). DI-3 achieved the narrowest hedgerows at harvest, where canopy height was responsive to irrigation and canopy width was affected by fruit load but not by the irrigation regime. DI-1 demonstrated similar fruit and oil yields to Control throughout the experiment, while DI-2 only had comparable yields to Control in Off-season. DI-3 had the lowest oil yields, averaging – 27% in Off and On-seasons. The fruit number was similar among treatments in all seasons, indicating that differences in final yield were related to fruit size and oil concentration. Further studies are needed to determine the optimal duration and intensity of the water deficit for DI-3. [ABSTRACT FROM AUTHOR]

Water is a finite resource but an essential one. The continuously increasing demand leads to competition and conflict over limited resources. Syria, Jordan, and Israel compete over the water resources in the transboundary Yarmouk River basin where two water agreements dictate the allocation of water. The two arrangements are far from being efficient and fair while little cooperation is being made over sharing the resources that are being over-exploited. In this study, water sustainability was investigated under projected developments and trends based on the current use and allocation regime in the watershed using several scenarios. A one bucket soil moisture model was adopted and optimized in order to fully represent the ever-changing hydrology of the basin using the Water Evaluation and Planning (WEAP) tool. Demands along with the existing water infrastructure and their operation were modelled despite the lack of many data and the huge uncertainty in some. Simulation of business as usual scenario showed that continuing with the current use cannot be sustainable in the short and long term. The growth of both agriculture and population produced huge water shortages in all demand sectors. Under climate change scenarios RCP 4.5 and RCP 8.5, surface water availability and the retention of dams reduced significantly. The share of Jordan from the Yarmouk River was the most vulnerable to climate change impacts. Enhancing irrigation efficiency and a more stable population growth based on the UN medium variant population projection showed improvements in water coverage within all demand sectors. Analysis of future scenarios suggests that water shortage is expected in all riparian states of the basin but can be mitigated by reducing demands. [ABSTRACT FROM AUTHOR]

In this study, the water-food-energy nexus in the Lake Urmia basin was investigated to establish a balance between water and energy consumption, aiming to protect the environment and ensure food security. The research was conducted on 17 farms located in different parts of the Lake Urmia basin, encompassing the predominant crops in the region as well as a variety of irrigation systems. An integrated water-food-energy nexus index was developed, which included irrigation application efficiency, water productivity, energy ratio, energy efficiency, various water footprints and the carbon footprint. The implementation of drip irrigation systems can significantly reduce potential harm to water and energy resources, and the environment. [ABSTRACT FROM AUTHOR]

Groundwater resources are the most reliable freshwater supply in arid regions where many aquifers face dramatic depletion due to natural and anthropogenic causes. The annual average rate of decline of groundwater level is about 1.65 m. This research focuses on an aquifer that suffers from severe groundwater stress, and it aims to identify the main causes of the stress and to understand the effects of climate change and human activity. Monthly data on groundwater level, precipitation, temperature, river discharge, evapotranspiration, soil moisture, and vegetation cover were collected from 2000 to 2020. The results indicate that declining groundwater levels mainly resulted from the expansion of vegetation cover rather than changes in hydro-climatic variables. Finally, this work highlights how significant financial investment in improving irrigation efficiency in the absence of socio-economic plans, education, awareness, and monitoring programmes unproductively resulted in the expansion of agricultural activities rather than preserving groundwater storage. [ABSTRACT FROM AUTHOR]

Using a three-infrastructures (grey, soft, and green) framework, we examined key risks to water availability and quality in the Murray-Darling Basin, Australia. These risks include increased irrigation efficiency, without a quantitative knowledge of the impact on water flow pathways, particularly return flows, growth in farm dams and floodplain harvesting, and unsustainable management of salinity. Critical to mitigating these risks are the metering, monitoring, and auditing of water flows, effective linkages between evidence and analysis, and accountability of decision-makers operating in the public interest. We contend that these approaches need to be supported by innovative risk assessments, which are fit-for-purpose under the MDB Plan, wherein the 'who, what, when and where' are assessed in relation to cumulative, systemic, and cascading risks from human actions. [ABSTRACT FROM AUTHOR]

This study examines the primary issues that Egypt's irrigated agriculture faces in the land reclamation project in the Western Desert and potential solutions to ensure groundwater sustainability. Reduced groundwater quantity and quality, low adoption rates of precision irrigation systems, and increased energy for groundwater abstraction were recognized as challenges. Irrigation efficiency improvements, transitioning to high water-use efficiency crops, wastewater reuse, and groundwater monitoring have all been mentioned as viable water management options for maintaining irrigation well-planned use during the project's age (100 years). Adoption and acceptance of these ideas by farmers in the impacted agricultural regions will determine their success. [ABSTRACT FROM AUTHOR]

