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Water Conservation and Saving Technologies (WCSTs) can contribute to reduce the pressure on water resources from agricultural activities. A significant strand of literature on agricultural and innovation economics has explored the main drivers behind the adoption of WCSTs in agriculture, but due to the shortage of data most studies are based on survey analyses focusing on a specific case study. Therefore, results cannot be easily generalised. In this paper, we used a structured literature review (SRL) approach to systematise the original studies already published on the WCSTs adoption. Focusing on the econometric analysis used to estimate the main drivers of WCSTs adoption, our analysis started from an initial selection of 1027 studies, then after excluding book chapters, book, conference chapters and after checking abstracts and key-words we arrived to a final selection of 36 papers which have been deeply scrutinized with a structured analysis of their contents. Several findings have emerged from the analysis. The drivers of WCSTs adoption are various and heterogenous. We synthetized the main determinants into different categories: a) farm characteristics (land size, the presence of extension services, capital assets and internal organization within the farm; b) farmer characteristics (age, level of education, income); c) institutional environment (social networks, previous information on the technology, membership to farmer organizations, public fundings, access to credit, cost of water, access to groundwater, water constraint); d) geographic and climate characteristics (soil quality, drought, aridity). • The literature on WCSTs explored the main drivers of adoption but without generalisable results. • A structured literature review (SRL) has been used to systematise the studies already published on the WCSTs adoption. • This paper focuses on the econometric analysis used to estimate the main drivers or barriers of WCSTs adoption. • This analysis started from a base of 113 studies, the relevant studies have been reduced to 36 papers. • Various factors influence WCSTs adoption as farm, farmer, institutional, geographical and climatic characteristics. [ABSTRACT FROM AUTHOR]

Using Economic Irrigation Water Productivity (EIWP) as an indicator for on-farm irrigation decision-making is of utmost importance in addressing the challenges posed by poor policies in managing agricultural water use, particularly in water-scarce basins. Various modeling systems are available for quantifying crop actual evapotranspiration (ET a) and biomass needed for measuring the economic output obtained from each unit of irrigation water utilized. The difference in ET a and biomass estimates between the modeling systems could translate into a difference in EIWP outcomes, which influences the basin-wide irrigation water management. In this paper we examine the influence of selecting different ET a and biomass models, particularly the hybrid single-source energy balance HSEB, the Global Field-Scale Crop Yield and ET Mapper in Google Earth Engine GYMEE, and FAO's WaPOR V2, on evaluating EIWP on a basin-wide level. The method includes combining remote sensing and economic data to compare variability in ET a , biomass, and EIWP values derived from HSEB, GYMEE, and WaPOR. The approach is demonstrated with field survey data from the upper hydrologic unit of Lebanon's largest catchment, the Litani River Basin, in its three productive districts Baalbak, Zahleh, and West Bekaa for the year 2021. Field-scale mean monthly ET a and biomass estimates for all crops, obtained from both models, are very comparable. On a district level, the results reveal a reasonable model agreement for the four crops in the estimation of ET a with moderate to strong correlation (0.75 < r < 0.95). WaPOR consistently produces slightly higher mean ET a values for potato, wheat, and table grapes when compared to HSEB. Both models reasonably agree when estimating biomass for the four crops with high correlation (r > 0.9). Contrary to the ET a results, the GYMEE model consistently estimates slightly higher mean biomass values for all crops compared to WaPOR. The EIWP values produced by both models consistently indicate that potato holds the highest EIWP across all districts, followed by onion, table grapes, and wheat. The mean district HSEB-GYMEE model derived EIWPs are slightly higher than those derived from the WaPOR model for most crops. For EIWP obtained from HSEB-GYMEE, mean EIWP for potato is 12 times higher than that of wheat. As for that obtained from WaPOR, mean EIWP for potato is 10 times higher than that of wheat. The paper establishes a basis for future research on the application of remote sensing models in addressing water-stressed and socioeconomically challenged basins, with the potential to inform strategic irrigation management decisions based on model selection. ● WAPOR and HSEB models compared for ET and Economic Water Productivity. ● Model choice significantly impacts EIWP outcomes, affecting water management. ● Comparative analysis of ET and biomass enhances policy precision. ● Potato leads in EIWP across districts, optimizing water resource use. [ABSTRACT FROM AUTHOR]

• 390 major lineaments have been detected, mapped out and analysed in Kribi–Campo. • They are mostly oriented perpendicularly to the beach. • Their lengths range from 95 to 4910 m with an average of 1171 m. • They may affect inland intrusion of seawater in this coastal region. • For this, Landsat-8 image and geological data were used. This study detected, mapped and analysed lineaments from Landsat-8 satellite images of the coastal area of Kribi-Campo, Cameroon. Kribi, a fast-growing coastal city with a youthful population whose main industry is agriculture, is currently under great pressure due to the influx of internally displaced persons, victims of the current socio-political crisis in the western part of Cameroon. With the growing demand for food and water resources, it has been reported that saline soils and groundwater are affecting the agricultural productivity and domestic water supply of the area. This paper investigates the lineaments network in this area to understand its spatial distribution, its extent and the potential effect on inland intrusion of saline water. The datasets, including Landsat-8 imagery, geological data and a digital elevation model were processed using principal component analysis and filtering techniques. Linear features were enhanced based on textural changes of false colour composite images to describe fractures, faults and hydrology features. 390 effective lineaments were extracted automatically and manually from those images and analysed based on length, density and orientation using statistical analysis. But before this processing, non-effective lineaments that may correspond to terraces, linear valleys, cliffs, or tonal contrast as well as to human activities have been deleted. The effective lineaments range in length from 95 to 4910 m with an average of 1171 m. Although the lineaments are not isotropic, their perpendicular orientations to the coast suggest potential intrusion of saline water into regional groundwater resources and farmlands. The paper presents a combined technique of geospatial and statistical analysis in the interpretation of lineament effects which have the potential to inform on salinity intrusion in coastlands. The electrical conductivity of 50 groundwater samples collected in the study area are used to validate the impact of lineaments on seawater intrusion. [ABSTRACT FROM AUTHOR]

Abstract This paper introduces a technique of water management by managing water abstraction along a branch canal. The selected study area is Awlad Sakr District, Sharkia Governorate, Egypt and the selected canal is Dafan canal. The paper introduces suitable tools to reduce the gap between demand and supply by managing water abstraction along the branch canals. Different approaches of storage water are applied during this research in order to overcome the shortage of water at the end of the main canal and its branches. The results of this study are summarized that SOBEK program is a good tool to estimate the hydraulic characteristics in open channel under different scenarios. Another result is that Awlad Sakr District, Sharkia Governorate, Egypt is an example of farmers depending on drainage water in agricultural irrigation. For management, it is found that case 16.7% storage is the best, for 25% storage the banks in some location needed to be raise, while 33.3% has shortage of water in some locations along the canal, which means that controlling water abstraction can manage the water shortage. [ABSTRACT FROM AUTHOR]

Abstract Optimization allocation of agricultural water and land is a very complex system involves multiple objectives. Moreover, weights of each objective were signed by subjective judgement of decision makers is unreasonable. Furthermore, uncertainties are inevitable in the optimization allocation of irrigation water and land. In order to solve the above problems, this paper developed an improved multi-objective stochastic fuzzy programming method. The developed model was then applied to a case study in Wuwei City, Gansu Province, China. Maximum net benefit, maximum agricultural water productivity, and minimum irrigation area were regarded as planning objectives. A series of optimal irrigation and planting structure schemes were obtained under multiple uncertainties. From the results, water resources shortage in Wuwei city is very severely and it could not satisfy Wuwei's water demand even if the risk probability P i reaches 0.25. Moreover, water and irrigation area would vary in different crops. Such changes would mainly take place in potato, vegetable and cucurbit, which have the same characteristics with higher yield, lower cost or lower irrigation quota than other crops. Furthermore, the decision makers could make reasonable decisions on the optimal use of irrigation water and land resources under multiple objective and uncertainties based on the obtained results. Highlights • This paper developed an improved multi-objective stochastic fuzzy programming method. • It simultaneously optimizes irrigation water amount and irrigation areas. • AHP method was introduced to assign weight of each objective. • Optimal irrigation schemes were obtained under multiple uncertainties. • It could be helpful to make decision under multiple uncertainty and multiple objectives. [ABSTRACT FROM AUTHOR]

• This paper proposes an Indexed Meta-Goal Planning Model to solve imprecision in data. • This integrated model is a novelty and has been applied to sustainable optimal cropping patterns. • It has been tested in Iran to solve conflicting uses of natural resources. • The results compared with Sen and Pal show no variation in land allocation for each crop. • the least variation in all problems is for wheat and barley production. Meta-Goal Programming (MGP) is a simultaneous cognitive evaluation of the degree of achievements for original decision goals considered in a GP model. However, in most real-world situations, environmental coefficients and related parameters are not easily available. In such a situation, the decision-maker must consider various conflicting targets in a framework of uncertain aspiration levels at the same time. On the other side, Interval Programming (IP) is a method used to increase the range of available decision-maker preference structures in GP. In the perspective of solving the conflicts between agriculture and water use towards sustainability, this paper proposes an Interval Meta-Goal Programming Model (IMGPM) dealing with imprecision in data that covers interval coefficients, target intervals, and interval bounds of meta-goals. This novel methodology has been tested in a study area in Iran to validate its added value in solving conflicting uses of natural resources by economic sectors. This integration together with its application for sustainable optimal cropping patterns (agroecosystem planning) represents a novelty in the field of ecological modeling. The management solutions of our method in terms of land allocation are different from those in Sen and Pal (2013) model. In the case of Iran, many socio-ecological-economic strategies and policies should be necessary for improving the agricultural sector. More specifically, on the basis of rainfall amounts and spatial patterns, this approach can represent a decision-support system able to define strategies for additional water storage useful to support crop production. Furthermore, the availability of water together with the sustainable use of fertilizers can mitigate the risk of land degradation, guaranteeing people employment, food security, and economic profits. Although the present methodology seems to solve the problem of multi-goals decision-making, the inclusion of spatial relationships is able to introduce dependencies between the management of land use in adjacent areas, making the present approach nearer to real-world functioning. [Display omitted] [ABSTRACT FROM AUTHOR]

