On-farm Irrigation Research Articles

Studying uniform and variable rate center pivot irrigation strategies with the aid of site-specific water production functions

Irrigation management has evolved into a top priority issue since available fresh water resources are limited. Water production functions (WPFs), mathematical relationships between applied water and crop yield, are useful tools for irrigation management and economic analysis of yield reduction due to deficit irrigation. This study aimed at (i) designing and evaluating site-specific WPFs (using k nearest neighbors (k-NN), multiple linear regression, and neural networks), (ii) simulating yield maps for uniform, sector control VRI, and zone control VRI center pivot systems using the site-specific WPFs, (iii) using the best WPF to investigate different cotton irrigation and zoning strategies using integer linear programming, and (iv) comparing soil-based and WPF-based zones for sector control VRI systems. A two-year cotton irrigation experiment (2013–2014) was implemented to study irrigation-cotton lint yield relationship across different soil types. The site-specific k-NN WPFs showed the highest performance with root mean square error equal to 0.131Mgha−1 and 0.194Mgha−1 in 2013 and 2014, respectively. The result indicated that variable rate irrigation with limited sector control capability could enhance cotton lint yield under supplemental irrigation when field-level spatial soil heterogeneity is significant. The temporal changes in climate and rainfall patterns, however, had a great impact on cotton response to irrigation in west Tennessee, a moderately humid region with short season environment. We believe site-specific WPFs are useful empirical tools for on-farm irrigation research.

Adaptation of pressurized irrigation networks to new strategies of irrigation management: Energy implications of low discharge and pulsed irrigation

This paper analyzes the consequences of adopting new on-farm irrigation management strategies (low discharge rates, long irrigation times and high frequencies) in an existing on-demand and sectorized pressurized irrigation system in eastern Spain. The sectorized behavior of the network was analyzed using two criteria: (i) the operating sectors obtained in a first stage by arranging the hydrants depending on their altitude respecting the pumping station and (ii) the operating sectors obtained by means of an optimization process. The Simulated Annealing combinatorial metaheuristic optimization technique was employed to find the best solution. Random on-demand patterns were generated using a Montecarlo simulation. The hydraulic requirements of the network were analyzed in every scenario by the Epanet 2.0 engine. The effect on energy consumption, power requirements and energy costs was assessed taking into account the electricity tariff billing structure. It was found that reductions in emitter discharge (qe) and Energy consumption (E)-Energy Cost (EC) savings are not inherently related to each other. Certain amounts of E and EC could be saved when the number of sectors and operating time parameters were properly selected. Pulsed irrigation in the current scenario showed an energy saving potential of 10.67, 6.43 and 6.99% for power capacity, E and EC, respectively.

Measuring the Erosion of an Irrigation Reservoir Levee

<abstract> <b><sc>Abstract.</sc></b> Increasing agricultural demands on limited groundwater resources in the Arkansas and Mississippi alluvial floodplain have created a growing need for the development of surface water resources. On-farm irrigation reservoirs are used to reduce dependence on groundwater supplies, but wind-induced wave erosion of levees creates an additional maintenance cost for producers. Measurements of levee erosion in a typical irrigation reservoir in east-central Arkansas were made with a ground-based LIDAR system and used to quantify erosion and estimate maintenance costs for irrigation reservoir levees. Approximately 1350 m³ of soil loss was measured from a 1530 m long levee during a seven-month period between December 2012 and July 2013. The damage was most severe in the northeast corner, where over 3 m of width were lost due to prevailing southerly winds blowing across the longest diagonal fetch length. Based on a typical cost (in 2014) for earth moving of $2.6 m^-3, the cost to repair this loss would be approximately $3,500, resulting in a five-year maintenance cost of $17,500, which is about 16% of the initial cost of the levee. This research provides a basis for decision-making for producers who rely on irrigation reservoirs. Maintenance costs can be projected for a worst-case-scenario of levee erosion, and the cost of protection can be balanced against expected erosion and repair costs.

Adaptation of Soil Spectral Reflectance Technique for Monitoring and Managing of Center-Pivot Irrigation Water

Center pivot irrigation system has the potentiality for economically net –return of various crop patterns, although it’s higher fixed costs inputs. Therefore, water management under the specified center pivot irrigation system can play a crucial role in maximizing water unit productivity and enhancing physical-agricultural resources sustainability. Hereby, the aim of this research was to evaluate the optional of a general reflectance model based solely on soil moisture distribution pattern as a key for on-farm irrigation management under center pivot irrigation system. Data revealed that the relative reflectance was strongly correlated with soil moisture contents. However, the best correlation was found act high soil moisture level between the reflectance values of 700 nm (Red-NIR) wave length and the volumetric water content (R² = 0.9). Moreover, the observed data could help to quality the strong in influence of soil moisture on spectral reflectance and absorption features and should aid in the development operational and management algorithms of on-farm irrigation systems.

