Wetted Soil Volume Research Articles

Measuring and modeling two-dimensional irrigation infiltration under film-mulched furrows

Furrow irrigation with film-mulched agricultural beds is being promoted in the arid region of northwest China because it im-proves water utilization. Two-dimensional infiltration patterns under film-mulched furrows can provide guidelines and criteria for irrigation design and operation. Our objective was to investigate soil water dynamics during ponding irrigation infiltration of mulched furrows in a cross-sectional ridge-furrow configuration, using laboratory experiments and mathematical simulations. Six experimental treatments, with two soil types (silt loam and sandy loam), were investigated to monitor the wetting patterns and soil water distribution in a cuboid soil chamber. Irrigation of mulched furrows clearly increased water lateral infiltration on ridge shoulders and ridges, due to enhancement of capillary driving force. Increases to both initial soil water content (SWC) and irrigation water level resulted in increased wetted soil volume. Empirical regression equations accurately estimated the wetted lateral distance ( R l ) and downward distance ( R d ) with elapsed time in a variably wetted soil medium. Optimization of model parameters followed by the Inverse approach resulted in satisfactory agreement between observed and predicted cumulative infiltration and SWC. On the basis of model calibration, HYDRUS-2D model can accurately simulate two-dimensional soil water dynamics under irrigation of mulched furrows. There were significant differences in wetting patterns between unmulched and mulched furrow irrigation using HYDRUS-2D simulation. The R d under the mulched furrows was 32.14% less than the unmulched furrows. Therefore, film-mulched furrows are recommended in a furrow irrigation system.

English

The use of different water depths and soil surface soil surface wetted areas by micro-sprinkler irrigation systems results different wetted soil volumes and evapotranspiration conditions, which may cause changes in fruit production quality and quantity. The objective of this study was to evaluate yield, fruit physical characteristics and leaf area of ​​banana cv. Grand Naine under different irrigation depths and soil surface wetted areas in Northern Minas Gerais State, Brazil. The experiment was conducted in the period 2003 to 2006, involving three production cycles of 'Grand Naine' banana with planting spacing of 3.0 m × 2.7 m irrigated by micro-sprinklers. The experimental design was a randomized block with four replicates in a split-plot arrangement with three soil surface wetted areas in the plot and five irrigation depths as subplots. The irrigation levels were taken as fractions of crop evapotranspiration (ETc): 0.70; 0.85; 1.00; 1.15 and 1.30 ETc, and the soil surface wetted areas (Wa) were: Wa 1 of 10.17 m2, with emitter of 20 L h-1 and radius of throw of 1.8 m; Wa 2 of 23.74 m2, with emitter of 63.6 L h-1 and radius of throw of 2.7 m and Wa 3 of 28.26 m2, with emitter of 60 L h-1 and radius of throw of 3.0 m. Central fruit diameter and mean weight, leaf area and yield of 'Grand Naine' banana were not influenced by irrigation depths. On the other hand, smaller soil surface wetted area causes reduction in central fruit length and weight, leaf area and yield of 'Grand Naine' banana. Key words: Musa spp., irrigation management, soil surface wetted area.

Pattern of soil physical properties in intensive plum and apple orchards on medium and coarse textured soils

The purpose of this paper is to test uniformity of some soil physical properties in loamy-textured and coarse-textured soils within intensive orchards and to find out the specific pattern, in order to use it in general orchard management. Undisturbed soil samples were taken from both in-row (IR) and inter-row (ITR) positions within a transect section between two adjacent tree rows. Within this transect there were nine vertical sampling sections spaced 0.5m apart. Soil bulk density, macro-porosity, saturated hydraulic conductivity and penetration resistance were determined. The pattern of soil physical properties in loamy-sandy and sandy-loamy textured soils is different in intensive orchards from that of arable soils with homogeneous tillage, showing thus the dynamics of soil state. The soil physical properties studied were found to be less favorable to plants in ITR than in IR due to the technological traffic in such environments, after only six years since the orchards were established. The former deep plowing and deep loosening seem to still have favorable consequences for the 0.5m topsoil physical state in orchards. This shows the beneficial effects of these works that should be recommended whenever such plantations are established on such compacted soils. Cutting tree roots can also be done at a distance of 0.5–0.7m away from tree rows if an increased control on the irrigation regime and wetted soil volume is required for drip irrigation.

