Study of the wet bulb in drip irrigation in stratified soils using HYDRUS

2020 ◽  
Author(s):  
José Roldán Cañas ◽  
Antonio Jesús Zapata Sierra ◽  
Rafael Reyes Requena ◽  
María Fátima Moreno Pérez
Keyword(s):  
Drip Irrigation ◽  
Sandy Loam ◽  
Soil Layer ◽  
Small Variation ◽  
Original Material ◽  
Se Spain ◽  
Horticultural Crops ◽  
Greenhouse Soils ◽  
Irrigation Control ◽  
Definition Of

<p>The “enarenado” (sand-covering soil) is a technique used in greenhouses located in the southeast of Spain that consists of placing a layer of soil between 20 and 40 cm above the original material, a thin layer of organic matter and above it a layer of sand of about 5 to 10 cm.</p><p>It is necessary to know the shape of the wet bulb produced by the emitters for a correct design and management of the drip irrigation systems. In stratified soils, as in the case of “enarenado” soils, the distribution of water can change substantially with respect to the case of homogeneous soils. The objective of this work is to present the methodology of data acquisition and the actions carried out so far to obtain a model that precisely defines the evolution of humidity in wet bulbs generated in “enarenado” soils characteristic of intensive horticultural crops.</p><p>The tests have been carried out at the facilities of the IFAPA Center La Mojonera, Almería, SE Spain. The textures of the added soils are sandy loam and clay loam, representative of the horticultural crops of Almeria. The crop was pepper , Mazo variety, planted on September 15, 2018 in the two selected greenhouses. The irrigation is automatic, with drippers of nominal flow Qn = 3 l / h, self-compensating, anti-drainage of Netafim. Irrigation control is carried out using classic tensiometers with built-in pressure transducer.</p><p>The humidity has been measured at 10 points distributed around a dripper, 7 probes at 5 cm deep in the added soil layer and 3 probes at 18 cm depth, near the original soil layer. The sensor used is TE5 Decagon. The plantation frame coincides with that of the drippers, Sg = 50 cm and Sr = 120 cm, for this reason the probes were placed up to half of the plantation frame.</p><p>The data collected show a small variation in humidity over time. That is, the added soil, with a clayey texture, quickly redistributes moisture and the probes register very small variations.</p><p>Once the values specified in the methodology have been measured, the theoretical humidity retention curves of greenhouse soils have been calibrated. With the data collected, the system has been simulated by completing the fields that the Hydrus model needs. This operation has been specified in the definition of a simple, multi-layered 3D model. In general, the model predicts moisture behavior well in the conditions set.</p>

scholarly journals Water supply intensity during drip irrigation of vegetable crops

2021 ◽  
Vol 282 ◽  
pp. 05008
Author(s):  
S.A. Kurbanov ◽  
M.M. Dzhambulatov ◽  
V.V. Borodychev ◽  
D.S. Magomedova
Keyword(s):  
Flow Rate ◽  
Drip Irrigation ◽  
Sandy Loam ◽  
Soil Layer ◽  
Field Research ◽  
Moisture Regime ◽  
Vegetable Crops ◽  
Irrigation Rate ◽  
Chestnut Soils ◽  
Irrigation Water Use

The paper presents the materials of field research on the study of the regularities of the development of moisture outlines on light soils during drip irrigation of vegetable crops. The correlation is found between the depth of the moistened layer and the area of the moistening outlines on the pre-irrigation threshold of the moisture content of the active soil layer, irrigation standards and the flow rate of drippers, which gives an opportunity to decline the unproductive water consumption for filtration. It is found that in light loamy and sandy loam light chestnut soils, for guaranteed rule of the moisture regime, on onion crops, it is essential to maintain the pre-irrigation threshold of 80% HB with the irrigation rate of 200 m3 / ha with the flow rate of drip water outlets of 2.8 l / h, and the depth of irrigation of 120 m3/ha with the flow rate of discharge outlets of 1.7 l/h, correspondingly. In irrigation of tomatoes grown on light-loamy light-chestnut soils, it is appropriate to apply the irrigation rate of 180 m3 / ha, which provides the level of pre-irrigation humidity in the layer of 0.6 m not lower than 80% HB, the formation of the required characteristics of the moisture contour (depth of 0.62 m and diameter of 0.37 m), as well as an enhance in the efficiency of irrigation water use by 11.1%. The results can be applied in the design of drip irrigation systems for vegetable crops.