A Developed Criterion for Rationalizing On-Farm Irrigation Water Uses Under Arid Conditions

Exploitation of irrigation water under arid ecosystem conditions becomes the pedagogical problem; therefore, rationalizing irrigation and maximizing water use efficiency based on appropriate developed technologies are the most important aspects in the water and agricultural policies. Therefore, the objectives of this study were to: 1) develop out a criterion to identify irrigation system effectiveness by using a dimensionless analysis; and 2) validate the suggested criterion. Dimensional analysis outputs revealed that the irrigation efficiency, may be better if it replaced by new developed terminology noted as irrigation effectiveness for calculating the seasonal crop water requirements (SCWR) that represent a ratio of irrigation system performance and irrigated soil characteristics. The developed criterion may be expressed as follows: Moreover, results analysis of the validation process of the application of the developed criterion indicated that SCWR had been improved by applying the developed criterion with about 10.55 – 21.56% comparing with the conventional method that had been recommended by FAO.

Incorporating the Irrigation Demand Simultaneity in the Optimal Operation of Pressurized Networks with Several Water Supply Points

Network sectoring is one of the most effective measures to reduce energy consumption in pressurized irrigation networks. In this work, the previous model focused on the irrigation networks sectoring with several supply points (WEBSOM), which considered the simultaneous operation of all hydrants, has been improved by integrating an analysis of multiple random demand patterns and their effects on variability in hydrant pressure (extended WEBSOM). The extended WEBSOM has implied a multiobjective optimization, followed by a Montecarlo procedure to analyze different flow regimes using quality of service indicators, a novelty for multi-source pressurized irrigation networks. This innovation has involved energy savings ranging from 9 to 15 % with respect to the consideration of the concurrent operation of all hydrants, which rarely occurs in on-farm irrigation systems. These energy savings were associated with maximum values of pressure deficit of 21 and 34 % in the most critical hydrant with a deficit frequency of 27 and 36 % in the peak month. However, smaller and less frequent deficits were achieved in the rest of the months. Thus, substantial energy savings can be obtained in irrigation districts without significant losses in the service quality provided to farmers.

The Modernization of a Large Irrigation Perimeter to Support Rural Sustainable Development - study Case of Matala (South of Angola)

Matala Irrigation Perimeter (MIP), located in the Cunene river basin, Huíla Province, South of Angola, is under a modernization process, managed by the Angola government. It aims a sustainable rural development, focusing on the socioeconomically aspects and the reduction of poverty of the local populations. This paper describes the MIP and presents the main results of a research study carried out to evaluate this process to establish actions for its improvement. It includes procedures for better water use at conveyance network and on-farm levels, and for higher land productivity through the improvement of crop systems. MIP has an area of 10,732 ha, being the water diverted from the Matala dam, in Cunene River. The irrigated perimeter was built in the 1960s, with a gravity canal distribution system, designed for traditional surface irrigation methods. Since 2002, the MIP was deeply rehabilitated, through the recovery of the main canal and water control structures, the enlargement of the irrigated area and the implementation of agro industrial and animal production units. MIP has several constraints, related with the maintenance of hydraulic structures, the effectiveness of water distribution, and shortage water supply. The main crops grown are potato, tomato, maize, pasture, horticultural and fruit trees, being their irrigation scheduling analysed. The development of on-farm irrigation has been set as an important priority, because the majority of the area applies low effective traditional methods. The modernization of the surface irrigation is a key crucial option, particularly in the flat soils with topographic conditions for gravity supply. The micro irrigation, particularly the drip irrigation, is applied in tomato crop and fruit tree, and the fixed or centre pivot systems used for maize and pastures. The research presented in this paper evaluated those systems, the performance indicators and the main difficulties found, including the requirements of farmer's technical support.

Assessing greenhouse gasses emitted from on-farm irrigation pumps: Case studies from Egypt

Abstract Increasing greenhouse gas emission has become a worldwide concern as it is considered a major driver of global warming and climate change. Clear picture of greenhouse gasses emissions due to utilizing energy for on-farm irrigation pumps is a key guide for decision makers to identify strategies for greenhouse gasses emission reduction that consequently impact on the national and international level. The current study determined the carbon emitted from three common categories of diesel and electric on-farm irrigation pumps in Egypt. A set of environmental, economic, and social evaluating indicators were applied to carry out a comparative analysis among the pump categories in three study areas at El-Behera Governorate. The study showed that pumping 1 m 3 of water for irrigating the cropping pattern at the study areas produces an average of 690 ton CO 2 . The study illustrated that electrical pumps are more environmentally, economically, and socially advantageous than diesel pumps.