Potato performance as influenced by the proportion of wetted soil volume and nitrogen under drip irrigation with plastic mulch

Scarce water resources and substantial food demands require efficient water use in arid Northwestern China. Field experiments were conducted to investigate the effects of the proportion of wetted soil (P) and nitrogen fertilizer (N) on potato yield, crop evapotranspiration (ETc), water use efficiency (WUE), and quality under drip irrigation with plastic mulch. In 2012, a factorial trial was conducted with two soil wetting proportions (40% and 70%) and five N rates (90, 135, 180, 225 and 270kgNha−1). In 2013, a factorial trial tested two soil wetting proportions (50% and 75%) and four N rates (90, 150, 210 and 270kgNha−1). Results showed that seasonal ETc was greater with higher P, but the difference in ETc was not significant among different N rates. Although tuber yields of different P levels were not statistically different, yields with lower P were numerically larger than with higher P. The water was used more efficiently with lower proportions of wetted soil. Potato yield, WUE, and tuber starch and vitamin C content responded quadratically to the rate of applied N. Tuber protein was positively and linearly correlated with the N rate. The results suggest that potato could be cultivated with a moderate P (40–50%) and an intermediate rate of applied N (135–150kgNha−1) under drip irrigation with mulch, achieving acceptable yields and quality while saving irrigation water and conserving N fertilizer.

An analytical approach to predict the moistened bulb volume beneath a surface point source

An analytical approach for predicting the wetted soil volume underneath an emitter laid on the ground surface is developed. The approach is based on: (1) the Green and Ampt assumption, (2) Hammami et al. model that enables the inference of the wetted soil depth from the radius of the humid area at the ground surface and (3) the hypothesis that the bulb keeps a semi-elliptical shape whose diagonals are merged with the soil surface and the symmetry axis, respectively. Knowing the initial water content θi, the soil hydraulic conductivity Kf and the water content θf at wetting front position, the proposed approach allows the inference of the wetted bulb volume from the radius of the wetted spot at the soil surface. Experimental trials were carried out in laboratory conditions to assess the relevance of the proposed method. The measurements were made during the infiltration process in three soil types: loamy clay, sandy clay loam and sandy clay. The wetting front progression was monitored via the measurement of the wetting front radius Rf(t) at the soil surface and the determination of the moistened bulb volume Vb(t) by water balance equation. The Vb(t) values thus determined were compared to those predicted by the present approach. The results exhibit a good agreement between calculated and predicted data. Furthermore, predicted values are close to those inferred from Healy and Warrick (1988) model.

Experimental and Numerical Analysis of Drip Tape Layout for Irrigation of Sugarcane in Latosol

A laboratory soil column experiment was first conducted to analyze water movement in latosol of sugarcane field under drip irrigation from single-point source at different emitter discharge rates. Next, a mathematical model of soil water movement under drip irrigation from single-point source was built using Hydrus-3D, which could accurately simulate the shape of the wetted soil volume and the distribution of volumetric water content in the experiment. Further, a Hydrus- 3D model of soil water movement under drip irrigation from double-point source was built and then used to analyze the effects of critical parameters on irrigation uniformity. Results showed that emitter spacing affected irrigation uniformity greatly, but emitter discharge rate did not. According to the irrigation uniformity, project cost and operational management patterns, appropriate drip tape parameters for irrigation of sugarcane in latosol were determined: emitter discharge rate 1.38 L/h, emitter spacing 30 cm, and single-emitter irrigation volume 9.0 L.

A MODIFIED EMPIRICAL MODEL FOR ESTIMATING THE WETTED ZONE DIMENSIONS UNDER DRIP IRRIGATION

Drip irrigation system has become one of the most common irrigation systems especially in arid and semi-arid regions due to its advantages in saving water. One of the most essential considerations in designing these systems is the dimensions of the wetted soil volume under emitters. These dimensions are significant in choosing the proper emitter spacing along the laterals and the suitable distance between laterals. In this study, a modified empirical equations for estimating the horizontal and vertical extend of the wetted zone under surface emitters were suggested. Data from published papers includes different conditions of soil properties and emitter discharge were used in deriving the empirical model using the nonlinear regression. The developed model has high value for coefficient of determination, R2. The results from the developed model were compared with results of other empirical models derived by other researchers. Some statistical criteria were used to evaluate the model performance which are the mean error ME, root mean square error RMSE, and model efficiency EF. The results revealed that the modified model showed good performance in predicting the wetted zone dimensions and it can be used in design and management of drip irrigation systems.