scholarly journals Assessment of Seasonal Variability in Soil Nutrients and Its Impact on Soil Quality under Different Land Use Systems of Lower Shiwalik Foothills of Himalaya, India

2021 ◽  
Vol 13 (3) ◽  
pp. 1398
Author(s):  
Tavjot Kaur ◽  
Simerpreet Kaur Sehgal ◽  
Satnam Singh ◽  
Sandeep Sharma ◽  
Salwinder Singh Dhaliwal ◽  
...  
Keyword(s):  
Land Use ◽  
Soil Quality ◽  
Surface Soil ◽  
Sandy Loam ◽  
Monsoon Season ◽  
Soil Layer ◽  
Seasonal Effects ◽  
Land Use Systems ◽  
Post Monsoon ◽  
Significant Difference

The present study was conducted to investigate the seasonal effects of five land use systems (LUSs), i.e., wheat–rice (Triticum aestivum—Oryza sativa) system, sugarcane (Saccharum officinarum), orange (Citrus sinensis) orchard, safeda (Eucalyptus globules) forest, and grassland, on soil quality and nutrient status in the lower Satluj basin of the Shiwalik foothills Himalaya, India. Samples were analyzed for assessment of physico-chemical properties at four soil depths, viz., 0–15, 15–30, 30–45, and 45–60 cm. A total of 120 soil samples were collected in both the seasons. Soil texture was found to be sandy loam and slightly alkaline in nature. The relative trend of soil organic carbon (SOC), macro- and micro-nutrient content for the five LUSs was forest > orchard > grassland > wheat–rice > sugarcane, in the pre- and post-monsoon seasons. SOC was highly correlated with macronutrients and micronutrients, whereas SOC was negatively correlated with soil pH (r = −0.818). The surface soil layer (0–15 cm) had a significantly higher content of SOC, and macro- and micro-nutrients compared to the sub-surface soil layers, due to the presence of more organic content in the soil surface layer. Tukey’s multiple comparison test was applied to assess significant difference (p < 0.05) among the five LUSs at four soil depths in both the seasons. Principle component analysis (PCA) identified that SOC and electrical conductivity (EC) were the most contributing soil indicators among the different land use systems, and that the post-monsoon season had better soil quality compared to the pre-monsoon season. These indicators helped in the assessment of soil health and fertility, and to monitor degraded agroecosystems for future soil conservation.

The SWORFISH Project Approach for Modeling Wood Material Modifications in Timber Structures

2013 ◽  
Vol 778 ◽  
pp. 418-423
Author(s):  
Jakub Sandak ◽  
Anna Sandak ◽  
Mariapaola Riggio ◽  
Ilaria Santoni ◽  
Dusan Pauliny
Keyword(s):  
Experimental Data ◽  
Expert Knowledge ◽  
Surface Finishing ◽  
Special Focus ◽  
Original Material ◽  
Timber Structures ◽  
Wood Material ◽  
Project Approach ◽  
Special Software ◽  
Definition Of

A special software simulating changes to wood due to various processes (either treatment or degradation) has been developed within the SWORFISH (Superb Wood Surface Finishing) project. The definition of the material modifications due to processes is based on the expert knowledge and/or experimental data. The dedicated algorithm simulates material modifications (with a special focus on surface) taking into account original material characteristics (evaluated by means of NDT techniques) and setting of process parameters. In this way, it is possible to analyze the sequence of processes (i.e. material modifications) and to estimate properties of the resulting product. Two case studies are presented for illustration of the potential uses of the SWORFISH approach in the field of timber structures.