English

English

Institutional design in transformation: A comparative study of local irrigation governance in Uzbekistan

The irrigation sector constitutes the backbone of Uzbekistan's economy, providing social and economic stability in the region. The sector collapsed with the fall of the Soviet Union, due to worsening of infrastructure conditions causing tensions among resource users. Subsequent irrigation management reforms were implemented in a top-down manner. More than a decade after the initial reforms – which established local Water Consumers Association (WCA) and transferred operation and maintenance responsibilities for on-farm irrigation canals – the poor performance of these associations is still apparent, illustrating the heritage of the strong role of state agencies in Uzbek water management that still affects collective irrigation management today. This paper identifies the necessary and sufficient conditions for successfully managing common pool resources (CPRs) and, more specifically, irrigation canal maintenance in the rural Bukhara region of Uzbekistan. Fifteen WCAs were examined regarding conditions that may facilitate successful irrigation canal maintenance. Methods involved focus group discussions and in-depth interviews with the associations concerned. Data gathered was analyzed using fuzzy-set qualitative comparative analysis. The results indicate that two paths of local factors can lead to well-maintained irrigation canals: (1) the combination of appropriate chairmanship skills with sustainable resource appropriation or (2) the combination of appropriate chairmanship skills with the presence of effective participatory governance. The results also illustrate the role of path-dependence and traditional co-production of irrigation management in Uzbekistan.

CENTER-PIVOT IRRIGATION WATER MANAGEMENT BASED ON SOIL SPECTRAL REFLECTANCE TECHNIQUE

Center pivot irrigation system has the potentiality for economically net return of various crop patterns, although it’s higher fixed cost’s inputs. Therefore, water management under the specified center pivot irrigation system can play a crucial role in maximizing water unit productivity and enhancing physical agricultural resources sustainability. Hereby, the aim of this research was to evaluate the optional of a general reflectance model based solely on soil moisture distribution pattern as a key for a farm irrigation management under center pivot irrigation system. Data revealed that the relative reflectance was strongly correlated with soil moisture contents. However, the best correlation was found act high soil moisture level between the reflectance values of 700 nm (Red-NIR) wave length and the volumetric water content (R²=0.9) at the short time (one hour). Moreover, the results of this study help to appear the strong in influence of soil moisture on spectral reflectance and absorption features and should aid in the development operational and management algorithms of on-farm irrigation systems.

Water conveyance and on-farm irrigation system efficiency gains in southern Alberta irrigation districts from 1999 to 2012

Efficiency gains from on-farm irrigation system upgrades and canal rehabilitation in southern Alberta irrigation districts are influenced by weather variability. The Irrigation Demand Model was used to estimate differences in on-farm demand and conveyance losses based on irrigation district characteristics in 1999 and 2012 using weather data from 1928 to 2012. Monte Carlo simulations were subsequently performed to determine the magnitude of potential efficiency gains at different chances of exceedance. Changes in irrigation systems and water conveyance infrastructure reduced gross demand by 74 mm from 1999 to 2012, with a 55-mm reduction in on-farm demand and a 19-mm decrease in conveyance losses at a 10% chance of exceedance. Reductions in gross demand on a volume basis from 1999 to 2012 ranged from 170 to 200 million m3, even with about 30,300 ha of irrigation expansion. Conveyance loss reductions were stable at about 50 million m3, so 70 to 75% of the potential water savings were achieved through reduced on-farm demand. Mean seasonal naturalized flows available for use in southern Alberta from 1912 to 2009 ranged from 2.08 billion m3 in high-demand years to 3.95 billion m3 in wet years. Gross demand based on irrigation district characteristics in 2012 varied from 1.73 billion m3 in wet years to 2.83 billion m3 in high-demand years. Additional gains in efficiency from on-farm irrigation system upgrades and rehabilitation of conveyance infrastructure in the future will help mitigate the increased risk of water scarcity as irrigation districts expand with current licensed water allocations.