The majority of people in Sub-Saharan Africa (SSA) live in rural communities and practice subsistence farming. Variations in climate and other environmental factors affect the stability of local food production. This instability makes the adoption of efficient farming techniques critical in helping farmers achieve food, income, and livelihood security. Agricultural water conservation techniques called water harvesting are being implemented to increase crop yields in SSA. These techniques have been shown to increase water productivity, nutrients, and organic matter in the soil. This paper uses high-resolution imagery to identify and differentiate between farms using conventional and water-harvesting farm methods. An ordinary least-squares regression model was used to correlate seasonal maximum normalized difference vegetation index (NDVI) values with environmental factors for the different farming methods. The results suggest that water harvesting farm techniques have higher crop yields and are less dependent on precipitation than conventional farming methods. The methodology presented in this paper can be used to map use of water harvesting over large areas and monitor associated differences in productivity. [ABSTRACT FROM AUTHOR]

Snow depth is an essential climate variable (ECV) in hydrologic cycle and is widely used for policy-making in agriculture and water resource management. Regional and global snow depth data also provide useful information for the study of climate change. In this paper, two new methods for snow depth estimation are proposed, which are based on combination of pseudorange measurements recorded by GNSS (Global Navigation Satellite System) geodetic receivers. The first one is the linear combination of pseudorange measurements of GNSS dual-frequency signals, which is geometry-free i.e. free of the effect of geometry between satellite and receiver. The second one is the linear combination of pseudorange measurements of GNSS triple-frequency signals, which is free of effects of both geometry and ionospheric delays. Both pseudorange combination methods do not rely on cycle slip detection and repair, which are required by carrier phase combination methods. Theoretical models are developed to describe the relationship between the spectral peak frequency of the combined multipath series and the antenna height. Two experimental datasets collected by UNAVCO community are employed to validate the proposed methods. The results demonstrate that there exists good agreement between the proposed methods and field observations of snow depth and the RMSE of the proposed methods are less than 3.2 cm at first experimental station. In addition, there is good consistency and similarity in snow depth estimation among the proposed method, SNR method and dual-frequency carrier phase and pseudorange combination method. [ABSTRACT FROM AUTHOR]

Conservation agriculture (CA) is shimmering up as a potential solution to food security, biodiversity, mitigating climate change effects on agriculture and water scarcity challenges. Adoption of CA found to be related not only ecological factors, but also depends on the characteristics of the adopter, their level of perception and the decision-making process. This paper examines the interactions and inter-relationship among climate change perception, energy perception, and level of knowledge on CA as dependent variables with a set of operating agro-economic, social-ecological, communication variables from new alluvial zone of West Bengal. Total of 65 farm households are surveyed using non-random snowballing sampling method. From the study it has found that farmers' perception on energy, climate change perception, and knowledge on CA are interwoven with each other. As the farmers of the study region are in initial stage of adoption they need access to proper CA-related information and Upgradation of functional education through training, workshops, or demonstrations. Here are the points of interventions for successful on-farm adoption of CA. While land fragmentation and fuel cost are came up as two important predictors. • Successful adoption of conservation agriculture depends on the interaction between farm social-ecological factors. • Farmer's own perception drives adoption of conservation agriculture. • Optimization of irrigation and number of ploughing are two pre-requisites. • Access to proper information is important in knowledge stage of innovation-decision. [ABSTRACT FROM AUTHOR]

Achieving water security has emerged as a major objective in Africa, yet an analytical or diagnostic framework for assessing water security in African countries is not known to exist. This paper applies one key dimension of the 2016 Asian Development Bank's (ADB) Asian Water Development Outlook (AWDO) to assess levels of water security for productive economies in countries of the Southern African Development Community (SADC). Economic aspects of water security cover four areas: economic activities in the broad sense, agriculture, electricity, and industry. Water security in each area is measured through application of a set of indicators; results of indicator application are then aggregated to determine economic water security at a country-level. Results show that economic water security in SADC is greatest in the Seychelles and South Africa, and lowest in Madagascar and Malawi. Opportunities for strengthening economic water security in the majority of SADC countries exist through improving agricultural water productivity, strengthening resilience, and expanding sustainable electricity generation. More profoundly, this paper suggests that there is clear potential and utility in applying approaches used elsewhere to assess economic water security in southern Africa. [ABSTRACT FROM AUTHOR]

Water price reform is an effective way of rationalizing and protecting water resources in areas where water is scarce. This paper first presents a method for measuring water footprint by sector based on the non-competitive input-output technique. Second, this research explores the relationship between water price adjustment and labor compensation, as well as regional water export. Accordingly, this paper constructs a mathematical planning model for differentiated water price adjustment by sector with the objectives of minimum water exports and maximum labor rewards, and conducts a simulation study in the water-scarce Henan Province. The study's findings suggest that: (1) In contrast to direct water use, water consumption in Henan Province is more balanced in terms of water footprint, with the food and tobacco processing industry replacing agriculture as the leading water consumption sector. (2) Sectoral differentiated pricing saves 6.9% more export water resources in Henan Province than uniform sector-wide pricing with the same export GDP loss. (3) At present, the industries in Henan Province that are in urgent need of increased water charges are agriculture, textile industry, Manufacture of leather, Processing of timber and furniture, Manufacture of paper and printing, and Manufacture of chemical products these totals 6 industries. An increase of $1.73, $4.87, $38.55, $51.20, $5.83 and $6.55 per cubic meter in the water price of these six industries can reduce the export water resources of Henan Province by 10.72%. As a result, our findings can be used to optimize water allocation and improve sustainable water use in water-scarce regions. • Sub-sectoral differentiated water price adjustment method is proposed. • Sectoral differentiated pricing approach is more conducive to water conservation. • The method can find the local sectors in urgent need of water price adjustment. • Adjust sectoral water price with minimize economic impact to achieve water saving. [ABSTRACT FROM AUTHOR]

Plastic mulch films are widely used in agriculture to enhance crop production by suppressing weeds, conserving soil water and increasing soil temperature. The majority of plastic mulch films are however not biodegradable and are typically removed after each growing season. Recovery of these plastics from the soil is difficult and can affect successive crop yields while causing substantive cost to the environment and farmers. Due to increasingly stringent regulations regarding use of non-degradable plastic in agriculture they are likely to be phased out in the near future. In the past 10 years several classes of ‘biodegradable’ materials have been studied but most of these films are reported to be relatively weak in mechanical properties, not efficiently degradable and cost prohibitive. More recently, researchers have turned their attention to sprayable biodegradable polymer coatings for use on soils due to their easy application and versatility. The ability to mix natural additives, plasticizers and fillers to control and improve the mechanical and biodegradation properties of the core polymeric mulch film has been the driving force behind the development of these next generation sprayable polymeric mulch films. There have been many excellent review articles and papers written about polymeric mulch film, but the developing sprayable polymer systems have not been reviewed to the same extent. This paper focusses on the research progress in the area of biodegradable and sprayable polymer mulch film with emphasis on polymer formulations, properties and application. It also discusses current research to highlight the importance, potential benefits and future challenges in developing a cost effective biodegradable sprayable film for use in production agriculture. [ABSTRACT FROM AUTHOR]

Global Warming will probably modify air circulation patterns and increase the severity of droughts, heat waves, heavy precipitation, and floods across the world. A device called 'aerological accelerator' (AeAc) is proposed in this paper to harvest water from the air using a very high tower where the warm and humid air enters from the bottom and rises till the top driven by buoyancy force. This AeAc device is similar in operation principle to a solar chimney power plant (SCPP) with additional features. A mathematical model was developed to calculate the potential energy and water that can be generated in various environments. The calculation results show that clouds are generated within and out of the chimney and the latent heat released by the vapor can noticeably increase the power output of the modified SCPP. With a proper water collecting method, the system can supply water and carbon-free renewable energy for residential and agricultural use. The present study opens the perspective that with minor improvements, significant energy and freshwater production might be possible using these tall engineering structures, whose high chimney can be built thanks to fabric balloons filled with gases lighter than air. • A device called 'aerological accelerator' (AeAc) is proposed to gain water. • Clouds are generated within and out of the chimney. • Water generation under various environment has been analyzed. • The system can supply water for residential and agricultural use. [ABSTRACT FROM AUTHOR]

