To see the other types of publications on this topic, follow the link: Drip Irrigation, low pressure.
Journal articles on the topic 'Drip Irrigation, low pressure'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Drip Irrigation, low pressure.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Mostafa, H., and H. H. Thörmann. "On-farm evaluation of low-pressure drip irrigation system for smallholders." Soil and Water Research 8, No. 2 (May 15, 2013): 87–95. http://dx.doi.org/10.17221/29/2012-swr.
Full textAbstract:
The aim of this paper was to evaluate the performance of a low-pressure drip system (LPS) for three years of service, to calculate the consumptive working time and costs of maintenance and laterals retrieving before harvesting and to determine benefits and problems with drip irrigation. Drip irrigation provides the opportunity to save water and the potential to increase net income by applying water at the right quantity and at the right time. Small to medium fields would benefit from the LPS irrigation system which has the ability to distribute the amount of water applied. LPS is a well-researched system for drip irrigation, typically that available for furrow irrigated crops. There are significant agronomic advantages of using a low-pressure, low-flow drip system. These advantages translate into measured improved distribution uniformity when compared to flood irrigated crops and energy savings compared to flood and sprinkler irrigated crops. The old (reused) drip line leads to a decrease in distribution uniformity and an increase in costs, when the distribution uniformity decreased by 10.5 and 21.6% for reusing the laterals in the second and third year, respectively. Moreover, the cost of repairing laterals was more than 5 and 6.5 times higher for both the 2<sup>nd</sup> and 3<sup>rd</sup> season. Many disadvantages of drip lines retrieval can be observed, because labour and maintenance are more intensive; there is a risk of mechanical damage to laterals especially if they are reused; increased management skills and experience are needed; and increased retrieval costs arise season after season.
2
Domullodzhanov, Daler. "Drip irrigation technology for potatoes through applying low-pressure semistationary small-capacity." Melioration and Water Management, no. 6 (January 22, 2021): 4–8. http://dx.doi.org/10.32962/0235-2524-2020-6-4-8.
Full textAbstract:
The article describes the results of field and laboratory experiments on the study of the technology of drip irrigation of potatoes via using the semi-stationary low-pressure small-capacity drip irrigation system (LDIS) developed by us. Reinforced aluminium micro-tubes ensure uniform watering. Depending on the annual precipitation sufficiency, the potatoes irrigation requirements 1700…3400 m3/ha, the number of irrigations varied from 10 to 20 times, and the yield was between 54…58,2 tons per ha.
3
Sokol, Julia, Susan Amrose, Vinay Nangia, Samer Talozi, Elizabeth Brownell, Gianni Montanaro, Khaled Abu Naser, et al. "Energy Reduction and Uniformity of Low-Pressure Online Drip Irrigation Emitters in Field Tests." Water 11, no. 6 (June 7, 2019): 1195. http://dx.doi.org/10.3390/w11061195.
Full textAbstract:
A promising way of addressing the issue of growing water scarcity is through wider use of drip irrigation, which delivers water and fertilizer to crops in a slow, targeted manner, and has been shown to increase yields and water use efficiency. Yet, drip irrigation system adoption is low, primarily due to the high capital cost of the pressurized piping network and the pump, and operating energy cost. Lowering the water pressure needed for drip emitters to deliver water can reduce both capital and operating costs of drip systems. Here we present the results from field trials of new pressure-compensating online drip emitters that operate with a minimum compensating inlet pressure of 15 kPa (0.15 bar), in comparison to typical commercial emitters with minimum pressures of 50–100 kPa (0.5–1.0 bar). The field trials were carried out on nine farms in Morocco and Jordan over the course of one irrigation season with freshwater and treated wastewater. Low-pressure emitters are shown to reduce hydraulic energy per unit volume of water delivered by 43% on average compared to commercial emitters, without significantly sacrificing water emission uniformity (low-pressure emitters show uniformities of 81–91%, compared to 87–96% for commercial emitters). This energy reduction could lead to savings of 22–31% in the capital cost of a pump and emitters and the energy cost for a typical drip irrigation system. Thus, the low-pressure online emitters can be used as substitutes to commercial emitters that require higher water pressures, leading to reduced environmental impact and lower system costs.
4
Rowell, Brent, and Mar Lar Soe. "Design, Introduction, and Extension of Low-Pressure Drip Irrigation in Myanmar." HortTechnology 25, no. 4 (August 2015): 422–36. http://dx.doi.org/10.21273/horttech.25.4.422.
Full textAbstract:
Drip irrigation is used extensively by both large and small commercial horticultural crop growers in most developed countries where benefits include not only high water use efficiency, but also higher yields, improved product quality, and reduced incidence of foliar disease. Drip systems are still relatively new and expensive in Southeast Asia, and it is primarily wealthier farmers who currently enjoy its benefits. There are also significant perceptual barriers to adoption as many farmers are accustomed to applying copious amounts of water to horticultural crops and are unfamiliar with drip or their crops’ actual water requirements. As a nongovernmental organization whose mission is to help boost small farm incomes, International Development Enterprises (IDE) began experimenting with low-pressure, low-cost gravity-fed drip systems in Myanmar (Burma) in 2006. While the basic design was similar to microtube drip systems of the 1960s, local improvements included filters designed for low pressures, easy-to-use fittings, and inexpensive collapsible header tanks. Our system was optimized for operation on small but commercial-scale plots using pressures as low as 1 psi or only ≈1/10th of that used for conventional drip irrigation. Extension support materials included illustrated installation guides, system design software, videos, testing/filtering of dissolved iron, and easy-to-use water requirement calculators. After hundreds of controlled and farmers’ field tests, our locally manufactured drip sets were offered for sale by private dealers throughout Myanmar in 2009. Incremental system improvements coupled with a strong on-farm demonstration and farmer education program resulted in the successful introduction and widespread adoption of drip irrigation in Myanmar.
5
Kalashnikov, Aleksander, Nurlan Abduramanov, Pavel Kalashnikov, Aigul Bayzakova, and Nurzhau Rysmahanov. "Optimization of Low-Pressure Hydrocyclone Sizes for Drip Irrigation System." Journal of Advanced Research in Dynamical and Control Systems 12, no. 05-SPECIAL ISSUE (May 30, 2020): 191–98. http://dx.doi.org/10.5373/jardcs/v12sp5/20201748.
