Agricultural Water Reservoirs Research Articles

A Strategy to Quantify Water Supply of an Agricultural Reservoir for Integrated Water Management Policy

A data-driven approach is required to scientifically manage agricultural water resources in accordance with the integrated water management policy of South Korea. In this study, a quantification strategy is presented to calculate reservoir supply by comparing the results with the actual reservoir water storage. Strategies considering current calculation methods were divided into canal flow measurement (S1), theoretical flow rate (S2), water storage decrease in field practice (S3), and water demand in design practice (S4), utilizing water levels of the reservoir and its canal and the level–flow rate curve obtained from surveying the canal flow. Each strategy was assessed through hydrological verification of reservoir water balance modeling. Based on the determination coefficient (R2), Nash–Sutcliffe efficiency (NSE), and relative error (RE) values, the S1 method was found to be the most suitable. S2 had lower reliability than S1, while S3 and S4 satisfied neither R2 nor NSE and had a larger RE than S1 and S2. To accurately quantify agricultural water supplies, the importance of directly measuring reservoir canal flows must be emphasized using automatic water level and flow gauges in canals. This study provides insights into more scientific management of agricultural reservoir water supplies and more effective monitoring of agricultural water usage.

Two multistate outbreaks of a reoccurring Shiga toxin-producing Escherichia coli strain associated with romaine lettuce: USA, 2018-2019.

Leafy green vegetables are a common source of Shiga toxin-producing Escherichia coli O157:H7 (STEC O157) foodborne illness outbreaks. Ruminant animals, primarily cattle, are the major reservoir of STEC O157. Epidemiological, traceback and field investigations were conducted to identify potential outbreak sources. Product and environmental samples were tested for STEC. A reoccurring strain of STEC O157 caused two multistate outbreaks linked to romaine lettuce in 2018 and 2019, resulting in 234 illnesses in 33 states. Over 80% of patients interviewed consumed romaine lettuce before illness. The romaine lettuce was sourced from two California growing regions: Santa Maria and Salinas Valley in 2018 and Salinas Valley in 2019. The outbreak strain was isolated from environmental samples collected at sites >90 miles apart across growing regions, as well as from romaine-containing products in 2019. Although the definitive route of romaine contamination was undetermined, use of a contaminated agricultural water reservoir in 2018 and contamination from cattle grazing on adjacent land in 2019 were suspected as possible factors. Preventing lettuce contamination from growth to consumption is imperative to preventing illness. These outbreaks highlight the need to further understand mechanisms of romaine contamination, including the role of environmental or animal reservoirs for STEC O157.

Introducing affordable and accessible physical covers to reduce evaporation from agricultural water reservoirs and pools (field study, statistics, and intelligent methods)

Introducing affordable and accessible physical covers to reduce evaporation from agricultural water reservoirs and pools (field study, statistics, and intelligent methods)

Controversy over the Use of “Shade Covers” to Avoid Water Evaporation in Water Reservoirs

Water scarcity and sustainability are main current concerns affecting billions of people worldwide. Apart from policies designed to guarantee water supply, technologies and procedures have been developed to optimize the uses of water and water recycling as well as to minimize water scarcity. Among these technologies, those based on the use of bioinspired fibres, membranes, nanomaterials, liquid-liquid extraction methods using ionic liquids or approaches involving plants or microbes have been successfully carried out. One of the main problems associated with most of these technologies is the high cost of their implementation and maintenance. Consequently, other cheaper strategies have been explored, such as the use of shade covers. The objective of this work is to summarize the most recent findings on the use of shade covers (suspended shade cloth covers and shade objects) on water reservoirs, mainly agricultural water reservoirs (AWRs). Reflections on the investment-benefit relationship of this technological proposal are also herein discussed. Apart from traditional shade cloth clover, more recently, other covers like shade balls/squares/hexagons (shady objects) have also been proposed as promising approaches to save water and keep its quality. However, the manufacturing of shady objects, mainly made of polyethylene plastic, results in: (i) high cost (high energy cost and use of raw materials like crude oil and natural gas); (ii) significant production of residues, and (iii) visual environmental pollution. The main conclusion reached from this review is that the controversy over the use of shade covers continues in the spotlight of scientists, water managers, and related companies; although this approach saves water and prevents water quality deterioration, a large number of recalcitrant residues are produced, not only during their production, but also when they must be replaced due to deterioration.

