Search

An experiment was conducted at CCS Haryana Agricultural University, Hisar during rabi 2010-11 and 2011-12, consisting of three irrigation frequencies viz. one irrigation at CRI, two irrigations at CRI and heading and four irrigations at CRI, late tillering, heading and milking in main plots and five nitrogen levels (0, 50, 100, 150 and 200 kg N/ha) in sub-plots in strip plot design with four replications. Grain yield and NUE increased significantly with increased irrigation levels. Increase irrigation frequency increased the N (33.4 and 31.3%), P (42.2 and 42.3%) and K (26.7 and 25.1%) uptake over one irrigation during 2010-11 and N (16.0 and 15.9%), P (19.4 and 20.7%) and K (11.2 and 13.5%) during 2011-12. Increased nitrogen dose increased the protein content, hectolitre weight, sedimentation value and grain yield over control. Maximum and minimum nutrient uptake was recorded with 200 and 0 kg N/ha. [ABSTRACT FROM AUTHOR]

Droughts and climate change in regions with profitable irrigated agriculture will impact groundwater resources with associated direct and indirect impacts. In the integrated water resource management (IWRM), managed aquifer recharge (MAR) offers efficient solutions to protect, conserve, and ensure survival of aquifers and associated ecosystems, as the Water Framework Directive requires. The purpose of this paper is to analyse the socio-economic feasibility of the MAR system in the overexploited Boquerón aquifer in Hellín (Albacete, Spain) under climate change and varying irrigation demand conditions. To assess, in monetary terms, the profitability of the MAR system, a cost-benefit analysis (CBA) has been carried out. The results for the period 2020-2050 showed that the most favourable situations would be scenarios involving artificial recharge, in which future irrigation demand remains at the present level or falls below 10% of the current irrigation surface, as these scenarios generated an internal rate of return of between 53% and 57%. Additionally, the regeneration of the habitat will take between 5 and 9 years. Thus, the IWRM with artificial recharge will guarantee the sustainability of irrigation of the agricultural lands of Hellín and will achieve water balance even in severe climate change conditions. [ABSTRACT FROM AUTHOR]

A 3-year study was conducted in the Catawba-Wateree River Basin during the spring and summer months of 2009-2011 to evaluate the water savings potential of three smart irrigation controllers compared with standard timer-based irrigation controllers. Thirty-six residential sites, 12 on each of three Duke Energy lakes (Lake Norman, Lake Hickory, and Lake Wylie), were selected for the study. A 3-year study was conducted in the Catawba-Wateree River Basin during the spring and summer months of 2009-2011 to evaluate the water savings potential of three smart irrigation controllers compared with standard timer-based irrigation controllers. Thirty-six residential sites, 12 on each of three Duke Energy lakes (Lake Norman, Lake Hickory, and Lake Wylie), were selected for the study. Each site had an automated, underground irrigation system that directly drew water from the Duke Energy lake that the property bordered. None of the systems had previously been metered and there was no charge to homeowners for withdrawing water from the bordering lake. All sites were instrumented with water meters in 2009 to monitor irrigation water withdrawals, and irrigation system audits were performed before installation of smart technologies. After collecting baseline water-use data in 2009, existing controllers were replaced with one of three smart controllers at 27 of the study sites in 2010, and irrigation was monitored through the end of the 2011 irrigation season. Irrigation treatments included a standard irrigation controller with an add-on soil moisture sensor system (SMS), an evapotranspiration (ET) based controller that received daily reference evapotranspiration estimates from a third-party provider (ET1), an evapotranspiration-based controller with an on-site weather sensor (ET2), and a comparison group that used the existing irrigation controller with no intervention (COMP). Weekly water withdrawals were monitored with on-site data loggers, and turf quality was visually rated and characterized with a normalized difference vegetation index (NDVI) meter. The SMS treatment applied the most irrigation per week (mean of 27.4 mm week-1), compared with 24.7 mm week-1 for the ET1 treatment, and the COMP and ET2 treatments that applied 20.9 and 19.9 mm week-1, respectively. Although applying the most irrigation, the SMS treatment had the greatest effect on water-use behavior for sites receiving technologies, reducing irrigation by 11.7 mm week-1 compared with the baseline year in which the SMS group applied the most water. There was no evidence of a change in water-use behavior in the COMP treatment, but collectively the smart treatments reduced irrigation from 60% more than the gross irrigation requirement (GIR) in 2009 to only 10% more than GIR in 2010 and 2011, without adversely affecting the turf quality. Visual turf quality ratings in the COMP treatment were slightly less than the minimally acceptable level, which may have resulted from underirrigation during high water demand periods. Several challenges to retrofitting existing systems and issues with smart controllers were observed, including poorly designed and maintained existing irrigation systems, incompatibility between existing controllers and SMS sensor modules, failure of all nine soil-moisture sensors, communication failures in ET-based controllers, and manual overrides of smart technologies by study participants. This study emphasizes the importance of proper installation, programming, and maintenance of smart technologies on suitable irrigation systems if they are to function correctly. To maximize water savings, smart irrigation retrofits should be targeted toward systems that historically overirrigate. [ABSTRACT FROM AUTHOR]

Performance indices can be used as indices of energy use in irrigation systems. Pumping stations (PSs) are elements that require energy for irrigation of rice fields by conventional flood irrigation. Interplay of physical, hydraulic, and electrical parameters generates indices that determine the performance in the diagnosis of PSs, operation, and projects for new sets. In this study, it was proposed and classified performance indices for PSs in rice fields, focusing on the efficient use of energy. The study was carried out through an investigation of 160 PSs in operation, located at the western border of Rio Grande do Sul, Brazil, which constituted an actual field situation. Next, PSs were optimized in relation to the selection of a piping system, using the lowest total cost, the choice of pump, and motors with better performance for the necessary situation as criteria. Results provided nine indices that classified the performance as "excellent", "very good", "good", "poor", and "very poor", which allowed the assessment of projects and the diagnosis of PSs. [ABSTRACT FROM AUTHOR]

The saline groundwater irrigation is an important problem in the arid and semiarid region because it can cause soil salinization and reduce crop productivity. The accurate spatial distribution of groundwater salinity can be helpful to managers and decision makers. In this study, the mapping of salinity risk through groundwater electrical conductivity (EC) irrigation was performed based on data collected from 88 wells in the Lower-Cheliff plain (Algeria). The EC data showed a normal distribution based on elementary statistics. The EC classified using Riverside method point out a high risk of groundwater salinity (Class C3) or very high risk (Class C4) for soil salinization. The EC estimated by ordinary kriging method (OK) revealed on one hand, an underprediction of a high value, on the other hand, an overprediction of low value. The methodology of nonparametric and nonlinear of indicator kriging (IK) was performed by three thresholds: EC > 2.25, EC > 3, and EC > 5 dS=m. The map has been obtained from the combination of the local conditional cumulative distribution function (CCDF). The interpolated map by IK indicates the same overall spatial distribution of salinity with the one obtained by OK, enlightening differences in the shape and size of the area. The comparison between the groundwater EC estimated by OK and the one using IK demonstrates that IK has a better spatial prediction of salinity in terms of area and uncertainty. The groundwater salinity map was improved and accurately predicted by IK interpolation method. [ABSTRACT FROM AUTHOR]