The impact of wide ridge-furrow planting on maize production are mostly unexplored. The field experiment was conducted to study the effect of four ridge width on growth and water use efficiency (WUE) of maize (Xianyu 335) with same furrow spacing and basin planting with same spacing as conventional planting (CP). Compared with the CP, ridge-furrow (RF) increased plant height but reduced stem diameter and dry matter weight. The wide ridge under RF was beneficial to the high leaf area and dry matter accumulation. However, the least plant spacing generated stress on stem growth with a wider ridge (RF180). The maximum grain yield (6573 kg ha−1) and WUE (23.0 kg mm−1 ha−1) were obtained under RF120, which were increased by 15.9% and 33.9% compared with CP. Irrigation efficiency and irrigation water use efficiency (IWUE) under RF system was improved 1.20–1.43 times and 1.89–2.45 times compared with CP, which was mainly due to the lower volume of irrigation water (decreased by 34.5–42.9%) under the RF system. Our results highlight that the RF method can be used as a water-saving method with ridge width up to 120 cm that lead to high yields of maize. [ABSTRACT FROM AUTHOR]

Globally irrigation subsidies are utilized to boost modernization and increase irrigation efficiency. This paper examines the effects of the irrigation subsidy programme in Chile by reviewing 32 years of allocations and exploring the drivers and consequences of the subsidy programme with a clear market approach based on competition and a state risk-free strategy. Our analysis reveals that, despite the flexibility in targeting, the results indicate an uneven allocation to smallholders' detriment, a state inability to identify farmers' needs, market concentration and a bias towards agricultural expansion. As long as the programme remains unaltered, it will threaten agriculture and water resources' sustainability. [ABSTRACT FROM AUTHOR]

Hamun Lake, the greatest (>8500 km2) freshwater in the Iran plateau, has almost entirely dried over the last 20 years. The flow of the Hirmand (or Helmand) River, the most important feeding river, has decreased from 4.0 to 1.9 km3 in the border of Iran-Afghanistan. In this river basin, the annual water consumption for irrigation is over 90% of the total consumed water. This study aims to calculate the increase in agricultural water consumption in the last two decades. Due to the lack of in-situ data across Afghanistan (including ∼80% of the studied area), this research utilizes remote-sensing. Using Google Earth Engine, land use maps for the years 2002, 2008, 2013, 2017, and 2021 were developed by a supervised classification scheme. Since 2002, it was found that the cropland area has increased from 2008 to 5475 km2. Most cropland has been developed around the Kajaki dam. Based on the Penman-Monteith-Leuning Evapotranspiration version 2 (PML V2) actual evapotranspiration (AET) data (our model assumes the irrigation efficiency equal to 0.3), the annual consumed water has increased from 2 to over 6 km3 in the last two decades. The presented framework in this study can be recommended for other ungauged basins. [ABSTRACT FROM AUTHOR]

Two of Tony Allan's phrases – big water and accountants will save the world – invite me to argue that irrigation is poorly served when its hydrology is seen solely as big or via accounts. While big applies because irrigated areas deplete considerable volumes of water, irrigation systems contain many more water relations, behaviours and puzzles. In this problematic, environmental, social and governance (ESG) and water accountants and accounts will become a dominant force. This is worrying for the degree to which individual irrigation systems are rendered into catchment-level accounting abstractions, removing us from a more vital, multidisciplinary, cross-scale and action-oriented approach. [ABSTRACT FROM AUTHOR]

Vegetables are important constituents of Indian agriculture and nutritional security of the people. India no doubt has diverse agro-climatic conditions with distinct seasons that are supportive for growing a wide range of vegetables and offers a lot of potential to enhance their production by adopting innovative technologies. Despite largest irrigation network in India, irrigation efficiency is merely 40% and water and nutrient use efficiencies are very low. Also bringing more area under irrigation will largely depend upon the efficient use of water and other resources. In this context, micro irrigation with fertigation especially in vegetable crops has proven a win-win technology in enhancing water and nutrient use efficiencies and in turn higher yield potential thereby achieving the prime objective of 'more crop per drop'. The technology provides precise water control, dissolved fertilizers, application facilities and thus more resilient and cost effective. Moreover, mulching along with drip irrigation and fertigation add feather to this technology by controlling weed population and increasing overall efficiency of the system. Mulching insulates the soil, provides a buffer from cold and hot temperature, reduce deterioration and erosion of soil and also checks water evaporation. This review presents the finding of various researchers involving the influence of drip irrigation, fertigation and mulching on different vegetable crops. It is evident from the studies that drip fertigation practice alone or in combination with mulching offer a huge potential in enhancing crop yields, quality, growth, water and nutrient saving in comparison with other conventional tools of irrigation and fertilization. [ABSTRACT FROM AUTHOR]