scholarly journals Digital technologies for optimization of moisture parameters of calculated soil’s layer

2021 ◽  
pp. 86-89
Author(s):  
Dmitry Aleksandrovich Solovyev ◽  
Viktor Vladislavovich Korsak ◽  
Galina Nikolaevna Kamyshova ◽  
Olga Nikolaevna Mityureva ◽  
Pavel Olegovich Terekhov
Keyword(s):  
Programming Languages ◽  
Control Systems ◽  
Digital Technology ◽  
Soil Layer ◽  
Digital Technologies ◽  
Irrigated Crops ◽  
Irrigation Control ◽  
Irrigation Technologies ◽  
High Level ◽  
Precision Irrigation

The article presents the results of the development of a digital technology for optimizing the parameters of moisture in the calculated soil layer. The introduction of precision irrigation technologies requires the development of new approaches to the development of decision support systems for their technical implementation in modern high-level programming languages. The developed computer program for determining the optimal moisture parameters of the calculated soil layer for the main irrigated crops of the Saratov region is easy to use and easily integrated into digital automated irrigation control systems.

scholarly journals Predicting Wetting Patterns in Soil from a Single Subsurface Drip Irrigation System

2019 ◽  
Vol 25 (9) ◽  
pp. 41-53
Author(s):  
Heba Najem Abid ◽  
Maysoon Basheer Abid
Keyword(s):  
Drip Irrigation ◽  
Sandy Loam ◽  
Irrigation System ◽  
Subsurface Drip Irrigation ◽  
Statistical Parameters ◽  
Model Efficiency ◽  
Loam Soil ◽  
Wetted Area ◽  
Soil Wetting ◽  
Subsurface Drip

Soil wetted pattern from a subsurface drip plays great importance in the design of subsurface drip irrigation (SDI) system for delivering the required water directly to the roots of the plant. An equation to estimate the dimensions of the wetted area in soil are taking into account water uptake by roots is simulated numerically using HYDRUS (2D/3D) software. In this paper, three soil textures namely loamy sand, sandy loam, and loam soil were used with three different types of crops tomato, pepper, and cucumber, respectively, and different values of drip discharge, drip depth, and initial soil moisture content were proposed. The soil wetting patterns were obtained at every thirty minutes for a total time of irrigation equal to three hours. Equations for wetted width and depth were predicted and evaluated by utilizing the statistical parameters (model efficiency (EF), and root mean square error (RMSE)). The model efficiency was more than 95%, and RMSE did not exceed 0.64 cm for three soils. This shows that evolved formula can be utilized to describe the soil wetting pattern from SDI system with good accuracy.      

Hydraulic characterization of low flow drip irrigation emitters used in intensive horticultural crops in Almeria (Spain)

2021 ◽  
Author(s):  
María Fátima Moreno-Pérez ◽  
Rafael Baeza-Cano ◽  
José Roldán-Cañas ◽  
Gema Cánovas-Fernández ◽  
Rafael Reyes-Requena
Keyword(s):  
Drip Irrigation ◽  
Low Flow ◽  
Limiting Factor ◽  
Fundamental Parameters ◽  
Horticultural Crops ◽  
Hydraulic Behaviour ◽  
Use Efficiency ◽  
Manufacturing Variation ◽  
Very High