In pressurized irrigation systems the total long-term costs can often be minimized by dividing the pipeline into segments of different diameters. To properly design such a system requires an accurate hydraulic analysis. In this study, an analytical procedure was developed to simulate the energy grade line along trickle laterals with dual pipe sizes. Appropriate equations were developed to accurately estimate several important design factors such as the total head loss (JTot), the total required head at the inlet (Ein) and the minimum pressure head along the lateral (Emin). The methodology takes into account the effect of the number of outlets along each reach of the lateral, outflow nonuniformity, friction factor variation, velocity head changes, and local losses. Friction losses were evaluated using the power form equation of the Darcy-Weisbach formula. Local losses and velocity head change were both addressed by obtaining an average along the lateral constant coefficient which is a function of the number of outlets and the outflow at the downstream end of each reach. Two power functions were also used to estimate the outflow nonuniformity along each segment of the lateral. The accuracy of the proposed method is very high in all cases examined and the results tend to accurately follow the numerical stepwise solution. Assuming a uniform outflow for the proposed method results in accurate estimations of Ein and Emin but generally not of JTot. The nonuniform outflow approach, on the other hand, calculates all three design parameters with a high degree of accuracy. [ABSTRACT FROM AUTHOR]

It has been well documented in specialized literature that, under certain circumstances, the Clément's first demand formula fails in estimating flow in water distribution networks. Through numerical examples, the authors show that the method fails when the number of hydrants supplied by a pipe is small or when the nominal flow rate of the hydrants is nonhomogeneous. In such cases, the normality hypothesis of the design flow rate random variable, an assumption needed by Clément's formula, cannot be made. An alternative method for calculating the design flow rate as a nonnormal random variable is presented. The method works very well in all analyzed examples, mainly because the normality hypothesis is not required. The paper also provides a free-software R-script using freely available software that allows applying the proposed method to user-defined cases. The script helps to understand the method's theoretical basis and can be used as a tool for checking the assumption of normality of data. Therefore, the program allows the applicability of Clément's method to be checked and provides an alternative accurate solution. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the effect of different irrigation depths on the yield, water use efficiency (WUE), and yield response factor (Ky) of carrot (cv. 'Brasília') in the edaphoclimatic conditions of Baixada Fluminense, RJ, Brazil. Field trials were conducted in a Red-Yellow Argisol in the 2010-2011 period. A randomized block design was used, with 5 treatments (depths) and 4 replicates. Depths were applied by drippers with different flow rates, and the irrigation was managed by time domain reflectometry (TDR) technique. The reference (ETo) and crop (ETc) evapotranspiration depths reached 286.3 and 264.1mm in 2010, and 336.0 and 329.9mm in 2011, respectively. The root yield varied from 30.4 to 68.9t ha-1 as a response to treatments without irrigation and 100% replacement of the soil water depth, respectively. Values for WUE in the carrot crop varied from 15 to 31kg m-3 and the mean Ky value was 0.82. The mean values for Kc were obtained in the initial (0.76), intermediate (1.02), and final (0.96) stages. Carrot crop was influenced by different water depths (treatments) applied, and the highest value for WUE was obtained for 63.4% of soil water replacement. [ABSTRACT FROM AUTHOR]

Side weirs are used to divert the flow from a main channel to a desired environmental area. These basic hydraulic elements are commonly preferred in drainage and irrigation systems of surface water. Many studies have been conducted to determine the outflow discharge of side weirs. De Marchi's approach, which assumes constant specific energy along the side weir, can be applied to describe the surface equation and therefore the discharge coefficient. However, the use of this approach is not easy in experimental and theoretical studies. This study presents a new semianalytical approach that determines the discharge capacity of rectangular side weirs. The findings of this new method are consistent with numerical and experimental results. [ABSTRACT FROM AUTHOR]

The present study was carried out in order to evaluate the effects of irrigation depths applied through drip and presence/ absence of soil cover in onion yield, under agroecological farming. The experiment was conducted in Seropédica, RJ, Brazil, from May to September 2012. The experimental design was a randomized complete block with split-plot design with 10 treatments and 7 replications, characterized by the presence (+S) and absence (-S) of soil cover and five irrigation depths according to percentages of the crop evapotranspiration (ETc): 0, 22, 45, 75 and 100% (0, 155, 220.6, 320.5 and 372,7mm in +S condition and 0, 145.5, 207.6, 285, 351,4mm in -S condition). The irrigation influenced by second-order polynomial regression the total yield of bulbs, percentage distribution of bulbs in diameter classes and water use efficiency (WUE) in the -S condition, and in the linear regression the WUE in +S condition. The soil cover promoted an increase on the total bulb yield, WUE and the percentage of bulbs classified in classes of greater diameter. [ABSTRACT FROM AUTHOR]

The main purpose of this study is to develop an easy-to-use weather generator (WG) for the downscaling of gridded data to point measurements at regional scale. The WG is applied to daily averaged temperatures and annual growing degree days (GDD) of wheat. This particular choice of variables is motivated by future investigations on temperature impacts as the most important climate variable for wheat cultivation under irrigation in Iran. The proposed statistical downscaling relates large-scale ERA-40 reanalysis to local daily temperature and annual GDD. Long-term local observations in Iran are used at 16 synoptic stations from 1961 to 2001, which is the common period with ERA-40 data. We perform downscaling using two approaches: the first is a linear regression model that uses the ERA-40 fingerprints (FP) defined by the squared correlation with local variability, and the second employs a linear multiple regression (MR) analysis to relate the large-scale information at the neighboring grid points to the station data. Extending the usual downscaling, we implement a WG providing uncertainty information and realizations of the local temperatures and GDD by adding a Gaussian random noise. ERA-40 reanalysis well represents the local daily temperature as well as the annual GDD variability. For 2-m temperature, the FPs are more localized during the warm compared with the cold season. While MR is slightly superior for daily temperature time series, FP seems to perform best for annual GDD. We further assess the quality of the WGs applying probabilistic verification scores like the continuous ranked probability score (CRPS) and the respective skill score. They clearly demonstrate the superiority of WGs compared with a deterministic downscaling. [ABSTRACT FROM AUTHOR]

Historic results of perennial ryegrass ( Lolium perenne L.) breeding include improved disease resistance, biomass, and nutritional quality. Yet, lack of tolerance to water stress limits its wide use. Recent efforts to increase water soluble carbohydrate (WSC) content in perennial ryegrass may increase drought tolerance. Herein, we report results of a multi-year and location evaluation of differing precipitation/irrigations levels on genetic and genotype × environment interaction effects of various agronomic traits in perennial ryegrass. The study included two UK environments (Aberystwyth, Wales and Edinburgh, Scotland) and four USA environments located in Logan, UT and consisting in four supplemental irrigation levels in a line-source irrigation design. Data included herbage dry matter, dry matter digestibility, crude protein, and WSC, collected from 2011 to 2013. There were differences ( P < 0.05) among the included cultivars for each phenotype when evaluated across environments. There was observed cultivar × environment interaction for each phenotype, which precluded the identification of the best cultivar over all environments. Additive main effect and multiplicative interaction modeling allowed for grouping of the individual environments to mega-environments. The analysis identified three mega-environments for each phenotype: (1) the UK environments, (2) the two highest Logan irrigation levels, and (3) the two lowest Logan irrigation levels. Mega-environments designations corresponded to water stress, temperature, and inherent geographic/climate differences between the environments. The evidence for the potential of increased WSC to improve drought tolerance under water stress was inconclusive, but high WSC cultivars also exhibited high herbage production under the imposed water stress. [ABSTRACT FROM AUTHOR]

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

Spatial surface soil moisture can be an important indicator of crop conditions on farmland, but its continuous estimation remains challenging due to coarse spatial and temporal resolution of existing remotely-sensed products. Furthermore, while preceding research on soil moisture using remote sensing (surface energy balance, weather parameters, and vegetation indices) has demonstrated a relationship between these factors and soil moisture, practical continuous spatial quantification of the latter is still unavailable for use in water and agricultural management. In this study, a methodology is presented to estimate volumetric surface soil moisture by statistical selection from potential predictors that include vegetation indices and energy balance products derived from satellite (Landsat) imagery and weather data as identified in scientific literature. This methodology employs a statistical learning machine called a Relevance Vector Machine (RVM) to identify and relate the potential predictors to soil moisture by means of stratified cross-validation and forward variable selection. Surface soil moisture measurements from irrigated agricultural fields in Central Utah in the 2012 irrigation season were used, along with weather data, Landsat vegetation indices, and energy balance products. The methodology, data collection, processing, and estimation accuracy are presented and discussed. [ABSTRACT FROM AUTHOR]