• Impacts of agricultural water management on hydrology and environment were studied. • Sixty year's data on irrigation, drainage, soil salinity, groundwater etc., were analyzed. • Uncontrolled irrigation and the lack of effective drainage had several negative effects. • Water-saving practices benefit salinity control but do harm to wetland protection. • A balance between several factors is required for effective water management. Irrigation projects often result in many far-reaching environmental changes. This paper considers the case of the Hetao Irrigation District, the largest irrigation project along the Yellow River in China, and studies the impacts of agricultural water management on the hydrology and the environment. Long-term data (1954–2013) concerning irrigation, drainage, soil salinity, groundwater, and the environment of Wuliangsuhai Wetland, the lake that receives the drainage water, were collected and analyzed. The findings show that uncontrolled irrigation and the absence of effective drainage initially resulted in a rising groundwater table, worsening soil salinization, and the expansion of the lake, which is an important internationally recognized wetland. The completion of an artificial drainage system and the implementation of water-saving practices have had promising effects on lowering the groundwater table and controlling soil salinity. However, the risk of soil salinity is still threatening the irrigation system because salt is continuously accumulating within it and the total dissolved salts (TDS) in the groundwater are increasing. For better soil salinity control, more effective drainage is necessary to drain more salt and lower the water table, but this may harm the natural vegetation and the eco-environment of the Wuliangsuhai Lake because the non-point-source pollution from agricultural drainage has resulted in a serious eco-crisis in the Wuliangsuhai Lake. The results show that it is important to ensure there is a certain amount of low-TDS drainage water to protect the Wuliangsuhai Lake environment. Therefore, a balance must be achieved among soil salinity control, groundwater quality, favorable conditions for natural vegetation, and wetland protection. Further research is needed to develop optimal agricultural water management strategies, especially in the context of the ongoing water-saving renovation program. [ABSTRACT FROM AUTHOR]

From the perspective of sustainable development in irrigation areas, imperfect constraints, which have negatively impacted previous agricultural planting structure optimization models, tend to produce unreasonable optimization results. Thus, in this paper, attempts are made to incorporate the resilience of water resource systems into the constraint set and explore the optimal layout of agricultural planting structures in irrigation areas. We selected 12 sample irrigation areas in Heilongjiang Province, China, including Chahayang, Fuyu, and Tailai, as the research areas and considered their actual situations. Then, we established a multiobjective optimization model for an agricultural planting structure with rice, soybean, and corn planting areas as decision variables; socioeconomic benefits, agricultural production benefits, ecological benefits, and water resource benefits as objective functions; and water resource system resilience and net crop output value and other factors as constraints. Fifteen scenarios were assessed through the combination of objective functions, and the nondominated sorting genetic algorithm III (NSGA-III) was used to optimize and analyze the agricultural planting structure of typical irrigation areas in Heilongjiang Province and to determine the optimal planting plan. The research results found that the function values adjusted by planting area have significantly improved compared to those before optimization. The adjustment trend of agricultural planting area is to increase the planting area of rice and soybean and reduce the planting area of corn. The introduction of constraints on water resource system resilience ensures that other benefits remain basically unchanged; thus, the water resource objective function is significantly better with resilience constraints than without them. Therefore, water resource system resilience can act as an effective constraint; this finding enriches and expands the theoretical and methodological system for optimizing the management of agricultural planting structures in irrigation areas and thus provides important technological support for ensuring regional food security, ecological security, and water security, which has substantial practical significance. • Exploring the feasibility and implementation path of embedding the resilience of water resource systems. • Seeking the optimal adjustment plan for agricultural planting structure in irrigation areas based on the NSGA-III algorithm. • Analyzing the constraint effect of water resource system resilience on the optimization of agricultural planting structure. [ABSTRACT FROM AUTHOR]

The increasing pressures of global warming, population growth and epidemic occurrence are causing challenges in meeting the growing requirements for water, energy and food. In particular, the contradiction between the supply and demand for water, food, and energy is exacerbated by inefficient resource utilization and carbon emission increase. Incorporation of the interlinked aspects of water, energy, food and carbon emissions from agricultural systems into one water-food-energy-carbon nexus facilitates integrated resource management. Biochar application to farmland is a potential strategy for carbon management and agricultural productivity improvement. The integration of biochar systems and the water-food-energy-carbon nexus is an efficient and coordinated alternative method for sustainable agricultural management and a crucial strategy for addressing water, energy and food security issues. Accordingly, this paper proposes an approach for the synergistic regulation of water, land, energy, and carbon emissions in a circular agricultural system by balancing water supply and demand, land allocation, electricity consumption, and economic upgrading principles. A two-stage circular agriculture framework is constructed, with biochar and electricity generated from agricultural residues at the first stage and employed at the second stage. Economic-environmental-energy harmonization is considered in the methodology, and the agrotechnical potential of biochar is quantified via crop yield increase and greenhouse gas emission reduction functions. This approach can assist decision makers in providing the best policy options given certain agricultural resources to achieve the maximum economic performance of the system while minimizing environmental side effects. In this paper, the model framework is applied to the Sanjiang Plain in northeastern China to verify the feasibility of the approach. The results indicate that the external electricity demand is reduced by 87.8% due to the generation of biofuels. Cropland greenhouse gas emissions are reduced by 34.09%–67.06% via the application of biochar. This study proposes an optimization method with important implications for the improvement of regional cropland management techniques and development of sustainable circular agriculture. This methodology can be extended to other agriculture-centered regions with limited resources and environmental problems. • Carbon cycle is integrated in agricultural water-food-energy-carbon (AWFEC) nexus. • An AWFEC nexus based model is developed for agricultural resources recycling. • Biochar and electricity are optimized sustainably for circular agriculture. • Analysis of resources recycling on economic-environmental balance is performed. [ABSTRACT FROM AUTHOR]

China's Yellow River Basin (YRB) has large watershed but scarce water resources. More importantly, most parts of the YRB are located in semi-arid areas of Northwest China, where the ecology and environments are fragile. So, ecological restoration and agricultural production always are the key research topics of the YRB. However, the specific research interest of YRB changed over time and was always closely related to the implementation of government policies. Hence, we conducted a comprehensive analysis of YRB's research topics based on the methods of bibliometrics. The results showed that the number of papers about YRB's research experienced a change from slowly increasing (1998–2010, 83 papers) to rapidly increasing (2011–2015, 128 papers), and then to exponentially rising (2016–2020, 369 papers). Secondly, the main research fields of the YRB included farming, crops, water, soil, environment, and etc. The journal of Agriculture Water Management had the highest global total citations and H-index, even local cited references were the highest among all of the reference papers about the YRB. Through summarizing the most cited papers and references, we found the most important research hotspots about the YRB were: the impacts of climate change and human activities on the amount of sediment in the YRB, the management of soil erosion and vegetation restoration in the YRB, and the relationship between crops and environment and management in the Loess Plateau of China. In addition, " Loess Plateau " was the most frequent keyword in the past ten years and the popularity of " climate change " rose sharply in the past five years. For YRB's research in near future, how to effectively control carbon emissions, greenhouse gas (GHG) emissions, and carbon surplus is becoming an important implication for YRB's agricultural production and ecological restoration in the future. In general, this research is expected to promote a comprehensive and quantitative understanding of the past, present and future of YRB's research. • The research of Yellow River Basin (YRB) has exponentially increase in 2016–2020. • The research interest was closely related to the implementation of government policies. • The main research fields of the YRB included farming, crops, water, soil, environment. • The keyword of "Loess Plateau" was the most frequent keyword in the past ten years. • The carbon emissions, and carbon surplus is becoming an important research direction for YRB. [ABSTRACT FROM AUTHOR]

Abstract: Economic analysis of climate scenarios and alternative water policies is critical for development and implementation of appropriate water policies and programs. Mathematical models have been developed to assess water resources policies due to their ability to explicitly represent the biophysical dynamics of natural systems while integrating these within social and economic constraints. These models have been criticised, however, due to the problems of simplification, overspecialisation, plausibility and lack of empirical validation. This paper introduces a mathematical programming model which uses positive mathematical programming method to calibrate and model agriculture and water use in the Murray-Darling Basin of Australia. This paper reviews the theoretical and technical details of the model development including the key steps taken in collating and scaling the biophysical and economic data, and to address model parameterisation issues. The paper summarises results of an application of the model for assessing climate change impacts in the form of reduced rainfall and water allocations and increased crop water use for agricultural production. The results show the degree of variability in gross values under different climate scenarios compared to the base case scenario, especially in very dry years. The results also show how on-farm adaptation options and water markets can mitigate these losses. [Copyright &y& Elsevier]

Abstract: Irrigation plays an increasing important role in agriculture of China. The assessment of water resources utilization during agricultural production process will contribute to improving agricultural water management practices for the irrigation districts. The water footprint provides a new approach to assessing the agricultural water utilization. The present paper put forward a modified calculation method to quantify the water footprint of crop. On this basis, this paper calculated the water footprint of major crop in Hetao irrigation district, China. Then, it evaluated the influencing factors that caused the variability of crop water footprint during the study period. Results showed that: 1) the annual average water footprint of integrated-crop production in Hetao irrigation district was 3.91m3 kg−1 (90.91% blue water and 9.09% green water). The crop production in the Hetao irrigation district mainly relies on blue water; 2) under the integrated influences of interannual climate variability and variation of agricultural inputs, the water footprint of integrated-crop production displayed a decreasing trend; 3) the contribution rate of the climatic factors to the variation of water footprint was only −6.90%, while the total contribution rate of the agricultural inputs factors was −84.31%. The results suggest that the water footprint of crop mainly depends on agricultural management rather than the regional climate and its variation. The results indicated that the water footprint of a crop could be controlled at a reasonable level by better management of all agricultural inputs and the improvement of water use efficiency in agriculture. [Copyright &y& Elsevier]