&lt;p&gt;In the present work, a selection of drip irrigation emitters used in greenhouse horticultural crops in the province of Almeria, Spain, were hydraulically evaluated, studying their hydraulic behavior and whether they meet with quality standards. Since manufacturers are offering lower flow emitters less spaced, all drippers tested are low flow. The hydraulic characterization will indicate the discharge and emission uniformity of the manufactured emitters, which are the fundamental parameters for the study of water use efficiency in drip irrigation. In the province of Almeria, water is a limiting factor due to the existence of a semi-arid climate, and, in addition, these limited water resources are used by intensive agriculture which causes a high consumption of these resources.&lt;/p&gt;&lt;p&gt;In total, 21 emitters have been evaluated, including all possible drippers according to their type of insertion (inline, pinched or online and interlinea), hydraulic behaviour (non-compensating and self-compensating) and, within the compensating ones, (anti-draining and non anti-draining). Its flow rates are between 1 and 2.4 l/h, except for a non-compensating interlina emitter of 3.8 l/h.&lt;/p&gt;&lt;p&gt;To carry out these tests, the criteria of the ISO 9261:2004 standard have been followed, calculating the coefficient of manufacturing variation and the emitter discharge equation on a test bench located in the La Mojonera Centre (Almeria) of the IFAPA (Andalusian Institute of Agricultural and Fishing Research and Training).&lt;/p&gt;&lt;p&gt;The results of this study show very good behavior in most of the emitters, and, as a consequence, a low coefficient of manufacturing variation has been obtained. The discharge equation obtained in the laboratory shows a low emisi&amp;#243;n exponent in the self-compensating emitters, being, therefore, the compensation of the pressures very high in all cases. No statistically significant differences have been found between self-compensating and non-compensating emitters by analysing their manufacturing variation coefficients. Nor have any significant differences been found between self-compensating emitters according to whether they are anti-draining or non-anti-draining, considering also the coefficient of variation. In anti-draining emitters, all closing pressures are not satisfied according to the standard, and are exceeded with very high values. The opening pressure is met for two of the four emitters, and one of those that does not meet it does so with a very large value.&lt;/p&gt;

Defining the Individual

2010 ◽  
Author(s):  
Niall Sharples
Keyword(s):  
Iron Age ◽  
Soil Layer ◽  
Human Remains ◽  
Human Bone ◽  
Cultural Tradition ◽  
Left Femur ◽  
Southern England ◽  
Socially Constructed ◽  
Definition Of ◽  
The Individual

During the 1985 excavation at Maiden Castle (Sharples 1991a), a large grain storage pit cut into the back of the rampart of the Early Iron Age hillfort was excavated. About half way down the fill of that pit the left femur of a mature adult was exposed. This bone was lying in a relatively sterile soil layer and it was not marked by any special finds or careful constructions; in many respects it could easily be dismissed as a discovery with little significance. Fifty years ago such bones would have been regarded as accidental losses, simply rubbish conveniently disposed of in a handy receptacle. It could be an indication that excarnation was the general means of disposal and that this occurred close to or actually inside settlements, but it might also indicate the accidental disturbance of human remains in graves located at the hillfort. In recent years we have come to understand that these deposits are much more significant. A number of archaeologists (Whimster 1981; C. Wilson 1981; Cunliffe 1992) came to realize that the presence of human remains on Iron Age settlements was a distinct cultural tradition characteristic of central southern England. The work of J. D. Hill (1995b) has enhanced our understanding of this phenomenon by emphasizing that the deposition of human remains is part of a complex suite of actions which involves the arrangement of different categories of material in carefully placed deposits. The process of deposition was clearly intimately involved in the definition of social relationships in the Iron Age of central southern England. It is difficult to imagine that if we, as archaeologists, could immediately recognize a human bone, our ancient pit diggers could not. The placement of this bone was a deliberate act, and the location of this deposit was carefully chosen. Hill (1995b) has shown that these pit deposits were carefully structured. Human remains are normally found in layers that are largely sterile, but a pit chosen for the deposition of human bone will normally have fills containing other carefully selected deposits. These mark the pit as a bank of socially constructed material.

scholarly journals Modeling of Fertilizer Transport for Various Fertigation Scenarios under Drip Irrigation