The present study aims at estimating net and gross water requirements of eight major irrigated crops in the agro-ecological regions Tina Plain (AER 1), and East South ELKantara (AER 2) in Egypt using FAO-CROPWAT 8.0 and its attached meteorological parameters CLIMWAT 2.0 model. Historical weather data at Ismailia and Port Said stations for 40 years (1975 to 2014) were recalled from the CLIMWAT 2.0. The net irrigation requirements for berseem clover, barley and cotton in AER 1 were computed at 612 mm, 283 mm and 901 mm, respectively, while, in AER 2, the corresponding values were 738 mm, 287 mm and 1113 mm showing a 19% increase. District water balance scenarios show for crop pattern with maximum net and gross irrigation water requirement, and irrigation efficiencies 40% and 60% in AER 1 and AER 2, respectively, indicates 22.1% increase above the licensed water limit, crop pattern with minimum net and gross irrigation requirements indicates 23.1% saving of allocation water limit, and the current crop pattern indicates 8.1% saving. Therefore, better water management should be adapted to focus on improving irrigation efficiency and cultivating crops with lower water need, such as green beans, wheat, barely, sugar beet, and tomato. [ABSTRACT FROM AUTHOR]

Six plots include three plots of solid-set sprinkler and three plots of border irrigation methods in Kangavar plain (Iran), were evaluated under farmers' management standards. Wheat was grown in each of the plots and all the irrigation events were evaluated. The average values of irrigation indexes, distribution uniformity, potential application efficiency of the low quarter, application efficiency of the low quarter, application efficiency, deep percolation ratio, adequacy of irrigation, and water requirement efficiency in border-irrigated plots were 80.4%, 80.4%, 69.1%, 80.5%, 19.5%, 53.1%, and 80.8%, respectively. Those values indicated much better performance than the average values for the movable solid-set sprinkler-irrigated plots, which were 55.8%, 44.7%, 37.2%, 41.5%, 38.6%, 85.0% and 96.5%, respectively. So the system design and the farmers' management are suitable with border irrigation in accordance with the experiences they have gained with time. That was not the case for the movable sprinkler irrigation system, in which the performance indexes are below the recommended minimum values. Therefore, the efficiency of an irrigation system is not independent of its management, and the farmer's skill on the irrigation system is one of the most important indices for selecting a suitable irrigation system. Also, improving farmer's management is the most appropriate way for improving irrigation performance. [ABSTRACT FROM AUTHOR]

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]

This study examines the importance of generating proper water accounts for large gravity-based irrigation schemes in order to assess scheme performance. It shows how the use of simplistic criteria used to assess the performance of gravity-based irrigation schemes can lead to an underestimation of the role they play in enhancing food security and agricultural production in countries such as India, which has established a huge network of irrigation canals. The paper offers specific suggestions on improving irrigation statistics that, in turn, can help in better evaluation of the returns on investments of public surface irrigation schemes. [ABSTRACT FROM AUTHOR]

In this study, contributions of climate change and human activity to streamflow changes were estimated to enable decision makers to develop adaptation strategies for management of regional water resources. Flow trends and climate variables were analysed with the Mann-Kendall method. The year 1986 was selected to perform the Pettitt test to identify the change point of the runoff time series. Then, three methods were used for impact differentiation: climatic elasticity, least-squares support-vector machine (LS-SVM), and the soil and water assessment tool (SWAT). The results showed that climate change (38–67%) and human activities (33–62%) influence runoff reduction. Thus three management scenarios are introduced to reduce the effects of climate change and human activity: (1) adjusting wheat and barley cultivation levels; (2) maintaining wheat and barley cultivation levels and replacing other crops with potatoes; (3) increasing irrigation efficiency. All scenarios showed an increase in runoff, but the first scenario had the most impact. [ABSTRACT FROM AUTHOR]

The article is an introduction to the first issue of Water International in 2024. It mentions upcoming events and themes related to water governance. The articles in this issue cover various topics, including a paradigm shift in sanitation, household inadequacy of water supply and sanitation services in Brazil, access to water in peri-urban areas of Lima during the COVID-19 pandemic, the water-food-energy nexus in the basin of Lake Urmia in Iran, and the interrelations between water and conflict in the Inner Niger Delta in Mali. The article also mentions upcoming special issues on urban water use in irrigation and basin management. [Extracted from the article]

To date, most studies on the role of women in water management have focused on local communities in developing countries, within which women are more vulnerable to hydrological risk. This study emphasizes the need to investigate the preferences of women in industrialized nations. The results of a representative opinion survey in Andalusia (Spain) reveal that, when it comes to water management, women tend to think primarily in domestic terms whereas men prioritize the efficiency of irrigation systems. In Andalusia (a region under severe risk of hydrological stress) irrigation has a much greater impact on the efficiency of water use than any other factor. To explain these differences of opinion, this study analyses the gender gap in terms of environmental concern and political knowledge. The results suggest that women's preferences relate not only to their greater environmental proactiveness in the domestic sphere but also to political-knowledge-related variables. [ABSTRACT FROM AUTHOR]

