Assess Water Use Research Articles

Applying plant-based irrigation scheduling to assess water use efficiency of cotton following a high-biomass rye cover crop

BackgroundThis study addressed the potential of combining a high biomass rye winter cover crop with predawn leaf water potential (ΨPD) irrigation thresholds to increase agricultural water use efficiency (WUE) in cotton. To this end, a study was conducted near Tifton, Georgia under a manually-controlled, variable-rate lateral irrigation system using a Scholander pressure chamber approach to measure leaf water potential and impose varying irrigation scheduling treatments during the growing season. ΨPD thresholds were − 0.4 MPa (T1), − 0.5 MPa (T2), and − 0.7 MPa (T3). A winter rye cover crop or conventional tillage were utilized for T1-T3 as well.ResultsReductions in irrigation of up to 10% were noted in this study for the driest threshold (− 0.7 MPa) with no reduction in lint yield relative to the − 0.4 MPa and − 0.5 MPa thresholds. Drier conditions during flowering (2014) limited plant growth and node production, hastened cutout, and decreased yield and WUE relative to 2015.ConclusionsWe conclude that ΨPD irrigation thresholds between − 0.5 MPa and − 0.7 MPa appear to be viable for use in a ΨPD scheduling system with adequate yield and WUE for cotton production in the southeastern U.S. Rye cover positively impacted water potential at certain points throughout the growing season but not yield or WUE indicating the potential for rye cover crops to improve water use efficiency should be tested under longer-term production scenarios.

Correction: Mayer, A., et al. A Comprehensive Modelling Approach to Assess Water Use Efficiencies of Different Irrigation Management Options in Rice Irrigation Districts of Northern Italy. Water 2019, 11, 1833

In the published article [1] the authors noticed an error in the ‘Percolation or Capillary Rise’ values reported in Table 4, column 4, and wish to make the following correction to their paper [1]: Table 4 should be replaced with the following: Actual Evapotranspiration (mm) Irrigation (mm) Percolation (−) or Capillary Rise (+) (mm) WUE (%) Maize 449 620 (438, 705) −589 (−243, −732) 50 (61, 44) Irrigated poplar 348 300 (300, 300) −247 (−215, −252) 57 (50, 58) Rainfed poplar 487 0 −18 (+232, −57) 159 (149, 159) WDA rice 537 1394 (964, 1620) −1002 (−491, −1206) 34 (43, 29) WFL rice 592 1852 (1508, 2210) −1266 (−860, −1693) 28 (32, 23) [...]

Water productivity and footprint of major Brazilian rainfed crops – A spatially explicit analysis of crop management scenarios

Green water is a central resource for global agricultural production. Understanding its role is fundamental to design strategies to increase global food and feed production while avoiding further land conversion, and obtaining more crop per drop. Brazil is a country with high water availability, and a major exporter of agricultural goods and virtual water. We assess here water use and water productivity in Brazil for four major rainfed crops: cotton, maize, soybeans, and wheat. For this, we use the EPIC crop model to perform a spatially explicit assessment of consumptive water use and water productivity under crop management scenarios in Brazil between 1990 and 2013. We investigate four different land-water interactions: (i) water use and productivity for different management scenarios, (ii) the potential of supplemental irrigation for productivity improvement, (iii) changes in green water use throughout the study period, and finally (iv) potential reduction of land and water demand related to agricultural intensification. The results show that, for the studied crops, green water is the main resource for biomass production, and intensification can lead to great improvements in green water productivity. The results also suggest that, despite achieving higher yields, irrigation-based intensification tends to lower overall water productivity, compared to fertilizer-based intensification strategies. This is, however, regionally and crop-specific. Furthermore, due to higher yields and water productivity, producing the same amount of crop output in irrigated or rainfed intensification scenarios would result in the reduction of resource demand, in the order of 34–58 % for cropland, and 29–52 % for water.