Wadi aquifers in Saudi Arabia historically have been recharged primarily by channel loss (infiltration) during floods. Historically, seasonal groundwater levels fluctuated from land surface to about 3 m below the surface. Agricultural irrigation pumping has lowered the water table up to 35 m below the surface. The geology surrounding the fluvial system at Wadi Qidayd consists of pelitic Precambrian rocks that contribute sediments ranging in size from mud to boulders to the alluvium. Sediments within the wadi channel consist of fining upward, downstream-dipping beds, causing channel floodwaters to pass through several sediment sequences, including several mud layers, before it can reach the water table. Investigation of the wadi aquifer using field observation, geological characterization, water-level monitoring, geophysical profiles, and a hypothetical model suggests a critical water level has been reached that affects the recharge of the aquifer. The wetted front can no longer reach the water table due to the water uptake in the wetting process, downstream deflection by the clay layers, and re-emergence of water at the surface with subsequent direct and diffusive evaporative loss, and likely uptake by deep-rooted acacia trees. In many areas of the wadi system, recharge can now occur only along the channel perimeter via fractured rocks that are in direct horizontal hydraulic connection to the permeable beds above and below the water table. [ABSTRACT FROM AUTHOR]

Chlorophyll is a natural coloring extract used extensively in the food and pharmaceutical industries. In Europe, most chlorophyll is produced commercially from rainfed grassland production in eastern England. This paper describes a biogeochemical modeling study to assess the potential yield benefits associated with switching from rainfed to irrigated production. The research is in response the impacts of recent summer droughts on yield coupled with risks regarding climate change, rainfall reliability and long-term viability of rainfed production. The Denitrification-Decomposition model was calibrated and validated using multiple field data ( n = 47) from 2000 to 2009 for a tall fescue grass ( Festuca arundinacea) to simulate a range of irrigation and fertilizer management regimes on yield (annual and individual yield per cut). For chlorophyll production, a schedule combining 300 mm year−1 irrigation with 300 kg N ha−1 was shown to provide the highest average yield (an uplift of +62% above current levels). Switching from rainfed to irrigated production could also potentially halve (54%) current levels of fertilizer application. The implications for reducing environmental impacts from nitrate leaching are discussed. [ABSTRACT FROM AUTHOR]

The indigenous forage species such as Buffel grass ( Cenchrus ciliaris) are capable of surviving with less water than most introduced species such as Rhodes grass ( Chloris gayana) and alfalfa. However, the productivity of Buffel grass as a function of the amount of water applied is unknown. A case study was conducted in Oman to evaluate the response of Buffel and Rhodes grasses to different irrigation levels using line-source sprinkler irrigation system. Four irrigation treatments (40, 65, 100 and 125%) based on reference evapotranspiration (ETo) with two grass species (Buffel and Rhodes grasses) were investigated as sub-main treatments in strip plot design with four replications. The average total amount of applied water during the study period were 15 126, 24 580, 37 815 and 47 269 m3 ha−1, for the four irrigation treatments, respectively. The results of 12 cuts during 514 days indicated that Buffel grass has significantly higher dry weight production (DW) and water productivity than Rhodes grass at all irrigation levels. Irrigation by 65% of ETo for Buffel grass has the highest water productivity value reached to 0.95 kg m−3 and 42% of applied water can be saved to produce the same amount of DW of Rhodes grass. Soil salinity increased in the soil profile for 40, 65 and 100% ETo irrigation levels during the summer season and the soil salinity values were higher at Rhodes than Buffel grasses location for these irrigation levels. [ABSTRACT FROM AUTHOR]

Air is squeezed out of the soil in the process of traditional irrigation. Hypoxia stress of the root zone is harmful to the yield and quality of crops. It was found that the improvement of the soil oxygen condition can increase the crop yield and quality in the root zone. In recent years, a number of studies showed that hypoxia stress has bad influence on root zone, and the ventilation technologies have some positive effects on crop yield and quality. This paper introduces and analyzes the mechanism of hypoxia stress in root zone, and provides an overview about characteristics and application on airjection irrigation. Simultaneously, the advantages and disadvantages of different airjection irrigation technologies were investigated, the achievements that have been made in this filed were summarized, and some existed problems were discussed. Based on the previous studies, the research trends of the airjection irrigation technology were proposed, which can provide a reference for the further research in the research field. [ABSTRACT FROM AUTHOR]

Farmers in Pakistan either rely only on groundwater or manage conjunctive use of surface and groundwater for irrigating crops due to shortage of canal water. Present study was undertaken to find variations in conjunctive water management practices, groundwater productivity and crop profitability in Chuharkana irrigation sub-division in Punjab. Physical and questionnaire based data were collected from 120 farmers using stratified random sampling technique from vicinity of four watercourses of Lagar distributary. Trajectory method was employed to measure tubewells' discharge for evaluating groundwater productivity across watercourse reaches. EC, SAR and RSC were measured to evaluate groundwater quality. Results show prevalence of surface and groundwater use for irrigation. Area under conjunctive use decreased from 76.6% at head to 46% at tail due to decreased canal water supply towards tail while area irrigated by groundwater-only increased from 20% to 54% across head to tail. Analysis of groundwater samples showed lower quality levels. EC, SAR and RSC ranged between 1.27-1.55 dS m-1, 6.39-9.54 (mmol L-1)1/2 and 3.75-4.18 meL-1 respectively, with higher values towards tail. Groundwater productivity for wheat was relatively higher at the head, while that of rice did not vary much across watercourse reaches. Conducive soil conditions and more reliance on groundwater for timely irrigation resulted gross margins at the tail. [ABSTRACT FROM AUTHOR]

Agriculture of arid and semi-arid regions is effected by over extraction of groundwater (GW) around the world especially in the developing countries like Pakistan. Groundwater (GW) should be properly recharged to overcome the issue of declining water levels. Analysis of GW use against recharge is done to address the issues of sustainable management and aquifer mining in Hakra branch canal system off-taking Eastern Sadiqia canal of Pakistan. Various water balance components were computed to estimate the net recharge using modeling as well as with remote sensing techniques. Soil profile data, water table depths, canals off take discharges and all the climatic data for the year 2006-11 were used as input data sets in Soil and Water Assessment Tool (SWAT) to compute GW recharge. Hakra branch canal system is divided into 17 off-taking distributaries and direct water courses. The SWAT model is calibrated and validated using in situ extents of soil, vegetation, evapotranspiration and surface supplies. Nash-Sutcliffe Efficiency (NSE) and coefficient of determination (R²) were used as statistical parameters for calibration and validation of results. Using the net recharge, net GW abstraction was calculated for entire command area of Hakra branch canal system. SWAT was calibrated (NSE = 0.97, R² = 0.87) for the period of 2006-08 and validated (NSE = 0.98, R² = 0.90) for the period 2009-11. Average net recharge to the GW aquifer for the whole command area is estimated at -91 mm yr-1, indicating abstraction is greater than recharge from all sources. Whereas, average net GW abstraction is calculated as 712 mm yr-1 in the study area. The GW abstraction trend is increasing in the tail distributaries due to less canal water supplies. It is recommended to increase the head discharge of the main canal and share of the tail distributaries. [ABSTRACT FROM AUTHOR]

