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1
Sołtysiak, Marek, and Michał Rakoczy. "An overview of the experimental research use of lysimeters." Environmental & Socio-economic Studies 7, no. 2 (June 1, 2019): 49–56. http://dx.doi.org/10.2478/environ-2019-0012.
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Abstract The lysimeter is most often defined as a box filled with soil with an intact structure for measuring the amount of infiltration and evapotranspiration in natural conditions. At the bottom of the device there is an outflow for atmospheric precipitation water infiltrating to a measuring container. Lysimeter studies are included in the group of dynamic leaching tests in which the leaching solution is added in a specified volume over a specific period of time. Lysimeter studies find applications in, amongst others, agrotechnics, hydrogeology and geochemistry. Lysimeter tests may vary in terms of the type of soil used (anthropogenic soil, natural soil), sample size, leaching solution, duration of the research and the purpose for conducting it. Lysimeter experiments provide more accurate results for leaching tests compared with static leaching tests. Unlike several-day tests, they should last for at least a year. There are about 2,500 lysimeters installed in nearly 200 stations around Europe. The vast majority of these (84%) are non-weighing lysimeters. There are a few challenges for lysimeter research mostly connected with the construction of the lysimeter, estimating leaching results and calibrating numerical transport models with data obtained from lysimeters. This review is devoted to the analysis of the principal types of lysimeters described in the literature within the context of their application. The aim of this study is to highlight the role of lysimeters in leaching studies.
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SHAHRAJABIAN, M. H., M. KHOSHKHARAM, A. SOLEYMANI, W. SUN, and Q. CHENG. "CONSIDERING SOIL WATER CONTENT, NUTRIENTS MOVEMENT, PHENOLOGY AND PLANT GROWTH WITH REFERENCE TO DEVELOPMENT OF FUNCTIONAL FOODS IN A LYSIMETER STUDY." Cercetari Agronomice in Moldova 53, no. 1 (2020): 121–35. http://dx.doi.org/10.46909/cerce-2020-010.
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Lysimeter is equipped with mechanisms for weighing by load cells enable automated measurements, and the signals resulting from weight changes in the system due to evaporation that are generally recorded in a data acquisition system. According to methods of measuring water content, lysimeters may be divided into weighing lysimeter and non-weighing lysimeter. The weighing lysimeters provide scientists the basic information for research related to evapotranspiration, and they are commonly divided into two types, continuous weighing and intermittent weighing. Weighing lysimeters have been used to quantify precipitation (P) not only in the form of rain or snow, but also dew, fog and rime, and also to determine actual evapotranspiration (ET). Compared to laboratory experiments, out-door lysimeter studies have advantages, like being closer to field environment conditions, it is possible to grow plants and therefore to study the fate of chemicals in soil/plant systems, transformations and leaching. The limitations are costy, which depend on design, variable experimental conditions, such as environmental/ climatic parameters, which are normally not controlled, the soil spatial variability is normally less, they are not suitable for every plant species and even every soil type. The objective of lysimeter is defining the crop coefficient (Kc), which used to convert ETr into equivalent crop evapotranpiration (ETc) values, and determing agronomical characteristics of crops, which are planted in the field of lysimeter. The duration of a lysimeter study is determined by the objective of the study, but for different crops, it should normally be at least two years. Weighing lysimeters using load cells have the advantage of measuring the water balance in the soil over a short time and with good accuracy. Precipitation should be recorded daily at the lysimeter site. All weather data like air temperature, solar radiation, humidity and potential evporation should be obtained onsite, and the frequency and time of measurements should be at least daily.
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López-Urrea, Ramón, José Jesús Pardo, Llanos Simón, Ángel Martínez-Romero, Francisco Montoya, José María Tarjuelo, and Alfonso Domínguez. "Assessing a Removable Mini-Lysimeter for Monitoring Crop Evapotranspiration Using a Well-Established Large Weighing Lysimeter: A Case Study for Barley and Potato." Agronomy 11, no. 10 (October 15, 2021): 2067. http://dx.doi.org/10.3390/agronomy11102067.
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Further research is required on the measurement of crop evapotranspiration (ETc) to produce new or updated crop coefficients for a large number of crops using accurate weighing lysimeters. However, large weighing lysimeters are sometimes expensive and are not portable, and different prototypes of small-sized lysimeters may be a feasible alternative. This study evaluated the performance of a removable mini-lysimeter model to measure ETc and derive crop coefficients using a long-established large precision weighing lysimeter over a two-year period. The study was conducted during the 2017 and 2018 barley and potato growing seasons, respectively, at a lysimeter facility located in Albacete (southeast Spain). ETc values were determined using daily mass change in the lysimeters. Irrigation was managed to avoid any water stress. In the barley season, the mini-lysimeter underestimated the seasonal ETc by 2%, the resulting errors in barley ETc estimation were an MBE of −0.070 mm d−1 and an RMSE of ±0.289 mm d−1. In the potato season, the mini-lysimeter overestimated the cumulative ETc by 5%, the resulting errors in potato ETc measurement were an MBE of 0.222 mm d−1 and an RMSE of ±0.497 mm d−1. The goodness of fit indicators showed a good agreement between the large and mini-lysimeter barley and potato ETc measurements at daily time step. Single (Kc) and dual crop coefficients (Kcb, crop transpiration + Ke, soil evaporation) were derived from the lysimeter measurements, the grass reference evapotranspiration (ETo) and the FAO56 dual Kc approach; after temperate standard climate adjustment, mid-season values were Kc mid (std) = 1.05 and Kcb mid (std) = 1.00 for barley; and Kc mid (std) = 1.06 and Kcb mid (std) = 1.02 for potato. The good agreement found between Kcb values and fc will allow barley and potato water requirements to be accurately estimated.
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Cameron, KC, DF Harrison, NP Smith, and CDA Mclay. "A method to prevent edge-flow in undisturbed soil cores and lysimeters." Soil Research 28, no. 6 (1990): 879. http://dx.doi.org/10.1071/sr9900879.
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This study shows that edge-flow of water and solutes between soil samples and lysimeter or permeameter casings can result in significant errors in the measurement of hydraulic conductivity and leaching rates. A new lysimeter design and technique are described which prevent edge-flow from occurring. Liquefied petrolatum is injected into an annular gap between the soil and the lysimeter casing producing a watertight seal. Water and solute movement in the sealed lysimeter is therefore confined within the soil monolith and no edge-flow occurs. Hydraulic conductivity and solute leaching rates are significantly lower in sealed lysimeters compared with unsealed ones.
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Fernando, Salani U., Lakshman Galagedara, Mano Krishnapillai, and Chad W. Cuss. "Lysimeter Sampling System for Optimal Determination of Trace Elements in Soil Solutions." Water 15, no. 18 (September 16, 2023): 3277. http://dx.doi.org/10.3390/w15183277.
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Understanding trace element (TE) composition and behavior in soil solution is extremely important for assessing ecological and human health impacts. Using lysimeters to collect soil solution with minimum alteration to the in situ phase distribution and concentration of TEs will facilitate a more accurate assessment. However, different lysimeter materials and sampling conditions may lead to vastly different results, demonstrating the need for the optimal choice of lysimeter depending upon environmental conditions. There is no general agreement or overview discussing the best lysimeter type and sampling system to use under various conditions. This review provides a critical summary of various lysimeters that can be used to collect soil solutions for the analysis of TEs and thereby provides key guidance for developing the best lysimeter sampling system for conditions and research questions of interest. This includes a range of aspects related to lysimeters, such as different types and materials, the basic principles of design and operation, advantages and disadvantages, challenges and limitations, techniques for cleaning and pretreatment, correct installation procedures, the influence of soil physical and chemical properties on sampling, and existing research gaps within this field.
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Peters, A., and W. Durner. "Large zero-tension plate lysimeters for soil water and solute collection in undisturbed soils." Hydrology and Earth System Sciences Discussions 6, no. 3 (June 30, 2009): 4637–69. http://dx.doi.org/10.5194/hessd-6-4637-2009.
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Abstract. Water collection from undisturbed unsaturated soils to estimate in situ water and solute fluxes in the field is a challenge, in particular if soils are heterogeneous. Large sampling devices are required if preferential flow paths are present. We present a modular plate system that allows installation of large zero-tension lysimeter plates under undisturbed soils in the field. To investigate the influence of the lysimeter on the water flow field in the soil, a numerical 2-D simulation study was conducted for homogeneous soils with uni- and bimodal pore-size distributions and stochastic Miller-Miller heterogeneity. The collection efficiency was found to be highly dependent on the hydraulic functions, infiltration rate, and lysimeter size, and was furthermore affected by the degree of heterogeneity. In homogeneous soils with high saturated conductivities the devices perform poorly and even large lysimeters (width 250 cm) can be bypassed by the soil water. Heterogeneities of soil hydraulic properties result into a network of flow channels that enhance the sampling efficiency of the lysimeter plates. Solute breakthrough into zero-tension lysimeter occurs slightly retarded as compared to the free soil, but concentrations in the collected water are similar to the mean flux concentration in the undisturbed soil. To validate the results from the numerical study, a dual tracer study with seven lysimeters of 1.25×1.25 m area was conducted in the field. Three lysimeters were installed underneath a 1.2 m filling of contaminated silty sand, the others deeper in the undisturbed soil. The lysimeters directly underneath the filled soil material collected water with a collection efficiency of 45%. The deeper lysimeters did not collect any water. The arrival of the tracers showed that almost all collected water came from preferential flow paths.
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Peters, A., and W. Durner. "Large zero-tension plate lysimeters for soil water and solute collection in undisturbed soils." Hydrology and Earth System Sciences 13, no. 9 (September 18, 2009): 1671–83. http://dx.doi.org/10.5194/hess-13-1671-2009.