Full text
6
Wang, Yalin, Xueliang Ju, Shijiang Zhu, and Meng Li. "Simulation of local head loss of drip-irrigation tape with integrated in-line emitters as a function of cross section." Spanish Journal of Agricultural Research 18, no. 4 (November 23, 2020): e0210. http://dx.doi.org/10.5424/sjar/2020184-15767.
Full textAbstract:
Aim of study: To investigate how the cross section of a drip-irrigation tape affects local head loss.Area of study: The work was carried out in the laboratory of Irrigation hydraulics, College of Water Conservancy and Environment, Three Gorges University, Yichang, Hubei province.Material and methods: Tapes with six different wall thicknesses were studied experimentally to determine the relationship between cross-section deformation, wall thickness, and pressure. Based on the experimental results, we determined the factors that influence local head loss in drip-irrigation tapes by numerical simulation and dimensional analysis.Main results: The cross-sectional shape of the drip-irrigation tape varied with pressure: under low pressure, the cross section was nearly elliptical. The cross-sectional shape of the tape strongly influenced the local head loss, which was inversely proportional to the 0.867th power of the flattening coefficient of the drip irrigation tape. We expressed the local head loss of a drip-irrigation tape equipped with integrated in-line emitters by considering the deformation of the cross section. Under the conditions used in this study, when the cross section is circular, the ratio of local head loss to frictional head loss was about 10% but, when the cross section is elliptical, this ratio increased to 15%.Research highlights: The shape of the cross section of a drip-irrigation tape is nearly elliptical under low pressure. Local head loss is inversely proportional to the 0.867th power of that is the flatting coefficient of the drip-irrigation tape. Local head loss is about 1.5 times for elliptical tape than circular tape.
7
Yan, Xin Fang, and Jun Cang Tian. "Study of Application on Reverse Osmosis Concentrated Water Circulation in Desert Greenhouse." Applied Mechanics and Materials 409-410 (September 2013): 287–93. http://dx.doi.org/10.4028/www.scientific.net/amm.409-410.287.
Full textAbstract:
Aiming at the problem of concentrated water discharge amount is larger and the recovery rate is low in desert greenhouse for desalination of brackish water,Using reverse osmosis concentrated water circulation system.The results showed: With less dense water emissions, System desalinization rate decreases, system recovery rate increases, water flow in the system decreases, the system water pressure increases. In this test, when dense water emissions is 0.81m3/h, System desalinization rate reaches up to 91%, system recovery rate reached up to 81%, saving water above 20%. Major ion SO42-, Cl-, Ca2+ and Mg2+ removal rates are 96.2%, 92.7%,100% and 100%. The order of yield and benefit on Planting pepper are: wheel irrigation drip > water drip > mixed irrigation drip > raw water drip irrigation under different irrigation modes.Benefit-cost ratio of wheel irrigation drip ,water drip and mixed irrigation drip are 17.68,13.61 and 4.61.
8
Muxammadiyeva, Matluba, and Iftixor Ergashev. "IMPLEMENTATION OF THE WATER USE PLAN PROCEDURES, MEASURES AND WATER USE." JOURNAL OF AGRO PROCESSING 6, no. 2 (June 30, 2020): 50–58. http://dx.doi.org/10.26739/2181-9904-2020-6-9.
Full textAbstract:
If we look at the existing irrigation methods used today in the country, then they are divided into: ground, rainfall, underground or underground, drip and spray. Basically, they are transferred to the irrigation field in two forms: through gravity and pressure irrigation systems. Naturally, a gravity irrigation system is economically more expensive than a low pressure irrigation system. However, from a performance appraisal stand point, pressure irrigation methods are less efficient and have serious disadvantages
9
Chirgwin, Gavin Andrew, and Bruce Sutton. "A low-cost, high-precision drip emitter suitable for low-pressure micro-irrigation systems." Irrigation Science 37, no. 6 (June 18, 2019): 725–35. http://dx.doi.org/10.1007/s00271-019-00641-7.
Full text
10
Al-Mefleh, Naji K., Samer Talozi, and Khaled Abu Naser. "Assessment of Treated Wastewater Reuse in Drip Irrigation under Different Pressure Conditions." Water 13, no. 8 (April 9, 2021): 1033. http://dx.doi.org/10.3390/w13081033.
Full textAbstract:
This study aims to investigate the influence of treated wastewater (TWW) on the hydraulic performance of drip irrigation emitters. A field experiment was conducted in order to test two types of online emitters, a low pressure (LP) and a standard pressure (SP), at different working pressures (0.25 bar, 0.50 bar, and 1.00 bar) using TWW. The emitters were initially evaluated in the laboratory and the field for the discharge exponent (X), discharge coefficient (Kd), average emitter discharge (Qavg), coefficient of variation (CV), distribution uniformity (DU), the mean discharge ratio (Dra), and the main degree of clogging (DC). The main effect of the emitters on the hydraulic parameters of irrigation performance was not significant, while the operational pressure and operational time of irrigation had a significant effect. For the LP emitter, the average emitter discharge was 7.6, 7.7, and 7.8 Lh−1 at 0.25, 0.50, and 1.00 bar, respectively. For the SP emitter, the average emitter discharge was 7.6, 7.8, and 7.8 Lh−1 at 0.25, 0.50, and 1.00 bar, respectively. The EU values for the LP and SP emitters varied from low to moderate at 0.25 bar, as the EU values at 0.50 and 1.00 bar were considered high for both emitter types.
11
Oliveira, Cleomar Ferreira de, Marconi Batista Teixeira, Adriana Ramos, Renato Moreira da Silva, Pedro Henrique Pinto Ribeiro, and José Antônio Frizzone. "PORTABLE SAND FILTER FOR SMALL DRIP IRRIGATION SYSTEMS." IRRIGA 21, no. 1 (June 18, 2018): 90. http://dx.doi.org/10.15809/irriga.2016v21n1p90-103.