Estimation of Agricultural Reservoir Water Storage Based on Empirical Method

Estimation of Agricultural Reservoir Water Storage Based on Empirical Method

Source dynamics of radiocesium-contaminated particulate matter deposited in an agricultural water reservoir after the Fukushima nuclear accident

The Fukushima nuclear accident in Japan resulted in the deposition of radiocesium over forested and rural landscapes northwest of the power plant. Although there have been several investigations into the dynamics of contaminated river sediment, less attention has been paid to the sources of deposited particulate matter in dams and reservoirs. In the Fukushima Prefecture, there are 10 significant dams and over a 1000 reservoirs for both agricultural and surface water management. These reservoirs may have trapped a significant volume of radiocesium-contaminated sediment. Therefore, characterizing the sources of contaminated particulate matter is important for the ongoing management of contamination in the region.Accordingly, the composition of particulate matter deposited in the Mano Dam reservoir, approximately 40km northwest of the power plant, was investigated with the analyses and modelling of carbon and nitrogen stable isotope ratios (δ13C and δ15N), total organic carbon (TOC) and total nitrogen (TN) concentrations. Four sediment cores, with lengths ranging 29–41cm, were sampled in the Mano Dam. Source samples from 46 forest soils, 28 cultivated soils and 25 subsoils were used to determine the source contributions of particulate matter. Carbon and nitrogen parameters were analyzed on all samples and a concentration-dependent distribution modelling approach was used to apportion source contributions.Three of the four cores sampled in the Mano Dam reservoir had distinct radiocesium peaks representative of the initial post-accident wash-off phase. Cultivated sources were responsible for 48±7% of the deposited fine particulate matter whereas forests were modelled to contribute 27±6% and subsoil sources 25±4%. Ongoing decontamination of cultivated sources in the Fukushima region should result in a decrease of contaminated matter deposition in reservoirs.

Evaluation of the Relationship between Meteorological, Agricultural and In-situ Big Data Droughts

The purpose of this study is to find the relationship between precipitation deficit, SPI(standardized precipitation index)-12 month, agricultural reservoir water storage deficit and agricultural drought-related big data, and to evaluate the usefulness of agricultural risk management through big data. For the long term drought (from January 2014 to September 2015), each data was collected and analysed with monthly and Provincial base. The minimum SPI-12 and maximum reservoir water storage deficit compared to normal year were occurred at the same time of July 2014, and August and September 2015. The maximum frequency of big data was occurred at June and July of 2014, and March and June to September of 2015. The maximum big data was occurred 1 month advanced in 2014 and 2 months advanced in 2015 than the maximum reservoir water storage deficit. The occurrence of big data was sensitive to spring drought from March, late Jangma of June, dry Jangma of July and the rainfall deficit of September 2015. The big data was closely related with the meteorological drought and agricultural drought. Because the big data is the in situ feeling drought, it is proved as a useful indicator for agricultural risk management.

Comparative Analysis of on-Farm Reservoir Management Techniques and Their Effect on Filtering Requirements for Irrigation

This study identifies and quantifies the operational advantages of covering agricultural water reservoirs (AWRs) for irrigation by means of Suspended Shade Cloth Covers (SSCCs) in comparison with other traditional management practices: Casual Chemical Treatment (CCT) and Systematic Chemical Treatment (SCT). The operational advantages, including the cost-effectiveness, were analysed by carrying out filtering trials at ten sites in south-eastern Spain, where the effect of each technique on algae presence and filtering requirements for microirrigation was evaluated. The results evidenced that AWR management can significantly affect the quality of stored water, with SSCC being the most effective practice in controlling algae presence. Filtering trials corroborated the extraordinary performance of SSCCs since they presented much higher volumes of treated water until filter saturation, two and three orders of magnitude higher than the CCT and SCT management practices, respectively. This result would imply a total annual reduction in operational costs due to the SSCC installation ranging from 359.6 to 598.0 € y−1 when comparing with the CCT, and of 403.2 € y−1 in the case of SCT. Therefore the effect on filtering requirements is an essential consideration in the SSCCs cost-effectiveness assessment.