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Abstract. Water collection from undisturbed unsaturated soils to estimate in situ water and solute fluxes in the field is a challenge, in particular if soils are heterogeneous. Large sampling devices are required if preferential flow paths are present. We present a modular plate system that allows installation of large zero-tension lysimeter plates under undisturbed soils in the field. To investigate the influence of the lysimeter on the water flow field in the soil, a numerical 2-D simulation study was conducted for homogeneous soils with uni- and bimodal pore-size distributions and stochastic Miller-Miller heterogeneity. The collection efficiency was found to be highly dependent on the hydraulic functions, infiltration rate, and lysimeter size, and was furthermore affected by the degree of heterogeneity. In homogeneous soils with high saturated conductivities the devices perform poorly and even large lysimeters (width 250 cm) can be bypassed by the soil water. Heterogeneities of soil hydraulic properties result into a network of flow channels that enhance the sampling efficiency of the lysimeter plates. Solute breakthrough into zero-tension lysimeter occurs slightly retarded as compared to the free soil, but concentrations in the collected water are similar to the mean flux concentration in the undisturbed soil. To validate the results from the numerical study, a dual tracer study with seven lysimeters of 1.25×1.25 m area was conducted in the field. Three lysimeters were installed underneath a 1.2 m filling of contaminated silty sand, the others deeper in the undisturbed soil. The lysimeters directly underneath the filled soil material collected water with a collection efficiency of 45%. The deeper lysimeters did not collect any water. The arrival of the tracers showed that almost all collected water came from preferential flow paths.
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Gazula, Aparna, Eric Simonne, Michael Dukes, George Hochmuth, Bob Hochmuth, and David Studstill. "OPTIMIZATION OF DRAINAGE LYSIMETER DESIGN FOR FIELD DETERMINATION OF NUTRIENT LOADS." HortScience 41, no. 3 (June 2006): 508D—508. http://dx.doi.org/10.21273/hortsci.41.3.508d.
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Collecting leachate from lysimeters installed in the field below vegetable fields may be used to quantify the amount of nitrogen released into the environment. Because limited information exists on the optimal design type and on the effect of design components on lysimeter performance, the objective of this study were to identify existing designs and their limits, assess cost of design, and test selected designs. Ideally, lysimeters should be wide enough to collect all the water draining, long enough to reflect the plant-to-plant variability, durable enough to resist degradation, deep enough to allow for cultural practices and prevent root intrusion, have a simple design, be made of widely available materials, and be cost-effective. Also, lysimeters should not restrict gravity flow thereby resulting in a perched water table. Previous study done with a group of free-drainage lysimeters (1-m-long, 45-cm-wide, installed 45-cm-deep) under a tomato-pumpkin-rye cropping sequence resulted in variable frequency of collection and volume of leachate collected (CV of load = 170%). Improving existing design may be done by increasing the length of collection, lining the lysimeter with gravel, limiting the depth of installation, and/or breaking water tension with a fiberglass wick. Individual lysimeter cost was estimated between $56 to $84 and required 9 to 14 manhours. for construction and installation. Costs on labor may be reduced when large numbers of lysimeters are built. Labor needed for sampling 24 lysimeters was 8 man-hr/sampling date. Because load may occur after a crop, lysimeter monitoring and sampling should be done year round.
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McCauley, Dalyn, Alexander Levin, and Lloyd Nackley. "Reviewing Mini-lysimeter Controlled Irrigation in Container Crop Systems." HortTechnology 31, no. 6 (December 2021): 634–41. http://dx.doi.org/10.21273/horttech04826-21.
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This study reviews how mini-lysimeters have been used effectively to optimize irrigation control in container horticulture production. Lysimeters are devices that measure evapotranspiration (ET) from the water balance of a fixed soil volume. The primary components of lysimeter-controlled irrigation are load cell sensors, a multiplexer, a data logger, a controller, and solenoid valves. The two common mini-lysimeter systems are platform lysimeters and suspension lysimeters. In these systems, a bending-beam single-point load cell is fastened between two plates, and a container is placed directly on the top platform. Platform lysimeters are commonly used for smaller pot sizes, and suspension lysimeters have been used for large shade trees up to 2.8 m tall and weighing 225 kg. Mini-lysimeters have been used for decades to calibrate ET models and create on-demand irrigation control programs that replenish plant daily water use or maintain deficit conditions. Research has demonstrated that lysimeter-based irrigation can respond more effectively to seasonal and diurnal variations in water demand, increasing irrigation cycles when evaporative demand is high, and decreasing irrigation cycles when demand is low. A strength of these systems is that for containerized plants, such as nursery production systems, mini-lysimeters capture whole-plant water use, which presents a more holistic measure compared with soil moisture sensors or leaf moisture sensors.
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Isch, Arnaud, Denis Montenach, Frederic Hammel, Philippe Ackerer, and Yves Coquet. "A Comparative Study of Water and Bromide Transport in a Bare Loam Soil Using Lysimeters and Field Plots." Water 11, no. 6 (June 8, 2019): 1199. http://dx.doi.org/10.3390/w11061199.
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The purpose of this methodological study was to test whether similar soil hydraulic and solute transport properties could be estimated from field plots and lysimeter measurements. The transport of water and bromide (as an inert conservative solute tracer) in three bare field plots and in six bare soil lysimeters were compared. Daily readings of matric head and volumetric water content in the lysimeters showed a profile that was increasingly humid with depth. The hydrodynamic parameters optimized with HYDRUS-1D provided an accurate description of the experimental data for both the field plots and the lysimeters. However, bromide transport in the lysimeters was influenced by preferential transport, which required the use of the mobile/immobile water (MIM) model to suitably describe the experimental data. Water and solute transport observed in the field plots was not accurately described when using parameters optimized with lysimeter data (cross-simulation), and vice versa. The soil’s return to atmospheric pressure at the bottom of the lysimeter and differences in tillage practices between the two set-ups had a strong impact on soil water dynamics. The preferential flow of bromide observed in the lysimeters prevented an accurate simulation of solute transport in field plots using the mean optimized parameters on lysimeters and vice versa.
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Gebler, S., H. J. Hendricks Franssen, T. Pütz, H. Post, M. Schmidt, and H. Vereecken. "Actual evapotranspiration and precipitation measured by lysimeters: a comparison with eddy covariance and tipping bucket." Hydrology and Earth System Sciences 19, no. 5 (May 5, 2015): 2145–61. http://dx.doi.org/10.5194/hess-19-2145-2015.
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Abstract. This study compares actual evapotranspiration (ETa) measurements by a set of six weighable lysimeters, ETa estimates obtained with the eddy covariance (EC) method, and evapotranspiration calculated with the full-form Penman–Monteith equation (ETPM) for the Rollesbroich site in the Eifel (western Germany). The comparison of ETa measured by EC (including correction of the energy balance deficit) and by lysimeters is rarely reported in the literature and allows more insight into the performance of both methods. An evaluation of ETa for the two methods for the year 2012 shows a good agreement with a total difference of 3.8% (19 mm) between the ETa estimates. The highest agreement and smallest relative differences (< 8%) on a monthly basis between both methods are found in summer. ETa was close to ETPM, indicating that ET was energy limited and not limited by water availability. ETa differences between lysimeter and EC were mainly related to differences in grass height caused by harvest and the EC footprint. The lysimeter data were also used to estimate precipitation amounts in combination with a filter algorithm for the high-precision lysimeters recently introduced by Peters et al. (2014). The estimated precipitation amounts from the lysimeter data differ significantly from precipitation amounts recorded with a standard rain gauge at the Rollesbroich test site. For the complete year 2012 the lysimeter records show a 16 % higher precipitation amount than the tipping bucket. After a correction of the tipping bucket measurements by the method of Richter (1995) this amount was reduced to 3%. With the help of an on-site camera the precipitation measurements of the lysimeters were analyzed in more detail. It was found that the lysimeters record more precipitation than the tipping bucket, in part related to the detection of rime and dew, which contribute 17% to the yearly difference between both methods. In addition, fog and drizzle explain an additional 5.5% of the total difference. Larger differences are also recorded for snow and sleet situations. During snowfall, the tipping bucket device underestimated precipitation severely, and these situations contributed also 7.9% to the total difference. However, 36% of the total yearly difference was associated with snow cover without apparent snowfall, and under these conditions snow bridges and snow drift seem to explain the strong overestimation of precipitation by the lysimeter. The remaining precipitation difference (about 33%) could not be explained and did not show a clear relation to wind speed. The variation of the individual lysimeters devices compared to the lysimeter mean are small, showing variations up to 3% for precipitation and 8% for evapotranspiration.
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Gebler, S., H. J. Hendricks Franssen, T. Pütz, H. Post, M. Schmidt, and H. Vereecken. "Actual evapotranspiration and precipitation measured by lysimeters: a comparison with eddy covariance and tipping bucket." Hydrology and Earth System Sciences Discussions 11, no. 12 (December 17, 2014): 13797–841. http://dx.doi.org/10.5194/hessd-11-13797-2014.
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Abstract. This study compares actual evapotranspiration (ETa) measurements by a set of six weighable lysimeters, ETa estimates obtained with the eddy covariance (EC) method, and potential crop evapotranspiration according to FAO (ETc-FAO) for the Rollesbroich site in the Eifel (Western Germany). The comparison of ETa measured by EC (including correction of the energy balance deficit) and by lysimeters is rarely reported in literature and allows more insight into the performance of both methods. An evaluation of ETa for the two methods for the year 2012 shows a good agreement with a total difference of 3.8% (19 mm) between the ETa estimates. The highest agreement and smallest relative differences (<8%) on monthly basis between both methods are found in summer. ETa was close to ETc-FAO, indicating that ET was energy limited and not limited by water availability. ETa differences between lysimeter, ETc-FAO, and EC were mainly related to differences in grass height caused by harvesting management and the EC footprint. The lysimeter data were also used to estimate precipitation amounts in combination with a filter algorithm for high precision lysimeters recently introduced by Peters et al. (2014). The estimated precipitation amounts from the lysimeter data show significant differences compared to the precipitation amounts recorded with a standard rain gauge at the Rollesbroich test site. For the complete year 2012 the lysimeter records show a 16% higher precipitation amount than the tipping bucket. With the help of an on-site camera the precipitation measurements of the lysimeters were analyzed in more detail. It was found that the lysimeters record more precipitation than the tipping bucket in part related to the detection of rime and dew, which contributes 17% to the yearly difference between both methods. In addition, fog and drizzle explain an additional 5.5% of the total difference. Larger differences are also recorded for snow and sleet situations. During snowfall, the tipping bucket device underestimated precipitation severely and these situations contributed also 7.9% to the total difference. However, 36% of the total yearly difference was associated to snow cover without apparent snowfall and under these conditions snow bridges and snow drift seem to explain the strong underestimation of precipitation by the lysimeter. The remaining precipitation difference (about 33%) could not be explained, and did not show a clear relation with wind speed. The variations of the individual lysimeters devices compared to the lysimeter mean of 2012 are small showing variations up to 3% for precipitation and 8% for evapotranspiration.