Full textAbstract:
PORTABLE SAND FILTER FOR SMALL DRIP IRRIGATION SYSTEMS CLEOMAR FERREIRA DE OLIVEIRA1; MARCONI BATISTA TEIXEIRA2*; ADRIANA RAMOS3; RENATO MOREIRA DA SILVA4; PEDRO HENRIQUE PINTO RIBEIRO5 E JOSÉ ANTÔNIO FRIZZONE6 1 Engenheiro Agrônomo, Prof. Dr. IFMinas Gerais - Campus Muzambinho, MG.2 Engenheiro Agrônomo, Prof. Dr. IFGoiano - Campus Rio Verde, GO. *E-mail: marconibt@gmail.com3 Engenheira Agrônoma, Profa. Dra. Universidade Estadual de Santa Cruz – Ilhéus, BA.4 Engenheiro Agrônomo, Doutor, Departamento de Engenharia de Biossistemas, LEB - ESALQ/USP, Piracicaba - SP.5 Tecnólogo em Irrigação e Drenagem, Doutorando, Departamento de Engenharia Rural, UNESP/FCA, Botucatu, SP.6 Engenheiro Agrônomo, Prof. Titular, Departamento de Engenharia de Biossistemas, LEB - ESALQ/USP, Piracicaba - SP. 1 ABSTRACT Filters in drip irrigation systems are fundamental to ensure effective control of water quality and to reduce clogging of emitters. Current study aims at constructing a low cost portable sand filter for small localized irrigation systems (up to 1.0 ha) and at determining its head loss due to flow. Tests were carried out in the Hydraulic Laboratory of Biosystems Engineering Department of Agriculture School “Luiz de Queiroz”, University of São Paulo. Magnetic-induction Conaut Krohne model IFS 4000 w/6 with IFC 090 D signal convert of discharge, reading range between 0 and 90 m3.h-1 and 99% precision, was used for flow rate measurements. Pressure loss at each observation point was determined indirectly by two differential pressure gauges with a mercury column. A set of 20 flow readings was performed in three replications. Results showed that maximum filter discharge complied with ASAE guidelines and the cost of materials for manufacture of the filter was U$ 382.15. Linear mathematical model adequately describes the loss of pressure of the sand filter due to flow variation. Rates of minimum and maximum flow recommended range between 0.0257 m3.h-1 and 0.556 m3.h-1, and thus may satisfy small trickle irrigation projects. Keywords: Filtration, water quality, head loss, flow rate.
12
Bordovsky, James P. "Low-Energy Precision Application (LEPA) Irrigation: A Forty-Year Review." Transactions of the ASABE 62, no. 5 (2019): 1343–53. http://dx.doi.org/10.13031/trans.13117.
Full textAbstract:
Abstract. The low-energy precision application (LEPA) irrigation concept was developed 40 years ago (ca. 1978) to address the depletion of irrigation water from the Ogallala Aquifer and the sharp increase in pumping costs caused by the 1970s fuel crisis occurring at that time in the Texas High Plains. The LEPA method applies water to the soil surface at low pressure using a tower-truss irrigation system that continually moves through the field. This method brought changes in irrigation equipment and management that resulted in improvements in water productivity, particularly in semi-arid locations with diminishing water supplies. A review of published information pertaining to LEPA history, evaluation, and usage was performed. On landscapes of less than 1% slope, negative crop yield effects caused by irrigation runoff and start-stop system alignment were overcome with appropriately spaced basins, or furrow checks, and multiple irrigations over the course of the growing season. No consistent yield advantage at any level of irrigation was documented by placing water in every furrow (1 m spacing) compared to alternate furrows (2 m spacing). In irrigation treatments having =50% of the estimated full irrigation quantity, LEPA resulted in a 16% yield increase over sprinkler methods, although subsurface drip irrigation (SDI) resulted in a 14% yield increase over LEPA. At irrigation levels >50% of full irrigation, crop yields of sprinkler treatments were only slightly less than those of LEPA, and SDI yields were 7% greater than LEPA. The LEPA irrigation method was the catalyst for innovations in chemigation, no-till planting, and site-specific irrigation. As irrigation water becomes more limited, use and proper management of optimum irrigation methods will be critical. Keywords: Basin tillage, Chemigation, Evapotranspiration, Irrigation methods, LEPA, Low-energy precision application, Runoff, Spray irrigation, Sprinkler irrigation, Uniformity, Water use efficiency.
13
Thompson, E. J., G. P. Merkley, A. A. Keller, and S. L. Barfuss. "Experimental Determination of the Hydraulic Properties of Low-Pressure, Lay-Flat Drip Irrigation Systems." Journal of Irrigation and Drainage Engineering 137, no. 1 (January 2011): 37–48. http://dx.doi.org/10.1061/(asce)ir.1943-4774.0000269.
Full text
14
Poh, Bee Ling, Aparna Gazula, Eric H. Simonne, Robert C. Hochmuth, and Michael R. Alligood. "Use of Reduced Irrigation Operating Pressure in Irrigation Scheduling. II. Effect of Reduced Irrigation System Operating Pressure on Drip-tape Flow Rate, Water Application Uniformity, and Soil Wetting Pattern on a Sandy Soil." HortTechnology 21, no. 1 (February 2011): 22–29. http://dx.doi.org/10.21273/horttech.21.1.22.
Full textAbstract:
For shallow-rooted vegetables grown in sandy soils with low water-holding capacity (volumetric water content <10%), irrigation water application rate needs to provide sufficient water to meet plant needs, to avoid water movement below the root zone, and to reduce leaching risk. Because most current drip tapes have flow rates (FRs) greater than soil hydraulic conductivity, reducing irrigation operating pressure (OP) as a means to reduce drip emitter FR may allow management of irrigation water application rate. The objectives of this study were to determine the effect of using a reduced system OP (6 and 12 psi) on the FRs, uniformity, and soil wetted depth and width by using three commercially available drip tapes differing in emitter FR at 12 psi (Tape A = 0.19 gal/h, Tape B = 0.22 gal/h, and Tape C = 0.25 gal/h). Reducing OP reduced FRs (Tape A = 0.13 gal/h, Tape B = 0.17 gal/h, and Tape C = 0.16 gal/h) without affecting uniformity of irrigation at 100 and 300 ft lateral runs. Flow rate was also reduced at 300-ft lateral length compared with 100 ft for all three tapes. Uniformity was reduced [“moderate” to “unacceptable” emitter flow variation (qvar) and “moderate” coefficient of variation (cv)] at 300 ft for Tape B and C compared with “good” qvar and “moderate” to “excellent” cv at 100 ft. Using soluble dye as a tracer, depth (D) of the waterfront response to irrigated volume (V) was quadratic, D = 4.42 + 0.21V − 0.001V2 (P < 0.01, R2 = 0.72), at 6 psi, with a similar response at 12 psi, suggesting that depth of the wetted zone was more affected by total volume applied rather than by OP itself. The depth of the wetted zone went below 12 inches when V was ≈45 gal/100 ft, which represented ≈3 h of irrigation at 6 psi and 1.8 h of irrigation at 12 psi for a typical drip tape with FR of 0.24 gal/h at 12 psi. These results show that, for the same volume of water applied, reduced OP allowed extended irrigation time without increasing the wetted depth. OP also did not affect the width (W) of the wetted front, which was quadratic, W = 6.97 + 0.25V − 0.002V2 (P < 0.01, R2 = 0.70), at 6 psi. As the maximum wetted width at reduced OP was 53% of the 28-inch-wide bed, reduced OP should be used for two-row planting or drip-injected fumigation only if two drip tapes were used to ensure good coverage and uniform application. Reducing OP offers growers a simple method to reduce FR and apply water at rates that match more closely the hourly evapotranspiration, minimizing the risk of leaching losses.