A review of the assessment of sustainable water use at continental-to-global scale

Freshwater scarcity and unsustainable water use are just some of the growing concerns in many parts of the world. Increasing water demand accompanied by a changing climate can lead to unsustainable use of freshwater resulting in water scarcity. Several studies have quantified sustainable water use and water scarcity at a continental-to-global scale in the past. This review focuses on the large-scale water resources assessments and the methods by which sustainable water use and water scarcity are quantified. The review is structured based on a framework that comprises the main components of water demand and supply and other aspects of sustainable water use including virtual water trade and future projections of sustainable water use. The major components of water demand and supply in such assessments are increasingly derived from global earth system models and national-level census datasets. These assessments conclude that the selection of appropriate spatial and temporal scales is critical. The grid-based global earth system models enable better spatial resampling of water information across country/political boundaries. Similarly, by refining the temporal scale from annual (the most commonly used temporal scale of assessment) to monthly time steps, water scarcity is better captured due to the distinctive seasonality of water availability and demand. This paper also discusses the role of major drivers of water scarcity. Although both changing climate and increasing water demand contribute to water scarcity, the majority of the literature concludes that the demand-driven freshwater scarcity has a much greater impact than that induced by climate change.

Valoración del uso del agua en la isla de San Andrés: turistas, hoteles y viviendas turísticas

In 2016, the island of San Andres in the Colombian Caribbean was declared a public calamity because it did not have enough water resources to meet the water demand of a growing resident and floating population. At the same time, there is a model of mass tourism that is rooted in relative scarcity and to understand its impact, this paper makes an analytical assessment of water use in the accommodation service: it documents the perception, patterns of use and saving strategies that tourists, hoteliers, tourist homes and government entities have about water and finally the signs of conflict between the tourism sector and residents over the resource.

The Arkansas “Most Crop per Drop” Contest: An Innovative Extension Method to Improve Irrigation Water Management Adoption

HighlightsAn integrated research and Extension program promoted adoption of computerized hole selection (CHS), surge irrigation, soil moisture monitoring, and multiple inlet rice irrigation (MIRI) for surface irrigators in Arkansas.Using a contest design, water use efficiency (WUE) was determined for maize, soybean, and rice fields, and report cards were provided to contest participants to provide feedback on their irrigation acumen.The highest yielding fields did not always result in the highest WUE.The contest was implemented on working commercial farms in the Arkansas Delta using flowmeters and in-field crop yield checks for the purpose of promoting adoption of irrigation water management (IWM).Abstract. The Arkansas “most crop per drop” irrigation contest is an integrated research and Extension program developed to assess water use, rainfall, and yield for the purpose of estimating water use efficiency (WUE). The irrigation contest resembles traditional yield contests, with the goal of documenting WUE and increasing adoption and awareness of irrigation water management (IWM) practices in the region. Adoption of IWM practices was greater for those who participated in the contest than their Arkansas peer average, with documented adoption increases of 33% for computerized hole selection, 28% for surge irrigation, and 51% for soil moisture monitoring. Keywords: Computerized hole selection, Soil moisture monitoring, Surge irrigation.

Carbon isotope discrimination association with yield and test weight in Pacific Northwest–adapted spring and winter wheat

AbstractDue to considerable influence of environment on yield, breeding for drought tolerance could benefit from focusing on selection of more heritable physiological traits, such as carbon isotope discrimination (as measured by delta, ∆) for indirectly assessing water use efficiency (WUE) of wheat (Triticum aestivum L.). Spring and winter wheat cultivars were assayed for ∆, and these values were used to determine the relationships with performance in over 13 environments in the U.S. Pacific Northwest. The correlation coefficients of ∆ values between the wheat cultivars grown in different environments ranged from 0.11 to 0.73 for both spring and winter wheat. There was significant genotypic variation for ∆ in soft spring and hard winter wheat but not in hard spring and soft winter wheat. The ∆ values were poor indicators of yield for this set of wheat cultivars in most environments, although low values (better WUE) were sometimes correlated with yield. A population of 165 hard spring wheat recombinant inbred lines derived from a cross between two hard spring wheat varieties that differed in ∆ was also screened in low‐rainfall dryland and irrigated environments. High yields in this recombinant inbred population were weakly correlated with high ∆ values or low WUE in most environments.