농업용 저수지 용수공급 모의 시스템의 개발

The objective of this study was to develop agricultural reservoir water supply simulation system to assess water cycle of agricultural water district. Developed system was named as ARWS (Agricultural Reservoir Water supply simulation System). ARWS consists of platform and independent modules. In ARWS, reservoir inflow was calculated using Tank model, and agricultural water supply was calculated considering current farming period and mid-summer drainage. ARWS was applied to simulate water level of Gopung and Tapjung reservoir in 2011 2012. The results were compared to simulation results of HOMWRS and observed data. Average R, EI, RMSE of ARWS were 0.76, 0.46, 1.78 (m), average R, EI, RMSE of HOMRWS were 0.88, -0.14, 2.37 (m) respectively. Considering statistical variances, water level simulation results of ARWS were more similar to observed data than HOMWRS. ARWS can be useful to estimate reservoir water supply and assess hydrological processes of agricultural water district.

Water balance in artificial on-farm agricultural water reservoirs for the irrigation of intensive greenhouse crops

The intensive-cropping system used in southeastern Spain is one of the most productive of the European Union. It is based on the efficient use of irrigation water using localised irrigation systems with water obtained mostly from small artificial on-farm agricultural water reservoirs (AWRs) that meet the evapotranspiration demands of the intensive greenhouse crops.Several public and private initiatives have attempted to optimise the distribution of the water from wells and desalinating plants to avoid losses in the delivery network. However, the AWR water loss to evaporation could be dramatically reduced with the use of plastic shade materials. In addition, simple water-collection devices for capturing rainwater from the greenhouse roofs, which are currently used in more than half of the greenhouses of the study zone, recirculate water to the irrigation AWRs, significantly improving the water balance of the system.The present work provides a monthly balance of the water deficit that could be overcome in an AWR over an irrigation season considering the rainwater directly received by the AWR, the losses due to direct evaporation from the AWR, and the water demand that must be met to provide sufficient irrigation. These water balances were compared with those that would occur if the AWR had been covered with shading material to reduce direct evaporation and if the rainwater from the greenhouse roofs had been collected in the AWR. When applying both of these management approaches, the annual water deficit decreased by 53.02%

FAHP 기법에 의한 농업용저수지의 추가저수량 확보사업 우선순위 결정

본 논문은 퍼지집합이론을 이용한 다기준 의사결정(MCDM) 과정에 관한 연구이며, 농업용 저수지의 수자원계획 평가에 관한 가장 합리적이고 효율적인 방법을 찾기 위해 FAHP를 이용하여 각각의 대안들에 대한 우선순위를 정하였다. 농업용 저수지의 추가저수량 확보를 위해 의사결정자 및 수혜자가 동시에 만족하는 조건을 조사하여 6개의 주 기준을 설정하고 이에 따른 10개의 대안을 설정하여 우선순위를 결정하고자 하였으며, 우선순위를 결정에서의 불확실성과 모호성을 규명하기 위해 퍼지수와 언어변수를 정의하였다. 또한 적절한 의사결정모형의 제시를 위해 의사결정 방법에 따른 분석결과를 비교 검토하였으며 FAHP 기법 적용의 타당성을 논의하였다. This paper presents the application of fuzzy set theory in multi criteria decision making (MCDM). FAHP (Fuzzy Analytic Hierarchy Process) method was used to rank alternatives to find the most reasonable and efficient way of agricultural reservoir water resources assessment. 6 criteria and 10 subcriteria had been identified and compared to secure agricultural water resources. Fuzzy numbers and linguistic variables were presented to address inherently uncertain or imprecise data. Comparison analysis of decision making method was also carried out to find a way of suitable decision making and validity of FAHP was discussed.