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Piccinni, Giovanni, Daniel I. Leskovar, and Thomas Marek. "Determination of Crop Coefficients (Kc) and Water Use of Spinach and Onion." HortScience 40, no. 4 (July 2005): 1095C—1095. http://dx.doi.org/10.21273/hortsci.40.4.1095c.
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Lysimeters are used to measure real-time water use during the growing season. By relating the water use of a specific crop to a well-watered reference crop, such as alfalfa or grass, crop coefficients (Kc) can be developed to assist in predicting accurate crop needs using available meteorological data. Reference evapotranspiration can be obtained from several weather networks; however, without crop coefficients for specific crops, this information is only useful for grass. Three weighing lysimeters, consisting of undisturbed 1.5 m × 2.0 m area by 2.2-m depth cores of soil, comprise the Texas A&M Research and Extension Center–Uvalde lysimeter facility. Two lysimeters, weighing around 15,000 kg, have been placed beneath a linear LEPA irrigation system and used in field production. A third lysimeter measures reference ET values (ETo) and is located in a grassed area near the field lysimeters irrigated by subsurface drip irrigation system. Spinach was grown in one of the two crop lysimeters while onion was grown in the second lysimeter. Daily water use was measured on 5-min intervals. Results show the possibility of saving ≈61 to 74 million m3 of water per year in the irrigated farms of the Edwards aquifer region if proper irrigation management techniques are implemented in conjunction with the newly developed crop coefficients. Crop water requirements, Kc determination, and comparison to existing FAO Kc values will be discussed.
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Lyles, Brad F., Brad D. Sion, David Page, Jackson B. Crews, Eric V. McDonald, and Mark B. Hausner. "Closing the Water Balance with a Precision Small-Scale Field Lysimeter." Sensors 24, no. 7 (March 22, 2024): 2039. http://dx.doi.org/10.3390/s24072039.
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We developed a set of two precision, small-scale, water balance lysimeters to provide accurate measurements of bare soil evaporation. Each lysimeter comprises a soil tank, a balance assembly with load cell, a wicking drainage system, and a stilling well to measure drained water. Fiberglass wicks installed at the bottom of the soil tanks provide −60 cm of tension to the base of the soil column, and soil water drainage is quantified to close the water balance within the lysimeter. The calibrated lysimeters return mass changes with uncertainties ranging from 3 to 8 g, corresponding to uncertainties of 0.02–0.05 mm of water. Installed at a semi-arid site in northern Nevada, the two lysimeters are filled with uniform construction sand and silt loam. Over a six-month pilot observation period, bare soil evaporation rates of 0.19 and 0.40 mm/day were measured for the construction sand and silt loam, respectively, which is consistent with meteorological data and models of potential evapotranspiration at the site. The design of the lysimeter can be adapted to specific research goals or site restrictions, and these instruments can contribute significantly to our ability to close the soil water balance.
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P. K. KINGRA and R. K. MAHEY. "Comparative evaluation of different methods to compute evapotranspiration at different phenological stages in wheat." Journal of Agrometeorology 11, no. 2 (December 1, 2009): 102–8. http://dx.doi.org/10.54386/jam.v11i2.1234.
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Evapotranspiration of wheat crop was estimated using different methods viz. lysimeter, USDA Open pan evaporimeter, empirical methods, combination approach and soil water evaporation model. The field experiment was conducted during rabi 2006-07 and 2007-08 with two weighing type lysimeters located at the research farm, Punjab Agricultural University, Ludhiana. Among different methods of ET estimation, Papadakis method computed highest rate of PET followed by Hamon and modified Penman method whereas modified soil evaporation model, Thornthwaite, Blaney-Criddle and Stephans & Stewart methods produced lower values of PET as compared to lysimeter ET and open pan evaporation. Modified Jensen & Haise method estimated PET values (346 and 361 mm) closest to lysimeter ET (340 and 341 mm) and open pan evaporation (360 and 432 mm) respectively, for two seasons. PET computed by Blaney-Criddle method showed very good correlation with Lysimeter ET (0.90).
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Sanches, Arthur C., Débora P. de Souza, Fernando C. Mendonça, and Rodolfo G. Maffei. "Construction and calibration of weighing lysimeters with an automated drainage system." Revista Brasileira de Engenharia Agrícola e Ambiental 21, no. 7 (July 2017): 505–9. http://dx.doi.org/10.1590/1807-1929/agriambi.v21n7p505-509.
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ABSTRACT Quantification of the drained volume is one of the difficulties involved in using weighing lysimeters. Typically, this volume is measured by accessing a moat at the base of a lysimeter. However, it is not feasible to install the moat in small devices. Thus, the aim of this study involves developing, installing, calibrating, and checking the efficiency of small weighing lysimeters with automated drainage systems to test their functionality in field conditions. Each lysimeter is composed of a round PVC water tank with a diameter of 1.22 m and a depth of 0.58 m that is placed over a metal frame with three electronic load cells with the nominal capacity of each cell corresponding to 500 kg. The drainage system is composed of a small reservoir with a volume of 10 L, a weighing structure composed of a load cell with a nominal capacity of 30 kg, and an automatic solenoid valve driven by a device coupled to a data logger that records the data from the lysimeter and from the drainage system. Two calibrations are performed for the lysimeter as well as the drainage system to obtain equations with significant correlations (R2 > 0.9999). The drainage system was activated several times during the tests after receiving approximately 63.4 L of water from rainfall, and this in turn indicated a good performance.
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Titus, B. D., D. G. O. Kingston, C. M. Pitt, and M. K. Mahendrappa. "A lysimeter system for monitoring soil solution chemistry." Canadian Journal of Soil Science 80, no. 1 (February 1, 2000): 219–26. http://dx.doi.org/10.4141/s99-018.
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In northern temperate and boreal zones, long-term sampling of the soil solution using lysimeter systems requires (i) a lysimeter that can be installed with a minimum of soil disturbance, (ii) a lysimeter that is small enough to install in stony soil but large enough to representatively sample the soil solution, (iii) a system with a constant tension that integrates soil solution sample collection over time, and (iv) a system that will not break under freezing conditions. A lysimeter system that meets these requirements was designed, and consists of a lysimeter (a fritted glass plate mounted on a glass casing) connected in series to a sample bottle and a tension-generating unit. The glass casing of the lysimeter has two ports: a drainage port for continuous flow of soil solution to the sample bottle, and an access port that can be used (i) for air entry to facilitate complete sample retrieval, (ii) for cleaning, (iii) for re-wetting the fritted glass plate, or (iv) for winterizing the lysimeter with alcohol. A 1-m hanging water column was used to supply a constant tension of approximately 10 kPa. A potential 93% efficiency rate of sample collection can be achieved, and the systems are capable of sampling soil solution beneath organic horizons, as well as in the rooting zone of mineral horizons. The system is presently being used to evaluate the effects of different harvesting and silvicultural treatments on nutrient cycling processes in the soil. Almost 700 of these lysimeter systems are in use in the Atlantic provinces of Canada. The lysimeters have been functioning satisfactorily for over 10 yr and are suitable for long-term monitoring of the soil solution. Key words: Lysimeter design, soil monitoring methodology, nutrient cycling
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Evett, Steven R., Gary W. Marek, Paul D. Colaizzi, Brice B. Ruthardt, and Karen S. Copeland. "A Subsurface Drip Irrigation System for Weighing Lysimetry." Applied Engineering in Agriculture 34, no. 1 (2018): 213–21. http://dx.doi.org/10.13031/aea.12597.
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Abstract. Large, precision weighing lysimeters can have accuracies as good as 0.04 mm equivalent depth of water, adequate for hourly and even half-hourly determinations of evapotranspiration (ET) rate from crops. Such data are important for testing and improving simulation models of the complex interactions of surface water and energy balances, soil physics, plant growth, and biophysics that determine crop ET in response to rapid microclimate dynamics. When crops are irrigated with sprinkler systems or other rapid additions of water, the irrigation event is typically short enough that not much ET data are compromised by the lysimeter mass change due to irrigation. In contrast, subsurface drip irrigation (SDI) systems may take many hours to apply an irrigation, during which time the lysimeter mass change is affected by both ET rate and irrigation application rate. Given that irrigation application rate can be affected by pressure dynamics of the irrigation system, emitter clogging and water viscosity changes with temperature over several-hour periods, it can be difficult to impossible to separate the ET signal from the interference of the irrigation application. The inaccuracies in the data can be important, particularly for comparisons of sprinkler and SDI systems, since they are of the order of 8 to 10% of daily ET. We developed an SDI irrigation system to apply irrigations of up to 50 mm to large weighing lysimeters while limiting the period of lysimeter mass change due to irrigation delivery to approximately ten minutes by storing the water needed for irrigation in tanks suspended from the lysimeter weighing system. The system applied water at the same rate as the SDI system in the surrounding field, allowed irrigation over periods of any duration, but often exceeding 12 h, without directly affecting lysimeter mass change and the accuracy of ET rate determinations, and allowed irrigation overnight without compromising lysimeter daily ET measurements. Errors in lysimeter ET measurements using the previous SDI system, which was directly connected to the field irrigation system, were up to 10% of daily ET compared with negligible error using the new system. Errors using the previous, directly connected, SDI system varied over time due to variable system pressure, and possibly due to water temperature (viscosity) changes and emitter clogging. With the new system, all of the water transferred to the lysimeter weighing system was eventually applied by the SDI system regardless of temperature, pressure, or emitter clogging. Differences between planned and applied irrigation depth were less than 2% over the irrigation season. Keywords: Evapotranspiration, ET, Subsurface drip irrigation, SDI, Weighing lysimeter.
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Wegehenkel, Martin, and Horst H. Gerke. "Water table effects on measured and simulated fluxes in weighing lysimeters for differently-textured soils." Journal of Hydrology and Hydromechanics 63, no. 1 (March 1, 2015): 82–92. http://dx.doi.org/10.1515/johh-2015-0004.