Application of CROPWAT program for assessment of sweet corn water use

Application of CROPWAT program for assessment of sweet corn water use

Optimising water requirement for nursery rearing of rohu Labeo rohita (Hamilton, 1822) in large outdoor concrete tanks: influence of water depth on seed performance

A study was conducted to find the optimum water depth requirement for nursery rearing of rohu Labeo rohita (Hamilton, 1822). Nine concrete tanks of 50 m2 each (10 x 5 x 1.2 m) were grouped into three treatments T1, T2 and T3 and were filled upto 1.0, 0.75 and 0.5 m water depths, respectively. Each tank was stocked with 0.5 lakh hatchery produced spawn and reared for 20 days. The study revealed significant influence of water depth on growth and survival of fry (p<0.05). Though the final length of fry did not differ among the treatments (p>0.05), T3 with 0.5 m water depth showed significantly lower survival, final body weight and specific growth rate than the other two treatments (p<0.05), whereas tanks with 1.0 and 0.75 m water depths showed almost similar survival, final weight and SGR (p>0.05). Assessment of water use for production of every 1000 fry revealed significant reduction in total water use (TWU) with decreased water depth (p<0.05), while the consumptive water use (CWU) in terms of water exchange and replenishment did not differ between water depth treatments of 1.0 and 0.75 m. The results of the study indicate 0.75 m to be the ideal water depth with better water use efficiency for fry production of the species.

"Теоретико-методологічні основи кількісної оцінки екологічної оптимізації водокористування міст"

"Теоретико-методологічні основи кількісної оцінки екологічної оптимізації водокористування міст"

Assessment of Agricultural Water Use in Uzbekistan using Radiation Balance Method with Radiometric Data MODIS

The spatial images of agricultural water use in the irrigated lands of Khorezm region, located in the lower reaches of the Amudarya River, were mapped and monitored using the data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS). Land use categories at the case study areas were classified using a recursive partitioning and regression tree with 250 m MODIS NDVI time series. A seasonal existing evapotranspiration (ET) rate was obtained through application of the Surface Energy Balance Algorithm for Land to 1 km daily in MODIS data. In the Khorezm region, a seasonal maximum values for ET was estimated at 1,000 and 1,200 mm for cotton and rice fields, respectively.

Irrigation Requirement for Eucalyptus pellita during Initial Growth

The growth of Eucalyptus pellita in forestry plantations requires attention to water requirements, especially in the initial growth phase from seedling to field-ready plant. In this study, actual evapotranspiration (ETa), crop coefficient (Kc), and the irrigation requirement of E. pellita were assessed during the nursery growth phase (day 40–142). The experimental set-up included lysimeters with different treatments in terms of plants, drainage, and soil conditions. Plant growth and water balance were monitored during June September 2018 in an open nursery area in Riau, Indonesia. ETa was determined by the water balance lysimeter method and potential (reference) evapotranspiration (ETo) was extracted based on the Penman-Monteith method (FAO/56). The results showed that the average Kc value for E. pellita at age 40–142 days is 0.79, which exceeds that reported for E. grandis. The recommended irrigation requirement varies depending on precipitation, from 70 mL/plant/day with no rainfall to zero at precipitation of >30 mm/day. This is the first study to assess water use in E. pellita growing in pots during the nursery phase, which provides guidance on irrigation requirements during their initial growth phase.

A Comprehensive Modelling Approach to Assess Water Use Efficiencies of Different Irrigation Management Options in Rice Irrigation Districts of Northern Italy