Improvement of efficiencies of N fertilizer and irrigation water is needed for large-scale market-oriented rice cultivation without puddling practice as in American continents. Effects of reductions of N fertilizer and irrigation water on grain yield of drill-seeded rice on zero-leveled fields were quantified across five N levels (220, 180 [two sources with 5 or 3 splits], 140, and 0 kg N ha−1) and three irrigation strategies (irrigating every 3, 6, or 8 days; W1, W2, and W3, respectively) in dry and wet seasons during an El Niño event in Central Colombia. Reducing the N application rate from 180 kg N ha−1 to 140 kg N ha−1 (22% reduction) did not reduce yield in either season in spite of slightly reduced N uptake, owing to increased N use efficiency in all irrigation strategies. Three split of N fertilizer with slow release urea (180 kg N ha−1) and with basal organic amendment did not reduce yield compared with the conventional 5 split method. Yield in dry season reduced under the 2 water-saving strategies (W2, W3) almost proportionally to the reduced water supply (irrigation + rainfall) by flowering. In wet season, yield in mild water saving (W2, with 26% water saving) was similar to conventional irrigation management (W1), leading to its highest water productivity. Physiological parameters (e.g. stomatal conductance, total N uptake) were greater in wet season than in dry season. This study showed potential reduction of N fertilizer and conditions of climate for water-saving in drill-seeded rice production in Colombia. [ABSTRACT FROM AUTHOR]

To foster poverty reduction in drought-prone Araucanía, the Chilean Irrigation Commission is planning an important expansion of irrigated areas. Scenarios incorporating climate change (2030–2059) were simulated for a pilot basin using the WEAP water allocation model, showing that larger irrigated areas, coupled with higher temperatures and less precipitation, are likely to cause severe seasonal water scarcity. As decision support for the planning of effective measures to increase drought resilience, we modelled the construction of two upstream reservoirs combined with higher irrigation efficiency. We find that unmet water demand can be reduced by up to 97.7% by these measures. [ABSTRACT FROM AUTHOR]

To evaluate the forage yield and quality of Berseem and Persian clover cultivars, a two-year experiment was conducted during two growing seasons (2017–2018 and 2018–2019). Irrigation was the main factor, including full irrigation (I100), moderately limited (I75), and severely limited irrigation (I50). The sub-factor consisted of ten cultivars of clover, five of which were Persian clover (Pars, Aleshtar, Eghlid, Harat, and Zabol) and five cultivars of Berseem clover (Karaj, Elite, Ekinaton, Vienna, and Alex). The results showed that the highest dry matter (DM) and crude protein (CP) yield under all irrigation levels were obtained from the Berseem clover cultivars. Imposing limited irrigation reduced the DM yield, digestible dry matter (DDM) yield and content, CP yield, dry matter intake (DMI), and relative feed value (RFV) of forage, whereas the content of CP, water-soluble carbohydrates (WSC), neutral detergent fiber (NDF), and acid detergent fiber (ADF) increased. Irrigation water use efficiency (IWUE) for DM, DDM, and CP yield under limited irrigation were also increased. Comparison of two groups of Persian and Berseem clover cultivars also showed that with increasing drought stress intensity, in Berseem cultivars, DM yield, DDM yield and content, and RFV decrease was higher. Increasing IWUE under limited irrigation was higher in Persian cultivars for DM and DDM yield. Overall, Berseem clover had higher forage yield and water use efficiency in all irrigation regimes, and the forage quality of this species showed more sensitivity to drought. Abbreviations :I100, I75, and I50, full, moderately limited, and severely limited irrigation (equivalent to 100, 75, and 50% weekly evaporation and crop water requirement, respectively); DM, dry matter; CP, crude protein; ADF, acid detergent fiber; NDF, neutral detergent fiber; DDM: digestible dry matter; WSC, water-soluble carbohydrates; DMI, dry matter intake; RFV, relative feed value; IWUE, irrigation water use efficiency. [ABSTRACT FROM AUTHOR]

It is also a frequent topic in these pages, so to mark the Year of Groundwater we have compiled a list of dozens of recent articles, plus two special issues, that feature groundwater (see https://www.iwra.org/water-international-groundwater-articles/). Dear Readers, We are pleased to offer in our second open issue of 2022 an outstanding collection of submissions, grouped into thematic sections of groundwater, water governance and transboundary waters. The authors develop a much-needed index to assess groundwater management in Iran. [Extracted from the article]