Pakistan is facing a shortage of water for many years, mainly due to increase in population and mismanagement of available water resources. There is average annual potential of 23 billion m³ in hill torrent water resources of the country, which has not yet been utilized to its productive potential. This study compared the irrigation practices, crop yield, water productivity and benefit cost ratio of spate irrigated crops with other available sources of irrigation in Mithawan hill torrent command area of Dera Ghazi Khan, Pakistan. The data were collected through field visits/observations, farmers' interviews, and from the relevant organizations. CROPWAT model was used to determine crops water requirements for assessment of irrigation efficiencies while SPSS software was used for descriptive statistics of the study data. The cropping intensities in the study area during wet and dry years were 90 and 70%, respectively, with an average of 80%. The spate irrigated fields were applied 1.05m depth of water at once in a season that had an average application efficiency of 28% whereas, the efficiency of canal water and groundwater applied separately or conjunctively varied from 24 to 86% with an average of 52%. The water productivity of spate irrigated crops varied from 0.08 to 0.19kg/m³ while canal water and/or groundwater irrigated crops cultivated in the study area varied from 0.27 to 3.28kg/m³. Normally, cotton was cultivated with canal water and onion with groundwater that had water productivity of 0.27 and 3.28kg/m³, respectively. The benefit cost ratio of spate irrigated crops varied from 1.49 to 2.39, while for irrigated with canal water and/or groundwater it varied from 1.29 to 1.57. Based on the result of this study, it may be concluded that the efficient utilization of hill torrents for spate irrigation would improve the copping intensities, crop yield, water productivity and socioeconomic conditions of the farmers of study area. Also, the efficient utilization of hill torrent water for spate irrigation would minimize the dependence on canal water and groundwater in the study area. [ABSTRACT FROM AUTHOR]

In the current scenario of worldwide limited water supplies, conserving water is a major concern in agricultural areas. Characterizing within-orchard spatial heterogeneity in water requirements would assist in improving irrigation water use efficiency and conserve water. The crop water stress index (CWSI) has been successfully used as a crop water status indicator in several fruit tree species. In this study, the CWSI was developed in three Prunus persica L. cultivars at different phenological stages of the 2012 to 2014 growing seasons, using canopy temperature measurements of well-watered trees. The CWSI was then remotely estimated using high-resolution thermal imagery acquired from an airborne platform and related to leaf water potential (ΨL) throughout the season. The feasibility of mapping within-orchard spatial variability of ΨL from thermal imagery was also explored. Results indicated that CWSI can be calculated using a common non-water-stressed baseline (NWSB), upper and lower limits for the entire growing season and for the three studied cultivars. Nevertheless, a phenological effect was detected in the CWSI vs. ΨL relationships. For a specific given CWSI value, ΨL was more negative as the crop developed. This different seasonal response followed the same trend for the three studied cultivars. The approach presented in this study demonstrated that CWSI is a feasible method to assess the spatial variability of tree water status in heterogeneous orchards, and to derive ΨL maps throughout a complete growing season. A sensitivity analysis of varying pixel size showed that a pixel size of 0.8 m or less was needed for precise ΨL mapping of peach and nectarine orchards with a tree crown area between 3.0 to 5.0 m². [ABSTRACT FROM AUTHOR]

The success or failure of operating a rainwater harvesting system (RWH) depends on both technological and non-technological factors. The importance of non-technological factors in attaining sustainable RWH operation is rarely emphasized. This study aims to assess the contribution of non-technological factors through determining decisive factors involved in the use of RWHs for agriculture irrigation in Beijing. The RWHs for agriculture irrigation in Beijing are not operating as well as expected. If the decisive factors are identified to be non-technological, the significance of non-technological factors will be highlighted. Firstly, 10 impact factors comprising non-technological and technological factors are selected according to both a literature review and interviews with RWH managers. Following this, through an artificial data mining method, rough set analysis, the decisive factors are identified. Results show that two non-technological factors, "doubts about rainwater quality" and "the availability of groundwater" determine whether these systems will continue or cease RWH operation in Beijing. It is, thus, considered necessary to improve public confidence in and motivation on using rainwater for agriculture irrigation, as this is the main obstacle in the sustainable and successful operation of RWHs. Through a case study of RWHs in Beijing, the study verifies the importance of acknowledging non-technological factors to achieve sustainable water management and considers that such factors should receive more attention by decision makers and researchers. [ABSTRACT FROM AUTHOR]

Irrigation is a widely used water management practice that is often poorly parameterized in land surface and climate models. Previous studies have addressed this issue via use of irrigation area, applied water inventory data, or soil moisture content. These approaches have a variety of drawbacks including data latency, accurately prescribing irrigation intensity, and a lack of conservation of water volume for models using a prescribed soil moisture approach. In this study, we parameterize irrigation fluxes using satellite observations of evapotranspiration (ET) compared to ET from a suite of land surface models without irrigation. We then incorporate the irrigation flux into the Community Land Model (CLM) and use a systematic trial-and-error procedure to determine the ground- and surface-water withdrawals that are necessary to balance the new irrigation flux. The resulting CLM simulation with irrigation produces ET that matches the magnitude and seasonality of observed satellite ET well, with a mean difference of 6.3 mm month-1 and a correlation of 0.95. Differences between the new CLM ET values and satellite-observed ET values are always less than 30 mm month-1 and the differences show no pattern with respect to seasonality. The results reinforce the importance of accurately parameterizing anthropogenic hydrologic fluxes into land surface and climate models to assess environmental change under current and future climates and land management regimes. [ABSTRACT FROM AUTHOR]

Generic land surface models are generally driven by large-scale data sets to describe the climate, the soil properties, the vegetation dynamic and the cropland management (irrigation). This paper investigates the uncertainties in these drivers and their impacts on the evapotranspiration (ET) simulated from the Interactions between Soil, Biosphere, and Atmosphere (ISBA-A-gs) land surface model over a 12-year Mediterranean crop succession. We evaluate the forcing data sets used in the standard implementation of ISBA over France where the model is driven by the SAFRAN (Système d'Analyse Fournissant des Renseignements Adaptés à la Nivologie) high spatial resolution atmospheric reanalysis, the leaf area index (LAI) time courses derived from the ECOCLIMAP-II land surface parameter database and the soil texture derived from the French soil database. For climate, we focus on the radiations and rainfall variables and we test additional data sets which include the ERA-Interim (ERA-I) low spatial resolution reanalysis, the Global Precipitation Climatology Centre data set (GPCC) and the MeteoSat Second Generation (MSG) satellite estimate of downwelling shortwave radiations. The evaluation of the drivers indicates very low bias in daily downwelling shortwave radiation for ERA-I (2.5Wm-2) ompared to the negative biases found for SAFRAN (-10Wm-2) and the MSG satellite (-12 Wm-2). Both SAFRAN and ERA-I underestimate downwelling longwave radiations by -12 and -16 Wm-2 respectively. The SAFRAN and ERA-I/GPCC rainfall are slightly biased at daily and longer timescales (1 and 0.5% of the mean rainfall measurement). The SAFRAN rainfall is more precise than the ERA-I/GPCC estimate which shows larger inter-annual variability in yearly rainfall error (up to 100 mm). The ECOCLIMAP-II LAI climatology does not properly resolve Mediterranean crop phenology and underestimates the bare soil period which leads to an overall overestimation of LAI over the crop succession. The simulation of irrigation by the model provides an accurate irrigation amount over the crop cycle but the timing of irrigation occurrences is frequently unrealistic. Errors in the soil hydrodynamic parameters and the lack of irrigation in the simulation have the largest influence on ET compared to uncertainties in the large-scale climate reanalysis and the LAI climatology. Among climate variables, the errors in yearly ET are mainly related to the errors in yearly rainfall. The underestimation of the available water capacity and the soil hydraulic diffusivity induce a large underestimation of ET over 12 years. The underestimation of radiations by the reanalyses and the absence of irrigation in the simulation lead to the underestimation of ET while the overall overestimation of LAI by the ECOCLIMAP-II climatology induces an overestimation of ET over 12 years. This work shows that the key challenges to monitor the water balance of cropland at regional scale concern the representation of the spatial distribution of the soil hydrodynamic parameters, the variability of the irrigation practices, the seasonal and inter-annual dynamics of vegetation and the spatiotemporal heterogeneity of rainfall. [ABSTRACT FROM AUTHOR]