Abstract: This paper describes the development of Bayesian networks for evaluating the trade-offs between water utilization for agriculture in Shandong irrigation district and the ecosystems in the Yellow River Estuary. The framework of the Bayesian networks includes four parts: the recommended environmental flow represents the reasonable amounts of water for the ecosystem; water inflow is the natural hydrological process which can be monitored by hydrological stations; the economic analysis evaluates the economic losses after water transfers from agriculture to ecosystem and the acceptability of economic compromise by irrigation stakeholders; the ecological analysis calculates the alteration of the river sediment and water salinity after different environmental flows were maintained. Nine actions were investigated which represented the combinations of different water inflow levels and environmental flows security levels. The probability for the economic and the ecological aspects change regularly under different water inflow levels. The average economic acceptable indices were 58.2%, 55.5% and 51.3%, which showed a downward trend with decreasing levels of flow; while for the ecological aspect, it is the upward trend. At the higher environmental flow maintenance level, the economic losses become harder to accept by the irrigation stakeholders, while the ecosystem can be maintained in a better situation. Under the current water resource management system, there is not an action that can fulfill the economic and ecological needs at the same time. The Bayesian networks presented in this paper can assist catchment managers in making more informed decision to manage their water resources. [Copyright &y& Elsevier]

A water price increase has been used as an effective method to guarantee national water security and maintain national food security in China. The reasonableness of the water price has a direct influence on people's attitude, behavioural decision regarding willingness to pay, and motivation for water conservation. A double-bounded dichotomous choice contingent valuation method was used to assess the impact of integrated agricultural water price reform on farmers' willingness to pay for irrigation water in northwest China. The estimated mean willingness to pay in the study area was 0.144 RMB/m3. A comparison showed that higher education and longer experience in farming were likely to result in a higher willingness to pay in the study area. Participants who had a higher awareness of water price reform showed a higher likelihood of agreeing to higher bidding. Those who thought the current water price was lower had a higher willingness to pay for irrigation water. Participants who considered agricultural water resources to be scarce in the area also had a higher willingness to pay. In contrast, the bidding variables were negative and significant at the 1% level, showing that participants were more inclined to reject a higher bid. Meanwhile, the older the participant, the less they were willing to pay. An unintended finding was that participants' willingness to pay decreased if they chose to use water-saving technology. One possible explanation was that the investment in the construction of the infrastructure (such as pipes and pumps) may have exacerbated farmers' burden and may not have resulted in any benefits to them. Based on the results of this paper, a related optimization policy was presented for water price reform. Image 1 • Water price reform influenced farmers' bearing capacity. • Willingness to pay was higher than the prices currently paid in northwest China. • Six variables were positively while three ones were negatively significant on WTP. • A reasonable grasp of the scale of the water price adjustment was essential. [ABSTRACT FROM AUTHOR]

• The effect of wind has been taken into account in analyzing the dispersivity. • The method of asymptotic analysis is adopted to study the dispersivity. • The effect of ecological degradation has been taken into account. • The critical length and duration of the influenced region has been illustrated. The effect of global climate change is increasing and it can influence agriculture in many ways, especially in that it makes great threaten on agricultural water resources. Since agricultural water supply is a key issue for agricultural production, indicators for contaminant transport in wetlands should be considered in order to solve agricultural water pollution and promote water protection. In this paper, we analyze the environmental dispersion in a typical three-layer wetland flows with the effect of wind taken into account. The analytical solution for velocity distribution is rigorously derived and the dependence of characteristic parameters on averaged dimensionless velocity is recorded. The asymptotic analysis theory of Gill is employed to measure dispersivity for natural wetland flows with a commonly high Peclet number. Both velocity and environmental dispersion are significantly influenced by wind, in terms of its direction and the magnitude of force. The effects of hydraulics and ecological degradation are considered to obtain the analytical solution for the mean concentration and maximal critical length of the region influenced by the process of contaminant transport. [ABSTRACT FROM AUTHOR]

The energy, water and food (EWF) nexus modelling and analysis frameworks proposed recently have demonstrated their effectiveness in the assessment and quantification of synergies and trade-offs in the interlinkages between the three sectors. They largely rely on static, deterministic or equilibrium-based models that facilitate in making decisions for well-behaved and predictable resource systems over time. These frameworks, however, are partly limited in their functionality due to the fact that they do not consider the exposure of systems to the dynamic nature of extrinsic uncertainties and the associated risks in the nexus. Hence, there is a need for a sequential learning, planning and optimal control modelling framework which could help achieve adaptive systems under volatile conditions with the objective to maximise economic output and enhance their operational resilience. In this paper, the authors discuss the development of a novel computational framework which incorporates "algorithmic resilience thinking" to achieve adaptive and robust inter-networked systems. Here, the question of adaptive systems for EWF nexus resilience is posed as a reinforcement learning problem based on sequential decision-making called the Markov decision process (MDP). The authors further discuss a case study, considering weather volatility, its spatial impact on vegetation, and the consequent risks on the water-food nexus for outdoor agricultural operations in the State of Qatar. The application of the developed framework particularly demonstrates promise in providing the functionality to track and mitigate emerging risks that have the potential to cause unprecedented disruption in the operations of integrated natural resource systems. The outcome of this study has positive implications for the advancement and effectiveness of EWF nexus planning and risk management to avert resource shortages and price risks, socio-economic disruption, and cascading failures of critical infrastructures, particularly when the global supply chains are subjected to stresses and shocks, such as extreme weather conditions. • A flexible computational framework is proposed to model the interactions between the energy, water and food (EWF) sectors. • Advanced techniques in computational intelligence are utilised for the mathematical representation of EWF resource systems. • An iterative algorithm tracks emerging risks in the EWF nexus, and aids in optimal decision-making for risk mitigation. • A case study considers the impact of weather volatility on outdoor agricultural operations in the State of Qatar. [ABSTRACT FROM AUTHOR]

• A model is presented to minimize the amount of water consumed by the energy sector. • The model dispatches the generation-cooling mix to quantify water consumption. • Electricity demand in California needs a minimum of 58,673 cubic meters of water. • 16% reduction in the California electricity usage cuts the water consumption by 94%. • No hydro generation in California reduces water consumption by 61%. Water is the greatest resource for life on earth. Various human activities affect the quality and quantity of this precious resource, and there are many initiatives to ensure water resources are protected from overuse, pollution, and industrial and agricultural waste. Since the energy sector is the second largest consumer of water after agriculture, water and energy systems are highly interlinked. Specifically, a significant amount of water is used in the energy generation process primarily for producing steam and for cooling processes, the water used for cooling processes will be returned back to the reservoir. Consequently, most fossil-based power plants in addition to consuming water, impact the water resources by raising the temperature of water withdrawn for cooling. Limited water resources can also affect the ability to generate electric power to meet the demand. Therefore, integrated planning for the interleaved energy and water sectors is essential for both water and energy savings. This paper describes a comprehensive study that analyzes and quantifies water withdrawals and consumption of various electricity generation sources such as coal, natural gas and renewable sources. The study has developed a general model to determine the water consumption and impact for various energy generation scenarios and to minimize the amount of water consumption while considering several limitations and restrictions. A case study performed for the state of California indicates that quantification of water consumption can be formulated and potential opportunities for water saving can be identified. [ABSTRACT FROM AUTHOR]

Highlights • A socioeconomic-biophysical framework of agricultural water management systems. • Six stages of development are identified: human's early water use to the present. • Historical information demonstrates the complexity of systems and their impacts. • Understanding the interconnectedness of the system's influencing factors is critical. • Policies must consider both positive and negative impacts of systems' development. Abstract While the earliest irrigation societies were relatively simple in their technical and social structures, they represent complex socioecological systems where human activities interact with the biophysical environment. Actions taken within any part of the system affect other parts, often with detrimental environmental impact. In this paper, we propose an integrated framework that explains how the socioeconomic and biophysical factors influence the development of agricultural water management (AWM). We categorize AWM developments into six distinct stages with increasingly complex interactions between the socioeconomic and biophysical components of the system. We argue that the failure of AWM developments across time and space, and within any stage of complexity, is a consequence of a lack of understanding of the interconnectedness within these complex systems and a lack of political will to acknowledge and investigate the failure, which allows both positive and negative effects to influence decision-making. [ABSTRACT FROM AUTHOR]

Abstract Agricultural water and land, which are intricately related, are the two most critical resources for food production. However, the sustainability of agricultural water and land resources is faced with challenges due to intensive human activities and climate change. This paper builds crop water footprint model under uncertainty, and evaluates regional crop (rice, maize and soybean) blue and green waterfootprint under different probability. On this basis, the water footprint characteristics and differences of crops were analyzed. Then, an optimization model of crop planting structure with the objectives of minimum blue water footprint and the maximum agricultural net benefit was constructed and Monte Carlo simulation method was used to solve the model. The model can take into account the crop water footprint at different probabilities, enabling decision makers to combine years of information to make better decisions. Then, the model was applied to the Hulan River Irrigation District, and three scenarios were designed to analyze the optimal planting structure under different conditions. Under different scenarios, the optimization results have certain differences, but overall, increasing the area of crop cultivation, especially rice, has a good role in promoting regional agricultural development. Due to the optimization of the planting structure, the net benefit of the irrigation area increased by 7%, 15% and 5% in each of the three scenarios. Solutions are valuable for producing scientific alternatives that help decision makers determine the water and soil relationship management policies they need. [ABSTRACT FROM AUTHOR]