Physical, chemical and microbiological effects of suspended shade cloth covers on stored water for irrigation

The present study aims to identify the effect of installing Suspended Shade Cloth Covers (SSCCs) on the water quality of Agricultural Water Reservoirs (AWRs) for irrigation. Four AWRs located in the irrigated coastal plane of the Segura River Basin (south-eastern Spain) were monitored for 1 year. Two of them were covered with a black polyethylene SSCC, whereas the two others remained uncovered during the trial. The main physical, chemical and microbiological water quality parameters were monthly monitored with a multi-parametric instrument OTT-DS5 and water samples analysis. Additionally, a laboratory experiment replicating covered and uncovered AWR conditions was carried out to analyze the influence of water temperature and light intensity on the evolution of bacteria populations.The low transmitted solar radiation of the SSCC dramatically reduced the photosynthesis activity, limiting the algal bloom in covered AWRs. Despite this photosynthesis restriction and the lack of turbulence, the oxygen levels remained close to saturation in the covered AWRs as a result of the frequent water inflows. The installation of the cover also led to a reduction of 82% in Escherichia coli and faecal coliforms, partly due to the reduction of organic matter (mainly algae) and partly because of the lower water temperature. Data from the laboratory experiment confirmed the field results. Overall, the results show the implementation of SSCCs in AWRs produces significant effects in the stored water quality, which are mainly beneficial for irrigation purposes, especially in drip irrigation systems and when reclaimed water is reused.

Effects of a suspended shade cloth cover on water quality of an agricultural reservoir for irrigation

Water availability and quality are two fundamental factors for agriculture in arid and semi-arid regions. This study evaluates the effects of a water-permeable, Suspended Shade Cloth Cover (SSCC), on the quality of water stored in an on-farm Agricultural Water Reservoir (AWR). Water quality (water temperature, electrical conductivity, chlorophyll-a concentration, dissolved oxygen concentration and water turbidity) and environmental (evaporation, rainfall, wind speed and solar radiation) parameters were measured over a 2-year period in a typical AWR located in south-eastern Spain. In the first year, the AWR remained uncovered and the behaviour was quasi-isothermal. In the second year, installing a SSCC induced a thermal gradient in the water that reached a maximum temperature difference of 12 °C during summer. The lack of turbulence under the cover and the reduction in photosynthesis (95% reduction of chlorophyll-a) reduced the concentration of dissolved oxygen to 1.5 mg L−1, and turbidity from 40 NTU at installation to less than 1 NTU. The positive balance between rainfall and evaporation during the second year reduced the electrical conductivity of the water by 8.2%. The improvement in water quality associated with the installation of a SSCC increases the efficiency of drip irrigation systems by reducing the water filtering requirements, the likelihood of emitter clogging, and the risk of irrigation-induced salinity.

The Economic Impact of Water Evaporation Losses from Water Reservoirs in the Segura Basin, SE Spain

In this paper we assess the economic impact of evaporation losses from great dams (GDs) and on-farm agricultural water reservoirs (AWRs) in the semi-arid Segura River basin, SE Spain. Evaporation losses from water reservoirs reduce the high water use efficiency reached in agriculture by means of other techniques such as well-built water pipes or drip irrigation and have a substantial economic impact. Evaporation losses have been calculated using Class-A pan evaporation data and pan coefficients, whereas their economic impact has been assessed using an economic mathematical programming model that simulates land and water allocation in the different irrigated areas of the basin. Our results show that annual evaporation from GDs and AWRs represents 8.7% of the water currently available for irrigation in the Segura basin. The economic impact of such losses has been estimated in a reduction of 6.3% of the value of agricultural production and 5.4% of the farm net margin. As less water is effectively available for farmers the basin’s irrigated area is reduced in a 7.5%. This impact is greater, in both absolute and relative terms, in the areas accommodating the most intensive and profitable irrigated agriculture. The applied methodology and results could be useful to regional water agencies and collective irrigation schemes for future planning and management, including the assessment of alternatives for reducing evaporation from reservoirs.