Soil Wetting Patterns and Water Distribution as Affected by Irrigation for Uncropped Ridges and Furrows

The ridge-furrow tillage combined with furrow irrigation is being more widely applied and has been shown to be effective in the Loess Plateau of China. Accurate characterization of water infiltration behavior under ridge-furrow irrigation could provide guidelines and criteria for future irrigation system design and operation. Our objective was to investigate soil water behavior during ponding infiltration in a cross-sectional ridge-furrow configuration. Soil water movement within three different soil textures was tested by tracking the spatial and temporal soil water content (SWC) variations in a soil chamber. The two-dimensional transient flow initially transferred rapidly, but gradually decreased with elapsed infiltration time, approaching a stable flow after 90 min. A technical parameter equation incorporating the Philip equation was developed using the water balance method to accurately predict total applied water volume (TAWV). The wetting patterns moved outward in an elliptical shape. The wetted lateral and downward distances fitted using equations accounted for capillary and gravitational driving forces in variably wetted soil media. Increasing initial SWC resulted in an increase in wetted soil volume, which can also be caused by decreasing bulk density in a homogeneous soil. Higher water level produced greater wetted lateral distance and more irrigation uniformity. The wetted lateral distance was almost identical to the wetted depth in silty clay loam soil; hence ridge-furrow irrigation should be implemented in such finer-textured soils. The wetted soil volume differed markedly among different soil textures (hydraulic properties), demonstrating that these properties can largely determine soil water spreading patterns and distribution.

Salt water dynamics under point source of drip irrigation-A Review

The shrinking fresh water resources have motivated many researchers to investigate and evaluate the use of poor quality saline water using improved irrigation techniques such as drip irrigation. Saline water application through a point drip source in the root zone adversely impact the crop due to accumulated salts. The shape of wetted soil volume has remained of great interest since the advent of drip irrigation. The accumulation of the salts is mostly found towards the outer wetted zone, the knowledge of the actual shape and size in case of a point source of drip irrigation has remained a matter of concern to researchers for the purpose of design and operation of this irrigation system could be further refined. An attempt has been made in this paper to review the works conducted and reported worldwide and specially in India to monitor and evaluate the wetting front and salt movement within it under a point source of drip irrigation. This review can guide a definite methodology to evaluate salt accumulation and its impact on crop growth as well as its mathematical modelling.

Estimation of water consumption as affected by measurement locations of soil water content in drip irrigated tomato in solar greenhouses

土壤水分传感器埋设位置的选择是局部灌溉条件下获得作物根区代表性土壤含水率数据, 从而制定滴灌灌溉制度的关键。本文以日光温室滴灌番茄为对象, 研究滴灌线源土壤湿润体内含水率分布状况, 通过对比距滴灌带不同位置处土壤含水率监测结果估算番茄耗水量的差异, 探讨土壤含水率监测的合理位置。结果表明, 番茄生育期内14~25 mm的灌水定额主要用于增加0~40 cm土层的土壤含水率, 湿润体内日平均土壤含水率分布在75%~100%田间持水率。作物生育期内连续多次滴灌条件下, 沿滴灌带单个灌水器形成的湿润土体会充分叠加, 形成近似均匀的土壤含水率带状分布, 且作物生育期内沿深度方向0~40 cm土层土壤含水率均值无显著性差异, 距滴灌带不同水平距离的土壤含水率随时间的变化趋势具有同步特点, 无明显的滞后性。以集中80%总根量的土壤深度作为滴灌番茄水分渗漏下界面时, 14~25 mm的灌水定额会导致深层渗漏, 且深层渗漏量表现出一定的空间变异性。番茄生育期内深层渗漏量约占灌水量的13%。距滴灌带不同位置处的番茄耗水量除在番茄苗期和开花座果期有较大差异外, 其余生育阶段的差异均在10%以内。对温室滴灌番茄来说, 滴灌高频少量的灌溉特征有利于维持作物根系层适宜的土壤水分状态, 监测1个含水率剖面即可满足估算作物耗水量的要求。

Soil moisture regimes under point irrigation

The main objective of this paper is determination of principal relationships influencing the distribution of moisture content in a soil profile under an emitter in point irrigation. Research was carried out by conducting field experiments. They determined geometry of wetted soil volume in a soil profile under point irrigation. Infiltration of water from a single emitter and the resulting spatial distribution is a typical feature of localized irrigation technology. The field experiments using different emitter discharges and various periods of irrigation on haplic Luvisol (ha LV) (ALFISOLS Udalfs) on loess were conducted in a soil profile 1m deep.Admissible duration of irrigation in relation to discharge rates has been calculated and illustrated in a graph. Incorrect irrigation practices can cause serious environmental damage. A method for determining the width and depth of the wetted soil volume under the point irrigation was developed. This method is rapid and simple, and it gives consistent results.