The house rat (Rattus rattus) of the order 'rodentia' and family 'muridae', is one of the major vertebrate pests of agriculture and stored grains, inhabiting the main agro-ecosystems of the world. In Pakistan, damage has also been reported on a variety of economically important crops and stored grains. In an agricultural complex of University of Agriculture, Faisalabad comprising the canal irrigated plantations, infestations of house rat was assessed under the controlled and treated (trap barrier) situation for the mature stage of rice (Oryza sativa L.), to assess the inhibited damage. Seemingly, for the one acre control plot, house rat depredations remained high (16.27±0.49), while in the trap barrier phase, there was a considerable decline (2.89±0.24) with respect to the rat damage. Average trap success ratios (TSRs) in the unprotected conditions, were fairly intensive (101.67±3.06), but were significantly reduced (18.08±1.47) in the trap barrier applied rice plot. The present results indicated that, implications of ecologically based rodent management strategies provided dividends on a small landscape, but may also be beneficial over multiple cropping systems, on both agricultural and horticultural food sources, not only throughout the region of Central Punjab, but also over throughout Pakistan, to maintain crop sustainability, without serious impacts on the productivity of agro-ecosystems. [ABSTRACT FROM AUTHOR]

In Pakistan, there is dire need to enhance productivity by proper use of underutilized lands through improved agricultural practices/irrigation methods. Study was conducted in the command area of Killianwala distributary to check the impact of raised bed planting for improving productivity potential of underutilized lands. Information regarding area under wheat crop and fallow lands in each village was explored using GIS. Fallow lands in 19,911 ha of Culturable Command Area (CCA) were estimated to be 520 ha, while the remaining cultivated lands were also found to be underutilized in terms of low productivity potential. Reasons found for the lands underutilization were water shortage, salinity and land preparation requirements, with water shortage as major problem along the whole length of distributary. Wheat was planted on raised beds as well as by conventional method at seven sites and average yield increase and water saving of 18% and 49%, respectively, was recorded for wheat under raised bed planting. It was estimated that replacement of conventional sowing method by raised bed planting in the study area can enhance the production of wheat by 10.44 thousand tons, while the achievement of about 50% water saving will also help bringing fallow lands under cultivation, thus giving further boost to production at regional scale. [ABSTRACT FROM AUTHOR]

Eggplant (Solanum melongena L.) is an increasingly popular crop in the United States. In the southeastern United States, eggplant is often produced with high levels of irrigation water [above the rate of crop evapotranspiration (ETc)], resulting in water waste and nitrogen (N) leaching. The objective of this research was to assess the effects of irrigation rate on plant growth and fruit yield in eggplant. The study was conducted in Tifton, GA, in the fall of 2010 and 2011. Eggplant plants cv. Santana were grown on raised beds (1.8 m centers) covered with white plastic film mulch. There was a single drip tape along the center of the bed. The design was a randomized complete block with five treatments and four replications. Treatments consisted of irrigation rates based on ETc (33%, 67%, 100%, 133%, and 167% ETc). Plant growth, chlorophyll index (Cl), and volumetric soil water content (SWC) were monitored over the season. In 2010, SWC (0-30 cm deep) increased and soil nitrate levels decreased with increasing irrigation rates. Foliar N and potassium (K), and Cl decreased with increasing irrigation rate, probably due to a dilution effect. Stem diameter, leaf dry weight (DW), and vegetative top DW increased with increasing irrigation rate. Net photosynthesis and stomatal conductance (gs) were lowest at 33% ETc. Fruit number and fruit yields (marketable and total) were also lowest at 33% ETc and there were little yield differences among irrigation rates higher than 33% ETc. In 2011, irrigation rate had minor or no effect on SWC, plant growth of mature plants, leaf gas exchange, and fruit number and yield. The no treatment effect observed for eggplant in 2011 was likely because study was conducted in a low field that remained moist most of the time, nullifying the treatment effects. Results suggested that eggplant may tolerate mild water stress, since plants irrigated at 67% ETc produced fruit yields similar to those of plants irrigated at 100% ETc or higher rates. Thus, there is a potential to save water by reducing current irrigation rates without negatively impacting fruit yields. [ABSTRACT FROM AUTHOR]

Trials were conducted in 2011 and 2012 with 'Aristotle' bell pepper (Capsicum annuum L.) grown under different tillage methods and irrigation regimes in organically and conventionally managed production systems. Treatments consisted of strip tillage or plastic mulch in well-watered or water-restricted irrigation regimes. Within organic and conventional production systems, the study was arranged as a split-plot randomized block design with strip tillage or plastic mulch as the main plot and irrigation regime as subplot. Leaf water potential (ψL), soil penetration resistance (compaction), volumetric water content (VWC), soil temperature, and pepper yield were measured. Soil VWC was greater in strip-tillage plots compared with plastic mulch plots under both well-watered and water-restricted conditions for plots in the organic system in 2011 and conventional system in 2012. In addition, soil VWC was numerically lower, if not always statistically different, in water-restricted plots compared with well-watered plots. The trend of soil temperatures within each production system were similar in 2011 and 2012, with plastic mulch plots having slightly higher soil temperatures than strip tillage, despite using white-on-black plastic mulch. Midday ψL was affected by water regime, with well-watered plants having a significantly lower ψLl than water-restricted plants; however, there were no effects of irrigation on predawn ψL. Tillage method and sampling location (between row and within row) significantly interacted to affect soil penetration resistance in 2011 and 2012. There was a significant interaction of tillage by irrigation regime on yield within conventional systems in both years, but not in organically managed plots. In 2011, yield data also indicated that the date at which 50% of marketable fruit were harvested (yield_mid) were later for strip-tillage-grown plants than plastic mulch-treated plants within conventional and organic production systems, respectively. [ABSTRACT FROM AUTHOR]

This paper aims to address the issue of income distribution among farm households growing cotton under the irrigated conditions of the Harran Plain located in the Sanliurfa Province. Comparing the results from ex-ante and ex-post distributional analyses, it is possible to determine the socio-economic impacts of the South Eastern Anatolia (GAP) Project on the well-being of these local cotton farmers. Results show that although in absolute terms the provision of Harran Plain irrigation projects has increased income of local cotton farmers, Gini ratio of 0.49 indicates that there has been uneven income distribution in the Harran Plain's cotton sector. The most important factor affecting income distribution is determined to be how well or poor land under cotton is distributed among these local farmers. [ABSTRACT FROM AUTHOR]

Biophysical and social systems are linked to form social-ecological systems whose sustainability depends on their capacity to absorb uncertainty and cope with disturbances. In this study, we explored the key biophysical and socio-cultural factors underlying ecosystem service supply in two semiarid watersheds of southern Spain. These included variables associated with the role that freshwater flows and biodiversity play in securing the system's capacity to sustain essential ecosystem services and their relationship with social demand for services, local water governance, and land-use intensification. Our results reveal the importance of considering the invisible dimensions of water and biodiversity, i.e. green freshwater flows and trait-based indicators, because of their relevance to the supply of ecosystem services. Furthermore, they uncover the importance of traditional irrigation canals, a local water governance system, in maintaining the ecosystems' capacity to supply services. The study also highlights the complex trade-offs that occur because of the spatial mismatch between ecosystem service supply (upstream) and ecosystem service demand (downstream) in watersheds. Finally, we found that land-use intensification generally resulted in losses of the biophysical factors that underpin the supply of some ecosystem services, increases in social demand for less diversified services, and the abandonment of local governance practices. Attempts to manage social-ecological systems toward sustainability at the local scale should identify the key biophysical and socio-cultural factors that are essential for maintaining ecosystem services and should recognize existing interrelationships between them. Land-use management should also take into account ecosystem service trade-offs and the consequences resulting from land-use intensification. [ABSTRACT FROM AUTHOR]