European rice production is concentrated in limited areas of a small number of countries. Italy is the largest European producer with over half of the total production grown on an area of 220,000 hectares, predominantly located in northern Italy. The traditional irrigation management (wet seeding and continuous flooding until few weeks before harvest—WFL) requires copious volumes of water. In order to propose effective ‘water-saving’ irrigation alternatives, there is the need to collect site-specific observational data and, at the same time, to develop agro-hydrological models to upscale field/farm experimental data to a spatial scale of interest to support water management decisions and policies. The semi-distributed modelling system developed in this work, composed of three sub-models (agricultural area, groundwater zone, and channel network), allows us to describe water fluxes dynamics in rice areas at the irrigation district scale. Once calibrated for a 1000 ha district located in northern Italy using meteorological, hydrological and land-use data of a recent four-year period (2013–2016), the model was used to provide indications on the effects of different irrigation management options on district irrigation requirements, groundwater levels and irrigation/drainage network efficiency. Four scenarios considering a complete conversion of rice irrigation management over the district were implemented: WFL; DFL—dry seeding and delayed flooding; WDA—alternate wetting and drying; WFL-W—WFL followed by post-harvest winter flooding from 15 November to 15 January. Average results for the period 2013–2016 showed that DFL and WDA would lead to a reduction in summer irrigation needs compared to WFL, but also to a postponement of the peak irrigation month to June, already characterized by a strong water demand from other crops. Finally, summer irrigation consumption for WFL-W would correspond to WFL, suggesting that the considered winter flooding period ended too early to influence summer crop water needs.

“Quantifying spatiotemporal impacts of the interaction of water scarcity and water use by the global semiconductor manufacturing industry”

The high-tech semiconductor manufacturing sector is integral to the international electronics industry and was valued at over $400 billion USD in 2017. Intensive water use by this industry is well-documented and this work provides a spatially explicitly assessment of water use impacts by nearly 100% of global semiconductor manufacturing capacity. Both direct manufacturing water use and water use from electricity were considered as part of a facility’s total withdrawal. Manufacturing water withdrawals were estimated by using technology-specific water and electricity use data, reported at the semiconductor chip or wafer level from the life cycle literature and industry estimates. Electricity water use intensity (WUI) factors were gleaned from the literature and regional electricity WUI factors were derived for China and the U.S. Geolocation of semiconductor manufacturing facilities allowed for summation of water withdrawals at various spatial extents (i.e. watershed, country, and globally). This data was combined with calculated regional or country-level electricity water use factors to estimate total water withdrawals by a facility. Geolocation of data also allowed for calculation of watershed specific scarcity-weighted withdrawals. Scarcity-weighted withdrawals were ascertained by multiplying facility water withdrawal data by the AWaRE water scarcity characterization factor available for each of 202 watersheds associated with semiconductor manufacturing facilities. These data were used to identify and map hotspots of industry water use, which is especially important for areas of industry growth such as China. This analysis is useful as a benchmark for global semiconductor industry water withdrawals and may assist OEMs in decisions about supply chain sourcing. This could also guide semiconductor manufacturers in prioritizing locations and time periods to implement water-saving technologies or employ less water intensive electricity sources. Additionally, the spatially explicit water use data for the semiconductor sector can be used to improve existing databases of national and regional sector-specific water use coefficients that are often applied in LCA input-output studies.

Irrigation efficiency and water-saving potential considering reuse of return flow

Irrigation efficiency (IE) and water-saving potential (WSP) are two fundamental parameters for assessing water use and management in irrigation systems. A new calculation method was proposed herein to accurately estimate the IE and WSP in irrigation systems. The proposed method considers the reuse of return flow. A modified Soil and Water Assessment Tool (SWAT) was used to simulate hydrological processes under various water-saving scenarios for the Yangshudang (YSD) watershed within the Zhanghe Irrigation System (ZIS) in Hubei Province, China. The dry year of 2010 was chosen as a study case. Based on simulation results, the traditional irrigation efficiency (IE0) and water-saving potential (WSP0) as well as the irrigation efficiency taking into account the reuse of return flow (IEr) and water-saving potential considering the reuse of return flow (WSPr) were calculated for various scenarios. The relationships between the two IE indicators and the cause thereof, as well as the two WSP values, were analyzed and explored. The results showed that both IE and WSP were improved with the enhancement of water saving. As long as there was the reuse of return flow, IEr must be greater than IE0. Moreover, in terms of water-saving approaches that improved the reuse rate of return flow, WSPr was determined to be greater than WSP0, thereby suggesting that the traditional method underestimated the WSP. However, for water-saving approaches that reduced the reuse rate of return flow, WSPr was determined to be less than WSP0, which suggested that the traditional method overestimated the WSP. The relationship between WSP0 and WSPr was attributed to the fact that WSPr was calculated by subtracting the amount of the water saved by the reuse of return flow on the basis of WSP0, and this difference can be either positive or negative. Therefore, the managers of irrigation systems should use IEr as the actual IE but not IE0, and use WSPr instead of WSP0 to evaluate the actual WSP.