Highlights • Most water conservation policies will target agriculture. • Farmers will adapt, affecting agricultural outputs and propagating the shock economy-wide. • This will in turn affect commodity prices and irrigators will reassess their choices. • Modeling water rationing impacts needs to account for two-way micro-macro feedbacks. • To this end, we develop an iterative coupling between a micro and a macro model. • The iterative coupling presents non-trivial differences compared to conventional modeling approaches. Abstract Most water conservation policies will target agriculture, the largest human consumptive use and that concentrating the marginal (i.e. least productive) uses of the resource. Adaptation to irrigation rationing policies at the micro level will have an impact on agricultural outputs and propagate to the rest of the economic sectors at a regional and supra-regional (macro) scale. As the economy transitions towards new equilibrium commodity prices, the relevant prices for agriculture will change and this will in turn affect irrigators' decisions. This paper proposes an iterative coupling between a decentralized, non-parametric Positive Multi-Attribute Utility Programming representation of irrigators and a regionally-calibrated Computable General Equilibrium model to assess interlinkages (i.e. two-way feedbacks) between the micro- and macro-economy. Results from an application to irrigation water charges in the Murcia Region in Spain show that the coupled micro–macro model yields lower abatement costs as compared to the stand-alone micro model. [ABSTRACT FROM AUTHOR]

Abstract: A fertile discussion is developing in the EU regarding the application of the Water Framework Directive (60/2000) (WFD), the legislative act that provides the framework for water regulation in Europe and emphasises the role of economic instruments in water policy. The objective of this paper is to provide an evaluation of different instruments designed to deal with the management of water for agriculture, in the perspective of WFD implementation and agricultural price scenarios. The paper focuses on the regulation of mixed source unmetered water and carries out a comparison of flat rate versus differentiated contracts as the policy instrument. The analysis is based on a combination of linear programming and a Principal-Agent model. The empirical model is applied in an agricultural area of Northern Italy. The results show the feasibility of incentive-oriented policy instruments, even in the less sophisticated form of flat rate area payments. They also show the relevance of agricultural market scenarios and policy scenarios in the design of the optimal policy instruments. The adoption of such instruments, however, could require a revision of the role of different institutions involved in water management. [Copyright &y& Elsevier]

Abstract: Water resources use in agriculture is generally quantified in relation to the harvest. In contrast, this paper takes a consumer perspective by assessing water use in relation to the final consumer product. The paper analyses the water use related to two products that are typical to Italian consumers: pasta and pizza margherita. We use the water footprint concept as a tool to quantify and localise this water use. The water footprint of a product is the volume of freshwater used to produce the product, measured over the various steps of the production chain. We find that the water footprint of dry pasta made in Italy amounts to 1924l of water per kilogram of pasta. The water footprint of a 725g pizza margherita is 1216l of water. The impacts of the water footprints of pasta and pizza depend on the vulnerability of the water systems where the footprints are located. The impact of the water footprint of pasta is most severe in Puglia and Sicily, where groundwater overexploitation for durum wheat irrigation is common. The impact of the water footprint of pizza is more diverse. It is concentrated in the first step of the supply chain of tomato puree and mozzarella, i.e. in the cultivation of tomatoes and the feed crops of dairy cows. The bread wheat used for the pizza base does not have large impacts. The water footprint impact of the tomato puree on the pizza is concentrated in Puglia (groundwater overexploitation and pollution related to tomato cultivation) and Emilia-Romagna (water pollution). The water footprint impact of mozzarella lies mostly in the effects of water use for producing the feed ingredients for the dairy cows. Mozzarella production further poses a potential threat to water quality, mostly in the Po valley, but this problem seems to be properly regulated, although possibly not fully controlled. [Copyright &y& Elsevier]

Abstract: Experiences from the Mitigation Options for Phosphorus and Sediment (MOPS) projects, which aim to determine the effectiveness of measures to reduce pollutant loading from agricultural land to surface waters, have been used to contribute to the findings of a recent paper (, Agricultural Systems, 99, 67–75), which reviewed the efficacy of contemporary agricultural stewardship measures for ameliorating the water pollution problems of key concern to the UK water industry. MOPS1 is a recently completed 3-year research project on three different soil types in the UK, which focused on mitigation options for winter cereals. MOPS1 demonstrated that tramlines can be the major pathway for sediment and nutrient transfer from arable hillslopes, and that although minimum tillage, crop residue incorporation, contour cultivation, and beetle banks also have potential to be cost-effective mitigation options, tramline management is the one of the most promising treatments for mitigating diffuse pollution losses, as it was able to reduce sediment and nutrient losses by 72–99% in four out of five site years trialled. Using information from the MOPS projects, this paper builds on the findings of Kay et al. to provide an updated picture of the evidence available and the immediate needs for research in this area. [Copyright &y& Elsevier]

Abstract: The European Water Framework Directive (EWFD) demands a detailed analysis to determine which changes and measures within the surface water system are required, which actors require detailed scrutiny, and which technology has to be developed in order to guarantee that the quality of the surface water is complying with this Directive. This paper will discuss a holistic model developed for the optimization of the surface water system for a water authority in The Netherlands, which is influenced by (i) waste water streams originating from e.g. households, industry, agricultural and transport activities among others and (ii) the end-of-pipe technology of waste water treatment plants, while interfacing with (iii) thermal treatment and minerals and metallurgical processing for the recovery of specific elements from waste water sludge and other residues created during waste water treatment. The paper develops a fundamental basis that can feed factual information such as optimal combination of measures (technology and policy) into sustainability frameworks or the implementation of the EWFD. This optimization is affected by quality constraints, costs, energy, environment and interactions between the various materials present in the different streams in the water system. By incorporating these parameters into the model a tool is provided that provides metrics to measure the ‘sustainability’ of the Web of Water (WoW), while linking to and harmonising with the Web of Materials/Metals (WoM). The WoW optimization model links material cycles from e.g. food, transport, agriculture and industry to the recovery of materials from the water cycle with the pyrometallurgical and thermal processing of minerals/materials, hence quantifying resource conservation and sustainability on the interface between aquatic and product manufacturing systems and the process industries. [Copyright &y& Elsevier]

Abstract: The Penman–Monteith (PMe) equation that estimates evaporation from leaf/canopy surfaces is based on a few approximations. Several authors discussed ensuing errors and suggested improvements. This paper reminds those discussions which ended in the early nineties. It compares linearized PMe− with non-linear iterative solutions and illustrates resulting deviations. It differentiates between deviations for daily and hourly evaporation rate estimates. The latter are found to be higher. It also demonstrates deviations obtained at two different altitudes above sea level. Considering present tendencies to refine evaporation estimates for practical purposes and making use of easily available methods for solving non-linear equations this paper offers a new method to estimate evaporation. In a first step, a simple algebraic term, the surface temperature control sum, is introduced to find approximate differences between air and evaporating surface (leaf, canopy) temperatures. It suggests to concentrate research on the r s /r a ratio. A new formula is derived for estimating leaf/canopy surface temperatures for non-water stressed plants. In a second step, the estimates of temperature differences are used to calculate evaporation estimates. This two-step approximation leads to appreciably smaller errors as compared to the PMe-solution over the full range of input parameters of agro-meteorological relevance. It is, however, less accurate than some of methods proposed in literature. The method is meant for practical application in agricultural water management. [Copyright &y& Elsevier]

Abstract: Agricultural Water Management began in 1976 with Dr. Jans Wesseling as Editor in Chief and Dr. N.A. de Ridder as Associate Editor. Dr. Wesseling stated the purpose of the journal in his editorial published in the first issue as follows: “that the new journal will contribute to the fruitful exchange of ideas and knowledge of the role of the most commonly occurring fluid in the world on the production of our daily food”. Papers about the role water plays in agriculture have been published based on national, regional, or even local studies of interest to the readers. In 1977, the first full year of publication, 19 papers were published. In 2005, that total swelled to 129. From the beginning through 2005, 1581 papers were published in 78 volumes including 15 special issues. The ambit of the journal has always been global, publishing results from industrialized and developing countries. In the first year, authors from 10 nations published papers in the journal; 44 countries were represented in 2005. People from 21 countries have served on the journal''s Advisory Editorial Board. The journal''s Impact Factor (based on how often its papers are cited) during the past decade has risen from 0.3 to 0.8. Since 2002, it has ranked in the upper half of the 55 journals in the Water Resources class according to Thomson Scientific. Electronic submission and review began in 2004. After registration, authors submit papers to http://ees.elsevier.com/agwat/default.asp, and reviewer comments, and manuscript revisions are conducted electronically under the supervision of the Editors in Chief. A web-based system enables authors in remote locations to submit manuscripts without any expenditure for photocopying or postage. It also speeds the publication process in an area of science that is rapidly evolving, and new work can be cited quickly when published in Agricultural Water Management. [Copyright &y& Elsevier]