15
Tognetti, R., M. Palladino, A. Minnocci, S. Delfine, and A. Alvino. "The response of sugar beet to drip and low-pressure sprinkler irrigation in southern Italy." Agricultural Water Management 60, no. 2 (May 2003): 135–55. http://dx.doi.org/10.1016/s0378-3774(02)00167-1.
Full text
16
Garabedian, Sahag. "Effects of Nonfumigant Nematicides Applied Through Low-Pressure Drip Irrigation on Control ofMeloidogyne incognitaon Tomatoes." Plant Disease 69, no. 2 (1985): 138. http://dx.doi.org/10.1094/pd-69-138.
Full text
17
Sarker, Hossain, Murad, Biswas, Akter, Rannu, Moniruzzaman, Karim, and Timsina. "Development and Evaluation of an Emitter with a Low-Pressure Drip-Irrigation System for Sustainable Eggplant Production." AgriEngineering 1, no. 3 (July 31, 2019): 376–90. http://dx.doi.org/10.3390/agriengineering1030028.
Full textAbstract:
Drip-irrigation can improve uniformity in water distribution, water use efficiency, and crop productivity in the saline and nonsaline regions of South Asia and in Bangladesh where the availability and quality of water resources are scare for sustainable crop production. However, the currently available drip-irrigation systems (DIS) have limitations especially in the design and field performance of emitters. A new type of emitter with low pressure (gravity) was developed, installed and evaluated using the locally produced materials in two locations (nonsaline and saline zones) of Bangladesh. The emitter discharge rate was measured for the variable operating heads of 1.5, 2, and 2.5 meter (m) with 0%, 1%, and 1.5% slopes with eggplant (Solanum melongena L.), a commonly grown vegetable in the region. The tested parameters of the emitter were manufacturer coefficient of variation (CVm), emission uniformity (EU), coefficient of uniformity (CU), and the statistical uniformity (Us) of water application. Our results reveal that the discharge rates of the emitter varied from 3 to 5 L h−1 under the operating head of 1.5 to 2.5 m with the slope of 0–1.5%, with better performance of the DIS at 2 m operating pressure head and for slopes of 0% and 1%. The CU of all the test parameters was more than 80%, implying that the DIS was designed and installed with appropriate dimensions for the efficient application and distribution of water to the individual plants, with the emitter performance classified as fair to excellent considering water application and distribution, as well as crop yield. The new emitter used for DIS in field conditions showed that the eggplant yield, water use, and water productivity were greater by 4.6%, 38%, and 70%, respectively, compared to farmers’ irrigation practice. We conclude that the DIS has a great prospect to save water, and could be a convenient irrigation water application method for sustainable crop production in saline and nonsaline regions of Bangladesh and similar soil and climatic conditions in South Asia.
18
Zhang, Chao, Yaohu Kang, Shufang Jiang, Shuqin Wan, and Shiping Liu. "Assessment of Hydraulic Performance of Drip-Irrigation Emitters at Low Head Pressures." Journal of Irrigation and Drainage Engineering 137, no. 11 (November 2011): 730–34. http://dx.doi.org/10.1061/(asce)ir.1943-4774.0000363.
Full text
19
Palada, M., A. C. Mercado, M. Roberts, V. B. Ella, M. R. Reyes, A. D. Susila, D. T. Ha, D. L. Wu, and M. Bhattarai. "FARMERS' EXPERIENCES WITH LOW-PRESSURE DRIP IRRIGATION FOR VEGETABLE PRODUCTION IN SOUTHEAST ASIA AND THE PACIFIC." Acta Horticulturae, no. 921 (December 2011): 49–56. http://dx.doi.org/10.17660/actahortic.2011.921.5.
Full text
20
Woltering, Lennart, Ali Ibrahim, Dov Pasternak, and Jupiter Ndjeunga. "The economics of low pressure drip irrigation and hand watering for vegetable production in the Sahel." Agricultural Water Management 99, no. 1 (November 2011): 67–73. http://dx.doi.org/10.1016/j.agwat.2011.07.017.
Full text
21
Thabet, Mohamed. "Drip irrigated Barley (Hordeum vulgare L.) in arid regions of South Tunisia: Plant Growth and Yield Parameters." Turkish Journal of Agriculture - Food Science and Technology 4, no. 6 (June 15, 2016): 470. http://dx.doi.org/10.24925/turjaf.v4i6.470-475.663.
Full textAbstract:
Historically relegated to the status of “poor man’s bread” barley is one of widely cultivated crops in arid regions of south Tunisia for its grain and biomass used as an animal feed and other various purposes. Barley is incorporated into many types of home recipes. Harsh climate and frequent droughts are the great challenge for cereals production so farmers must supply irrigation in order to improve yields. Traditional irrigation techniques are widely used despite their low efficiency. Conversion to drip is encouraged by public services as a measure to save water resources, boost yields and as an adaptation measure to climate change that will cause more pressure on available water resources .The present paper presents results for drip irrigated barley in arid climate of South Tunisia. The study was undertaken at research farm of Institute of Arid Regions in Medenine and tried to replicate current farmer’s practices with the aim to facilitate their conversion to drip irrigation. For full drip irrigated barley (100% irrigation water requirements), following crop variables were recorded according to standard agronomic procedures as described in Daur et al. (2011): Plant height (m); Ears number by square meter at harvest; Number of grains per ear; 1000 grain weight (g); Biological yield (kg.m-2); Grain yield at harvest (g.m-2). Grain yield was 360.75g m-2 which corresponds to 3.61 ton ha-1and Biological yield was 1.014 kg m-2 for a total water amount of 225 mm. These values far exceed those obtained in rainfed agriculture.