Effect of pulse drip irrigation and mulching systems on yield, quality traits and irrigation water use efficiency of soybean under sandy soil conditions

Two field experiments were carried out during growing seasons 2010 and 2011, it executed in research farm of national research center in Nubaryia region, Egypt to study the effect of pulse drip irrigation and mulching systems for saving water, increasing and improving yield of soybean. The study factors were, pulse drip irrigation technology (adding of daily water requirements on 4 times, 8 times, 12 times compared with adding of daily water requirements on 1 time) and mulching systems (covering the soil with black plastic mulch “BPM”, rice straw mulch “RSM” and the control treatment was soil surface without mulch “WM”). The following parameters were studied to evaluate the effect of pulse drip irrigation and mulching systems: 1) Soil moisture distribution in root zone, 2) Growth characters of soybean plant, 3) Yield of soybean, 4) Irrigation water use efficiency of soybean “IWUE soybean”, and 5) Oil content and oil yield, 6) Protein content and protein yield, 7) Economical parameter. According to the economical view and the results of statistical analysis for effect of pulse drip irrigation and mulching systems on yield, quality traits and IWUE soybean indicated that, applying the irrigation requirements on 8 pulses/day with using BPM is the best conditions because under these conditions was occurred the highest value of yield, quality traits and IWUE soybean and there was significant deference between this case and other treatments. Where, pulse irrigation technique increase from water movement in horizontal direction than vertical direction hence improve from soil moisture distribution and wetted soil volume in root zone and using BPM decrease from evaporation process rate from soil surface hence decreasing of salts accumulation in addition to decreasing of weed growth in the root zone. All traits at AIR on 12 pulses/ day are decreased by increasing of pulses, this may be due to irrigation water was very small with every pulse at AIR on 12 pulses/day in addition increasing the total time of time-off, this mean, un-sufficient application for irrigation water to remove water stress in the root zone.

Numerical evaluation of subsurface trickle irrigation with brackish water

In this study, an assessment for a proposed irrigation system in the El-Salam Canal cultivated land, Egypt, was conducted. A numerical model (HYDRUS-2D/3D) was applied to investigate the effect of irrigation amount, frequency, and emitter depth on the wetted soil volume, soil salinity levels, and deep percolation under subsurface trickle irrigation (SDI) of tomato growing with brackish irrigation water in three different soil types. The simulations indicated that lower irrigation frequency increased the wetted soil volume without significant increase in water percolates below the plant roots. Deep percolation decreased as the amount of irrigation water and emitter depth decreased. With the same amount of irrigation water, the volume of leached soil was larger at lower irrigation frequency. The salinity of irrigation water under SDI with shallow emitter depth did not show any significant effect on increasing the soil salinity above tomato crop salt tolerance. Based on the results, it appears that the use of SDI with brackish irrigation water is an effective method for growing tomato crop in El-Salam Canal cultivated land especially with shallow emitter depth.

Estimativa de dimensões de volume de solo molhado na irrigação por gotejamento superficial em solo de textura média: condição inicial de solo seco

The use of models to describe or estimate the water distribution in the wetted soil volume can be an important alternative in the definition of the irrigation management and design. The objective of this work was to estimate dimension data of soil wetted volume generated in different soil types under surface drip irrigation using mathematical models of the literature. There were selected data from one class of soil (loam soil), simulating three emitter flow rates (0.503, 1.48 and 2.70 L h-1) and 12 soil water application times (1 to 12 h) with a dry initial soil condition. The values of the wetting pattern were estimated (maximum width and maximum depth) by the five studied models (one numerical, one analytical and three empirical). The simulated maximum width ranged from 18.67 to 108.89 cm and maximum depth ranged from 5.98 to 61.75 cm. The numerical (PSIGS) and analytical (WetUp) models present more reliable results. The empirical model DIPAC presents results with values and behavior similar to those of more robust models.