Abstract: Wetlands contribute in diverse ways to the livelihood of many people in Africa. One of the major constraints to the wise use of African wetlands is lack of knowledge by planners and natural resource managers on the benefits that they provide and techniques by which they can be utilised in a sustainable manner. This paper presents findings from a study undertaken in Kilombero Valley, Tanzania, on the dynamics and benefits of natural resource use in the wetlands. The paper specifically focuses on opportunities and challenges related to integrated water resource management. The study was conducted in two villages, Idete and Signali located in Kilombero District, Morogoro Region. Participatory assessment and household interviews were employed to obtain both qualitative and quantitative information, respectively, pertaining to biophysical, agronomic and socio-economic facts that influence community access to, and utilisation of the wetland resources. The findings show that Kilombero Valley has high potential for a diversity of livelihood activities. The wetland also serves as a source of water for farming, livestock, fishing and for domestic uses. Over the last two decades the use of wetlands for agriculture has increased because of increasing population of both pastoral and agro-pastoral communities, and hence the resultant need to produce more food. However, there are environmental concerns associated with increasing use of wetlands for agriculture and other livelihood activities, including deforestation and trampling of soils by increasing livestock numbers, increased demand on the water resources and lack of elaborate institutional framework to facilitate the integration of the various sectoral and cross-sectoral uses of the wetland resources and among stakeholders. The main conclusion is that sustainable livelihood development of wetland communities requires multidisciplinary and integrated efforts in addressing constraints in the various sectors such as agriculture, natural vegetation use, water resources and fishing. [Copyright &y& Elsevier]

Abstract: The Wami Rivers basin is an important area due to its diversified use which benefits a multi-diversity of stakeholders. While large scale irrigated sugar production is the main issue of concern upstream, there are other equally important socio-economic activities which include biodiversity and environmental conservation, domestic water supply, livestock water needs, and fishing. A large water supply project has just been completed downstream of the Wami River to provide water for the Chalinze township and surrounding villages. Other important undertakings include irrigated rice farming in Dakawa area, livestock keeping activities, and the establishment of the Sadani National Park (SANAPA) and the Wami-Mbiki Wildlife Management Area (WMA). The Wami River basin forms significant parts of both the Wami-Mbiki WMA and the SANAPA wildlife conservation areas. Regardless of its importance, the basin is increasingly being degraded through deforestation for agricultural expansion, timber, and more important charcoal making. The basin is also being polluted through disposal of excess molasses from the sugar industry, and use of poisonous substances and herbs in fishing. The worsening environmental condition in the basin has become a health threat to both people in the surrounding villages and wildlife. To a large extent, such changes are intensifying poverty levels among the local population. These changes are raising concerns about the long-term environmental sustainability and health implications of the current water use competition and conflicts in the basin. The purpose of this paper is to examine the main water resource use conflicts and how they affect environmental sustainability in the long-run. It also intends to establish linkages between wildlife management, pastoralism, agricultural activities and how such linkages influence poverty alleviation efforts in the basin. An attempt has been made to examine the environmental and health implications of human activities in the basin in relation to poverty indicators, people’s lifestyle, and integrated water resource use in the Wami River basin. In the process of examining linkages and sources of conflicts, key strategies to harmonize the interests of various stakeholders and ensure integrated and sustainable use of the Wami River waters will be identified. As a conclusion to paper, issues related to population pressure, pollution, wildlife, pastoralism and many others will be discussed with the view of harmonizing the needs of various stakeholders and minimizing their effect on the river ecosystem. The discussion shows how poverty levels are linked to resources over-exploitation, hence limiting sustainability in the basin. Under the current poverty levels in almost all villages surrounding the Wami River basin, there is no alternative ways or technology to replace non-sustainable resource exploitation. Many villages depend on charcoal burning and selling as a survival strategy and source of income. [Copyright &y& Elsevier]

Abstract: Most of the Mwanga district is classified as semi-arid with a rainfall range of 300 and 600mm. Rainfall patterns in the district are unpredictable and are subject to great fluctuations. Like other semi-arid areas, the district is characterized with land degradation, unreliable rainfall, repeated water shortage, periodic famine, overgrazing, dry land cultivation in the marginal areas and heavy competition for limited biomass between farmers and cattle. Vulnerability here is high due to unreliability of weather. The people of Mwanga are dependent on agriculture for their livelihood. However agriculture is difficult in the area due to inadequate rainfall. For a very long time the people have been dependent on irrigation agriculture to ensure food security. Of late the traditional irrigation system is on the decline threatening food security in the area. This paper examines the state and status of the irrigation canal system in Mwanga district with the view of recommending ways in which it can be improved. The study used participatory, survey and in-depth interviews to obtain both quantitative and qualitative data. The major findings are that social, political, environmental and demographic bases that supported the traditional irrigation system have changed drastically. As a corollary to this, the cultural and religious belief systems that supported and guided the traditional canal system management have been replaced by mistrust and corruption in water allocation. In addition the ownership and management system of the water resources that was vested in the initiator clans has changed and now water user groups own the canals/furrows but they do not own the water sources. This has rendered the control of the water sources difficult if not impossible. Currently the system is faced by a number of problems including shortage of water and poor management as demand for water increases and this has led to serious conflicts among and between crop producers and pastoralists over water use. Water users and leaders are also not knowledgeable of the policy guiding water use, ownership and management implying their non-involvement in the policy formulation process. The paper concludes that the traditional irrigation system in Mwanga district that has cushioned people from food insecurity for a long time is under serious threat and something urgently needs to be done. The paper recommends modernizing the irrigation infrastructure, instituting a system of governance that takes on board the interests of all the stakeholders, involving local people and their leaders in the policy formulation process not as an “excess luggage” but as an organic part of the process. The recommendations can only be effected as an organic part of the holistic approach to eradicate poverty. [Copyright &y& Elsevier]

Abstract: Rainfall patterns in semi-arid areas are typically highly variable, both spatially and temporally. As a result, people who rely completely on rainwater for their survival have over the centuries developed indigenous knowledge/techniques to harvest rainwater. These traditional water-harvesting systems have been sustainable for centuries. The reason for this is that they are compatible with local lifestyles, local institutional patterns and local social systems. In order to develop sustainable strategies, it is therefore important to take into account of, and learn from, what local people already know and do, and to build on this. This paper explores how indigenous knowledge is used by farmers in the Makanya catchment, Kilimanjaro region, Tanzania to identify potential sites for rainwater harvesting (RWH). The paper draws on participatory research methods including focus group discussions, key informant interviews, field visits and participatory workshops. Initial findings indicate that farmers do hold a substantial amount of knowledge about the resources around them. As there are spatially typical aspects to indigenous knowledge, it could be extrapolated over a wider geographic extent. From the preliminary findings, it is being recommended that geographic information system (GIS) could be an important tool to collect and upscale the utility of diverse indigenous knowledge in the decision-making process. [Copyright &y& Elsevier]

• 3D hydrodynamic model was created in Hydrus for SWC simulation. • Water deficit of a maize field was determined based on temporal changes of SWC. • Optimized irrigation scheduling was presented for two different vegetation periods. • The model copes with changing meteorological circumstances in continental climate. Precision irrigation is becoming more and more important in agricultural crop production due to the limited water resources resulting from the negative effects of climate change. Modeling of irrigation can support decision makers in the maintenance of the quantitative and qualitative parameters of the cultivated crops, while improving the efficiency of water consumption. In the present paper, a 3D hydrodynamic model was created in the HYDRUS environment to support the modeling of the temporal changes and spatial variations in the water balance (WB) of a maize cultivated Hungarian study site, thereby providing inputs for irrigation scheduling and variable rate irrigation for stakeholders. Beside soil physical parameters, crop evapotranspiration (ET c) values were also considered as model inputs for the phenological crop development stages of the maize from the sowing to the harvesting. This period was between the 3rd of May and the 10th of September in 2020 and the 20th of May and 14th of September for the year 2021. The performance of the model for soil moisture conditions were validated by on-field soil moisture measurements. The overall performance (full vegetation period) of the model was good (r2 = 0.88 for 2020 and r2 = 0.91 for 2021), but slightly varied among different phenological stages. Based on the model, the water balance of the investigated area was determined without any irrigation, alongside the cumulative water fluxes (CWF) through the boundaries including the root water uptake (RWU) of the maize as well. The results revealed that the incoming precipitation was not sufficient to supplement the water content in the soil to the optimal soil moisture range, except when the precipitation level is high enough to balance it. It was concluded that the water balance was negative for the investigated time periods without any irrigation. The specific water deficit (WD) values were calculated considering the area of the study site, which is 1439 m3/ha for 2020 and 2068 m3/ha for 2021. From the obtained results, optimal irrigation schedules were presented to keep the soil moisture content in the optimal range (20.92–14.41 V/V%) in the modeled area for two different vegetation periods. It was found that due to the irrigation the crop water productivity (CWP) increased by 6% and 4% in 2020 and 2021. Overall, the model is able to cope with changing circumstances that could help to mitigate the negative effects of climate change with the reasonable use of limited water resources in the future. [ABSTRACT FROM AUTHOR]