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Abstract Weighing lysimeters can be used for studying the soil water balance and to analyse evapotranspiration (ET). However, not clear was the impact of the bottom boundary condition on lysimeter results and soil water movement. The objective was to analyse bottom boundary effects on the soil water balance. This analysis was carried out for lysimeters filled with fine- and coarse-textured soil monoliths by comparing simulated and measured data for lysimeters with a higher and a lower water table. The eight weighable lysimeters had a 1 m2 grass-covered surface and a depth of 1.5 m. The lysimeters contained four intact monoliths extracted from a sandy soil and four from a soil with a silty-clay texture. For two lysimeters of each soil, constant water tables were imposed at 135 cm and 210 cm depths. Evapotranspiration, change in soil water storage, and groundwater recharge were simulated for a 3-year period (1996 to 1998) using the Hydrus-1D software. Input data consisted of measured weather data and crop model-based simulated evaporation and transpiration. Snow cover and heat transport were simulated based on measured soil temperatures. Soil hydraulic parameter sets were estimated (i) from soil core data and (ii) based on texture data using ROSETTA pedotransfer approach. Simulated and measured outflow rates from the sandy soil matched for both parameter sets. For the sand lysimeters with the higher water table, only fast peak flow events observed on May 4, 1996 were not simulated adequately mainly because of differences between simulated and measured soil water storage caused by ET-induced soil water storage depletion. For the silty-clay soil, the simulations using the soil hydraulic parameters from retention data (i) were matching the lysimeter data except for the observed peak flows on May, 4, 1996, which here probably resulted from preferential flow. The higher water table at the lysimeter bottom resulted in higher drainage in comparison with the lysimeters with the lower water table. This increase was smaller for the finer-textured soil as compared to the coarser soil.
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Stanley, C. D., G. A. Clark, E. E. Albregts, and F. S. Zazueta. "USE OF FIELD-LOCATED DRAINAGE LYSIMETERS FOR THE DETERMINATION OF STRAWBERRY WATER REQUIREMENTS." HortScience 25, no. 9 (September 1990): 1097d—1097. http://dx.doi.org/10.21273/hortsci.25.9.1097d.
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Sixteen field-located drainage lysimeters (each 60 cm wide, 2.44 m long, 60 cm deep) designed specifically for determination of water requirements for fruiting strawberry production (season - Oct to April) were installed in 1986. Each lysimeter was equipped with individual micro-irrigation and drainage collection systems automated for minimal management input. Initially, computer control (using a low-cost microcomputer) was used to continuously check switching-tensiometers located in each lysimeter and apply irrigation water as needed, A drainage suction (-10 MPa) was applied continuously to simulate field drainage conditions. Manually-installed lysimeter covers were used to protect the plots from interference from rainfall when needed, Initial irrigation application treatments were set at four levels of soil moisture tension controlled by tensiometers and were measured using flow meters for each lysimeter. This paper will discuss problems that were experienced with the initial setup (difficulty in measuring actual application amounts, tensiometer and computer control, elimination of rainfall interference, uniformity of irrigation application, and salinity in the rooting zone) and the modifications (pressurized reservoir tanks, construction of motorized rain-out shelter, micro-irrigation emitters used, and fertilization program) which have been made to overcome them,
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Tall, Andrej, Branislav Kandra, Dana Pavelková, Sascha Reth, and Milan Gomboš. "Evaluation of precipitation measurements using a standard rain gauge in relation to data from a precision lysimeter." Journal of Hydrology and Hydromechanics 71, no. 4 (November 14, 2023): 413–24. http://dx.doi.org/10.2478/johh-2023-0024.
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Abstract The construction of modern lysimeters with a precise weighing system made it possible to achieve an unprecedented accuracy of precipitation measurement. This study compares two methods of measuring precipitation in the conditions of the humid continental climate of the Eastern Slovakian Lowland (Slovakia): measurement using a standard tipping-bucket rain gauge vs. precision weighable lysimeter. Data from the lysimeter were used as a reference measurement. The comparison period lasted four years (2019–2022). Only liquid rainfall was compared. The rain gauge was found to underestimate precipitation compared to the lysimeter. Cumulative precipitation for the entire monitored period captured by the rain gauge was 2.8% lower compared to lysimeter measurements. When comparing hourly and daily totals of precipitation and precipitation events, a very high degree of agreement was detected (r 2 > 0.99; RMSE from 0.22 to 0.51 mm h–1). A comparison based on precipitation intensity showed a decreasing trend in measurement accuracy with increasing precipitation intensity. This tendency has an exponential course. With increasing intensity of precipitation, increasing intensity of wind was also recorded. In order to correct measurement errors, simple correction method was proposed, which helped to partially eliminate the inaccuracies of the rain gauge measurement.
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GOYAL, POOJA, RAKESH SHARDA, MUKESH SIAG, and K. G. SINGH. "Development of an IoT based weighing type micro-lysimeter for soilless cultivation." Indian Journal of Agricultural Sciences 90, no. 10 (December 4, 2020): 1980–87. http://dx.doi.org/10.56093/ijas.v90i10.107978.
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In the present study, an attempt has been made to apply Internet of Things (IoT) for precise irrigation management. A weighing type micro-lysimeter based on IoT was developed to measure the amount of water consumed by the cucumber crop grown in soilless media under naturally ventilated greenhouse conditions at the Research Farm of Punjab Agricultural University, India. The developed system consisted of two components, i.e. hardware assembly and web-based application. The hardware assembly consists of load cells, a weight sensing module, i.e. HX711 module and a micro controller, i.e. arduino assembled in the control box of the weighing balance. A modular code was written in arduino to record the weight readings. The stored data in the microcontroller was sent to a web based application via wifi. The weight changes at the lysimeters due to irrigation, drainage and evapotranspiration were monitored in real time through an IoT platform, i.e. Thingspeak. Three lysimeters were placed at different locations to account for the slight variations in micro-climate within the greenhouse. The positive flux i.e. irrigation and negative flux, i.e. (leachate+ actual evapotranspiration (ETc)) from the lysimeter were derived from the IoT platform. Irrigation and leachate from the lysimeter was also measured manually to verify the accuracy of the readings obtained from the IoT platform. The study showed that IoT based lysimeters presents a reliable and convenient way to measure ETc as there was a good agreement (R2> 0.98) between irrigation component derived from IoT and actual irrigation applied.
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Dabrowska, Dominika, and Wojciech Rykala. "A Review of Lysimeter Experiments Carried Out on Municipal Landfill Waste." Toxics 9, no. 2 (February 2, 2021): 26. http://dx.doi.org/10.3390/toxics9020026.
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The groundwater risk assessment in the vicinity of landfill sites requires, among others, representative monitoring and testing for pollutants leaching from the waste. Lysimeter studies can serve as an example of dynamic leaching tests. However, due to the bacteriological composition of the municipal waste, they are rarely carried out. These tests allow for the proper design of the landfill protection system against migration of pollutants into the ground, assessment of bacteriological, biochemical and chemical risk for the groundwater, determination of the water balance of leachate as well as examination of the course of processes taking place in the waste landfill with a diversified access to oxygen. This paper addresses the issue of performing lysimeter studies on a sample of municipal waste in various scientific centers. It analyzes the size of lysimeters, their construction, the method of water supply, the duration of the experiment, the scope of research, and the purpose of lysimeter studies.
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Rücker, Andrea, Massimiliano Zappa, Stefan Boss, and Jana von Freyberg. "An Optimized Snowmelt Lysimeter System for Monitoring Melt Rates and Collecting Samples for Stable Water Isotope Analysis." Journal of Hydrology and Hydromechanics 67, no. 1 (March 1, 2019): 20–31. http://dx.doi.org/10.2478/johh-2018-0007.
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Abstract The contribution of snow meltwater to catchment streamflow can be quantified through hydrograph separation analyses for which stable water isotopes (18O, 2H) are used as environmental tracers. For this, the spatial and temporal variability of the isotopic composition of meltwater needs to be captured by the sampling method. This study compares an optimized snowmelt lysimeter system and an unheated precipitation collector with focus on their ability to capture snowmelt rates and the isotopic composition of snowmelt. The snowmelt lysimeter system consists of three individual unenclosed lysimeters at ground level with a surface of 0.14 m2 each. The unheated precipitation collector consists of a 30 cm-long, extended funnel with its orifice at 2.3 m above ground. Daily snowmelt samples were collected with both systems during two snowfall-snowmelt periods in 2016. The snowmelt lysimeter system provided more accurate measurements of natural melt rates and allowed for capturing the small-scale variability of snowmelt process at the plot scale, such as lateral meltwater flow from the surrounding snowpack. Because of the restricted volume of the extended funnel, daily melt rates from the unheated precipitation collector were up to 43% smaller compared to the snowmelt lysimeter system. Overall, both snowmelt collection methods captured the general temporal evolution of the isotopic signature in snowmelt.
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Meissner, R., J. Seeger, H. Rupp, and H. Balla. "Assessing the impact of agricultural land use changes on water quality." Water Science and Technology 40, no. 2 (July 1, 1999): 1–10. http://dx.doi.org/10.2166/wst.1999.0072.
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To study and predict environmental impacts of land use changes on water quality we conducted different types of lysimeter experiments. All of them are linked to representative experimental catchment areas in the field. This allows the verification and extrapolation of lysimeter results. The objective of this paper is to discuss a strategy for using and scaling-up of lysimeter results to a field and catchment scale. It will be shown that the N-loss determined with lysimeters falls within the variation of N-balance based model calculations, and also within ground water recharge rates calculated with models commonly used in hydrology. Extrapolation of lysimeter data to a catchment with similar soils provides a reliable basis for estimating the N-leaching caused by a change in agricultural land use. On the basis of the N-loss from the soil and the N-load of the stream, the calculations show that an increase in the proportion of one year rotation fallow from 10 to 25% results in nearly a 10% increase in the N-load of the stream. However, from the point of view of protecting drinking water quality, rotation fallow for one year is not recommended because of the resulting intensified leaching of nitrates.
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Kolupaeva, Victoria N., Ann А. Kokoreva, Alexandra A. Belik, and Pavel A. Pletenev. "Study of the behavior of the new insecticide cyantraniliprole in large lysimeters of the Moscow State University." Open Agriculture 4, no. 1 (October 23, 2019): 599–607. http://dx.doi.org/10.1515/opag-2019-0057.