Meliorations and their specific forms - irrigations - are one of the forms of anthropopressure within geoecosystems. The research studies conducted within the Parsęta basin focused on the sub-irrigation (seepage irrigation) systems formed in the 19th century. Query of archive materials and maps, hydrochemical and phytosociological terrain mapping and laboratory testing of water samples collected were used in the studies. In the study area were found the remains of the thirty old irrigation systems, which together occupy 2% of the Parsęta basin area. For many years most of them have not fulfilled their primary economic functions. Still, these systems have an impact on the cycle of waters and have become an important factor in increasing the geo- and biodiversity within the postglacial landscape. By expanding a range of wetland riparian areas, they fulfil relevant functions to protect surface waters against the supply of biogenic components. Some of them could be used to enlarge wetlands and floodplains within river valleys. [ABSTRACT FROM AUTHOR]

The present work was conducted to assess the physico-chemical parameters of Tsada Agam River found in Mekelle, Tigray, Ethiopia and determine its suitability for domestic and irrigation purposes. Water samples were collected monthly for two consecutive months (February to March, 2013) at four sampling sites and analyzed for various physico-chemical parameters. The study indicated that the mean value of studied parameters, except electrical conductivity, total dissolved solids, turbidity, total alkalinity, calcium ion, sulphate ion, and total phosphorus of the river water samples were within the permissible limit of WHO for drinking water. The findings also showed the mean value of studied parameters, except sulphate ion concentration, were within the permissible limit of FAO for irrigation water. Therefore, the river water was found to be unfit for human consumption and was found to be safe and utilizable for irrigation purposes. If the quality management was properly maintained, the Tsaeda Agam River water could be utilized for a wide range of applications such as drinking and irrigation. [ABSTRACT FROM AUTHOR]

The implementation of community-based approach, where community can control a government owned infrastructure project, is rarely found. However, Sumatra River Basin Organization (BWSS) V successfully implemented a small scale irrigation project using this method in West Sumatra Province, Indonesia. This paper aims to describe how this policy was implemented, highlight its milestones, and discuss the advantages of its application. A detailed literature review and semi structured interviews were conducted to achieve the objectives. It was found that the implementation of community-based approach can bring about a sense of belonging, sustainability, and a source of income for the community. Hence, the project was finished on time within budget with high quality materials. In some cases the quantity of the project was more than it was targeted. The key policy that contributed to the success was trusting community to control the project and making sure that the proposed project came from the community. [ABSTRACT FROM AUTHOR]

An innovative approach for artificial soil construction is briefly characterized, and its basic principles are given. The major kinds of soil constructions and materials used for their creation are discussed. Quantitative aspects of the formation of layered soil constructions for irrigation farming and greening of urban areas under high anthropogenic loads are examined. Technological design of these constructions is based on modeling energy and mass fluxes in soil systems with the use of HYDRUS-1D software. Technological approaches for the application of biopolymer materials into different soil layers with the aim to increase the soil water capacity, protect the soils from secondary salinization and contamination with water-soluble pollutants, and improve the resistance of these materials toward biological destruction are discussed. The tests of the layered soil constructions in some countries of the Persian Gulf and in Moscow have proved their high efficiency. The productivity of green plantations can be increased by 1.5-2 times owing to the increased efficiency of water consumption and protection of the root zone from soluble salts under conditions of the natural or technogenic salinization (contamination) and deficit of precipitation. [ABSTRACT FROM AUTHOR]

The limited availability of water at low prices and the current scheme for specific supply arrangements (SSA/REA), both determined at the political level, explain that the goal of being self-sufficient in terms of forage consumption is currently unattainable in the Canaries. The "PFORCA" Plan aims to counteract this reality and increase their level of self-sufficiency. The financial aid relating to the REA reduces the amount payable for the imported fodder (annual 83,000 t) versus local product, which influences the decision making by farmers. According to calculations, performed by reusing the water instead of discharging, Maralfalfa production could be competitive against imports, being financially viable with water prices in a range of 0.20-0.30 €/m3 (prices perfectly acceptable for reclaimed water with low levels of treatment, but fulfilling requirements reuse of Spanish law, RD 1620/2007). The economic contribution of forage crops could represent the creation of 640 new jobs, the enhancement of land currently abandoned, plus an increase in Gross Domestic Product (GDP) of the archipelago on more than 23 million € (M€), product of the substitution of imports by local production. Also, it would help to save the REA's aid (6 M€). [ABSTRACT FROM AUTHOR]

Excessive irrigation and leaching are of increasing concern in container plant production. It can also necessitate multiple fertilizer applications, which is costly for growers. Our objective was to determine whether fertilizer and irrigation water can be applied more efficiently to reduce leachate volume and nutrient content without negatively impacting aboveground growth of Gardenia jasminoides 'MAGDA I'. Plants were fertilized with one of three rates of a controlled-release fertilizer (subplots) (Florikan 18-6-8,9-10 month release; 18.0N-2.6P-6.6K) [100 (40 g/plant), 50 (20 g/plant), and 25% of bag rate (10 g/plant)| and grown in 5.4-L containers outside for 137 days. Soil moisture sensor-controlled, automated irrigation was used to provide plants with one of four irrigation volumes (whole plots) (66, 100, 132, or 165 mL) at each irrigation event. All plants were irrigated when the control treatment (66 mL irrigation volume, 100% fertilizer treatment) reached a volumetric water content (VWC) of 0.35 m³⋅m-3. Plants in the different irrigation treatments were irrigated for 2,3,4, or 5 minutes, thus applying 66,100,132, or 165 mL/plant in the different irrigation treatments. Fertilizer rate had a greater effect on aboveground growth than irrigation volume with the 25% fertilizer rate resulting in significantly lower shoot dry weight (18.7 g/plant) than the 50% and 100% rates (25.3 and 27.3 g/plant respectively). Growth index was also lowest in the 25% fertilizer rate. Leachate volume varied greatly during the growing season due to rainfall and irrigation volume effects on leachate were most evident during the third, eighth, and ninth biweekly leachate collections, during which there was minimal or no rainfall. For these collections the control treatment of 66 mL resulted in minimal leachate (less than 130 mL over the 2-week leachate collection period), whereas leachate volume increased with increasing irrigation volumes. Pore water electrical conductivity (EC), leachate EC, NO3-N content, and PO4-P content were all highest with the 100% fertilizer rate, with the 66 mL irrigation treatment having the highest leachate EC for all fertilizer treatments. Cumulative leachate volumes for the 66 and 100 mL irrigation treatments were unaffected by fertilizer rate, whereas the 132 and 165 mL had greater leaching at the 25% fertilizer rate. Lower irrigation volumes resulted in reduced water and nutrient leaching and higher leachate EC. The higher leachate EC was the result of higher concentration of nutrients in less volume of leachate. The results of this study suggest that a combination of reduced fertilizer rates (up to 50%) and more efficient irrigation can be used to produce salable plants with reduced leaching and thus less environmental impact. [ABSTRACT FROM AUTHOR]