Factors to Influence a Community&apos;s Choice for On-farm Irrigation Facility Management Responsibility Assignment to All Households within the Community in Japan: Panel Data Analysis using Rural Community Cards

Factors to Influence a Community&apos;s Choice for On-farm Irrigation Facility Management Responsibility Assignment to All Households within the Community in Japan: Panel Data Analysis using Rural Community Cards

Toward precision irrigation for intensive strawberry cultivation

The Doñana area in Southwestern Spain has the largest concentration of strawberry producers in Europe. The annual yield, close to 300,000t, is mainly devoted to the international markets (more than 90%). Due to the high water demand of strawberries and to the environmental concerns of the destination countries, the maximization of water use efficiency is critical for the strawberry sector.Aiming at the efficient water use in the strawberry production, a comprehensive drip irrigation system has been designed, according to precision irrigation principles. The system has been developed based on a three stages methodology. First, the irrigation process carried out by farmers has been assessed to identify inefficiencies in the irrigation system and management. Their performances have been evaluated using indicators such as the Relative Irrigation Supply (RIS), Strawberry Irrigation Water Applied (SWA) and Strawberry Water Footprint Applied (SWFA). The second phase is focused in an accurate irrigation scheduling based in precise crop water requirements estimation and the optimum irrigation pulse design. Finally, the irrigation system has been designed with the prevailing wisdom of meets the needs of the crop in a timely manner and as efficiently and as spatially uniformly as possible. The most appropriate drip irrigation emitters for the particular conditions of the strawberry production in the study area have been selected. The rest of the on-farm irrigation technologies required to control the system have been integrated, including soil water sensors, smart water meters, programmers, electrovalves and weather station. This precision irrigation system has been installed in a commercial strawberry farm during the irrigation season 2013–2014.Also, an application for PC, mobiles and tablets has been developed to provide farmers practical information (e.g. irrigation times) for optimal irrigation scheduling.

Irrigation Management in the Pamirs in Tajikistan: A Man's Domain?

Families living in Gorno-Badakhshan—situated in the Pamir Mountains in Tajikistan—depend on irrigated agriculture to meet their subsistence needs. Because men predominate, and are most visible in, the operation and management of irrigation systems in this region, water-related activities are often labeled as masculine. Yet women historically played an important role in on-farm irrigation activities and even formed the majority of the agricultural workforce during the Soviet period. Today women are still responsible for the bulk of farming activities, including irrigation. This is partly a consequence of the difficulty of depending on farming alone for making a living, which leads many men to migrate elsewhere in search of employment. Drawing on 6 months of fieldwork in 2 villages in different irrigation systems, this article argues that although formal water rights and power are vested in men, this does not mean that women lack agency, nor is it necessarily a reflection of wider gender inequities. Understanding the power and equity implications of formal distributions of rights and powers among men and women requires an analysis that links formal rights to actual irrigation and farming practices and places them in broader historical and livelihood contexts.

Special Issue on Trends and Challenges of Sustainable Irrigated Agriculture

Special Issue on Trends and Challenges of Sustainable Irrigated Agriculture

USING BISM MODEL TO CALCULATE WATER REQUIREMENTS FOR SOME VEGETABLE CROPS IN EGYPT

Agriculture water demand is one of the serious pressures on watersector in Egypt, since 85% of total available water is consumed inagriculture and most of the on-farm irrigation systems are low efficientcoupled with poor irrigation management. The objective of this paper is tocalculate water requirements for 12 vegetable crops grown in 17Governorates in Egypt. These crops were cabbage, celery (winter andsummer), spinach, potates (winter and summer), carrot (winter andsummer), cucumber (winter and summer), pepper (winter and summer),strawberry, eggplant (winter and summer), tomato (winter and summer),sweet melon and artichoke. BISm model was used to calculateevapotranspiration, crop factor and crop evapotranspiration for each crop ineach Governorate. The BISm application calculates ET using the PenmanMonteith equation, water requirement for each crop was calculated undersurface irrigation with application efficiency 60%. The results showed thatusing BISm to calculate water requirements of some vegetable crops inEgypt were low values in the Nile Delta Governorates, in the other hand, itsstarted to increase as we go to south (Middle and Upper Egypt), theseresults could be useful for farmers, extension workers and large farmsproduce vegetables for export. Large applied amount of irrigation water tovegetables could negatively affect quality. Thus, it is very important tocalculate water requirements for important crops, such as vegetable crops.