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AbstractThe behaviour of cyantraniliprole was studied in a lysimetric experiment. The experiment was carried out at the lysimeters of the Soil Research Station of Moscow State University from June 2015 to December 2018. The soil of lysimeter is soddy-podzolic silt loam. The insecticide was applied at the recommended and tenfold rates in 2015 and 2016. The maximum depth of migration of cyantraniliprole in the soil profile was 35 cm in October 2015 and 40 cm in October 2016. Cyantraniliprole was found in the leachate of lysimeter water 2 weeks after its first application in 2015 and continued until the end of 2018, that is, 2 years after the last treatment. Cyantraniliprole was found in most of the water samples analyzed. The maximum concentrations of cyantraniliprole in the leachate were 12.5 and 2.6 μg L−1 in lysimeters with tenfold and recommended doses, with mean values of - 1.7 and 0.6 μg L−1, respectively.
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Salgado, M., M. T. Collins, F. Salazar, J. Kruze, G. Bölske, R. Söderlund, R. Juste, et al. "Fate ofMycobacterium aviumsubsp.paratuberculosisafter Application of Contaminated Dairy Cattle Manure to Agricultural Soils." Applied and Environmental Microbiology 77, no. 6 (January 14, 2011): 2122–29. http://dx.doi.org/10.1128/aem.02103-10.
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ABSTRACTDetails regarding the fate ofMycobacterium aviumsubsp.paratuberculosis(basonym,Mycobacterium paratuberculosis) after manure application on grassland are unknown. To evaluate this, intact soil columns were collected in plastic pipes (lysimeters) and placed under controlled conditions to test the effect of a loamy or sandy soil composition and the amount of rainfall on the fate ofM. paratuberculosisapplied to the soil surface with manure slurry. The experiment was organized as a randomized design with two factors and three replicates.M. paratuberculosis-contaminated manure was spread on the top of the 90-cm soil columns. After weekly simulated rainfall applications, water drainage samples (leachates) were collected from the base of each lysimeter and cultured forM. paratuberculosisusing Bactec MGIT ParaTB medium and supplements. Grass was harvested, quantified, and tested from each lysimeter soil surface. The identity of all probableM. paratuberculosisisolates was confirmed by PCR for IS900and F57 genetic elements. There was a lag time of 2 months after each treatment beforeM. paratuberculosiswas found in leachates. The greatest proportions ofM. paratuberculosis-positive leachates were from sandy-soil lysimeters in the manure-treated group receiving the equivalent of 1,000 mm annual rainfall. Under the higher rainfall regimen (2,000 mm/year),M. paratuberculosiswas detected more often from lysimeters with loamy soil than sandy soil. Among all lysimeters,M. paratuberculosiswas detected more often in grass clippings than in lysimeter leachates. At the end of the trial, lysimeters were disassembled and soil cultured at different depths, and we found thatM. paratuberculosiswas recovered only from the uppermost levels of the soil columns in the treated group. Factors associated withM. paratuberculosispresence in leachates were soil type and soil pH (P< 0.05). ForM. paratuberculosispresence in grass clippings, only manure application showed a significant association (P< 0.05). From these findings we conclude that this pathogen tends to move slowly through soils (faster through sandy soil) and tends to remain on grass and in the upper layers of pasture soil, representing a clear infection hazard for grazing livestock and a potential for the contamination of runoff after heavy rains.
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Dlamini, P., I. B. Ukoh, L. D. van Rensburg, and C. C. du Preez. "Reduction of evaporation from bare soil using plastic and gravel mulches and assessment of gravel mulch for partitioning evapotranspiration under irrigated canola." Soil Research 55, no. 3 (2017): 222. http://dx.doi.org/10.1071/sr16098.
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Partitioning of evapotranspiration (ET) into its components of evaporation (E) and transpiration (T) is difficult, yet important for managing unproductive and productive water losses under irrigated agriculture. A lysimeter experiment (Expt 1) was conducted on sandy Clovelly and sandy loam Bainsvlei soils in Bloemfontein, South Africa where plastic sheet and dolerite gravel mulches were applied to lysimeters to determine to what extent they restricted E from the soil surface compared with a bare soil control. No crops were grown in the lysimeters for Expt 1. Gravel mulch on Clovelly-filled lysimeters reduced E by 33% and by 41% for Bainsvlei-filled lysimeters compared with bare soil. Based on these results, lysimeter Expt 2 was undertaken on gravel mulched and unmulched bare soil lysimeters to assess the effectiveness of gravel mulch in partitioning ET into E and T using the Tanner and Sinclair (1983) method embedded in the soil water balance. In Expt 2, canola (Brassica napus L.) was grown in the lysimeters for 168 days. Gravel mulch had a significant effect on water use (WU) by suppressing the E component of ET, resulting in WU being on average 11% lower from gravel-mulched lysimeters than the unmulched lysimeters, and this translated to an improved average WU efficiency of 11.91kgha–1mm–1 for canola. Taken together, these results reinforce the potential for gravel mulch as a viable management option for soil water conservation, which is crucial for plant available water, a major limiting factor for plant growth in arid and semiarid lands.
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Nicolás-Cuevas, Juan Antonio, Dolores Parras-Burgos, Manuel Soler-Méndez, Antonio Ruiz-Canales, and José Miguel Molina-Martínez. "Removable Weighing Lysimeter for Use in Horticultural Crops." Applied Sciences 10, no. 14 (July 15, 2020): 4865. http://dx.doi.org/10.3390/app10144865.
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Water resources management is a priority issue in agriculture, especially in areas with water supply problems. Recently, one of the most widespread technologies for measuring crop water requirements are weighing lysimeters. Nevertheless, this type of lysimeters are of large dimensions and require a civil work for their installation. In this article, we present a weighing lysimeter prototype (1000 × 600 mm and 350 mm depth) designed to be used in agricultural farming of horticultural crops. We described the design details that includes ease of assembly, carriage and minimum soil alteration. Structural design results and construction process are also provided showing their performance under different tractors scenarios. The measurements accuracy results show the outcomes of the prototype after being tested. Finally, we discuss our design and measurements results by comparing them with other weighing lysimeters. In comparison, the prototype designed is an accurate and reliable device which reduces the surface and depth of the current weighing lysimeters.
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Sagar, Atish, Murtaza Hasan, Dhirendra Kumar Singh, Nadhir Al-Ansari, Debashis Chakraborty, Mam Chand Singh, Mir Asif Iquebal, et al. "Development of Smart Weighing Lysimeter for Measuring Evapotranspiration and Developing Crop Coefficient for Greenhouse Chrysanthemum." Sensors 22, no. 16 (August 19, 2022): 6239. http://dx.doi.org/10.3390/s22166239.
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The management of water resources is a priority problem in agriculture, especially in areas with a limited water supply. The determination of crop water requirements and crop coefficient (Kc) of agricultural crops helps to create an appropriate irrigation schedule for the effective management of irrigation water. A portable smart weighing lysimeter (1000 × 1000 mm and 600 mm depth) was developed at CPCT, IARI, New Delhi for real-time measurement of Crop Coefficient (Kc) and water requirement of chrysanthemum crop and bulk data storage. The paper discusses the assembly, structural and operational design of the portable smart weighting lysimeter. The performance characteristics of the developed lysimeter were evaluated under different load conditions. The Kc values of the chrysanthemum crop obtained from the lysimeter installed inside the greenhouse were Kc ini. 0.43 and 0.38, Kc mid-1.27 and 1.25, and Kc end-0.67 and 0.59 for the years 2019–2020 and 2020–2021, respectively, which apprehensively corroborated with the FAO 56 paper for determination of crop coefficient. The Kc values decreased progressively at the late-season stage because of the maturity and aging of the leaves. The lysimeter’s edge temperature was somewhat higher, whereas the center temperature closely matched the field temperature. The temperature difference between the center and the edge increased as the ambient temperature rose. The developed smart lysimeter system has unique applications due to its real-time measurement, portable attribute, and ability to produce accurate results for determining crop water use and crop coefficient for greenhouse chrysanthemum crops.
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Berisford, Yvette C., Parshall B. Bush, and John W. Taylor. "Leaching and persistence of herbicides for kudzu (Pueraria montana) control on pine regeneration sites." Weed Science 54, no. 02 (April 2006): 391–400. http://dx.doi.org/10.1614/ws-04-094r2.1.
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Clopyralid, picloram, triclopyr, metsulfuron, and tebuthiuron were applied to control kudzu on four loblolly pine forest regeneration sites during July 1997. Spot treatments were applied to recovering kudzu in June 1998 and June 1999. Soil leachate was monitored for these five herbicides from July 1997 to December 2000. All herbicides were detected in shallow (51–58 cm deep) and deep lysimeters (84–109 cm deep). Clopyralid was not persistent and limited leaching occurred, with residue levels of 0.4 to 2.8 μg L−1in 12 of 102 deep lysimeter samples. Picloram was mobile and persisted at 0.6 to 2.5 μg L−1in shallow and deep lysimeters for at least 10 mo after the initial application. Triclopyr residues were not persistent in shallow lysimeters and remained < 6 μg L−1during the study. Metsulfuron persisted at < 0.1 μg L−1for 182 to 353 d in shallow lysimeters and at < 0.07 μg L−1for 182 to 300 d in the deep lysimeters in various plots. Tebuthiuron peaks in the deep lysimeters ranged from 69 to 734 μg L−134 to 77 d after the first spot treatment. In the soil that was essentially a fill area, tebuthiuron residues remained > 400 μg L−1(402–1,660 μg L−1) in the shallow lysimeter samples and > 180 μg L−1(181–734 μg L−1) in the deep lysimeters throughout a 354-d period that followed the first spot application. When used as part of a forest regeneration program, the relative potentials of the herbicides to move into shallow groundwater were: tebuthiuron > picloram > metsulfuron > clopyralid > triclopyr.
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HOWITT, R. W., and S. PAWLUK. "THE GENESIS OF A GRAY LUVISOL WITHIN THE BOREAL FOREST REGION. II. DYNAMIC PEDOLOGY." Canadian Journal of Soil Science 65, no. 1 (February 1, 1985): 9–19. http://dx.doi.org/10.4141/cjss85-002.