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 893 ◽  
Author(s):  
Romysaa Elasbah ◽  
Tarek Selim ◽  
Ahmed Mirdan ◽  
Ronny Berndtsson
Keyword(s):  
Drip Irrigation ◽  
Sandy Loam ◽  
Loamy Sand ◽  
Nitrogen Fertilizers ◽  
Subsurface Drip Irrigation ◽  
Application Rates ◽  
Use Efficiency ◽  
Phosphorus And Potassium ◽  
Subsurface Drip ◽  
The Impact

Frequent application of nitrogen fertilizers through irrigation is likely to increase the concentration of nitrate in groundwater. In this study, the HYDRUS-2D/3D model was used to simulate fertilizer movement through the soil under surface (DI) and subsurface drip irrigation (SDI) with 10 and 20 cm emitter depths for tomato growing in three different typical and representative Egyptian soil types, namely sand, loamy sand, and sandy loam. Ammonium, nitrate, phosphorus, and potassium fertilizers were considered during simulation. Laboratory experiments were conducted to estimate the soils’ adsorption behavior. The impact of soil hydraulic properties and fertigation strategies on fertilizer distribution and use efficiency were investigated. Results showed that for DI, the percentage of nitrogen accumulated below the zone of maximum root density was 33%, 28%, and 24% for sand, loamy sand, and sandy loam soil, respectively. For SDI with 10 and 20 cm emitter depths, it was 34%, 29%, and 26%, and 44%, 37%, and 35%, respectively. Results showed that shallow emitter depth produced maximum nitrogen use efficiency varying from 27 to 37%, regardless of fertigation strategy. Therefore, subsurface drip irrigation with a shallow emitter depth is recommended for medium-textured soils. Moreover, the study showed that to reduce potential fertilizer leaching, fertilizers should be added at the beginning of irrigation events for SDI and at the end of irrigation events for DI. As nitrate uptake rate and leaching are affected by soil’s adsorption, it is important to determine the adsorption coefficient for nitrate before planting, as it will help to precisely assign application rates. This will lead to improve nutrient uptake and minimize potential leaching.

Effect of available solar irradiance on vertical farming in semi-open urban places

2020 ◽  
Vol 10 (2) ◽  
pp. 717-726
Author(s):  
M. Moniruzzaman ◽  
K. K. Saha ◽  
M. M. Rahman ◽  
M. M. H. Oliver
Keyword(s):  
Drip Irrigation ◽  
Solar Irradiance ◽  
Sandy Loam ◽  
Irrigation System ◽  
Water Productivity ◽  
Field Capacity ◽  
Direct Sunlight ◽  
Lighting Conditions ◽  
Vertical Farming ◽  
Long Run

Building a vertical farm in unused residential and commercial spaces is a challenge. It is particularly hard to decide upon a space where varying degrees of lighting conditions may prevail at different times of a day. This experiment was focused on how innovative micro-irrigation technology could be coupled with vertical farms. In this regard, three storied racks were designed to accommodate multiple one-feet-square tubs large enough to hold five Indian spinach (BARI Puishak- 2) plants at a time. Sandy loam soil was used for farming along with recommended doses of fertilizers. Different lighting conditions (2- 145 W/m2 average solar irradiance) were employed on the fifth floor of an urban building. Drip emitters were coupled in the system for irrigation. The management allowed deficit was kept to a maximum of 50% of the readily available moisture below the field capacity. The results suggested that drip irrigation systems provide higher water productivity (up to 31.82 kg/m3) compared to the in-field conditions when BARI Puishak-2 is grown in vertical farming. Water productivity of spinach was improved by optimized set-up of a drip irrigation system. The study also concluded that vertical farming is only suitable for indoor places where plenty of direct sunlight or diffused sunlight (not below 70 W/m2) is available. The economic analysis suggests that vertical farms under direct sunlight can be made profitable (BCR>1) in the long run.

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