Institutional management regimes for pricing of irrigation water: the French model — lessons for India

In France, the River Basin Committees and Water Agencies are in-charge of managing water resources. However, many surface irrigation networks were initiated and operated by the Regional Companies and farmer syndicates exclusively for agricultural development in the southwest of the country. These are water institutions playing an active role in water management with an objective of cost recovery in order to improve the quality of irrigation services to the users. The implementation of various innovative institutional management approaches by these agencies have yielded a modest degree of success in addressing the crucial problems of the irrigation sector in terms of pricing water, cost recovery, financial viability and overall sustainability of the surface irrigation system. This study attempts to examine the relevance of the institutional management approaches of France to the Indian context. The institutional framework for setting the price of irrigation water is through negotiation between the management and the user representatives. The important lessons drawn based on the experiences of the French model include the granting of financial autonomy to the water institutions in order to recover operational and maintenance costs, participatory approaches of decentralised management, user involvement in the decision-making process, devolution of small-scale irrigation networks to the users for management and the promotion of effective and viable user associations with access to technical information relating to the use of irrigation technologies.     

Asset Management for Irrigation Systems – Addressing the Issue of Serviceability

This paper advocates the need for defining criteria for level of service provision for irrigation networks and outlines a proposed Irrigation Serviceability Matrix to be used in the preparation of asset management plans and investment strategies for irrigation infrastructure. The development of the Irrigation Serviceability Matrix is based on experienced gained in the UK by the privatised water industry where the level of service provision to customers has become a key determinant for investment in infrastructure. The paper describes the evolution of this process within the UK water industry and its application to the irrigation sector.     

Factors influencing the stability of salt affected soils in the UK—criteria for identifying appropriate management options

Changes in agricultural practices that brought about deflocculation problems on salt affected alluvial soils in eastern England are outlined. The spatial variation in the occurrence of problems is discussed. Exchangeable sodium percentage (ESP) was found to be the factor having greatest influence on soil stability as measured by the dispersion ratio. Changes in ESP had similar effects on the stability of soils from Essex and Kent. Threshold ESP of 5% for topsoils and 10% for subsoils are suggested, above which deflocculation problems can be expected. The use of these thresholds as part of the process for identifying future management options is discussed.     

Does the adoption of zero tillage reduce greenhouse gas emissions? An assessment for the grains industry in Australia

The Australian Government has recommended that farmers move from cultivation-based dryland farming to reduced or zero tillage systems. The private benefits could include improvements in yields and a decrease in costs while the public benefits could include a reduction in greenhouse gas (GHG) emissions due to a diminution in the use of heavy machinery. The aim of this study is to estimate and compare total on-farm GHG emissions from conventional and zero tillage systems based on selected grain crop rotations in the Darling Downs region of Queensland, Australia. The value chain was identified, including all inputs, and emissions. In addition, studies of soil carbon sequestration and nitrous oxide emissions under the different cropping systems were reviewed.The value chain analysis revealed that the net effect on GHG emissions by switching to zero tillage is positive but relatively small. In addition though, the review of the sequestration studies suggests that there might be soil-based emissions that result from zero tillage that are being under-estimated. Therefore, zero tillage may not necessarily reduce overall GHG emissions. This could have major implication on current carbon credits offered from volunteer carbon markets for converting conventional tillage to reduced tillage system.     

Prototype time-domain reflectometry probes for measurement of moisture content near the soil surface for applications to “on-the-move” measurements

New time-domain reflectometry (TDR) probes were developed for estimating moisture conditions near the soil surface. Two types of probes, knife-shaped (K) and surface (S) types, were devised, and their performance was investigated in comparison with conventional rod-type probes. The K-type probe consists of two parallel, knife-shaped electrodes that can move in the shallow soil-layer without drawing out. The S-type probe looks like a sled with two parallel edges (electrodes), and can slide smoothly over the soil surface. This probe uses only the lower half of the electromagnetic field around the electrodes, but the estimates of moisture contents were comparable to those by conventional rod-type probes. The new probes would expand the applications of TDR principle especially to “non-penetrating” or “on-the-move” measurements of moisture conditions near the soil surface.     

Multi-factor Analysis of the Effective Precipitation for Crops in Semi-arid Region北大核心CSCD

【Objective】The purpose of this paper is to present a method to estimate the effective precipitation for crops in arid region.【Method】The model considered precipitation, soil and crop, and it was based on four modules: canopy interception, soil water tolerance, surface runoff, precipitation and deep percolation. The results calculated by the model were compared to those calculated from water balance using the data measured from the field. We applied the model to calculate spatiotemporal distribution of the effective precipitation for crops in five counties in Hebei plain.【Result】①The coefficient of determination (R2) and Nash-Sutcliffe efficiency (NSE) in all results were above 0.85, proving the reliability of the model. ②The effective precipitation for growing season of the wheat-maize in the five counties was 400.03 mm, and the infiltration coefficient of precipitation was 0.84. In wet, normal and dry year, the effective precipitation for crops was 419, 454 and 355 mm respectively, and infiltration coefficient of precipitation was 0.76, 0.86 and 0.83 respectively. The effective precipitation for crops in Luancheng and Yuanshi was higher than that for other counties.【Conclusion】The proposed model was reliable for estimating effective precipitation for crops at large scale in semi-arid region. © 2019 Authors. All rights reserved.     