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An undisturbed site under forest cover near Breton, Alberta, was chosen to study the dynamics of a Gray Luvisol. Soil moisture and temperature were monitored at selected depths over a 2-yr study period. Canopy drip collectors and gravity lysimeters were used to study soil solution transport and the process of lessivage. The order of cation concentration for canopy drip, LFH and Ae lysimeter samples was K+ > Ca++ > Na+ > Mg++. The lysimeter samples from the Bt showed Na+ > Ca++ > K+ > Mg++. Lysimeter studies further indicated that micaceous clays were being illuviated into the upper Bt horizon. Water movement into the Ae horizon was found to be regulated by the LFH horizon; ice lensing in winter appeared to enhance the formation of the platy structure. The major processes in this soil are the translocation of Fe, Al and organic constituents both in solution and in colloidal form; the concentration of these elements was a function of the rate of water movement. The concentration of other cations was independent of the rate of water movement. Key words: Genesis, pedogenesis, Gray Luvisol, dynamic pedology, clay migration, lessivage, illuviation
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Melo, Talyana K. de, José F. de Medeiros, José E. Sobrinho, Vladimir B. Figueiredo, and Paulo S. de Souza. "Evapotranspiration and crop coefficients of melon plants measured by lysimeter and estimated according to FAO 56 methodology." Engenharia Agrícola 33, no. 5 (October 2013): 929–39. http://dx.doi.org/10.1590/s0100-69162013000500005.
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Aiming at contributing to an adequate management of water resources, this study aimed to analyze and compare evapotranspiration (ETc) and crop coefficients (Kc) of melon plants measured by a lysimeter and estimated according to the FAO 56 methodology, in the city of Mossoró, state of Rio Grande do Norte (RN), Brazil. In order to measure ETc, weighing lysimeters with an area of 2.25m² were used, with two repetitions. The Penman-Monteith equation parameterized by FAO was used to estimate the reference evapotranspiration, and crop coefficients were those recommended in FAO-56 Bulletin adjusted to local climatic conditions. The required climatic data and lysimeter measurements were collected by an automatic weather station installed at the site. The results were compared by means of statistical indicators: of precision (r), of accuracy (d), and performance (c), in daily and weekly intervals. The data estimated by the FAO 56 methodology were adjusted optimally to the values measured by the lysimeters in accordance with index "c" in the two time scales assessed, indicating the potential of the method proposed by FAO to irrigation management in the climatic conditions of Agripole Assú-Mossoró.
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Du, L., C. W. Cuss, M. F. Dyck, T. Noernberg, and W. Shotyk. "Size-resolved analysis of trace elements in the dissolved fraction (<0.45 μm) of soil solutions using a novel lysimeter and asymmetrical flow field-flow fractionation coupled to ultraviolet absorbance and inductively coupled plasma mass spectrometry." Canadian Journal of Soil Science 100, no. 4 (December 1, 2020): 381–92. http://dx.doi.org/10.1139/cjss-2019-0165.
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The distributions of dissolved (<0.45 μm) trace elements (TEs) amongst major colloidal forms in soils have implications for their availability, accessibility, and toxicity to plants and animals. The size-resolved distributions of TE species in soil solutions were collected using lysimeters and were measured using asymmetrical flow field-flow fractionation (AF4) coupled to ultraviolet absorbance (UV) and inductively coupled plasma mass spectrometry (ICP-MS). Using this AF4-UV-ICPMS system, dissolved TEs were separated by size, and concentrations in major forms were quantified: “truly dissolved” primarily ionic and small molecules <ca. 1 kDa, organic-dominated colloids, and primarily inorganic colloids. The soil solutions were collected under vacuum using a novel surgical (316L) stainless steel (SS) lysimeter with a 5 μm pore size. Analyses were performed in the metal-free, ultraclean SWAMP laboratory. The acid-cleaned lysimeters yielded excellent blank values for TEs of environmental interest (i.e., Li, Al, V, Mn, Co, Cu, As, Mo, Ag, Cd, Ba, Pb, Th, and U). Lysimeter sampling offers the major advantage that it can minimize disturbances to the natural TE concentrations and distributions amongst major dissolved colloidal forms in soil solutions and thus provides information that is relevant to plant uptake.
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Zhang, Huihui, Robert Wayne Malone, Liwang Ma, Lajpat R. Ahuja, Saseendran S. Anapalli, Gary W. Marek, Prasanna H. Gowda, Steve R. Evett, and Terry A. Howell. "Modeling Evapotranspiration and Crop Growth of Irrigated and Non-Irrigated Corn in the Texas High Plains Using RZWQM." Transactions of the ASABE 61, no. 5 (2018): 1653–66. http://dx.doi.org/10.13031/trans.12838.
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Abstract. Accurate quantification and management of crop evapotranspiration (ET) are critical to optimizing crop water productivity for both dryland and irrigated agriculture, especially in the semiarid regions of the world. In this study, four weighing lysimeters in Bushland, Texas, were planted to maize in 1994 with two fully irrigated and two non-irrigated for measuring crop ET. The Root Zone Water Quality Model (RZWQM2) was used to evaluate soil water balance and crop production with potential evapotranspiration (PET) estimated from either the Shuttleworth-Wallace method (PTSW) or the ASCE standardized alfalfa reference ET multiplied by crop coefficients (PTASCE). As a result, two water stress factors were defined from actual transpiration (AT) and were tested in the model against the lysimeter data, i.e., AT/PTSW and AT/PTASCE. For both water stress factors, the simulated daily ET values were reasonably close to the measured values, with underestimated ET during mid-growing stage in both non-irrigated lysimeters. Root mean squared deviations (RMSDs) and relative RMSDs (RMSD/observed mean) values for leaf area index, biomass, soil water content, and daily ET were within simulation errors reported earlier in the literature. For example, the RMSDs of simulated daily ET were less than 1.52 mm for all irrigated and non-irrigated lysimeters. Overall, ET was simulated within 3% of the measured data for both fully irrigated lysimeters and undersimulated by less than 11% using both stress factors for the non-irrigated lysimeters. Our results suggest that both methods are promising for simulating crop production and ET under irrigated conditions, but the methods need to be improved for dryland and non-irrigated conditions. Keywords: ET, RZWQM modeling, Stress factor, Weighing lysimeter.
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León, Juan, Vicente Parra, Robinson Peña, Juan Silva, Daniel Román, and Francisco Salazar. "Design, installation and calibration of a block of lysimeters to adjust the crop coefficient." Revista de la Facultad de Agronomía, Universidad del Zulia 39, no. 2 (April 18, 2022): e223926. http://dx.doi.org/10.47280/revfacagron(luz).v39.n2.04.
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The efficient management of water resources using techniques that improve it uses, based on knowledge of evapotranspiration are key elements for crop production. Amongst main techniques for water management, the use of drainage lysimeter installed in the field below vegetable fields may be used to quantify the amount of water needed. The aim of this work is to design, install and calibrate a set of lysimeters for adjusting crop coefficient (Kc). In the calibration of the lysimeters, it was obtained that to induce drainage in lysimeters from one to five, an over-irrigation of 25% of the field capacity was needed, while the rest needed 50%. With lysimeters built the physical characteristic of soil could be simulated in this study.
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Leake, Christopher R. "Lysimeter studies." Pesticide Science 31, no. 3 (1991): 363–73. http://dx.doi.org/10.1002/ps.2780310310.
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Piccinni, Giovanni, Jonghan Ko, Thomas Marek, and Daniel I. Leskovar. "Crop Coefficients Specific to Multiple Phenological Stages for Evapotranspiration-based Irrigation Management of Onion and Spinach." HortScience 44, no. 2 (April 2009): 421–25. http://dx.doi.org/10.21273/hortsci.44.2.421.
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Weighing lysimeters are used to measure crop water use during the growing season. By relating the water use of a specific crop to a well-watered reference crop such as grass, crop coefficients (KC) can be developed to assist in predicting crop needs using meteorological data available from weather stations. This research was conducted to determine growth stage-specific KC and crop water use for onions (Allium cepa L.) and spinach (Spinacia oleracea L.) grown under south Texas conditions. Seven lysimeters, consisting of undisturbed 1.5 × 2.0 × 2.2-m deep soil monoliths, comprise the Texas AgriLife Research–Uvalde lysimeter facility. Six lysimeters, weighing ≈14 Mg, have been placed each in the middle of a 1-ha field beneath a linear low-energy precision application irrigation system. A seventh lysimeter was established to measure reference grass reference evapotranspiration. Daily water use for onion and spinach was measured at 5-min intervals. Crop water requirements, KC determination, and comparison with existing Food and Agricultural Organization (FAO) KC values were determined over a 2-year period for each crop. The KC values determined over the growing seasons varied from 0.2 to 1.3 for onion and 0.2 to 1.5 for spinach with some of the values in agreement with those from FAO. It is assumed that the application of growth stage-specific KC will assist in irrigation management and provide precise water applications for a region of interest.
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Moorhead, Jerry, Gary Marek, Prasanna Gowda, Xiaomao Lin, Paul Colaizzi, Steven Evett, and Seth Kutikoff. "Evaluation of Evapotranspiration from Eddy Covariance Using Large Weighing Lysimeters." Agronomy 9, no. 2 (February 20, 2019): 99. http://dx.doi.org/10.3390/agronomy9020099.
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Evapotranspiration (ET) is an important component in the water budget and used extensively in water resources management such as water planning and irrigation scheduling. In semi-arid regions, irrigation is used to supplement limited and erratic growing season rainfall to meet crop water demand. Although lysimetery is considered the most accurate method for crop water use measurements, high-precision weighing lysimeters are expensive to build and operate. Alternatively, other measurement systems such as eddy covariance (EC) are being used to estimate crop water use. However, due to numerous explicit and implicit assumptions in the EC method, an energy balance closure problem is widely acknowledged. In this study, three EC systems were installed in a field containing a large weighing lysimeter at heights of 2.5, 4.5, and 8.5 m. Sensible heat flux (H) and ET from each EC system were evaluated against the lysimeter. Energy balance closure ranged from 64% to 67% for the three sensor heights. Results showed that all three EC systems underestimated H and consequently overestimated ET; however, the underestimation of H was greater in magnitude than the overestimation of ET. Analysis showed accuracy of ET was greater than energy balance closure with error rates of 20%–30% for half-hourly values. Further analysis of error rates throughout the growing season showed that energy balance closure and ET accuracy were greatest early in the season and larger error was found after plants reached their maximum height. Therefore, large errors associated with increased biomass may indicate unaccounted-for energy stored in the plant canopy as one source of error. Summing the half-hourly data to a daily time-step drastically reduced error in ET to 10%–15%, indicating that EC has potential for use in agricultural water management.