STEATITIS IN EGRETS AND HERONS FROM JAPAN

More than 70 egrets and herons were found sick or dead at an agricultural water reservoir in Kanagawa Prefecture, Japan between September and October 2008. The birds showed weakness, lethargy, and inability to fly before death. Postmortem findings included large amounts of firm subcutaneous and cavitary fat comprised of necrotic adipose tissues with infiltrates of heterophils and macrophages. The birds were diagnosed with steatitis on the basis of the gross lesions and histopathology. Egrets with steatitis had low blood levels of vitamin E. High counts of cyanobacteria (Microcystis aeruginosa) were found in the reservoir concurrent with the outbreak of steatitis. No microcystin was detected in the reservoir water or the livers from the egrets. This is the first report of steatitis in wild birds in Japan.

Energy balance and evaporation loss of an irrigation reservoir equipped with a suspended cover in a semiarid climate (south-eastern Spain)

The main objective of this study was to assess the impact of a suspended cover on the evaporation loss of an agricultural water reservoir (AWR). To this aim, a detailed data collection was carried out in a typical AWR located in south-eastern Spain during 2 consecutive years. During the first year, the reservoir remained uncovered, while during the second year it was covered with a double black polyethylene (PE) shade cloth. On an annual scale, it was observed that the cover can provide a reduction of evaporation loss of 85%. Two approaches, energy balance and mass transfer, were used to analyse the effect of the cover on the evaporation process. Important modifications were observed on the magnitude, sign, annual trend and relative weight of the components of the energy balance. The changes were ascribed to the strong reduction of net radiation and to the substantial weight of the heat storage and sensible heat flux in the energy balance. A relevant finding was the contrast between the patterns of the annual evaporation curve for open-water and covered conditions. The mass transfer approach allowed discriminating between the wind- and radiation-shelter effects on the evaporation term. The reduction in water-to-air vapour deficit was the main factor explaining the high efficiency of the cover, whereas the reduction of the mass transfer coefficient was a modulating factor that accounted for the wind-shelter effect. Overall, both approaches provided a sound basis to describe and explain the physical mechanisms underlying the high performance of the tested cover. Copyright © 2010 John Wiley & Sons, Ltd.

Energy balance and evaporation loss of an agricultural reservoir in a semi‐arid climate (south‐eastern Spain)

AbstractA typical agricultural water reservoir (AWR) of 2400 m2 area and 5 m depth, located in a semi‐arid area (southern Spain), was surveyed on a daily basis for 1 year. The annual evaporation flux was 102·7 W m−2, equivalent to an evaporated water depth of 1310 mm year−1. The heat storage rate G exhibited a clear annual cycle with a peak gain in April (G ∼ 45 W m−2) and a peak loss in November (G ∼ 40 W m−2), leading to a marked annual hysteretic trend when evaporation (λE) was related to net radiation (Rn). λE was strongly correlated with the available energy A, representing 91% of the annual AWR energy loss. The sensible heat flux H accounted for the remaining 9%, leading to an annual Bowen ratio in the order of 0·10. The equilibrium and advective evaporation terms of the Penman formula represented 76 and 24%, respectively, of the total evaporation, corresponding to a annual value of the Priestley–Taylor (P–T) coefficient (α) of 1·32. The P–T coefficient presented a clear seasonal pattern, with a minimum of 1·23 (July) and a maximum of 1·65 (December), indicating that, during periods of limited available energy, AWR evaporation increased above the potential evaporation as a result of the advection process. Overall, the results stressed that accurate prediction of monthly evaporation by means of the P–T formula requires accounting for both the annual cycle of storage and the advective component. Some alternative approaches to estimating Rn, G and α are proposed and discussed. Copyright © 2009 John Wiley & Sons, Ltd.