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

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

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

Environmental (i.e., meteorological and landscape) factors and management practices can affect the prevalence of foodborne pathogens in produce production environments. This study was conducted to determine the prevalence of Listeria monocytogenes, Listeria species (including L. monocytogenes), Salmonella, and Shiga toxin-producing Escherichia coli (STEC) in produce production environments and to identify environmental factors and management practices associated with their isolation. Ten produce farms in New York State were sampled during a 6-week period in 2010, and 124 georeferenced samples (80 terrestrial, 33 water, and 11 fecal) were collected. L. monocytogenes, Listeria spp., Salmonella, and STEC were detected in 16, 44, 4, and 5% of terrestrial samples, 30, 58, 12, and 3% of water samples, and 45, 45, 27, and 9% of fecal samples, respectively. Environmental factors and management practices were evaluated for their association with terrestrial samples positive for L. monocytogenes or other Listeria species by univariate logistic regression; analysis was not conducted for Salmonella or STEC because the number of samples positive for these pathogens was low. Although univariate analysis identified associations between isolation of L. monocytogenes or Listeria spp. from terrestrial samples and various water-related factors (e.g., proximity to wetlands and precipitation), multivariate analysis revealed that only irrigation within 3 days of sample collection was significantly associated with isolation of L. monocytogenes (odds ratio = 39) and Listeria spp. (odds ratio = 5) from terrestrial samples. These findings suggest that intervention at the irrigation level may reduce the risk of produce contamination. [ABSTRACT FROM AUTHOR]

The present trial was performed during the two successive growing seasons 2013 and 2014 at a private farm located at sidi salem District, Kafr EL-Sheikh Govemorate to study the impact of irrigation water regime on yield, fruit quality and some water relations of peach trees under heavy clay soils condition. The investigation was carried out on "Early Grand" Peach tress eight years old budded on Nemaguard rootstock and spaced at 5x5 metre apart. The studied soil is heavy clay in texture. The used experimental design in this present is randomized completely block with four replicates. Twenty trees were selected in this study and divided randomly into four groups; each group was subjected to one of the following irrigation treatments: I 1 (standard irrigation practice by local farmers as the control), I2 (giving 12 irrigations through the vegetative growth period), l3 (giving 9 irrigations through the vegetative growth period) and l4 (giving 6 irrigations through the vegetative growth period, which represents water stress conditions on peach plants trees). The data revealed that the highest overall mean values for water applied (Wa) consumptive use (Cu) and consumptive use efficiency (Ecu) were recorded under irrigation treatment 11 and the values are 101.82 cm (4276.52) m 3 /fed.), 66.99 cm. (2813.44m 31 fed.) and 65.79% for Wa, Cu and Ecu, respectively. Meanwhile, the lowest values were recorded under irrigation treatment I 4 and the values are 76.25 cm. (3202.55 m 3 /fed.) 47.61 cm. (1999.66 m 3 /fed.). And 62.47% for Wa, Cu and Ecu, respectively. Concerning, water productivity (WP) and productivity of irrigation water (PIW{, the highest overall mean values were recorded under irrigation treatment I2 and the values are 2.70'kg/m 3 and 1.73 kg/m for WP and PIW, respectively. On the other hand, the lowes_t values were recorded under irrigation treatment I1 (standard) and the values are 2. 16 kg/m 3 and t .43 kg/m 3 for WP and PIW, respectively. Regarding, yield and fruit quality of peach" Early Grand" were significantly affected by irrigation treatments, where, water stress conditions significantly decreased yield and fruit quality except pre-harvest fruit drop(%), V.C Juice, fruit firmness, fruit acidity and TSS /acid ratio which increased under stressful conditions (I4 ), in comparison with other yield and fruit quality parameters were significantly increased under non-stressful treatments, where the highest mean values were recorded under the conditions of irrigation treatment I2 [ABSTRACT FROM AUTHOR]

Quantification of various water use efficiency (crop water productivity) indices for different irrigation regimes can aid in making effective in-season water management decisions and developing crop water productivity models. However, these critical variables can be affected by interannual variation in climatic conditions, and long-term research that provides such data and information is extremely rare. Maize (Zea mays L.) irrigation water use efficiency (IWUE), crop water use efficiency (CWUE), evapotranspiration water use efficiency (ETWUE), annual precipitation use efficiency (ANNPUE), growing season precipitation use efficiency (GRSPUE), and the newly developed growing season precipitation use efficiency with respect to rainfed yield (GRSPUErainfed) were measured under full and limited irrigation and rainfed conditions from 2005 to 2010 in south-central Nebraska. An additional new irrigation efficiency term [irrigation-evapotranspiration use efficiency (IRRETUE)] was developed and tested to evaluate the efficiency of irrigation management with respect to actual crop evapotranspiration (ETa). Four irrigation treatments were imposed [fully irrigated treatment (FIT), 75% FIT, 60% FIT, and 50% FIT] and a control rainfed treatment. CWUE varied from 1.21 kg/m³ for rainfed treatment in the dry year of 2005 to 2.51 kg/m³ for 60% FIT in the below average year of 2009. CWUE exhibited substantial interannual variation. The lowest CWUE was always obtained under rainfed production, whereas the highest value was usually observed under FIT, except in 2009. The FIT and 75% FIT CWUE values were very similar. Six-year average CWUE values were 2.34, 2.32, 2.29, 2.24, and 1.73 kg/m³ for FIT, 75% FIT, 60% FIT, 50% FIT, and rainfed, respectively, with SDs of 0.06, 0.09, 0.14, 0.12, and 0.38 kg/m³, respectively. IWUE varied from 1.75 kg/m³ for 50% FIT in the wettest year (2008) to 5.9 kg/m³ for the same treatment in 2009. The six-year average IWUE values were 4.01, 4.45, 4.48, and 4.13 kg/m³ for FIT, 75%FIT, 60%FIT, and 50% FIT, respectively, with SD values of 0.82, 0.84, 0.83, and 1.88 kg/m³ for the same treatments. There was considerable interannual variation in IWUE for the same treatment; this variation between treatments in a given year was greater than the interannual variation for the same treatment. The IWUE was maximized with limited irrigation treatments (mostly 50% FIT, followed by 75% FIT and 60% FIT). ETWUE values varied from 1.18 for 50%FIT in 2008 to 7.16 kg/m³ for 60%FIT in 2010; ETWUE decreased linearly with seasonal ETa (R² > 0.80) in 2006, 2007, and 2009 and decreased with seasonal ETa, displaying a low R² of 0.26 in 2010. In the wettest year (2008), ETWUE increased with ETa (R² = 0.31). The new efficiency index, IRRETUE, ranged from 37.8% (62.2% underirrigation) for 50% FIT in 2010 to as high as 149.6% (49.6% overirrigation) for 50% FIT in 2008. On a long-term average, IRRETUE values were 87, 93.2, 88, and 89.2% for FIT, 75% FIT, 60% FIT, and 50%FIT, respectively. The new IRRETUE can be a very effective tool to evaluate the effectiveness of irrigation management practices with respect to meeting crop ETa for maximum yield. When the annual precipitation is considered, FIT resulted in greater ANNPUE, followed closely by 75% FIT and other limited irrigation treatments. The GRSPUErainfed values on all-treatment average basis were 32, 46, 66, 90, 61, and 82% (for FIT, 75% FIT, 60% FIT, and 50% FIT) lower than the GRSPUE values from 2005 through 2010.May precipitation consistently had the greatest influence on GRSPUE in all years, with high R² of 0.73, 0.72, 0.71, and 0.76 for FIT, 75% FIT, 60% FIT, and 50% FIT, respectively. The rainfed treatment, however, was most influenced by April precipitation (R² = 0.62). May precipitation was also the most influential on the GRSPUErainfed, with high R² values of 0.67, 0.77, 0.87, and 0.82 for FIT, 75% FIT, 60% FIT, and 50% FIT, respectively. These research results are some of the first long-term research results reported in the literature for full and limited irrigated and rainfed maize productivity indices and can provide invaluable data and information for developing effective in-season water management decisions and determining crop productivity responses to different irrigation/water management conditions. [ABSTRACT FROM AUTHOR]