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Matse, Dumsane Themba, Paramsothy Jeyakumar, Peter Bishop, and Christopher W. N. Anderson. "Nitrate Leaching Mitigation Options in Two Dairy Pastoral Soils and Climatic Conditions in New Zealand." Plants 11, no. 18 (September 17, 2022): 2430. http://dx.doi.org/10.3390/plants11182430.
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This lysimeter study investigated the effect of late-autumn application of dicyandiamide (DCD), co-poly acrylic-maleic acid (PA-MA), calcium lignosulphonate (LS), a split-application of calcium lignosulphonate (2LS), and a combination of gibberellic acid (GA) and LS (GA + LS) to reduce N leaching losses during May 2020 to December 2020 in lysimeter field sites in Manawatu (Orthic Pumice soil) and Canterbury (Pallic Orthic Brown soil), New Zealand. In a second application, urine-only, GA only and GA + LS treatments were applied during July 2020 in mid-winter on both sites. Results showed that late-autumn application of DCD, 2LS and GA + LS reduced mineral N leaching by 8%, 16%, and 35% in the Manawatu site and by 34%, 11%, and 35% in the Canterbury site, respectively when compared to urine-only. There was no significant increase in cumulative herbage N uptake and yield between urine-treated lysimeters in both sites. Mid-winter application of GA and GA + LS reduced mineral N leaching by 23% and 20%, respectively in the Manawatu site relative to urine-only treated lysimeters, but no significant reduction was observed in the Canterbury site. Our results demonstrated the potential application of these treatments in different soils under different climate and management conditions.
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Scheiber, S. M., and Richard C. Beeson,. "Landscape Growth and Aesthetic Quality of Coleus Managed with Irrigation Deficits." HortTechnology 17, no. 4 (January 2007): 561–66. http://dx.doi.org/10.21273/horttech.17.4.561.
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Previous research indicated that bedding plants can be maintained in landscape soils allowed to dry to substantially less than field capacity before irrigation; however, canopy size and aesthetic quality were compromised. Continuing this research, ‘Yalaha’ coleus (Solenostemon scutellarioides) were grown in drainage lysimeters in an open-sided clear polyethylene-covered shelter and a companion uncovered field plot to assess growth characteristics and landscape quality when irrigated at various managed allowable deficits. Using tensiometers, plants were irrigated back to field capacity when plant-available water within a soil was depleted to 70% or 50%. Deficits were evaluated against a control treatment of 0.5 inch daily irrigation. Total irrigation volume applied was significantly greater for the control treatments than deficit irrigation treatments. The net result was 78% and 90% average reductions in total volume applied to lysimeter and field-grown coleus respectively. On average, height was 20% and 15% greater for well-watered controls grown in lysimeters and field plots respectively than plants grown in deficit irrigations. Canopy size of nondeficit controls was 26% and 72% greater on average than deficit treatments in lysimeter and field plots respectively. However, shoot and root dry weights, total biomass, shoot-to-root ratios, and landscape quality were similar among treatments for both locations.
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Paulus, Sinikka J., Rene Orth, Sung-Ching Lee, Anke Hildebrandt, Martin Jung, Jacob A. Nelson, Tarek Sebastian El-Madany, et al. "Interpretability of negative latent heat fluxes from eddy covariance measurements in dry conditions." Biogeosciences 21, no. 8 (April 25, 2024): 2051–85. http://dx.doi.org/10.5194/bg-21-2051-2024.
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Abstract. It is known from arid and semi-arid ecosystems that atmospheric water vapor can directly be adsorbed by the soil matrix. Soil water vapor adsorption was typically neglected and only recently received attention because of improvements in measurement techniques. One technique rarely explored for the measurement of soil water vapor adsorption is eddy covariance (EC). Soil water vapor adsorption may be detectable as downwardly directed (i.e., negative) EC latent heat (λE) flux measurements under dry conditions, but a systematic assessment of the use of negative λE fluxes from EC flux stations to characterize adsorption is missing. We propose a classification method to characterize soil water vapor adsorption, excluding conditions of dew and fog when λE derived from EC is not trustworthy due to stable atmospheric conditions. We compare downwardly directed λE fluxes from EC with measurements from weighing lysimeters for 4 years in a Mediterranean savanna ecosystem and 3 years in a temperate agricultural site. Our aim is to assess if overnight water inputs from soil water vapor adsorption differ between ecosystems and how well they are detectable by EC. At the Mediterranean site, the lysimeters measured soil water vapor adsorption each summer, whereas at the temperate site, soil water vapor adsorption was much rarer and was measured predominantly under an extreme drought event in 2018. During 30 % of nights in the 4-year measurement period at the Mediterranean site, the EC technique detected downwardly directed λE fluxes of which 88.8 % were confirmed to be soil water vapor adsorption by at least one lysimeter. At the temperate site, downwardly directed λE fluxes were only recorded during 15 % of the nights, with only 36.8 % of half hours matching simultaneous lysimeter measurement of soil water vapor adsorption. This relationship slightly improved to 61 % under bare-soil conditions and extreme droughts. This underlines that soil water vapor adsorption is likely a much more relevant process in arid ecosystems compared to temperate ones and that the EC method was able to capture this difference. The comparisons of the amounts of soil water vapor adsorption between the two methods revealed a substantial underestimation of the EC compared to the lysimeters. This underestimation was, however, comparable with the underestimation in evaporation by the eddy covariance and improved in conditions of higher turbulence. Based on a random-forest-based feature selection, we found the mismatch between the methods being dominantly related to the site's inherent variability in soil conditions, namely soil water status, and soil (surface) temperature. We further demonstrate that although the water flux is very small with mean values of 0.04 or 0.06 mm per night for EC or lysimeter, respectively, it can be a substantial fraction of the diel soil water balance under dry conditions. Although the two instruments substantially differ with regard to the measured ratio of adsorption to evaporation over 24 h with 64 % and 25 % for the lysimeter and EC methods, they are in either case substantial. Given the usefulness of EC for detecting soil water vapor adsorption as demonstrated here, there is potential for investigating adsorption in more climate regions thanks to the greater abundance of EC measurements compared to lysimeter observations.
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SILVA, GERLANGE SOARES DA, FRANCISCO ADRIANO DE CARVALHO PEREIRA, RODRIGO ALMEIDA SANTANA, THAÍS NASCIMENTO MENESES, OSWALDO PALMA LOPES SOBRINHO, and ALEX SANTANA DO ROSARIO. "CALIBRATION OF A WEIGHING LYSIMETER FOR MEASURING COCOA EVAPOTRANSPIRATION." Revista Caatinga 33, no. 3 (September 2020): 803–14. http://dx.doi.org/10.1590/1983-21252020v33n324rc.
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ABSTRACT Well-operated and calibrated weighing lysimeters reliably determine the water demand of agricultural crops, and the quality of the data is evaluated through the error analyses attributed to the instrument. The objective of this study was to determine performance parameters of a weighing lysimeter and to evaluate its adequacy for the direct determination of cocoa crop evapotranspiration. The lysimeter with 1.44 m2 surface, supported on four load cells installed in the experimental area of the Graduate Program in Agricultural Engineering of the Universidade Federal do Recôncavo da Bahia, was calibrated at 3:00 a.m., using known masses at intervals of 02 minutes in five cycles of addition and removal. Data were collected using a datalogger coupled to four load cells with an individual capacity of 1000 kg, programmed to perform readings every 01 second, storing the averages of 15 minutes. The lysimeter showed excellent accuracy, with r2greater than 0.99 in the correlation between the standard masses and the signal of the load cells and standard error of linear regression estimate of 0.03 mm. The combination of repeatability and hysteresis errors with an uncertainty of 0.19% showed that the load cells have accuracy of ±0.07 mm, with resolution of 0.00033 mV, and sensitivity to detect mass changes below 0.1 mm, the system is adequate for direct measurement of cocoa ETc at time intervals of less than one hour.
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Payero, José O. "An Effective and Affordable Internet of Things (IoT) Scale System to Measure Crop Water Use." AgriEngineering 6, no. 1 (March 13, 2024): 823–40. http://dx.doi.org/10.3390/agriengineering6010047.
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Scales are widely used in many agricultural applications, ranging from weighing crops at harvest to determine crop yields to regularly weighing animals to determine growth rate. In agricultural research applications, there is a long history of measuring crop water use (evapotranspiration [ET]) using a particular type of scale called weighing lysimeters. Typically, weighing lysimeters require very accurate data logging systems that tend to be expensive. Recent developments in open-source technologies, such as micro-controllers and Internet of Things (IoT) platforms, have created opportunities for developing effective and affordable ways to monitor crop water use and transmit the data to the Internet in near real-time. Therefore, this study aimed to create an affordable Internet of Things (IoT) scale system to measure crop ET. A scale system to monitor crop ET was developed using an Arduino-compatible microcontroller with cell phone communication, electronic load cells, an Inter-Integrated Circuit (I2C) multiplexer, and analog-to-digital converters (ADCs). The system was powered by a LiPo battery, charged by a small (6 W) solar panel. The IoT scale system was programmed to collect data from the load cells at regular time intervals and send the data to the ThingSpeak IoT platform. The system performed successfully during indoor and outdoor experiments conducted in 2023 at the Clemson University Edisto Research and Education Center, Blackville, SC. Calibrations relating the measured output of the scale load cells to changes in mass resulted in excellent linear relationships during the indoor (r2 = 1.0) and outdoor experiments (r2 = 0.9994). The results of the outdoor experiments showed that the IoT scale system could accurately measure changes in lysimeter mass during several months (Feb to Jun) without failure in data collection or transmission. The changes in lysimeter mass measured during that period reflected the same trend as concurrent soil moisture data measured at a nearby weather station. The changes in lysimeter mass measured with the IoT scale system during the outdoor experiment were accurate enough to derive daily and hourly crop ET and even detect what appeared to be dew formation during the morning hours. The IoT scale system can be built using open-source, off-the-shelf electronic components which can be purchased online and easily replaced or substituted. The system can also be developed at a fraction of the cost of data logging, communication, and visualization systems typically used for lysimeter and scale applications.