Effect of Drought and Topographic Position on Depth of Soil Water Extraction of Pinus sylvestris L. var. mongolica Litv. Trees in a Semiarid Sandy Region, Northeast China

Drought and topographic position are the most important factors influencing tree growth and survival in semiarid sandy regions of Northeast China. However, little is known about how trees respond to drought in combination with topographic position by modifying the depth of soil water extraction. Therefore, we identified water sources for 33-year-old Mongolian pine (Pinus sylvestris L. var. mongolica Litv.) trees growing at the top and bottom of sand dunes by comparing stable isotopes δ2H and δ18O in twig xylem water, soil water at various depths and groundwater during dry and wet periods. Needle carbon isotope composition (δ13C) was simultaneously measured to assess water use efficiency. Results showed that when soil moisture was low during the dry period, trees at the top used 40–300 cm soil water while trees at the bottom utilized both 40–300 cm soil water and possibly groundwater. Nevertheless, when soil moisture at 0–100 cm depth was higher during the wet period, it was the dominant water sources for trees at both the top and bottom. Moreover, needle δ13C in the dry period were significantly higher than those in the wet period. These findings suggested that trees at both the top and bottom adjust water uptake towards deeper water sources and improve their water use efficiency under drought condition. Additionally, during the dry period, trees at the top used shallower water sources compared with trees at the bottom, in combination with significantly higher needle δ13C, indicating that trees at the bottom applied a relatively more prodigal use of water by taking up deeper water (possibly groundwater) during drought conditions. Therefore, Mongolian pine trees at the top were more susceptible to suffer dieback under extreme dry years because of shallower soil water uptake and increased water restrictions. Nevertheless, a sharp decline in the groundwater level under extreme dry years had a strong negative impact on the growth and survival of Mongolian pine trees at the bottom due to their utilization of deeper water sources (possibly groundwater).

A screening approach to improve water management practices in undeveloped shale plays, with application to the transboundary Eagle Ford Formation in northeast Mexico

Hydraulic fracturing (HF) operations have transformed the unconventional energy industry, leading to a global increase in hydrocarbon production. Despite this, only the US, China, Canada and Argentina currently dominate production of unconventional resources, with the majority of shale basins globally remaining unprofitable to develop. An important gap in current water-energy nexus research, which this study addresses, is the assessment of potential water use to satisfy HF procedures in emergent plays. This work presents a screening tool for assessing first-order estimates of water impacts in undeveloped shale plays, testing the approach in the transboundary Eagle Ford (EF) play in northeast Mexico. We couple surface water and groundwater stress indicators derived from global hydrological variables to depict a baseline water stress index. Relative water stress is mapped for proposed blocks to be leased by the Mexican government in the future. We simulate four HF scenarios to assess new total water stress indicators for each block, considering shale production schemes using representative well drilling density (well lateral length(s) per unit area) and HF water intensity (HF water volume per unit lateral length) from existing EF development in Texas. Results suggest that the most feasible management scenario would consider the drilling of ∼1360 new unconventional wells/yr with projected HF water use of ∼57 Mm3/yr (0.7% of the total water withdrawals). The remaining scenarios will largely affect groundwater resources. Though applied to the EF in Mexico, this screening tool can assess water use constraints in emerging unconventional plays globally.