22
Jha, Shiva Kumar, Mita Tarafder, Deepak Dhibar, Bhanu Pokharel, Jiban Shrestha, and Keshab Babu Koirala. "Design and Development of Soil Moisture Based Automatic Irrigation System in Nepal." Journal La Multiapp 1, no. 3 (December 2, 2020): 43–53. http://dx.doi.org/10.37899/journallamultiapp.v1i3.197.
Full textAbstract:
A prototype soil moisture based an automated irrigation system were developed at National Maize Research Program in 2018 to study the water requirement of drought tolerant crop genotype. The irrigation system has been controlled by Arduino UNO as a micro controller. The instant soil moisture data were collected either in Excel format or graphical format using internet of things through the programming of Global System for Mobile Communication: Subscriber Identity Module (GSM:SIM card) of Nepal Telecom. The developed automated irrigation system has found maintained the predetermined threshold soil moisture. This automated irrigation system has been developed to make applicable for drip irrigation system which has operated at low water pressure maintained by 1.5² professional-grade solenoid valve. The introduction of this automated irrigation system has developed the base for Nepalese agricultural scientist in designing and promoting irrigation technology to make Nepalese agricultural more sustainable, mechanized and productive.
23
Karlik, John F., J. Ole Becker, and Ursula K. Schuch. "022 Delivery of Gases to the Soil Matrix via Buried Drip Irrigation Tubing." HortScience 34, no. 3 (June 1999): 444E—445. http://dx.doi.org/10.21273/hortsci.34.3.444e.
Full textAbstract:
The impending worldwide restrictions on the use of methyl bromide (MeBr) as a soil fumigant have prompted an intensive search for more-effective methods for delivering MeBr or replacement compounds. Although the majority of agrochemicals are applied in the solid phase or the liquid phase at ambient pressure and temperature, some chemicals, including certain soil fumigants such as MeBr, are gases under normal field conditions. Experiments were conducted to evaluate use of two types of commercial drip irrigation tubing to deliver gases to nontarped planting beds. Air moved through each tubing type immediately after burial; water was not necessary for inflation. Air was also able to move through 40 m of buried rigid drip tubing and through 90 m of buried flat tape that had been used for subsurface drip irrigation for more than 1 year. Mixtures of known ratios of propane and air were introduced into the buried tubing over several time intervals to evaluate gas movement from buried drip tubing into the surrounding soil matrix. Samples were collected from sets of three soil gas sampling tubes placed 15, 30, and 45 cm to the side of the buried tubing and at regular intervals along the length of the tubing, and propane concentrations were quantified by gas chromatography. Tubing lengths and run times affected the magnitudes and uniformity of propane concentrations. Results suggest gas-phase chemicals can be delivered via buried drip-irrigation tubing, but effective distances from the point of introduction will be limited by the low densities and viscosities of gases, and corresponding high rates of escape through tubing emitters.
24
Zhang, Kai, Bo Song, and Delan Zhu. "The Development of a Calculation Model for the Instantaneous Pressure Head of Oscillating Water Flow in a Pipeline." Water 11, no. 8 (July 31, 2019): 1583. http://dx.doi.org/10.3390/w11081583.
Full textAbstract:
Sinusoidal oscillating water flow at low pressure can improve the anti-clogging ability of an emitter in drip irrigation or the water distribution of a nozzle in sprinkler irrigation and reduce the cost and energy consumption of the irrigation system. In this study, the characteristics of instantaneous pressure head attenuation of oscillating water flow along a pipeline have been investigated. By using a complex function to solve the continuity equation and the momentum equation of a pipeline with water hammer motion and using the Darcy–Weisbach formula to estimate the head loss, a calculation model for the instantaneous pressure head of oscillating water flow along a pipeline was developed. The measured value of the amplitude of the pressure head and the average instantaneous pressure head in the experiments have been used to verify the corresponding pressure head calculated by the model. The results show that the amplitude of the pressure head and the average instantaneous pressure head decrease linearly along the pipeline. The calculated value of the amplitude of the pressure head and the average instantaneous pressure head are basically close to the corresponding measured pressure head. From the results of all the tests, the maximum relative error of the calculated and measured value of the amplitude of the pressure head along the pipeline was 9.44%. The maximum relative error of the calculated and measured value of the average instantaneous pressure head along the pipeline was 8.37%. Hence, the model can accurately predict the instantaneous pressure head of oscillating water flow along a pipe and provide a theoretical basis for the application of oscillating water flow in irrigation systems and the design of irrigation pipe networks.
25
Muñoz-Carpena, Rafael, Yuncong C. Li, Waldemar Klassen, and Michael D. Dukes. "Field Comparison of Tensiometer and Granular Matrix Sensor Automatic Drip Irrigation on Tomato." HortTechnology 15, no. 3 (January 2005): 584–90. http://dx.doi.org/10.21273/horttech.15.3.0584.
Full textAbstract:
A low-volume/high frequency (LVHF) soil moisture-based drip irrigation system was tested on a shallow sandy soil at a commercial tomato (Lycopersicon esculentum) farm in southern Florida. Six LVHF irrigation treatments were compared with the standard commercial practice on the farm (control), where a portable pump was used for manual drip irrigation twice each week. In the six LVHF treatments the system was continuously pressurized by means of an electrical pump and a pressure tank, and controlled by an irrigation timer set to irrigate a maximum of five times per day with the irrigation time (i.e., volume) set according to historical evapotranspiration (ET) demands in the area. Two treatments were based on timer schedules, one to supply 100% of the maximum recommended crop water needs in the area based on historical ET (ET-100%), and the other to supply 150% of those needs (ET-150%). The other four treatments were created by interfacing two types of soil moisture sensors (switching tensiometers and granular matrix sensors with control modules) set at two moisture points (wet = 10 kPa, optimal = 15 kPa) in a closed control loop with the irrigation timer programmed at the ET-100% schedule. Results showed that the six LVHF treatments reduced water use while not significantly affecting tomato yields. Switching tensiometers at the 15 kPa set point performed the best (up to 73% reduction in water use when compared to the control, 50% with respect to ET-100%). The results show that water use below historical ET levels can be obtained without sacrificing yield by keeping the root zone moisture at controlled levels with the soil-moisture based system. Routine maintenance was critical for reliable operation of the switching tensiometers. Granular matrix sensor based irrigation behaved erratically, and did not improve water savings compared to ET-100%, indicating that this system was not effective under the conditions of the area due to the sensor's slow response to frequent wetting-rewetting cycles and characteristics of the interface.