• The paper provides a critical analysis of the appropriateness of water productivity (and intensity) as an indicator of water efficiency. • A decomposition analysis is performed for agricultural water productivity. • Data is compiled from agriculture sector from 34 countries with time series ranging from 1995–2010. • Labor productivity and capital intensity are the main drivers of water productivity, on the contrary, water efficiency has a minor impact. • Water productivity should not be used for the assessment of efficient water management strategies, policies and frameworks. Water productivity is broadly used as an indicator to measure the success of policies aiming at efficient water management. Focusing on the agricultural sector, this paper provides the first critical analysis of the appropriateness of water productivity for this type of assessment. We apply Logarithmic Mean Divisia Index (LMDI) decomposition analysis together with descriptive statistical analysis to test our main hypothesis that is natural resources do not generate value added, and therefore changes in water productivity are related to well-known drivers of economic growth rather than to improvements in water efficiency. We use three different models with different levels of decomposition detail to identify the drivers of water productivity changes. Results show that indeed there is a weak relationship between changes in water productivity and water efficiency. In contrast, changes in water productivity are driven by changes in labor productivity and capital intensity. Thus, we discourage policy makers from using the indicator to monitor the progress on efficient water management or on decoupling between economic growth and water consumption. Rather, indicators independent from economic development such as biomass per volume of water should be used and the absolute volumes of water appropriated by society monitored. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Constructed wetlands offer promising solutions for controlling nutrient pollution in agricultural systems with relatively low costs and energy inputs. In mainly central and northern Italy, semi-natural and reconstructed Free-Water Surface Constructed Wetlands (FWS CWs) are designed to treat nonpoint-source pollution from agricultural catchments. However, their performance depends on system design and time of establishment. This paper evaluates the efficiency of a recently established FWS CW to remove nonpoint-source nutrient pollution due to agricultural drainage in the low-lying Venetian plain (NE Italy). The system was established in 2014 by creating five consecutive sub-basins vegetated with macrophytes to restore a semi-natural wetland, and later monitored in terms of water quality parameters and nutrients removal over three consecutive agricultural seasons (2014–2016). Total (TN) and nitrate (N-NO 3 ) nitrogen concentrations showed peaks (16.37 and 15.31 mg l −1 for TN and N-NO 3 , respectively) in the various sub-basins during spring 2015, associated with fertilisation of surrounding croplands and intense rain events. Performance improved over the three years, with increasing median removals of TN (33.3–49.0%) and N-NO 3 (32.2–80.5%), corresponding to average mass of 1355 kg y −1 and 1011 kg y −1 for TN and N-NO 3 . Concentrations of ammonium (N-NH 4 ) and orthophosphate (P-PO 4 ) were generally low (<1 and <0.3 mg l −1 for N-NH 4 and P-PO 4 , respectively), with average yearly mass removals of 50 kg for N-NH 4 and 9 kg for P-PO 4 . According to the overall treatment performance, the FWS CW could treat a total area of about 30 ha with a wetland/catchment ratio of 7%. However, we expect that treatment efficiency will increase as a result of bank stabilisation and improvement of the aquatic environment, together with increases in surface vegetation. [ABSTRACT FROM AUTHOR]

In accordance with national policies, the Jiansanjiang Administration of Heilongjiang Province in China has assumed a heavy task of grain production in recent years. The spatial matching status of water and land resources is a prerequisite for grain production. To analyze the potential for grain production objectively, the matching characteristics of agricultural water resources and land resources in Jiansanjiang Administration were analyzed for this paper. The spatial distribution pattern of the water and land resources was analyzed, and the amount of broadly-defined agricultural water resources (BAWR) and cultivated area were introduced as the water resource and land resource quantity parameters, respectively. The Gini coefficient model for agricultural water and land resource matching and the model for measuring the matching index between the BAWR and land resources (MIBAWRLR) were then constructed to evaluate the degree of matching between agricultural water and land resources in Jiansanjiang Administration and 15 farms in the region. Based on the Cobb-Douglas all-factor production function, the input–output model of agricultural production was built, with the grain yield per hectare used as the explained variable and basic, technological, and natural factors as the explaining variables. The results are as follows: ① The results of the MIBAWRLR indicate that the matching situation between agricultural water resources and land resources in Jiansanjiang Administration has improved, which was consistent with the results of the Gini coefficient model. The matching situation on the farms of Jiansanjiang Administration worsened from south to north, and the spatial matching pattern was consistent with the spatial distribution of the proportion between blue water and green water at each farm, i.e., the matching situation on a farm with a high proportion of blue water was satisfactory. ② According to the input–output model of agricultural production, introducing the BAWR into the established models as the characteristic parameter of water resource quantity is scientific and reasonable. [ABSTRACT FROM AUTHOR]

This paper uses the water allocation economy in Israel as a proxy for imputing the value of agricultural amenities. A general equilibrium model is developed, and incorporates agricultural amenities as byproducts of agricultural production, water trade channels, and multiple water types. The premise is that until a decade ago, water policy in Israel was interlinked with agricultural land-use policy. Integrating a Monte-Carlo analysis, the model searches for a baseline minimum value of agricultural amenity that makes household, in the counterfactual scenario, indifferent between the administrative and market mechanisms. The minimum imputed value is around 109% agricultural output. The intuition is that the gains in economic welfare, from improved water use efficiency, are offset by the losses in social welfare due to a reduction in available agricultural amenities. [ABSTRACT FROM AUTHOR]

While agriculture places the greatest demand on water resources, increasing agricultural production is worsening a global water shortage. Reducing the cultivation of water-consuming crops may be the most effective way to reduce agricultural water use. However, when also taking food demand into consideration, sustaining the balance between regional water and food securities is a growing challenge. This paper addresses this task for regions where water is unsustainable for food production (Beijing-Tianjin-Hebei Region for example) by: (i) assessing the different effects of wheat and maize on water use; (ii) analyzing virtual water and virtual land flows associated with food imports and exports between Beijing-Tianjin-Hebei and elsewhere in China; (iii) identifying sub-regions where grain is produced using scarce water resources but exported to other regions; and (iv) analyzing the potentiality for mitigating water shortage via Land-Water-Food Nexus. In the Beijing-Tianjin-Hebei Region, the study reveals that 29.76 bn m 3 of virtual water (10.81 bn m 3 of blue virtual water) are used by wheat and maize production and 8.77 bn m 3 of virtual water used in nearly 2 million ha of cropland to overproduce 12 million ton of maize for external food consumption. As an importing-based sub-region with high population density, Beijing & Tianjin imported mostly grain (wheat and maize) from Shandong Province. Then, Hebei Province, as an exporting-based sub-region with severe water shortage, overproduced too much grain for other regions, which aggravated the water crisis. To achieve an integrated and sustainable development of the Beijing-Tianjin-Hebei Region, Hebei Province should stop undertaking the breadbasket role for Beijing & Tianjin and pay more attention to groundwater depletion. The analysis of the Land-Water-Food Nexus indicates how shifts in cultivated crops can potentially solve the overuse of water resources without adverse effects on food supply. It also provides meaningful information to support policy decisions about regional cropping strategies. [ABSTRACT FROM AUTHOR]

With the abolishment of the European Union milk quota system in April 2015, the Irish government has targeted a 50% increase in milk production by 2020 over 2007–09 levels. Resulting milk price volatility and environmental constraints are forcing farmers to produce milk at lower costs with a lower overall environmental footprint. This entails using less energy and water resources to maintain commercial competitiveness and to reduce the environmental consequences of the production. This paper presents a detailed analysis of electricity and direct water consumption of 58 pasture-based, Irish commercial dairy farms. Data was acquired through a remote monitoring system installed on each farm in 2014 alongside corresponding milk production, stock, infrastructural and managerial data. The results derived from the analysis of this data allow key drivers of both electricity and water consumption to be understood with the ultimate aim of generating data to develop footprint models, to achieve a reduction in electricity and water use and to improve the cost efficiency of Irish pasture based dairy farms. The analysis showed electricity use of 39.84 Wh L m −1 and water use of 7.43 L w L m −1 for the period Jan - Dec 2015. Dairy farm processes directly associated with milk production (milk harvesting and milk cooling) were responsible for 47% of overall electricity consumption. Milk cooling systems which utilised ice chiller units or ice bank milk tanks consumed 32% greater Wh L m −1 for milk cooling compared with direct expansion milk tanks. This increase in consumption was met with a 25% decrease in day-time hours consumption due to their load shifting capabilities resulting in no difference in milk cooling related cost per L m when under a day and night electricity tariff structure. Mean milk cooling electricity savings of 21% were achieved across farms with the incorporation of ground water through a plate heat exchanger for milk pre-cooling. However, in an open loop system, this resulted in a 41% increase in parlour water consumption. Electricity consumption was found to be largely associated with milk production, herd size (total dairy cows) and the number of lactating cows. Water consumption was found to be largely correlated with milk production and moderately correlated with herd size and the number of lactating cows. Decreased correlation strengths for water consumption compared to electricity suggests consumption is less dependent on milk production and stock numbers and more dependent on managerial processes, environmental conditions and farm infrastructure. Results and methodologies from this analysis will facilitate the development of adaptive predictive and optimisation methodologies for dairy farming electricity and water consumption. [ABSTRACT FROM AUTHOR]