The Open Laboratory of the State Machinery Industry for Mechanical Structural Security and Reliability

The Open L aboratory of the State Machinery Industry for Mechanical Structural Security and Reliability was establishedon the basis of the Mechanical Strength Center of Chinese Academy of Agricultural Mechanization Sciences according to thespirit of the Docum ent of Ministry of Technology(No.14 9,2 0 0 0 ) and Document of the State Administration of MachineryIndustry(No.30 0 ,2 0 0 0 ) .The prim ary task of the Open L aboratory is to conductresearch on the design theory and m ethodo…     

Farmer participation in irrigation – 20 years of experience and lessons for the future

This article examines trends in the understandingof and policies toward farmer participation in irrigationmanagement over the past 20 years, with special attention toexperiences with induced participation and management transferprograms in the Philippines, Sri Lanka, Pakistan, Senegal,Columbia Basin USA, and Mexico. Key lessons relate to the valueof social organizers as catalysts; the role of the irrigationagency as partner; and the enabling conditions for participation.As levels of income and infrastructure rise, we can expect moreformal organizations that enable farmers to deal with bankaccounts, service contracts, water rights, water markets, andadvanced technology in irrigation systems. The impact ofparticipation on irrigation performance needs to be evaluated notjust in terms of reductions in government costs, but by whetherimprovement in physical structures and farmers control overwater are great enough to offset the farmers costs ofparticipating.     

Options for alternative irrigation water supplies in the Murray–Darling Basin,Australia: a case study of the Shepparton Irrigation Region

Irrigated agriculture in the Murray–Darling Basin (MDB) currently faces serious challenges due to water scarcity, degradation of water quality, waterlogging and salinity resulting from inappropriate water and land use practices. In particular, there is now increasing risk of water quality degradation due to nutrient rich drainage water in the river system. Therefore, the future of irrigation will depend on the strategies that protect water quality and make best use of water available in the Basin. In this paper, we examine various options that irrigators have to augment water supplies on their farms using the Shepparton Irrigation Region (SIR), Victoria, as a case study. Here, we also discuss the suitability of the ‘Drainage Water Storage Scheme’ (DWSS) in providing additional water supplies to irrigators and in reducing the risk of water quality degradation due to flow of nutrient rich runoff into Basin’s river systems.     

Water–yield relationships and optimal water management for winter wheat in the Loess Plateau of China

High evaporative demand and limited precipitation restrict the yield of winter wheat (Triticum aestivum L.) grown in the Loess Plateau of China under semiarid climatic conditions. Grain yield can be improved by effective water management practices. A 13-year field experiment was conducted at the CERN Changwu Agro-ecological Experimental Station of the Loess Plateau to determine optimal irrigation strategies under limited water supply and to develop relationships among grain yield (Y), seasonal evapotranspiration (SET) and water-use efficiency (WUE). The experiment consisted of five irrigation treatments and three blocks. Measurements included grain yield, soil water content at various depth intervals in the 0–3,000 mm layer, irrigation amount, and precipitation. Results showed that winter wheat grown in this area experienced serious water stress during critical growth stages for the no-irrigation treatment. The amount and timing of irrigation had an important effect on grain yield, but significant differences in yield were not observed between the three-irrigation and the four-irrigation treatments. Grain yield was linearly related (R²=0.66) to SET, but differences in WUE were not significant for any of the treatments. The relationship between WUE and Y was best represented by a second order polynomial (R²=0.65) consisting of a nearly linear portion between 1.5 and 5.0 Mg ha^–1. Optimum water management of winter wheat in the Loess Plateau should consist of three 87.5 mm irrigations applied at stem elongation, booting, and anthesis.Communicated by J.E. Ayars     

Precipitation or water capacity indices? An analysis of the benefits of alternative underlyings for index insurance

Eastern Germany is often hit by drought causing income risk for crop farmers. Index-based risk management instruments could help crop farmers to reduce their farm income risk. Such instruments have some important advantages over damage-based insurance, like e.g. less moral hazard and adverse selection. At the same time they typically have a high level of basis risk. Up to now, mainly precipitation-based weather derivatives have been discussed as an appropriate risk management instrument for farmers in Germany. As a potentially more effective alternative, we propose water capacity-based index insurance. In order to show the benefits of a precipitation-based and water capacity-based index insurance, several contract designs are compared. Using a whole farm risk program planning approach, we show that for an average agricultural producer in Eastern Germany water capacity-based index insurance offers greater benefits than precipitation-based index insurance.     