26
Melo, Verônica G. M. L., Ana C. S. Araújo, Antonio P. Camargo, Leonardo L. Melo, José A. Frizzone, and Wagner W. A. Bombardelli. "Head Loss in Thin-Walled Drip Tapes with Continuous Labyrinth." Scientific World Journal 2019 (December 10, 2019): 1–11. http://dx.doi.org/10.1155/2019/8640893.
Full textAbstract:
Thin-walled drip tapes with continuous labyrinth have been used for irrigation of vegetables and other short-cycle crops, especially due to their low cost. The continuous labyrinths welded into the pipe inner wall affect the head loss along such emitting pipes. In addition, the flow cross section of thin-walled pipes may change due to the effects of the operating pressure, which also has consequences for the head loss. The objective of this work was to investigate experimentally the friction factor and the head loss on thin-walled drip tapes with continuous labyrinths operated under various pressures. Two models of commercial thin-walled drip tapes with continuous labyrinths were evaluated. Nonperforated samples were used to determine the head-loss equations. The equations were adjusted as a function of flow rate and pressure head at the pipe inlet. Alternatively, the diameter in the Darcy–Weisbach equation was adjusted as a function of the pressure head by a power-law model. The possibility of using a mean diameter in the Darcy–Weisbach equation was also analyzed. Experimental investigation indicated that the friction factor in the Darcy–Weisbach equation can be accurately described using a power-law model, like the Blasius equation, but characterized by a coefficient a=0.3442 for the Turbo Tape and a=0.3225 for the Silver Tape. The obtained values of a are larger than those generally used and available in the literature. The influence of the operating pressure on the pipe diameter can be neglected for the purpose of calculating the head loss. The two approaches, considering the variation of the diameter with the pressure head and considering an optimum average diameter for the calculation of head loss by the Darcy–Weisbach equation, produce similar results, allowing accurate prediction of head loss. Evaluating the proposed mathematical models, 95% of predictions presented relative errors of head loss smaller than 5%. For the Turbo Tape, the optimum diameter for the purpose of calculating the head loss is 16.01 mm, which is very close to the value indicated by its manufacturer (15.9 mm). For the Silver Drip, the optimum diameter is 15.71 mm, while the manufacturer gives a value of 16.22 mm, which produces considerable error in the calculation of head loss.
27
Woltering, Lennart, Dov Pasternak, and Jupiter Ndjeunga. "The African market garden: The development of a low-pressure drip irrigation system for smallholders in the sudano sahel." Irrigation and Drainage 60, no. 5 (January 28, 2011): 613–21. http://dx.doi.org/10.1002/ird.610.
Full text
28
PÉREZ ORTOLÁ, M., and J. W. KNOX. "WATER RELATIONS AND IRRIGATION REQUIREMENTS OF ONION (ALLIUM CEPA L.): A REVIEW OF YIELD AND QUALITY IMPACTS." Experimental Agriculture 51, no. 2 (November 5, 2014): 210–31. http://dx.doi.org/10.1017/s0014479714000234.
Full textAbstract:
SUMMARYThe results of international research on the water relations and irrigation needs of onions have been synthesised in an attempt to link fundamental studies on crop physiology to irrigation practices, and consequent impacts on crop yield, quality and storage. Following a brief introduction on its origins and centres of production, a synthesis of research on crop development including plant water relations, crop water requirements, yield response to water, irrigation systems and scheduling are presented. Most of the evidence stems from research conducted in arid and semi-arid regions, notably the USA, India, Spain and Turkey. The findings confirm that onion seasonal water requirements are highly variable depending on agroclimate, location and season, as are the crop coefficients (Kc) which range from 0.4 to 0.7 (initial stage), 0.85 to 1.05 (middle development) and 0.6 to 0.75 (final stage). Seasonal irrigation needs are reported to vary from 225 to 1040 mm to produce between 10 and 77 t ha−1. The most sensitive stages for water stress are at emergence, transplanting and bulb formation. Final crop quality can also be affected by water excess. Water stress at specific stages can negatively impact on quality leading to reduced size and multi-centred bulbs. In recent years, pressure on water resources, retailer demands for quality assurance and rising production costs have meant that onion irrigation has switched from traditional low efficiency (furrow) methods to more efficient advanced (sprinkler and drip) technologies. For scheduling, optimal soil water potential thresholds for triggering irrigation were found to be between −17 and −27 kPa for drip and furrow irrigation. Research is underway to maximise water use efficiency in onions, but the deficit irrigation regimes being tested under experimental conditions have yet to be adopted commercially.
29
Piromchai, Patorn, Charoiboon Puvatanond, Virat Kirtsreesakul, Saisawat Chaiyasate, and Sanguansak Thanaviratananich. "Effectiveness of nasal irrigation devices: a Thai multicentre survey." PeerJ 7 (May 27, 2019): e7000. http://dx.doi.org/10.7717/peerj.7000.
Full textAbstract:
Background Nasal irrigation is widely used as an adjunctive treatment for nasal diseases. There is little evidence regarding the efficacy of the devices used in this procedure. The objective of this survey was to evaluate the effectiveness of nasal irrigation devices based on the experiences of patients and physicians. Methods We conducted a multicentre survey study between November 2017 and October 2018. Physician and patient questionnaires were developed based on the available literature and expert opinion. The physician questionnaire was submitted to the Otolaryngology residents and staff of each centre and their network. The physicians were also asked to distribute the patient questionnaire to their patients. Results Information regarding 331 devices used by the patients was collected. The mean age of the patients was 45.46 ± 17.19 years (from 5 to 81). Roughly half were male, and half were female (48.6%: 51.4%). Among the high-pressure devices, we found that the high-pressure large-volume nasal irrigation devices yielded significantly higher symptom scores in seven of 12 domains (p < 0.05). Among the large-volume devices, we found that the large-volume high-pressure nasal irrigation devices received significantly higher symptom scores in 4 of 12 domains (p < 0.05). However, a higher proportion of patients using the large-volume high-pressure devices had retained fluid in the sinuses compared to those using large-volume low-pressure devices (p < 0.001). Conclusions This survey supports the regular use of nasal irrigation, particularly with large-volume high-pressure devices, as an effective treatment for nasal disease. It may be effective at clearing nasal secretion, improve nasal congestion, decrease post-nasal drip, improve sinus pain or headache, improve taste and smell, and improve sleep quality. It could be used by patients with good compliance and minimal side effects.