Assessing Water Use, Energy Use And Carbon Emissions In Lift‐ Irrigated Areas: A Case Study From Karshi Steppe In Uzbekistan

AbstractThe advantages of a nexus approach in addressing complex environmental challenges are becoming increasingly clear. In Central Asia, however, the nexus between water–food–energy has not received adequate attention, as the very few studies that have been conducted fell short of quantifying nexus trade‐offs and benefits at a practical, small scale. This paper applies a quantitative accounting method to assess water and energy use intensity in irrigated areas of the Karshi Steppe of Central Asia that are supplied by pumping water uphill (lift‐irrigated) from the underlying river. The results indicated that the potential water and energy savings as well as the greenhouse gas (GHG) emission reductions could be achieved by applying an optimal planning deficit irrigation schedule simulated using CROPWAT 8. Some 575 MCM (million cubic metres) of water and 259 GWh of electricity can be saved, while the CO2 equivalent emissions can be reduced by almost 122 000 t. Achieving these savings requires a mix of technical and policy components. This paper describes an example of proper irrigation planning as a tool for water/energy savings and consequent reduction of CO2 emissions. © 2019 John Wiley & Sons, Ltd.

Water use of selected grain legumes in response to varying irrigation regimes

Grain legumes have potential to contribute to food and nutritional security in water-scarce areas. Information on their yield, water use and water productivity (WP) would be useful for their promotion. The aim of the study was to make a comparative assessment of adaptation, yield, water use and WP of an African indigenous grain legume (bambara groundnut) and two major grain legumes (dry bean and groundnut) under rainfed, deficit and optimum irrigation conditions. Field trials were conducted during the 2015/16 and 2016/17 summer seasons in KwaZulu-Natal, South Africa, using a split-plot design arranged in completely randomised blocks with three replications. Data collected included stomatal conductance, leaf area index, timing of key phenological stages and yield. Water use was calculated as a residual of the soil water balance. Water productivity was obtained as the quotient of grain yield and water use. Crops adapted to limited soil water availability through stomatal regulation and reduction in canopy size and duration. Yield, yield components and WP varied significantly (P < 0.05) among crop species. During 2015/16, groundnut had the highest yield and WP (10 540 kg·ha−1 and 0.99 kg·m−3, respectively). During 2016/17, the highest yield and WP were observed in dry bean, 2 911 kg·ha−1 and 0.75 kg·m−3, respectively. For both seasons, dry bean had the lowest water use (143–268 mm) across all water treatments. Dry bean and groundnut out–performed bambara groundnut with respect to yield, harvest index and WP. For any promotion of bambara groundnut as an alternative crop, there is need for crop improvement to improve yield and WP.

Anthropic impacts on Sub-Saharan urban water resources through their pharmaceutical contamination (Yaoundé, Center Region, Cameroon)

Sub-Saharan urban centers have to tackle high population growth, lack of sanitation infrastructures and the need for good quality water resources. To characterize the impacts of anthropization on the water resources of the capital of Cameroon (Yaoundé), a multi-disciplinary approach was used in ten sub-watersheds (peri-urban and urban) of the Méfou watershed. Pharmaceutical residues were used as tracers of surface and groundwater contamination caused by the release of domestic wastewater from pit latrines and landfills. A water use survey was conducted in the vicinity of the sampling sites to better assess water use, treatment and management. Available land use and hydro-geomorphological data completed characterization of the sub-watersheds. The combined data showed that natural features (elevation, slope, and hydrography) and human activities (land use) favor rainfall-runoff events and hence surface water contamination. Pharmaceutical monitoring revealed contamination of both surface and groundwater especially in the urban sub-watersheds. Analgesics/anti-inflammatory drugs and anti-epileptic carbamazepine were the most frequently found compounds (in up to 91% of water samples) with concentrations of acetaminophen reaching 5660 ng/L. In urban sub-watersheds, 50% of the groundwater sites used for drinking water were contaminated by diclofenac (476–518 ng/L), carbamazepine (263–335 ng/L), ibuprofen (141–276 ng/L), sulfamethoxazole (<2–1285 ng/L) and acetaminophen (110–111 ng/L), emphasizing the need for a deeper understanding of the interactions between surface and groundwater. The use of groundwater as drinking water by 68% of the total population surveyed raises concerns about population exposure and potential health risks. This case study highlights the need for strategies to limit contamination of the water resource given the predicted future expansion of Sub-Saharan urban centers.