面向全生命周期的信息化项目管理系统设计探究Research on the Design of Information Project Management System for the Whole Life Cycle 北京市数字农业农村促进中心

信息化项目的全生命周期包含从信息化规划、项目申报、立项、实施到最终验收以及后续运维等一系列过程,随着信息化项目的日趋复杂,对信息化项目管理的内容和形式也都提出了更高的要求。本文阐述了系统的设计原则、需求分析及技术体系架构等方面的内容,系统满足农业信息化项目过程管理、项目文档管理的业务需求和功能需求,提高了市农业农村局信息化项目的管理效率。     

Experimental Study of the Suitable N-fertilizer Amount for Corn under Drip Irrigation in Aeolian Sandy Soil北大核心CSCD

【Objective】The purpose of this paper is to determine the suitable N-fertilizer amount for corn under drip Irrigation in Aeolian sandy soil. 【Method】The experiment was conducted in a field, and the amount of water and N-fertilizer were selected as experiment factors. Two levels of water amount (high and low) and three levels of N-fertilizer dosage (high, middle and low) were scheduled and thus six treatments were carried out. Effects of treatments on the growth and yield of corn were studied. 【Result】The results showed that, under low watering condition, increasing N-fertilizer amount was good for plant growth and had higher plant height and larger leaf area index, while under high watering condition, the positive effects were limited. Under both water condition, the fresh and dry weight of over ground part increased as N-fertilizer application increased, while its water contend, stem diameter and SPAD litter varied. Besides, higher N-fertilizer amount was beneficial to get longer ear, larger diameter, and more seeds, also was likely to got higher yield. The yield of high N-fertilizer amount under low and high watering condition were 13.0 and 13.7 t/hm2 respectively, 20.4% and 17.1% higher than the yield of low N-fertilizer amount treatments. 【Conclusion】In Aeolian sandy soil, higher N-fertilizer amount would be conducive plant growth and yield, especially when irrigation water was limited. Therefore, according to the experiment, N-fertilizer amount of 300 kg/hm2 was recommended in Aeolian sandy soil of northwest Liaoning. © 2019 Journal of Irrigation and Drainage. All rights reserved.     

Devaluating Drainage Design Parameters for the Fourth Drainage Project, Pakistan by using SWAP Model: Part I – Calibration

A transient drainage simulation model,SWAP, was used to evaluate the performanceof drainage systems in (semi-) arid zones.Before application, the model wascalibrated by using 14-months datacollected from two sample fields of theFourth Drainage Project (FDP), Punjab,Pakistan. During the calibration process,emphasis was given to the accuratedetermination of soil hydraulic parameters,reference evapotranspiration, drainage fromsample fields and bottom boundarycondition. Laboratory determined soilhydraulic parameters were foundnon-representative of the field conditions.Difference between laboratory and fielddetermined soil water retention curves werefound significant. The pressure heads andsoil water contents measured in depthincrements of 15 cm were in good agreementwith the simulated values after applying afield measured retention curve. A closeproximity was also found between measuredand simulated average root zone salinity at0–1.0 m depth. The referenceevapotranspiration calculated by thePriestly-Taylor (PT-ET _o) methodwas found physically more realistic thanthe Penman-Monteith (PM-ET _o)method due to ignorance of the feed backmechanism of vapor pressure deficit onstomatal closure. The simulated cumulativedrainage from two sample fields wascomparable with the calculated values. Theanalysis of piezometer data shows thatthere is a negligible water exchangebetween the deep aquifer and theunsaturated zone. Therefore for scenarioanalysis, no flow conditions at the bottomof the soil profile can be applied as abottom boundary.     

Surface energy balance using satellite data for the water balance of a traditional irrigation—wetland system in SW Iran

A water balance of a large traditional irrigation area and a downstream adjoining wetland was determined using the surface energy balance approach (SEB), based on satellite data, to calculate the actual evaporation of both the irrigated area and the wetland at four different dates in a dry year and information of two additional images. The contribution of capillary flow by the shallow groundwater table was estimated by evaluating the actual evapotranspiration values of adjoining rangelands and non-inundated wetland areas. Those values were used to separate the total evapotranspiration into a soil moisture change component due to capillary rise, and into a component attributable to supply of river water. The only field data used for the estimated monthly water balance were air temperature, wind speed, and water inflow, since rainfall and outflow could be ignored in the year 2000. The results provided an insight for conditions of a drought year within the irrigated area, the distribution of water to irrigation and the wetland and showed the linkage between inundated wetland area and discharge.     