Concern over increasing water scarcity has led to the introduction of the concept of agricultural water productivity and an emphasis on interventions to achieve 'more crop per drop'. Yet, a strong debate continues on how the concept is to be defined and used. Drawing largely from the irrigation literature, the origins of the concept and its methodological developments are reviewed, and its use in applied work over two decades is discussed. Based on this analysis of conceptual and applied research, key insights into the concept's contributions and limitations are presented, as well as opportunities for further refinements. [ABSTRACT FROM AUTHOR]

The Small Dams Organization has constructed 55 small dams in the rain-fed region of Pothwar Plateau, Punjab in Pakistan. A study was conducted on the Pothwar Plateau during 2019 to investigate the economic importance of small dams in the region, using Khasala and Jawa dams as the case study. The study tasks included: (i) a broad evaluation based on the performance of small dams in Pothwar Plateau, and to analyze the economic benefits of small dams to farming communities; (ii) a comparative analysis of the Khasala and Jawa dams on the Pothwar Plateau to identify the factors that influence agriculture production on irrigated (I) and non-irrigated (NI) farms in the area; and (iii) identification of key issues in order to identify potential options to improve agriculture production on the Pothwar Plateau. Data was collected through field observations, questionnaires, key informant interviews, and formal and informal discussions with farmers and was collated and reviewed quantitatively and qualitatively. It was found that the minimum water pricing is the basic reason for wastage and excessive water consumption. The cost of collecting water-charges from farmers is greater than the water-charges which are received. This has resulted in delayed maintenance of the irrigation systems which exacerbates water losses. It was also found from the survey of farmers of irrigated land and non-irrigated land that irrigation increases wheat yield by 15%, maize yield by 42%, vegetable yield by 41–44% and fodder yield by 60%. The availability of wells on non-irrigated farms means that these farmers could access timely irrigation, otherwise, their productivity gap would be greater if they were forced to rely on rainfall only. Issues of concern which were identified included: (i) illegal diversion of irrigation water by influential farmers; (ii) inadequate maintenance of irrigations systems and (iii) inefficient on-farm irrigation practices which contributed to a total irrigation efficiency in the irrigated areas of less than 30%; (iv) water rights and a water rotation systems are not implemented in the study area and (v) there is no water user association to deal with the water channels in the region which leads to clashes between users over the water distribution. A number of strategies that should be implemented to enhance agriculture production and efficient use of water resources are also identified. [ABSTRACT FROM AUTHOR]

Concerns have been raised that the use of infrastructure and water efficiency projects to recover water entitlements for the environment in the Murray–Darling Basin (MDB) could be undermined by a reduction in return flows to rivers. Water use efficiency changes prior to 2009 had already reduced surface return flows. A dimensionless and normalised variable, connectivity factor (CF), has been used to analyse the cumulative impact on river flow from actions that alter groundwater recharge or extraction. CF is objectively estimated from existing modelling outputs for three large alluvial groundwater systems in south-eastern MDB relevant to a major water use efficiency program. Lower values of CF (0.05–0.45) imply lower reductions of return flows, less impacts on recovered water entitlements, with impacts more likely to be managed adaptively within current water management plans. The study should help allay concerns by explaining why previous estimates had been overly high. [ABSTRACT FROM AUTHOR]

This article sharpens consideration of aspects of policy transfer to address climate change and gives greater attention to the context that might support efficient adaptive resilience. Using the example of Australian reforms to water policy, we evaluate how different elements of policy proved more (less) successful in facilitating efficient adaptation to climate variability and thus expose elements that might be more (less) attractive as candidates for policy transfer. Overall, we find that Australian policy reforms in the water sector provide useful guidance in some instances and not others. Establishing caps on extraction, flexible water markets and individual carry over rights generally facilitated flexible and efficient adaptation, and could be transferred. Related policy concepts, like formulating clear water planning rules and entitlements, are worth considering for implementation elsewhere, even if the groundwork on governance is a prerequisite. We also note the importance of shaping drought responses from government in such a way as not to distort the incentives for individual adaptation, and there is some evidence of this working in the Australian setting. Achieving transferability of these policies, however, may be a challenge. Australian policies around 'hard infrastructure' investments have generally proved less desirable and ideally should not be considered as a roadmap. These relate specifically to: (1) extravagant augmentation of urban supply; (2) using infrastructure to supposedly improve irrigation efficiency for environmental water provision; and (3) governments' infrastructure responses after flooding. None of these approaches is consistent with the aim of fostering adaptation to a more variable climatic future. Key policy insights Australian water policies that have focussed on capping water extractions, development of flexible markets and specifying rights to allow greater flexibility have generally worked well against a changing climate, and could be transferred. The development of clear planning rules and entitlements also proved important, although the conditions to favour transfer are difficult to engender. Policies dealing with hard physical infrastructure have proven problematic and their adoption elsewhere is discouraged, even if transfer is more amenable. Encouraging more individual adaptation to flooding is a particularly significant challenge, even in a country renowned for drought. [ABSTRACT FROM AUTHOR]