Stemflow variation in Mexico’s northeastern forest communities: Its contribution to soil moisture content and aquifer recharge

► A comprehensive stemflow dataset was collected for two Mexico’s northern plant communities. ► For each species and for each stand, stemflow coefficients and infiltration depths are reported. ► Statistical stemflow differences are found between the species, plant communities and stands. ► Stemflow extrapolated threefold from trees to stands because of overstocked forests. ► Temperate forest stemflow appears to contribute to aquifer recharge because of shallow soils. Stemflow hydro-ecological importance was measured in trees and assessed in Mexico’s northeast forest stands by answering three basic questions: (a) what are the intra and inter-specific stemflow variations; (b) is the stemflow coefficient constant from tree level to stand scales? and (c) what is the stemflow area and wetted soil volume in individual trees and the stemflow volume discharged at the stand scale in two plant communities of northeastern Mexico? Gross rainfall and stemflow flux measurements were conducted on 78 trees of semi-arid, sub-tropical (31 Diospyros texana ; 14 Acacia rigidula ; four Bumelia celastrina ; five Condalia hookeri ; three Cordia bioissieri ; three Pithecellobium pallens ) and temperate forest communities (six Pinus pseudostrobus Lindl. and 12 Quercus spp.). Stemflow was extrapolated from individual trees to the stand scale using 98 inventory plots (1600 m 2 ha −1 each) placed in oak–pine forests and 37 quadrats (5 m × 5 m each) distributed across the Tamaulipan thornscrub forest range. Stemflow infiltration flux and infiltration area measurements assessed the wetted soil volume. Daily measurements were conducted from May of 1997 to November of 1998. Results showed that stemflow coefficients varied between plant communities since they averaged (confidence intervals, α = 0.05) 2.49% (0.57), 0.30% (0.09), and 0.77% (0.27) of the bulk precipitation for Tamaulipan thornscrub, pine, and oak forests, respectively. Intra-specific stemflow variations could not be identified in Tamaulipan although in temperate tree species. Basal diameter explained intra-specific stemflow variation in both plant communities. Stemflow increased threefold since it accounted for by 6.38% and 2.19% of the total bulk rainfall for Tamaulipan thornscrub quadrats and temperate oak–pine inventory plots, respectively. Small shrubs growing underneath large trees, in combination with the presence of small-diameter trees that recorded the largest stemflow coefficients appear to explain the increase of the stemflow coefficient from trees to stands. Stemflow replenishes soil moisture on the average 4.5 (1.4) times larger than does incident rainfall in open soils and appear to contribute to aquifer recharge in temperate forests due to a combination of shallow soils, high infiltration fluxes and the stemflow volume generated during rainfalls with depths >15 mm. Tracing studies should be conducted to test the hypothesis of the stemflow contribution to aquifer recharge in temperate forests of northeastern Mexico.

A partial root zone drying irrigation strategy for citrus—Effects on water use efficiency and fruit characteristics

Abstract In Australian irrigated citriculture, fruit yield and quality outcomes are not tightly related to levels of plant available water, which raises the possibility of using mild water stress applied to part of the root zone, i.e. partial root zone drying, to stimulate physiological mechanisms that reduce tree water use by changing the relationship between stomatal conductance and ambient evaporative conditions. The PRD technique alternates irrigation such that one side of the tree root zone is allowed to dry whilst the other side is irrigated. This significantly reduces the wetted soil volume at any point in time, whilst always maintaining a readily available water supply to part of the root zone. By adopting this irrigation strategy water use of mature Navel orange trees C. sinensis (L.) Osbeck was reduced and water use efficiency was increased. The technique did not induce excessive fruitlet drop and crop yield was unaffected. Both fruit size and juice percentage slightly decreased whereas total soluble solids percentage (TSS) and juice acid percentage increased. As water use was reduced and juice quality attributes were increased, this technique has obvious benefits for juice fruit production. PRD offers an advantage over conventional deficit irrigation strategies because it helps reduce water use by separating the biochemical signaling responses to water deficit in the dry part of the root zone from the physical effects of reduced stomatal conductance due to lower water availability, allowing developmental processes associated with plant growth to remain unperturbed. Irrigating a reduced root zone volume in this way reduces crop water requirement. However, it is also important to understand that this technique pushes the crop to its limits and should only be applied to well established healthy trees. When applying PRD irrigation, it is important that water is supplied with sufficient frequency and depth of wetting to meet the water needs of the whole plant.