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Shahrajabian, M. H., A. Soleymani, P. O. Ogbaji, and X. Xue. "Impact of Different Irrigation Managements on Soil Water Consumption, Grain Yield, Seed Protein, Phosphorus and Potassium of Winter Wheat." Cercetari Agronomice in Moldova 50, no. 3 (September 1, 2017): 5–13. http://dx.doi.org/10.1515/cerce-2017-0021.
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Abstract To evaluate soil water consumption, changes in quantity and quality of winter wheat seed and forage under different irrigation treatments, an experiment was conducted in Beijing, China, in the 2012-2013. Irrigation treatments were (I1): irrigation before sowing, (I2): irrigation before sowing + before freezing; (I3): irrigation before sowing + before freezing + irrigation in the beginning of erecting stage + irrigation at flowering stage; (I4): irrigation before sowing + irrigation before freezing + irrigation at the booting stage + irrigation at flowering stage. The laid out of experiment was randomized complete block design, repeated six times. The effect of irrigation on total biological yield, grain yield and harvest index is significant. The highest mean soil water consumption in Oct., Nov., Dec., Jan., Feb., Mar., Apr. and May was obtained for lysimeter 10 (I2), lysimeter 10 (I2), lysimeter 6 (I2), lysimeter 10 (I2), lysimeter 10 (I2), lysimeter 10 (I2), lysimeter 11 (I3), and lysimeter 10 (I2), respectively. The results from the study indicate that irrigation winter wheat throughout the booting stage and flowering stage increased grain yield, harvest index, potassium percentage, ash percentage of forage wheat at flowering stage, seed and forage protein percentage. Evapotranspiration trends increased steadily, especially in last three months, in which the lysimeter fields were covered by winter wheat completely.
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Schnepper, Tobias, Jannis Groh, Horst H. Gerke, Barbara Reichert, and Thomas Pütz. "Evaluation of precipitation measurement methods using data from a precision lysimeter network." Hydrology and Earth System Sciences 27, no. 17 (September 11, 2023): 3265–92. http://dx.doi.org/10.5194/hess-27-3265-2023.
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Abstract. Accurate precipitation data are essential for assessing the water balance of ecosystems. Methods for point precipitation determination are influenced by wind, precipitation type and intensity and/or technical issues. High-precision weighable lysimeters provide precipitation measurements at ground level that are less affected by wind disturbances and are assumed to be relatively close to actual precipitation. The problem in previous studies was that the biases in precipitation data introduced by different precipitation measurement methods were not comprehensively compared with and quantified on the basis of those obtained by lysimeters in different regions in Germany. The aim was to quantify measurement errors in standard precipitation gauges as compared to the lysimeter reference and to analyze the effect of precipitation correction algorithms on the gauge data quality. Both correction methods rely on empirical constants to account for known external influences on the measurements, following a generic and a site-specific approach. Reference precipitation data were obtained from high-precision weighable lysimeters of the TERrestrial ENvironmental Observatories (TERENO)-SOILCan lysimeter network. Gauge types included tipping bucket gauges (TBs), weighable gauges (WGs), acoustic sensors (ASs) and optical laser disdrometers (LDs). From 2015-2018, data were collected at three locations in Germany, and 1 h aggregated values for precipitation above a threshold of 0.1 mm h−1 were compared. The results show that all investigated measurement methods underestimated the precipitation amounts relative to the lysimeter references for long-term precipitation totals with catch ratios (CRs) of between 33 %–92 %. Data from ASs had overall biases of −0.25 to −0.07 mm h−1, while data from WGs and LDs showed the lowest measurement bias (−0.14 to −0.06 mm h−1 and −0.01 to −0.02 mm h−1). Two TBs showed systematic deviations with biases of −0.69 to −0.61 mm h−1, while other TBs were in the previously reported range with biases of −0.2 mm h−1. The site-specific and generic correction schemes reduced the hourly measurement bias by 0.13 and 0.08 mm h−1 for the TBs and by 0.09 and 0.07 mm h−1 for the WGs and increased long-term CRs by 14 % and 9 % and by 10 % and 11 %, respectively. It could be shown that the lysimeter reference operated with minor uncertainties in long-term measurements under different site and weather conditions. The results indicate that considerable precipitation measurement errors can occur even at well-maintained and professionally operated stations equipped with standard precipitation gauges. This generally leads to an underestimation of the actual precipitation amounts. The results suggest that the application of relatively simple correction schemes, manual or automated data quality checks, instrument calibrations, and/or an adequate choice of observation period can help improve the data quality of gauge-based measurements for water balance calculations, ecosystem modeling, water management, assessment of agricultural irrigation needs, or radar-based precipitation analyses.
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Wegehenkel, Martin, and Horst H. Gerke. "Comparison of real evapotranspiration measured by weighing lysimeters with simulations based on the Penman formula and a crop growth model." Journal of Hydrology and Hydromechanics 61, no. 2 (June 1, 2013): 161–72. http://dx.doi.org/10.2478/johh-2013-0021.
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Abstract Although the quantification of real evapotranspiration (ETr) is a prerequisite for an appropriate estimation of the water balance, precision and uncertainty of such a quantification are often unknown. In our study, we tested a combined growth and soil water balance model for analysing the temporal dynamics of ETr. Simulated ETr, soil water storage and drainage rates were compared with those measured by 8 grass-covered weighable lysimeters for a 3-year period (January 1, 1996 to December 31, 1998). For the simulations, a soil water balance model based on the Darcy-equation and a physiological-based growth model for grass cover for the calculation of root water uptake were used. Four lysimeters represented undisturbed sandy soil monoliths and the other four were undisturbed silty-clay soil monoliths. The simulated ETr-rates underestimated the higher ETr-rates observed in the summer periods. For some periods in early and late summer, the results were indicative for oasis effects with lysimeter-measured ETr-rates higher than corresponding calculated rates of potential grass reference evapotranspiration. Despite discrepancies between simulated and observed lysimeter drainage, the simulation quality for ETr and soil water storage was sufficient in terms of the Nash-Sutcliffe index, the modelling efficiency index, and the root mean squared error. The use of a physiological-based growth model improved the ETr estimations significantly.
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Baalousha, Husam Musa, Fanilo Ramasomanana, Marwan Fahs, and Thomas Daniel Seers. "Measuring and Validating the Actual Evaporation and Soil Moisture Dynamic in Arid Regions under Unirrigated Land Using Smart Field Lysimeters and Numerical Modeling." Water 14, no. 18 (September 8, 2022): 2787. http://dx.doi.org/10.3390/w14182787.
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Though forming a fundamental component of the water budget, soil evaporation is challenging to quantify in practice. Most water balance and soil moisture studies rely on pan evaporation or empirical relations to calculate evaporation, which is later used for water budget estimation. This study is based on the in situ measurement of soil evaporation in arid regions using smart field lysimeters. These lysimeters calculate the actual evaporation and downward leakage within the soil column using changes in weight, in addition to measuring temperature, soil moisture, soil matric potential, and other ancillary parameters in real time. The study analyses 17 months of data collected from two smart-field lysimeters installed in loamy soil within unirrigated land in Qatar. Lysimeter data were validated using a 1D numerical unsaturated flow model using Hydrus, and utilized laboratory testing results of the water retention. The Hydrus model output shows a good match between numerical and lysimeter results. The volumetric soil moisture of the topsoil in the lysimeters varies between 6% and 36%, with a rapid response to rainfall events. The actual recharge based on data analysis amounts to 5% of the annual rainfall. An analysis of the results reveals a substantial difference between the potential evaporation and the actual evaporation. While the potential values can be adequate for wet countries where rainfall is high, it is irrelevant in arid countries, due to the lack of moisture available for evaporation throughout most of the year. Results also show that while the topsoil responds quickly to rainfall events, it takes a considerable amount of time until such effects are propagated to below the soil’s lower boundary. The findings of this study may help decision makers, researchers, and irrigation engineers plan for the sustainable management and protection of scarce resources.
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David, Mark B., and George Z. Gertner. "Sources of variation in soil solution collected by tension plate lysimeters." Canadian Journal of Forest Research 17, no. 2 (February 1, 1987): 191–93. http://dx.doi.org/10.1139/x87-033.
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Soil solutions were collected at hardwood and conifer sites located on Typic Haplorthods using tension plate lysimeters and examined for random variation effects due to differences in pits, individual lysimeters, and period of collection. Analysis of variance using a partially nested design indicated that for solution volume, H+, specific conductance, and base cations, a large part of the random variation (>55%) in solution characteristics was due to differences within sampling periods. Differences between pits or lysimeters were generally significant for total S and [Formula: see text] only. These data indicate that the lysimeter sampling design used in this study (two lysimeters per horizon, two pits per site) was adequate in collecting representative solution concentrations for the fraction of soil water collected. For total S and [Formula: see text] concentrations, measurements could be improved by increasing the number of pits and lysimeters per pit for sample collection, whereas for other characteristics increased sampling frequency (greater than weekly) would be needed to reduce random variation.
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Storlie, Craig A., and Paul Eck. "Lysimeter-based Crop Coefficients for Young Highbush Blueberries." HortScience 31, no. 5 (September 1996): 819–22. http://dx.doi.org/10.21273/hortsci.31.5.819.
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Inexpensive weighing lysimeters ($1475/unit) were constructed for measuring evapotranspiration of young highbush blueberries (Vaccinium corymbosum L.). The use of a single load cell and other design characteristics decreased lysimeter measurement accuracy but minimized lysimeter construction costs. Measurement error was within ±3%. Crop coefficient (CC) curves for 5- and 6-year-old `Bluecrop' highbush blueberry plants in their third and fourth year of production were generated using reference evapotranspiration and crop water use data from the 1991 and 1992 growing seasons. The CC increased during leaf expansion and flowering in the spring to its maximum value of about 0.19 in 1991 and 0.27 in 1992 and remained near these values until leaves began senescing in the fall. Water use on sunny days during June, July, and August ranged from (liters/bush each day) 3.5 to 4.0 in 1991 and 4.0 to 4.5 in 1992. During the second year of the study, plants had an average height of 0.9 m, an average diameter of 0.9 m, and covered 18% of the total cultivated area. The maximum calculated CC was equal to 1.5 times the measured canopy cover percentage.