We examine water governance in the Murray-Darling Basin using the frameworks of rent-seeking and regulatory capture. These frameworks are used to evaluate two government programmes intended to ensure an environmentally sustainable level of water diversions in the basin: targeted one-on-one purchases of water entitlements from designated sellers; and subsidies for irrigation infrastructure to increase irrigation efficiency. Deficiencies in delivering the stated environmental goals of both programmes, and questions about their 'value for money', are highlighted. Specific recommendations are provided about how to mitigate both rent-seeking and regulatory capture of water reform initiatives in large river basins. [ABSTRACT FROM AUTHOR]

Zayandehroud River Basin has been experiencing a rapid industrial and agricultural development which caused severe water crisis with several environmental and social consequences. This study presents a dynamic model to analyse the interaction of groundwater and surface water resources in the basin by applying various conjunctive management scenarios. Different scenarios for the management of the Zayandehroud River Basin under the conjunctive use of surface and groundwater resources were evaluated. The water evaluation and planning (WEAP) and the MODFLOW models were used as the planning tool to assess the status of the basin under the designed scenarios and to simulate groundwater resources considering dynamic link between them. The proposed scenarios were based on a demand and supply management approach and accommodate changes in consumption patterns and irrigation efficiency. Finally, the designed scenarios were evaluated based on economic, social, and environmental criteria using the multi-criteria decision-making (MCDM) method. Our analysis indicated that under proper management policies the aquifer withdrawal would reduce from 74% to 62% leading to enhancement of basin sustainability. [ABSTRACT FROM AUTHOR]

Australia's water management futures are again under discussion as drought impacts and bushfires hit communities. Water and ecological system limits are being reached resulting in fish kills and dwindling water levels in storages. Awareness is also rising around the inequities in current water governance regimes for First Peoples across the Australian continent and beyond. Here we provide a brief overview and research on: the ingenuity of Indigenous waterscape and landscape knowledge and practices to care for country and community, including the development of agricultural systems and sophisticated fish and eel trapping systems that are thousands of years old; the devastating impacts of colonisation on First Peoples, their country and ability to maintain some cultural practices; and the ongoing contestation over water governance, right from Federation, including the eight waves of water reforms in the Murray-Darling Basin. Current challenges and needs for reform are also presented including: hydrological scientific uncertainties, such as around return flows and their adjustment due to irrigation infrastructure efficiency increases, and new design methodologies, such as for flood estimation inputs to hydraulic models; adjusting current governance regimes of sustainable diversion limits and water markets to provide alternative value to Australia, beyond economic value drivers, that better respond to the benefit of all basin communities in the face of ongoing extreme climate variability and climate change; and determining positive ways forward for truly valuing and allowing First Peoples' knowledge, practices, culture and law to provide a basis for developing the next waves of Australia's water management reform journey. [ABSTRACT FROM AUTHOR]

We use published water balance data from irrigated cropping to show that water entitlements acquired for environmental purposes through water infrastructure subsidies in the Murray–Darling Basin, Australia, have resulted in smaller increases in net stream and river flows than is estimated by the Australian Government, and may even have reduced net stream and river flows. Two key policy implications arising from our results are: (1) subsidies to improve irrigation efficiency so as to increase stream and river flows must employ water accounting so that the effects on return flows are known and the volume of water extracted for irrigation is adjusted to achieve desired stream and river flows; and (2) if the net increases in stream and river flows in the MDB are much less than estimated by the Australian Government, water infrastructure subsidies to increase irrigation efficiency may have compromised the delivery of key objects of the Water Act (2007). [ABSTRACT FROM AUTHOR]

Maize is the most important crop grown in Mexico, with more than one-third of total production coming from irrigated fields. We compute irrigation energy use and associated greenhouse gas emissions of different irrigated maize systems in Mexico. Calculations were based on National Agriculture and Forestry Census 2007 microdata, irrigation water requirements estimated from state-level climate data, and energy and emission coefficients from the literature. Weighted average irrigation energy and related emissions are in the range of 1.0–31.6 GJ/ha and 62.0–2,019.9 kg CO2e/ha, respectively, while country-scale estimates amount to 4.8 PJ and 305.2 Gg CO2e. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate technical and socio-political attributes that lead to the underperformance of two selected irrigation schemes (Shina and Bebeks) in the Lake Tana floodplains, Ethiopia. Irrigation application efficiency (AE) at nine experimental fields showed a wide range, from 20 to 80%, but was mostly between 40 and 60%. Irrigation water-use efficiency (IWUE) varied from 1.9 to 7.2 kg m−3 for onion and 0.9 to 1.2 kg m−3 for maize. The lined and earthen canal conveyance losses in Bebeks were 0.037 and 0.047 l s−1 m−1, whereas in Shina they were 0.033 and 0.044 l s−1 m−1, respectively. The overall consumed ratio (OCR) of water was 0.58 for Bebeks and varied from 0.73 to 1.2 in Shina. Both schemes are performing below the standard based on technical performance indicators. Irrigation water user associations (WUAs) were not implemented, but irrigation committees (ICs), composed of local political leaders, are managing both schemes. Canal and reservoir sedimentation from erosion of upstream catchment areas during the rainy season was the major problem. [ABSTRACT FROM AUTHOR]