Aplicação de modelos matemáticos na estimativa do volume de bulbo molhado por gotejamento superficial em diferentes tipos de solo

A informação do volume de solo molhado pela irrigação localizada é importante para o dimensionamento e manejo da irrigação por gotejamento superficial, bem como para a estimativa da quantidade de água disponível para as plantas. Com o objetivo de avaliar cinco modelos para estimar o volume molhado pela irrigação por gotejamento superficial, foram instalados experimentos em seis tipos de solos (Luvissolo Crômico, Argissolo Vermelho-Amarelo, Cambissolo Háplico, Neossolo Quartzarênico, Latossolo Vermelho e Neossolo Flúvico). A partir desses experimentos, constatou-se que, com exceção do modelo proposto por NARDA & CHAWLA, os demais modelos estimam satisfatoriamente o volume de solo molhado pela irrigação por gotejamento superficial. Além disso, concluiu-se que o volume médio molhado para as mesmas combinações entre a vazão do emissor e o tempo de aplicação de água foram maiores para o Argissolo e menores para o Neossolo Flúvico e que, com exceção do Argissolo e do Neossolo Flúvico, o volume molhado do solo pode ser estimado por uma única equação em função do volume de água aplicado e do tempo de aplicação de água.

Respuesta del duraznero a diferentes patrones de aplicación del agua

Se realizó un experimento durante tres años (2004/05 a 2006/07) sobre un monte de duraznero recién implantado en el sur de Uruguay. Se aplicaron cinco tratamientos de riego: secano (T1), goteros de 1,6 L h-1 a 0,4 m (T2), goteros de 4 L h-1 a 1 m (T3), microjets de 21 L h-1 a 5 m (T4) y goteros de 2 L h-1 a 1 m, dos líneas por fila (T5), en un diseño experimental en cuadro latino. Las parcelas eran de siete plantas en un marco de plantación de 2,5 x 4,5 m. En todos los tratamientos con riego se aplicó la misma dosis de agua, de forma de cubrir el 100% de la ETc. El porcentaje de volumen de suelo mojado fue de 16, 18, 22 y 44% para los tratamientos T2, T3, T4 y T5 respectivamente. En las variables peso de poda, potencial hídrico foliar y xilemático, conductancia estomática, crecimiento de frutos, rendimiento y tamaño promedio de los frutos, los tratamientos que recibieron riego no se diferenciaron estadísticamente entre sí, pero todos presentaron valores significativamente superiores al secano (p < 0,05). No se evidenció ninguna respuesta entre los tratamientos regados al porcentaje de suelo mojado, para todas las variables analizadas. Se plantea la hipótesis que los efectos de estos tratamientos, en un cultivo perenne, serían acumulativos y se podrían expresar en años sucesivos.

Wet bulb dimensions in surface drip irrigation

Information on the geometry of wetted soil volume under trickle irrigation is important for design and operation of this irrigation system, and also for the management of the irrigation. For this, six experiments were installed in different soils with the objective of evaluate the dimensions of the wetted bulb as function of emitter discharged and water application time, using the power model. It was concluded that the wetted bulb dimensions can be predicted satisfactorily using the power model for all the soils tested.

Distribuição de água no solo aplicado por gotejamento enterrado e superficial

Devido à falta de estudos sobre o movimento da água quando aplicada abaixo da superfície, realizou-se este trabalho com o objetivo de avaliar a distribuição de água aplicada pelo sistema de gotejamento enterrado e convencional. O experimento de campo foi conduzido na área experimental do Departamento de Engenharia Rural da ESALQ/USP - Piracicaba, SP. Para o estudo, trincheiras foram abertas e instaladas sondas de TDR, dispostas a 0,05; 0,15; 0,25; 0,35 e 0,45 m profundidade, e a 0,05; 0,15; 0,25; 0,35 m comprimento, totalizando 17 sondas por trincheira. Os tratamentos foram baseados na profundidade de aplicação (0,0 e 0,10 m) e vazão aplicada (2 e 4 L h-1): ENT2; ENT4; SUP2 e SUP4. A cada hora era aplicado 1 L de água (total de 10 L), seguida de leituras com o TDR. Medições do disco úmido e saturado foram feitas com régua milimetrada; além disso, estabeleceu-se um volume controle onde foi avaliada a uniformidade de aplicação; assim, foi possível verificar, em relação aos sistemas superficiais, que os sistemas enterrados apresentaram menor área superficial molhada e atingiram maior largura e profundidade; já as maiores concentrações foram obtidas próximas ao ponto de emissão.