30
Ajaz, Ali, Sumon Datta, and Scott Stoodley. "High Plains Aquifer–State of Affairs of Irrigated Agriculture and Role of Irrigation in the Sustainability Paradigm." Sustainability 12, no. 9 (May 4, 2020): 3714. http://dx.doi.org/10.3390/su12093714.
Full textAbstract:
Groundwater depletion is a serious issue in the southern and central parts of the High Plains Aquifer (HPA), USA. A considerable imbalance exists between the recharge process and groundwater extractions in these areas, which threatens the long-term sustainability of the aquifer. Irrigated agriculture has a major share in the economy, and it requires high pumping rates in regions vulnerable to large groundwater level declines. A literature review has been conducted to understand the state of affairs of irrigated agriculture in the HPA, along with the dynamics of groundwater decline and recharge using statistical and remote-sensing based datasets. Also, three irrigation management and technology-based approaches have been discussed from the perspective of sustainability. The southern and central parts of the HPA consist mostly of non-renewable groundwater formations, and the natural water storage is prone to exhaustion. Moreover, the aforementioned regions have comparatively higher crop water requirement due to the climate, and irrigating crops in these regions puts stringent pressure on the aquifer. The upper threshold of irrigation application efficiency (IAE) is high in the HPA, and could reach up to 95%; however, considerable room for improvement in irrigation water management exists. In general, the practices of irrigation scheduling used in the HPA are conventional and a small proportion of growers use modern methods to decide about irrigation timing. Among numerous ways to promote sustainable groundwater use in the HPA, deficit irrigation, use of soil moisture sensors, and subsurface drip irrigation can be considered as potential ways to attain higher lifespans in susceptible parts of the aquifer.
31
Silva, Cláudio Ricardo da, Marcos Vinícius Folegatti, Tonny José Araújo da Silva, José Alves Júnior, Claudinei Fonseca Souza, and Rafael Vasconcelos Ribeiro. "Water relations and photosynthesis as criteria for adequate irrigation management in 'Tahiti' lime trees." Scientia Agricola 62, no. 5 (October 2005): 415–22. http://dx.doi.org/10.1590/s0103-90162005000500001.
Full textAbstract:
Irrigation scheduling based on soil moisture status is one of the most useful methods because of its practicality and low cost. The effects of available soil water depletion on evapotranspiration (ETc), transpiration (E), leaf water potential at predawn (psiP) and midday (psiM), stomatal conductance (gs) and net CO2 assimilation (A) in lime 'Tahiti' trees (Citrus latifolia) were evaluated to improve irrigation schedule and minimize water use without causing water stress. The trees were spaced 7 <FONT FACE=Symbol>´</FONT> 4 m and drip-irrigated by four drippers with the available soil water content (AWC) depleted by suspension of irrigation (40 days). Leaf water potential was measured on a pressure chamber (psiP and psiM) and leaf gas exchange was measured by infrared gas analyzer (E, gs and A). Evapotranspiration was determined with the aid of weighing lysimeter. Water soil content and potential (psiS) were monitored with TDR probes and tensiometers, respectively, installed at 0.3, 0.6 and 0.9 m depths. Meteorological variables were monitored with an automatic weather station in the experimental area. The threshold AWC level for the onset of ETc decline was 43%, and 60% for gs, A, E and Y P. Also, psiP was more sensitive to AWC than psiM, and is therefore a better tool for irrigation. When AWC was around 60%, values of psiP and psis were -0.62 MPa and -48.8 kPa, respectively.
32
Leib, Brian, Wesley Wright, Tim Grant, Amir Haghverdi, Duncan Muchoki, Phue Vanchiasong, Muzi Zheng, David Butler, and Annette Wszelaki. "Rainwater Harvesting with Solar and Gravity Powered Irrigation for High Tunnels." Applied Engineering in Agriculture 36, no. 4 (2020): 489–98. http://dx.doi.org/10.13031/aea.13969.
Full textAbstract:
HIGHLIGHTS Captured rainwater supplied nearly all the irrigation required for high tunnels in Tennessee. Solar pumping and/or gravity flow adequately supplied the pressure required for irrigation in high tunnels. Rainwater harvesting costs need to be reduced in order to be more competitive with alternate water sources. Abstract . High tunnels use clear plastic film over a large metal frame to trap solar radiation as heat in order to extend the crop growing season and reduce environmental stress. High tunnels differ from high tech greenhouses in that they use the natural soil as the growing media and use natural ventilation without fans or heaters to control the growing environment. High tunnels can provide some of the benefits of greenhouses at a much lower cost. However, the protective cover cuts-off rain water to the crop and significantly modifies the crop-water use environment. In order to reduce reliance on external sources of water, The University of Tennessee–Biosystems Engineering and Plant Science Departments implemented three types of rainwater harvesting (RWH) for high tunnels that did not require an external source of power for irrigation: gravity flow, solar battery-powered pumping, and solar transfer pumping. RWH by gravity-flow stored water captured off the high tunnels at a high enough elevation to deliver water for irrigation at very low pressure while solar battery-powered pumping delivered pressurized water directly to the irrigation system. Solar transfer pumping moved harvested rainwater to a higher elevation tank that used gravity flow to irrigate at intermediate pressures. These RWH systems were designed to store 64 mm of rainfall from the high tunnel cover (6400 L per 100 m2 of footprint area) and were able to provide 75% to 100% of the spring crop and 90% to 100% of the fall crop irrigation based on 16 experiments over six years. The RWH systems were ranked in order of increasing cost, maintenance, and complexity as follows: 1) gravity flow, 2) solar transfer pumping, and 3) solar battery-powered pumping. However, all RWH systems had high initial cost when compared to well and municipal water supplies, $12,750 to $15,950 for two 9.2- × 29-m high tunnels. Significantly lower cost rain gutters and water storage were identified but not yet tested for RWH in high tunnels. Keywords: Drip irrigation, Evapotranspiration, Gravity irrigation, Greenhouses, High tunnels, Microirrigation, Rainwater harvesting, Solar pumping.