Despite the growing popularity of culture-based fisheries (CBFs) associated with village irrigation systems (VISs) in Sri Lanka, there is less knowledge about factors that influence productivity levels. CBFs compete with rice for access to water in the VIS, so maximizing the efficiency of CBFs is essential to ensure that the limited water resources are used most effectively. To address this, primary data from 325 fish farming groups were used to estimate a stochastic translog production frontier. Technical efficiency in these irrigation systems was found to be generally low, and substantially lower than that of other aquaculture production systems in other Asian countries. This suggests that production can be increased substantially with better management using existing technology and resources. Removing subsidies, improving consultation with extension officials and improving water user rights – in particular, the introduction of a transferable community quota system – were found to be key means for improving efficiency. [ABSTRACT FROM AUTHOR]

Irrigation (‘blue’) water has high value as municipalities seek water security under growing populations and projected climates, but spatial variability makes estimating return flows to groundwater challenging. We demonstrate a framework for simulating spatially variable infiltration and derived distributions of return flows using an agricultural and vadose zone model to simulate recharge and nitrate leaching under irrigated corn in semi-arid northeastern Colorado, USA. Derived distributions indicated increased historical recharge (2-42%) as the spatial variability of applied irrigation increased. Projected climate in 2050 increased recharge above historical rates by up to 58%, but climatic effects decreased with increasing irrigation variability. [ABSTRACT FROM AUTHOR]

This article is a critique of the report of the committee chaired by Dr Mihir Shah on restructuring the Central Water Commission and Central Ground Water Board of India. It shows that the recommendations of the committee are not based on any sound understanding of the federal nature of water administration in India, water-sector performance or the problems confronting it. The ‘paradigm shift’ in the suggested approach to water management is based on flawed analysis of the performance of surface irrigation systems and outdated concepts of irrigation efficiency, and reflects the professional bias of its members against large water infrastructure and wishful thinking about what schemes like aquifer mapping can achieve. [ABSTRACT FROM PUBLISHER]

This article presents a method for analyzing the economic feasibility of modernizing irrigation systems. By using substitution relationships between two variables, one can determine irrigation performance and farm profit ​above which modernization would be justified from an economic point of view; ​and also the  investments and energy consumption up to which modernization could be considered cost-effective. By means of representative average values, this method is applied to the now widespread conversion from surface irrigation to drip irrigation in Spain. Two conclusions are drawn. First, modernization may, in some instances, be justified only if more productive crop patterns are implemented. Second, saving water is a cheaper option than using an alternative resource only under certain conditions. [ABSTRACT FROM PUBLISHER]

This paper explores the major determinants of heavy reliance on groundwater and the extent to which conjunctive use of ground and surface water affects the production efficiency of Pakistan’s irrigators. The results show that the major drivers of groundwater use in Pakistan’s agriculture are the variability and uncertainty associated with surface water delivery and that any effort to address the groundwater–energy nexus challenge should first consider fixing the problems associated with surface water supplies. The findings also suggest that having access to groundwater does not directly translate into improvements in technical efficiency of production. [ABSTRACT FROM PUBLISHER]

Gardeners can consume a large proportion of total domestic water, depending on their garden type and gardening style. We calculated water requirements of gardens based on species composition and land cover, and determined whether they can be predicted from the socio-economic, demographic and cultural characteristics of households. We recorded the plant species composition, garden cover types, and household characteristics of 258 households in suburbs of the Mediterranean coast of Catalonia. The distribution of the 635 species in these gardens were the input to a cluster analysis, in which semi-natural gardens, vegetable gardens, lawn gardens and ornamental gardens formed strong floristic groups, with ornamental gardens predicted to require the least water inputs and lawn gardens the most. We conclude that only income and a lack of work were related to our water requirement variable, reflecting the expense of water and the propensity of the retired to spend more time in the garden. [ABSTRACT FROM AUTHOR]

Deficit irrigation could be considered as one potential option to improve water productivity and obtain some level of assured income under water scarcity and drought conditions in Central Asia. This article investigates water productivity and economic returns to two varieties of potato crop under four different soil-moisture regimes in Uzbekistan. Results suggest that deficit irrigation may not be considered as an option to improve water productivity of potato crop, particularly when the deficit is high. However, deficit irrigation options could be still considered as a viable option to maintain food security and some assured farm income even under extreme drought conditions. [ABSTRACT FROM AUTHOR]