Optimisation model for water allocation in deficit irrigation systems: II. Application to the Bémbezar irrigation system

In this paper, the proposed optimisation model is applied to optimise water management in the Bembézar system, a small hydrological basin belonging to the Guadalquivir River basin in southern Spain that supplies water to the Bembézar River Irrigation District.In order to apply the model, the irrigation methods and performance in the irrigation district have been analysed through a set of field irrigation evaluations. Cropping patterns, crop productivity and other relevant agronomic and economic data have been collected.The influence of irrigation uniformity and the type of distribution of irrigation water on the crop yields, as well as the relationship between crop yields and irrigation scheduling have been analysed using the proposed model.A deterministic analysis has been carried out in the irrigation district in order to compare optimum water and cropping patterns management with actual ones.In order to account for the randomness of both climatic and water availability variables, a stochastic data generation has been carried out which considers the correlation between these hydrological series. The system is then analysed in a stochastic environment. Several simulations of the optimisation process have been carried out using generated data on climatic and water availability variables.The result of this analysis demonstrates that when only the satisfaction of the internal demands is considered, high quantities of water are allocated to the irrigation districts resulting in low economic benefits per unit of water used and lower irrigation efficiency. This situation has been compared with the solution provided by the hypothesis of a proposed water market in which it is possible to transfer part of the water of the system to other alternative uses at a fixed price. In this second hypothesis, water consumption in the irrigation districts was reduced.     

Evaluating Drainage Design Parameters for the Fourth Drainage Project, Pakistan by using SWAP Model: Part II – Modeling Results

This paper presents the results of modelsimulations to evaluate drainage designparameters for the Fourth Drainage Project(FDP), Punjab, Pakistan. The SWAP model wasapplied to compute the effects of landdrainage (12 combinations of drain depthand spacing) on soil moisture conditions inthe root zone and their effect on cropyield and soil salinization. For theconditions considered, the selection ofdrain depth is found to be more criticalthan that of drain spacing. Deeper drainsperform technically better in relation tocrop growth and soil salinization. Theoptimum drain depth for the multiplecropping system of the FDP-area was foundto be 2.2 m. This drain depth will producereasonably good crop yields at rather lowdrainage intensity while keeping the rootzone salinity within acceptable limits.This drainage design also maintained thegroundwater table depth below the root zonethroughout the growing season. The outcomeof this study reveals that the drainagedesign criteria applied for the FDP israther conservative with high drainageintensity. The FDP-area can effectively bedrained with a 25 percent lower drainageintensity (q _drain/h)provided no operational or maintenanceconstraints are present. However, the finaldecision on the optimum combination ofdrain depth and drain spacing would requirea thorough economical analysis. Thenon-steady state approach proved successfulin analyzing the complex interactionsbetween irrigation and drainage components.It is a valuable tool to optimize thedesign of drainage systems against cropyields and soil salinization.     

Could deficit irrigation be a sustainable practice for quinoa (Chenopodium quinoa Willd.) in the Southern Bolivian Altiplano?

The application of deficit irrigation (DI) to stabilize yield and to increase water productivity of quinoa (Chenopodium quinoa Willd.) raises questions in the arid Southern Altiplano of Bolivia where water resources are limited and often saline. Rainfed quinoa and quinoa with irrigation restricted to the flowering and early grain filling were studied during the growing seasons of 2005–2006 and 2006–2007 in a location with (Irpani) and without (Mejillones) water contribution from a shallow water table. It was found that the effect of additional irrigation was only significant above a basic fulfillment of crop water requirements of around 55%. Below this threshold, yields, total water use efficiency (TWUE) and marginal irrigation water use efficiency (MIWUE) of quinoa with DI were low. Capillary rise (CR) from groundwater was assessed using the one-dimensional UPFLOW model. The contribution of water from capillary rise in the region of Irpani ranges from 8 to 25% of seasonal crop evapotranspiration (ET_c) of quinoa, depending mostly on the depth of the groundwater table and the amount of rainfall during the rainy season. DI with poor quality water and cultivation of crops in fields with a shallow saline groundwater table pose a serious threat for sustainable quinoa farming. To assess the impact of saline water resources, soil salinity and required leaching were simulated by combining the soil water and salt balance model BUDGET with UPFLOW. The results indicate that irrigation of quinoa with saline water and/or CR from a saline shallow water table might, already after 1 year, result in significant salt accumulation in the root zone in the arid Southern Altiplano. A farming system with only 1 year fallow is often insufficient to leach sufficient salts out of the root zone. In case the number of fallow years cannot be increased, leaching by means of an important irrigation application before sowing is an alternative. Although potentially beneficial, DI of quinoa in arid regions such as the Southern Bolivian Altiplano should be considered with precaution.     

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