ECONOMIES OF USING AVAILABLE WATERRESOURCES FOR FIELD CROPS IN BEHAIRA GOVERNORATE ON THE LIGHT OF ALTERNATIVE CROP ROTATIONS

The current study aims at identifying water requirements for field crops and water-consuming crops in the light of the current cropping pattern in Behaira Governorate.. the results revealed that costs of water used in the cultivation of rice were the highest reaching about 13.3% of the total costs of production per feddan whereas, the costs of water used in the cultivation of faba bean were the lowest reaching about 5.6% of the total costs of production per feddan in the studied season. Besides, as a result of no water cost paid by farmers, the costs of one unit of water were the lowest for the heavy water-consuming crops whereas, these costs were the highest for the low water-consuming crops even though there were small differences in the total costs of irrigation for these two groups of crops as compared to their water requirements. The results revealed that crop rotation consisting of wheat+maize ranked first in terms of gaining the highest net revenue of water including the irrigation costs of about LE 0.926 per unit of water m3 whereas, the net revenue excluding the irrigation costs for this crop rotation reached about LE 0.789 per unit of water. Nevertheless, the marginal value of water was higher than the costs of irrigation per one feddan cultivate by such crops ranging between about LE 3 thousand per feddan of maize and about LE 800 thousand per feddan cultivated by sesame. On the other hand, the ratio of irrigation costs to the value of marginal product ranged between 73 % for sugar beet and 8% for broad beans. Besides, the net profit for water ranged between 250% for sugar beet and 109 % for broad beans. However, the ratio of the value of marginal product to irrigation costs ranged between 756% for maize and 135 % for sugar beet indicating the high net profit for water as compared to the difference between the value of the marginal product and the costs of irrigation. These results revealed the possibility to increase the costs of irrigation due to the difference between the value of the marginal product and the costs of irrigation. However, this should be put into consideration when applied on the countrywide because these results were obtained from some areas in Bohaira Governorate and these results give an idea about the possibility of increasing the costs of irrigation to gain profits for such important resource. Besides, identifying the economic efficiency for using water resources thus, improving on-farm irrigation.

Irrigation Water Management Practices in Smallholder Vegetable Crops Production: The Case of the Central Rift Valley of Ethiopia

Smallholder irrigated vegetable production in the Central Rift Valley region of Ethiopia is instrumental in ensuring the year-round availability of fresh vegetables in the local market in the country. However, a number of problems constrain irrigated vegetable production in the region. Therefore, asurvey was conducted with the objectives of assessing smallholder irrigated vegetable production practices and identifying factors associated with problems of irrigation water management. The survey was conducted in December 2011. A multistage purposive sampling procedure was employed to select sample districts, peasant associations, and sample respondents that grew vegetables using small-scale irrigation. Key informants were interviewed and group discussions were conducted with smallholder vegetable farmers. Data were collected on household irrigation knowledge, experiences, skills, irrigation water sources as well as on irrigation water management practices such as methods, time, depth and frequency of irrigation. Data were also collected on supplemental irrigation practices under rain-fed vegetable production. In addition, household perceptions on the environmental impacts of irrigation, on-farm irrigation water related challenges, and related information were also recorded. About 16.5% of the respondents indicated that their knowledge and skills on irrigation water management practices were mainly drawn from experiences of trial and error.About 38.1% of the respondents indicated that they irrigated their vegetable fields both in the morning and the afternoon whereas 35.1% replied that they irrigated only in the afternoon. A large number of the respondents (89.6%) replied that they determined irrigation intervals based on specific crop needs. About 90.9% of the respondents replied that they applied enough irrigation water up to the point where the water level reached the furrow basin head. The survey result also indicated that 51.7% of the respondents practiced supplemental irrigation when shortage of moisture occurred in the soil during the rainy season as well at the end of the rainy season. One hundred percent of the respondents replied that they faced problems commonly related with the use of irrigation, namely, soil salinity, waterlogging, soil erosion and degradation, sedimentation, and build-up of pests and diseases. In conclusion, the survey results revealed that extension services on irrigation water management were almost non-existent, and the smallholder vegetable farmers managed irrigation water merely by intuition.Therefore, participatory on-farm irrigation research and extension on irrigation water management practices should be formulated to generate appropriate technologies for enhanced and sustainable irrigated vegetable production in the region.

Water distribution systems and on-farm irrigation practices: limitations and consequences for Afghanistan’s agricultural productivity

The absence of a reliable water supply to farmers is the single most important impediment to food security and agricultural expansion in Afghanistan. Agricultural water supply and distribution systems are reviewed, and a pragmatic strategy is outlined to increase water capital and to better utilize available water. The development and dissemination of on-farm practices that improve water management through community-based approaches represent the best opportunity for improving farmer livelihoods, maintaining social stability and developing a sound agriculture-based economy in the immediate future, independent of the success or failure of national water policies.