The thin-shallow-wet-dry irrigation (TIR) method is one of water-saving irrigation methods of rice cultivation. The effects of TIR method on water-use efficiency (WUE) of rice and soil microbial activities were investigated under three rates of nitrogen (N) compared to conventional flood irrigation. The TIR method decreased total water consumption (21.7–23.5%) and increased rice WUE (17.8–27.2%). At high N level, the TIR method significantly increased the number of nitrifying bacteria; the activities of catalase, invertase, and urease in soil at the jointing, booting, and milky stages; and the number of denitrifying bacteria at the milky stage. Increased N rate increased grain yield and water consumption simultaneously, and middle N level increased microbial biomass carbon (MBC) and N, the number of nitrifying and denitrifying bacteria, and the activities of catalase, urease, and invertase. Thus the TIR method at the middle N level can effectively improve rice WUE and soil MBC and enzyme activity. [ABSTRACT FROM PUBLISHER]

Irrigated agriculture makes an important contribution to the economy of Australia's Murray-Darling Basin. Competing water demand, recurring drought and climate change have ushered in an era of water policy reform. To recover water for the environment, surface water extraction is capped and investment in irrigation infrastructure is prioritized. This article applies a computable general equilibrium model to evaluate the economic impacts of investment in irrigation in a case study of the Murrumbidgee subcatchment. Results indicate an increase in regional output, income and employment, while at the national level there is a small negative impact resulting from the transfer of resources to the basin and the crowding out of private investment. [ABSTRACT FROM AUTHOR]

One option to deal with climate variability in agriculture is to build irrigation infrastructure, although this may lead to the overdevelopment of water resources, leading to ‘basin closure’. The Limarí Basin, in central north Chile, has relied on irrigation infrastructure over the last 30 years to increase water supply reliability and extend irrigated acreage, especially for permanent crops. This situation has reduced adaptation opportunities in the basin, which is currently experiencing a severe drought that, according to climate change projections, is expected to persist in the future, with important consequences for the sustainability of agriculture production. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Water Resources Journal / Revue Canadienne des Ressources Hydriques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Water Resources Journal / Revue Canadienne des Ressources Hydriques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

The use of water for irrigation is of concern to all those involved in water management in the Autonomous Community of Aragon. This article tackles issues that relate to the modernization of existing irrigation systems, by means of consolidation and improvement programmes, as the new priority of contemporary irrigation policy. At the same time, the article considers the roles played by the various agents charged with carrying out the programmes—basically state-owned companies—and of the farmers in their irrigation communities. The positive impact of these measures in achieving better and more efficient management of water resources, as well as the negative environmental impact that derives from the new demands for energy, are also presented and discussed. [ABSTRACT FROM AUTHOR]

Beginning in 1995, the Mexican Federal Government started a national program for promoting increase in agricultural productivity in the irrigation districts of Mexico. The program, Alianza para el Campo (Alliance for Agriculture) involves strategies for achieving the objective among which highlight a subprogram called Water Use Efficiency and Chemigation. The new law of rural development also includes actions towards the preservation of natural resources. The National Institute for Forestry Agricultural and Livestock Research of Mexico (INIFAP) is in charge of generate and transferring the research and technology in these programs as part o a national strategy to implement irrigation modules in several different ecological systems from the dry regions of North Mexico to tropical regions in the southwest. This paper describes the status and strategies for promoting irrigation efficiency in irrigation districts of Mexico. [ABSTRACT FROM AUTHOR]

Deep percolation loss of irrigation water is one of the main limitations in most agricultural soils of Saudi Arabia. Some synthetic polymers proved to be effective in mitigating this constraint. The present study was undertaken to investigate the changes in cumulative infiltration (D) and advance of the wetting front (Z) under ponded irrigation water using water-soluble polymers. Three different polyacryalmide (PAM) polymers, one nonionic (2J), and two anionic (21J and 40J) were used in this study at concentrations of 0, 10, 20, 30, 40, and 50 mg L to determine D and Z in a calcareous sandy soil (Typic Torripsamments). The results showed that for the three polymers at a given time, both D and Z decreased with increase in concentration. The decrease in D was slight, whereas that in Z was pronounced. The time required for Z to reach a given value was in the order 40J 21J 2J. This order is mainly attributed to the viscosity of the polymer solutions. The results also showed that the polymers at concentrations from 250 to 1000 mg L displayed non-Newtonian flow. The viscosity of 2J, 21J, and 40J at 250 mg L were 7.78, 10.56, and 9.90 mPa.s at a shear rate of 245 s1. Since these water-soluble polymers affect the wetting front mainly through their effects on viscosity, the potential of using them for soil erosion control is good, but their use for increasing water avail ability in the soil is not good. [ABSTRACT FROM AUTHOR]