Climate change will affect the future availability of water resources for agriculture. An understanding of the impact of future climate change on regional agricultural water use can provide a basis for regional agricultural production and water management. This paper evaluated the agricultural water demand under three future climate change scenarios in the Loess Plateau of northern Shaanxi (LPNS), China. The results showed that in the scenarios RCP2.6, RCP4.5, and RCP8.5, the temperature, effective precipitation, and relative humidity were on the rise, the wind speed decreased slightly, and the trend of sunshine duration was unclear. The irrigation water requirements of the main crops exhibited a downward trend under future climate change scenarios. The decreasing trend of the irrigation water requirement was highest in the RCP8.5 (−0.90%) scenario, followed by the RCP4.5 (−0.77%/year) and the RCP2.6 (−0.30%/year) scenarios. Based on the impact of the changes in the evapotranspiration of future crops and the effective precipitation in the RCP2.6 scenario, the irrigation water requirements of the agricultural industry showed a downward trend and decreased from 1.84 × 10 9 m 3 /year (2010–2014 average) to 1.29 × 10 9 m 3 /year (2040–2049 average); the irrigation water requirements of the agricultural industry showed a significant downward trend (P < 0.05) in the RCP4.5 and RCP8.5 scenarios, decreasing from 1.84 × 10 9 m 3 /year (2010–2014 average) to 1.20 × 10 9 m 3 /year (2040–2049 average) and 1.15 × 10 9 m 3 /year (2040–2049 average), respectively. Future research should be aimed at improving the regional climate downscaling and developing a better understanding of the responses of agriculture to regional climate change. [ABSTRACT FROM AUTHOR]

Water scarcity is one of the major environmental problems in Southern Europe. High levels of water stress and increasing frequency of droughts, along with a greater environmental protection, make it necessary to design water management strategies that are allocative efficient and balance supply and demand. When functioning markets cannot be developed, the allocation rules proposed in the literature of social choice have been recognized as a suitable alternative. However, the application of new water allocation rules can be impaired by a lack of acceptance and implementation problems. This paper examines these obstacles for the case of an agricultural water users association (WUA), situated in the basin of the River Ebro, in relation to the governance structure and collective decision rule of the WUA. It analyzes the extent to which the gains and losses of the farmers affect their acceptance, and examines conditions for building agreements with side payments that provide incentives for the majority of the farmers to form part of a possible agreement. The results show that the uniform and sequential rules improve the allocative efficiency under normal conditions compared to the status quo and the sequential rule even in the case of droughts. In the presence of side payments this rule is likely to be accepted and has only an insignificant impact on distributional inequality. [ABSTRACT FROM AUTHOR]

Agriculture and the eco-environment are increasingly competing for water. The extension of intensive farmland for ensuring food security has resulted in excessive water exploitation by agriculture. Consequently, this has led to a lack of water supply in natural ecosystems. This paper proposes a trade-off framework to coordinate the water-use conflict between agriculture and the eco-environment, based on economic compensation for irrigation stakeholders. A hybrid Bayesian network (HBN) is developed to implement the framework, including: (a) agricultural water shortage assessments after meeting environmental flows; (b) water-use tradeoff analysis between agricultural irrigation and environmental flows using the HBN; and (c) quantification of the agricultural economic compensation for different irrigation stakeholders. The constructed HBN is computed by dynamic discretization, which is a more robust and accurate propagation algorithm than general static discretization. A case study of the Qira oasis area in Northwest China demonstrates that the water trade-off based on economic compensation depends on the available water supply and environmental flows at different levels. Agricultural irrigation water extracted for grain crops should be preferentially guaranteed to ensure food security, in spite of higher economic compensation in other cash crops’ irrigation for water coordination. Updating water-saving engineering and adopting drip irrigation technology in agricultural facilities after satisfying environmental flows would greatly relieve agricultural water shortage and save the economic compensation for different irrigation stakeholders. The approach in this study can be easily applied in water-stressed areas worldwide for dealing with water competition. [ABSTRACT FROM AUTHOR]

By evaluating the eco-environmental resources of China's major grain-producing regions, the development status of the eco-environmental resources in major grain-producing regions of China was clarified. This is of great significance in maintaining green and sustainable agricultural development and ensuring food security. This paper takes 13 major grain-producing regions in China as the study area, constructs the eco-environment index system by using the Driver-Pressure-State-Impact-Response (DPSIR). The average annual growth rate represents the dynamic changes of each indicator, and the random forest model by using Jupyter Notebook is selected to evaluate the current state of development of the eco-environment resources from 2005 to 2020. The combination of dynamic and static evaluation of the eco-environmental resources is more conducive to decision makers to keep abreast of developments in the eco-environmental resources. The results show that: Firstly, there are differences between static and dynamic conditions that more number of important indicators in static conditions than in dynamic conditions, and the number of important indicators located at the driving force criterion level is higher. Secondly, under static conditions, the evaluation results of eco-environmental resources show an overall upward trend (4.10 in 2005 and 4.65 in 2020); under dynamic conditions, the evaluation results of eco-environmental resources show an overall downward trend (4.35 in 2005 and 4.13 in 2020). Thirdly, there are differences in spatial distribution. Under static conditions, the spatial distribution of regional eco-environmental resource levels is generally "high in the north and low in the south", while under dynamic conditions, it is "high in the south and low in the north". Finally, according to the different important indicators in the north and south, the northern region should develop plans to increase the penetration rate of agricultural mechanization and improve the efficiency of water resources utilization, while the southern region should pay more attention to the development of green agriculture, accelerate the construction of urbanization, and improve the efficiency of water resources utilization. • Comprehensively evaluated the eco-environment resources of main grain producing areas. • Using random forest model to evaluate ecological environment resources. • Use of average annual growth rate for velocity calculation in dynamic evaluation. • Determine the importance degree of regional index in dynamic and static conditions. • Analyzed regional development current situation and development potentiality. [ABSTRACT FROM AUTHOR]

Understanding future climate change is crucial for securing and managing water supplies necessary for agricultural activities in China, particularly in rainfed agriculture regions. This paper evaluates the projected climate change for nine major agricultural zones in China, using ensembles of regional climate models (RCMs) simulated under the Coordinated Regional Downscaling Experiment-East Asia second phase (CORDEX-EA-II) framework. The simulations were conducted for two climate scenarios (RCP2.6 and RCP8.5) at a 25 km grid spacing, with three RCMs (RegCM4, REMO, and WRF) driven by multiple CMIP5 global climate models (GCMs). The study compares the RCM simulations to the driving CMIP5 and the recent CMIP6 ensembles, focusing on surface temperature, precipitation, and surface relative humidity for the present day (1981–2010), mid-future (2036–2065), and far future (2070–2099) periods. The model evaluations indicate that the GCM and RCM simulations are consistent with observations, with RCMs showing better performance than the driving GCMs. The results show that both GCMs and RCMs project increased temperature and precipitation in most agricultural zones of China in the future, with the CMIP6 ensembles projecting the largest temperature increase and the CORDEX-EA-II ensemble showing the finest spatial details. Relative humidity is projected to decrease over major rice-producing areas of South China in the CORDEX-EA-II, CMIP5, and CMIP6 ensembles. This study provides valuable information to support climate change adaptation and mitigation efforts in China, particularly in the agricultural sectors. • CORDEX-EA-II simulations demonstrate better model performance over China. • Temperature and precipitation are projected to increase in the future. • Relative humidity is projected to decrease over South China. [ABSTRACT FROM AUTHOR]

Precise evapotranspiration (ET) estimation is critical for agricultural water management, particularly in water-stressed developing countries. Vapor Pressure Deficit is one of the ET parameters that has a significant impact on its calculation (VPD). This paper forecasts VPD using ensemble learning-based modeling in eight different regions (Dakahliyah, Gharbiyah, Kafr Elsheikh, Dumyat, Port Said, Ismailia, Sharqiyah, and Qalubiyah) in Egypt. In this study, six machine learning algorithms were used: Linear Regression (LR), Additive regression trees (ART), Random SubSpace (RSS), Random Forest (RF), Reduced Error Pruning Tree (REPTree), and Quinlan's M5 algorithm (M5P). Monthly vapor pressure data were obtained from the Japanese 55-year Reanalysis JRA-55 from 1958 to 2021. The dateset has been divided into two segments: the training stage (1958–2005) and the testing stage (2006–2021). Five statistical measures were used to evaluate the model performances: Correlation Coefficient (CC), Mean Absolute Error (MAE), Root Mean Square Error (RMSE), Relative absolute error (RAE), and Root Relative Squared Error (RRSE), across both training and testing stages. RF model outperformed the rest of the models [CC = 0.9694; MAE = 0.0967; RMSE = 0.1252; RAE (%) = 21.7297 and RRSE (%) = 24.0356], followed closely by REPTree and RSS models. On the other hand, M5P model performance remained moderate and both LR and AR model were the worst. During the testing stage, RF outperformed the rest of the models in terms of (which statistic), followed closely by REPTree and RSS models. On the other hand, M5P performance remained moderate and both LR and AR models were the worst. This study recommended using the RF model for future hydro-climatological studies in general, and vapor pressure deficit modeling and prediction in particular. This study enables future magnitudes to be predicted, alerting the authorities and administrators involved to focus their policy-making on more specific pathways toward climate adaptation. • Six machine learning models (LR, BART, RSS, RF, REPTree, and M5P) were developed for modeling VPD. • Long time series of eight Egyptian regions was used for estimation of VPD. • The RF model outperformed the rest models. • The performance of M5P and LR models was the second rank, while RSS model performance remained moderate. [ABSTRACT FROM AUTHOR]