Economic assessment of shade-cloth covers for agricultural irrigation reservoirs in a semi-arid climate

We assess the economics of investing in suspended shade-cloth covers (SSCCs) in agricultural water reservoirs (AWRs) to reduce evaporation losses and save water for irrigation in arid and semi-arid areas. In particular, we examine the use of SSCCs in the Segura River Basin (southeastern Spain). The decision to install a cover depends on the potential evaporation losses, reservoir characteristics, cover effectiveness, the value of water, filtration requirements, water salinity, government subsidies and the installation, operation and maintenance costs. The economic viability of the investment increases with the value of the saved water, i.e., with water scarcity, and is greater when water quality is poor. Hence SSCCs can be helpful in arid and semi-arid regions facing water shortages and water quality problems. The farm-level decision to install a cover depends largely on the cost of purchasing water, when water is generally available, and the profit from increased crop production or enlarged farmlands, when water is scarce.

Regional assessment of evaporation from agricultural irrigation reservoirs in a semiarid climate

The aim of this study was to assess the magnitude of evaporation loss from the agricultural water reservoirs (AWRs) for irrigation at a regional scale and to analyze its impact on water storage efficiency. To this end, we identified the extant AWRs for irrigation in the Segura River Basin (SRB) in southeastern Spain, and calculated the water loss from each AWR per month and year. In order to accomplish this, we determined the monthly and yearly values of the pan coefficient, K p, taking into account the geometric dimensions (area and depth) of the AWRs and local climate conditions through a function of air vapour pressure deficit (VPD). AWR areas were identified by interpreting aerial images, while climate conditions were assessed using daily meteorological data obtained from 74 automated agro-meteorological stations located in irrigated areas. Regional evaporation losses were estimated using aggregation GIS techniques. A total of 14,145 AWRs covering 4901 ha were identified, which represents 0.26 and 1.81% of the total area of SRB and the irrigated land, respectively. Results indicated that annual water loss at a basin scale reaches 58.5 × 10 6 m 3, which corresponds to 1.404 m of water depth over the flooded area and to 8.3% of irrigation water use in the basin. This quantity is higher than the industrial demand and similar to the environmental demand, and is equivalent to 27% of the domestic water use in a region with approximately two million inhabitants. The method used, based on annual K p, appears the most straightforward to assess regional evaporative losses from AWRs, and can be extended to other regions and climates, provided that the VPD-dependent function that gives the pan coefficient is available.

A novel approach for estimating the pan coefficient of irrigation water reservoirs: Application to South Eastern Spain

The evaporation rate ( E) and pan coefficient ( K p) of agricultural water reservoirs for irrigation (AWRIs) were determined using a novel approach based on a reservoir energy balance model and measurements of pan evaporation. The model, previously developed and validated for an insulated Class-A pan, was upscaled to the case of AWRIs by introducing a new formulation of the wind function combining the Brutsaert and Harbeck formulae. The model was run for different combinations of area ( S) and depth ( D) at several locations of the Segura River Basin (South Eastern Spain) where routine pan evaporation measurements ( E p) were available. The monthly and annual K p values were derived from the simulation runs as the ratio of the simulated AWRI evaporation to the measured pan evaporation, E/ E p. Results at a monthly scale indicated that D was the main factor affecting the evolution and the value of the surface temperature and evaporation rate, while S, for a given value of D, had only a small influence. Monthly K p varied significantly through the year, the variation range being larger for deep AWRIs (0.5 < K p < 1.5) than for shallow ones (0.8 < K p < 1.2). At a yearly scale, K p was found nearly constant for a given AWRI, with small inter-annual variations. Annual K p varied in the range 0.76 ( S = 50,000 m 2) to 0.86 ( S = 500 m 2), depending primarily on S, and to a lesser extent, on the vapour pressure deficit measured at the location. Empirical formulae allowing to predict annual K p as a function of S and vapour pressure deficit were proposed. It was concluded that the proposed modelling approach can be applied to accurately estimate values of K p in AWRIs at regional scale, taking into account the influence of reservoir dimensions and local climate conditions. Its application under South Eastern Spain conditions supplied the monthly and annual values of K p to be used under similar Mediterranean semi-arid climates.