Quantification of crop response to the amount of water applied, available, or used is important for decision making to ensure effective, profitable, conservative agricultural production. However, these variables and responses may have interannual attributes and long-term research has rarely quantified interannual variations of irrigation-yield production functions (IYPF), evapotranspiration-yield production functions (ETYPF), and yield response factors (Ky). This long-term research measured grain yield, actual crop evapotranspiration (ETa), increase in ETa attributable to various irrigation levels, basal evapotranspiration (ETb; ET required to establish grain yield), IYPF, ETYPF, and seasonal Ky for maize (Zea mays L.) from 2005 to 2010 growing seasons. Four full and limited irrigation levels [fully irrigated (FIT), 75% FIT, 60% FIT, and 50% FIT] and rainfed treatment were imposed. Seasonal ETa increased linearly with increasing irrigation and the slopes of the ETa versus seasonal irrigation relationships exhibited substantial interannual variation. All-treatment average ETa values were 561, 583, 592, 660, 591, and 628 mm from 2005 to 2010, respectively. Irrigation amounts significantly impacted grain yield in all years with considerable variation among seasons. All-treatment average yield increases attributable to irrigation were 7.7, 4.6, 1.6, 5.8, and 2.7 ton/ha, relative to rainfed treatment, from 2005 through 2010, respectively; six-year average yield increase was 4.5 t/ha. Grain yield had a curvilinear relationship with seasonal irrigation amounts (R#178; = 0.79) and yield increased with irrigation up to approximately 180 mm of irrigation water (15.5 t/ha grain yield); thereafter, irrigation became excessive and diminishing returns occurred. Interannual variation of grain yield produced per unit of irrigation was observed owing to differences in rainfed yield response to precipitation. Totals of 0.92, 1.72, 0.09, 1.06, 1.90, and 0.08 t/ha grain yield were produced per 25.4 mm of irrigation applied (beyond the intercept) from 2005 through 2010, respectively. Based on the pooled (average of all years) curvilinear IYPF equation, 25.4 mm of irrigation produced approximately 1.45 t/ha grain yield [beyond intercept (9.29 t/ha)]. Grain yield had a very strong, linear increase with seasonal ETa (R#178; > 0.92). The ETYPFs exhibited less interannual variation than the IYPFs and the slope of the ETYPFs ranged from 0.0336 in 2008 to 0.0662 in 2010, with the wettest year (2008) having the lowest slope. Six-year average ETYPF had a high R2 (0.93) with an average slope of 0.0409. ETb of individual years also exhibited substantial interannual variation: 263, 319, 314, 209, 319, and 418 mm for the 2005, 2006, 2007, 2008, 2009, and 2010 growing seasons, respectively. Six-year average pooled data indicated that 279 mm of ETb is needed to establish grain yield. Based on the ETYPF data from individual years, 25.4 mm of ETa resulted in 0.96, 1.20, 1.14, 0.85, 1.22, and 1.68 t/ha maize yield (beyond the intercept) from 2005 through 2010. When individual treatments were considered, 25.4 mm of ETa resulted in 0.98, 0.40, 0.62, 1.01, and 0.48 t/ha grain yield (beyond intercept) for rainfed, 50% FIT, 60% FIT, 75% FIT, and FIT, respectively. The climatic conditions in August were the most influential in determining the slope of the ETYPFs. Seasonal average Ky also exhibited interannual variation, which was 1.89, 1.89, 1.39, 1.80, and 2.64 in 2006, 2007, 2008, 2009, and 2010, respectively. This research provides important data, information, and analyses in terms of interannual variation of various parameters on maize response to water. [ABSTRACT FROM AUTHOR]

Pennisetum glaucum L. cv. Babala (pearl millet) established as a summer catch crop followed by Avena sativa L. cv Palinup (oats) established as a winter catch crop were irrigated with winery wastewater diluted to eight chemical oxygen demand (COD) levels ranging between 100 mg/L and 3 000 mg/L. The diluted wastewater treatments were compared to irrigation with river water. The dry matter production (DMP) of oats, if not preceded by pearl millet, tended to improve when irrigated with winery wastewater. Growth of pearl millet peaked during the period when 91% of the diluted winery wastewater was applied. Winery wastewater improved the DMP of pearl millet. No trends were observed in the nutrient levels of the above-ground growth of the two interception crops. However, Na levels increased over time. Using both species, too high levels of macro-nutrients were intercepted, but insignificant amounts of Na were removed. Irrigation with winery wastewater with COD levels between 1 500 mg/L and 2 500 mg/L may be sustainable if only pearl millet is employed as an interception crop. Fertiliser needed to maintain the nutrient balance in the soil resulted in an additional cost of approximately R2 800/ha/yr. However, the fodder may provide an income in excess of R15 000/ha/yr. [ABSTRACT FROM AUTHOR]

Two field experiments were conducted to study the response of maize (Zea mays L., cv. Azam) to potassium (K) levels (30, 60, 90 kg ha-1) and K application time (T1 = full at sowing, T2 = full at V9 stage (many ear shoots were easily visible upon dissection), and T3 = 50% each at sowing and V9 stage with and without cattle dung. One experiment was carried out in the field where 5 t ha-1 cattle dung was applied (15 days before sowing), while the field under second experiment received no cattle dung (0 t ha-1). The research was carried out at the Agronomy Research Farm of The University of Agriculture Peshawar during summer 2014. The experiments under both treatments were laid out in randomized complete block design using three replications. The results revealed that the K treated plots (rest) under both treatments had produced more number of leaves plant-1 and mean leaf area, partitioned more dry matter into various plant parts (leaf, stem and ear), and produced more biomass yield and harvest index than control (K not applied). Cattle dung was found more beneficial in terms of more number of leaves plant-1, higher mean leaf area, partitioning of more dry matter into leaf, stem and ear, and producing higher biomass yield and harvest index as compared to the treatment that received no cattle dung. Increasing the rate of K increased number of leaves plant-1 and mean leaf area, partitioned more dry matter into various plant parts (leaf, stem and ear), produced more biomass yield and harvest index and vice versa (90 kg K ha-1 > 60 kg K ha-1 > 30 kg K ha-1). Increase in number of leaves plant-1 mean leaf area, dry matter partitioning into various plant parts (leaf, stem and ear), biomass yield and harvest index was observed when K was applied in two equal splits (50% each at sowing and V9 stage > 100% at sowing > 100% at V9 stage). It was concluded from this study that application of K at the highest rate of 90 kg ha-1 in two equal splits (50% at sowing + 50% at V9 stage) along with cattle dung (5 t ha-1) could improve number and area of leaves, dry matter partitioning, biomass yield and harvest index under limited irrigation condition. [ABSTRACT FROM AUTHOR]

This study was designed to determine the qualitative and microbiological impact of two different sources of irrigation water on tomato fruit: groundwater (GW), as the control, and treated agro-industrial wastewater (SW). The mean tomato fruit quality parameters of dry matter, weight, diameter, colour index, pH, soluble solids content, titratable acidity, Ca2+ and Na+ content were not significantly affected by the different water treatments. Conversely, NO3- contents was significantly higher with GW use, than with SW (2.21 vs 1.62 mg 100 g-1, respectively; P≤0.05). The microbial quality of the tomato fruit was not significantly different across the GW and SW treatments, with no Salmonella spp. isolated from any of the fruit, and the faecal indicators always below 10 CFU g-1. These data show that agro-industrial treated wastewater can be used for irrigation for industrial tomato production once the long-term effects on the agroecosystem have been defined. [ABSTRACT FROM AUTHOR]

The Indus Basin Irrigation System suffers significant inequity in access to surface water across its millions of users. Information, i.e., monitoring and reporting of water availability, may be of value in improving conditions across the basin, and we investigated this via an experimental game of water distribution in Punjab, Pakistan. We found evidence that flow information allowed players to take more effective action to target overuse, and that overall activities that might bring social disapproval were reduced with information. However, we did not find any overall improvement in equity across the system, suggesting that information on its own might not be sufficient to lead to better water distribution among irrigators. [ABSTRACT FROM AUTHOR]