33
Gaspar Martins Leite de Melo, Verônica, Leonardo Leite de Melo, José Antônio Frizzone, Antônio Pires de Camargo, and Patricia Angélica Alves Marques. "PERDA DE CARGA EM FITAS GOTEJADORAS COM EMISSORES MOLDADOS." IRRIGA 1, no. 1 (October 30, 2019): 86–93. http://dx.doi.org/10.15809/irriga.2019v1n1p86-93.
Full textAbstract:
PERDA DE CARGA EM FITAS GOTEJADORAS COM EMISSORES MOLDADOS
VERÔNICA GASPAR MARTINS LEITE DE MELO1; LEONARDO LEITE DE MELO2; JOSÉ ANTÔNIO FRIZZONE3; antônio pires de camargo4 E patricia algélica alves marques5
1 Departamento de Engenharia de Sistemas Agrícola, ESALQ/USP, Av. Pádias, 11, São Dimas, CEP13418-900, Piracicaba, SP, Brasil, e-mail: veronica.martins@usp.br
2 Departamento de Engenharia de Sistemas Agrícola, ESALQ/USP, Av. Pádias, 11, São Dimas, CEP13418-900, Piracicaba, SP, Brasil, e-mail: leoleitemelo@usp.br
3 Departamento de Engenharia de Sistemas Agrícola, ESALQ/USP, Av. Pádias, 11, São Dimas, CEP13418-900, Piracicaba, SP, Brasil, e-mail: frizzone@usp.br
4 Faculdade de Engenharia Agrícola – UNICAMP, Av. Cândido Rondon, 501, Cidade Universitária, CEP 13083 - 875, Campinas, SP, e-mail: antonio.camargo@feagri.unicamp.br
5 Departamento de Engenharia de Sistemas Agrícola, ESALQ/USP, Av. Pádias, 11, São Dimas, CEP13418-900, Piracicaba, SP, Brasil, e-mail: paamarques@usp.br
1 RESUMO
Embora as fitas gotejadoras sejam de baixo custo, é importante que esse material seja avaliado hidraulicamente para prover informações técnicas. O objetivo deste trabalho foi analisar a perda contínua de carga e o fator de atrito em uma fita gotejadora com emissor moldado em seu interior. O experimento foi conduzido no laboratório de irrigação da ESALQ/USP. Utilizou-se a fita gotejadora Rain-Tape® fabricada pela Rain Bird®, espessura de parede de 225 µm e emissores tipo labirinto, espaçados de 0,30 m, vazão nominal de 1 L h-1 e pressão de serviço de 55 kPa. A equação de perda de carga para regime de escoamento turbulento liso em função da vazão e da carga de pressão na entrada da fita apresenta boa habilidade para estimar a perda de carga em fitas gotejadoras com emissores moldados, sendo que 95% das estimativas apresentaram erro relativo de até 6,71%. A equação de Darcy-Weisbach pode ser utilizada para o cálculo da perda de carga desde que o diâmetro seja substituído por uma função da pressão de entrada. Para o cálculo da perda de carga, utilizando a equação de Darcy-Weisbach, o fator de atrito calculado pela equação de Blasius deve considerar um coeficiente a = 0,3408.
Palavras-chave: irrigação por gotejamento, perda de carga por atrito, fator de atrito
MELO, V. G. M. L. de; MELO, L. M. de; FRIZZONE, J. A.; CAMARGO, A. P. de; MARQUES, P. A. A.
HEAD LOSS IN DRIP TAPES WITH MOLDED EMITTERS
2 ABSTRACT
Although drip tapes are low-cost equipment, proper hydraulic evaluation is important to provide information required for irrigation system design. The aim of this study was to analyze the friction head loss and the friction factor in drip tapes with molded emitters, that are employed in drip irrigation systems. Experiments evaluated the drip tape model Rain-Tape®, manufactured by Rain Bird, 225-µm wall thickness, labyrinth-type emitters, 0.30-m emitters spacing, 1 L h-1 nominal discharge and operating pressure of 55 kPa. The following conclusions were obtained: (a) the equation of head loss for smooth turbulent flow as a function of flow rate and pressure head at the pipe inlet provided good predictions of head loss in drip tapes with molded emitters, since 95% of predictions presented relative errors less than 6.71%; (b) the Darcy-Weisbach equation may be used for calculating head loss, but the pipe diameter must be replaced by a function considering the lateral inlet pressure; (c) for calculating head loss of the Rain-Tape using the Darcy-Weisbach equation, the friction factor obtained by the Blasius equation should use the coefficient a = 0.3408.
Keywords: drip irrigation, frictional head loss, friction coefficient
34
Mosca, Marcos Antonio, Roberto Testezlaf, and Eder Pereira Gomes. "DESENVOLVIMENTO DE EMISSORES ALTERNATIVOS PARA IRRIGAÇÃO SUBSUPERFICIAL DE BAIXA PRESSÃO." IRRIGA 10, no. 3 (August 5, 2005): 249–62. http://dx.doi.org/10.15809/irriga.2005v10n3p249-262.
Full textAbstract:
DESENVOLVIMENTO DE EMISSORES ALTERNATIVOS PARA IRRIGAÇÃO SUBSUPERFICIAL DE BAIXA PRESSÃO Marcos Antonio Mosca; Roberto Testezlaf; Eder Pereira GomesFaculdade de Engenharia Agrícola, Universidade Estadual de Campinas, Campinas, SP, marcos.mosca@agr.unicamp.br 1 RESUMO A busca pela minimização da quantidade de água aplicada na agricultura pela irrigação, vem intensificando pesquisas que visam aumentar o acesso de tecnologias de irrigação mais eficientes aos agricultores, e, conseqüentemente, incentivando o uso de métodos de aplicação localizada. Com o objetivo de contribuir com informações que levem ao desenvolvimento de um sistema alternativo de irrigação por gotejamento subsuperficial avaliaram-se dois tipos de emissores desenvolvidos para operar pela ação de baixas pressões de serviço e complementarmente pelas forças matriciais do solo. Os modelos de emissores foram ensaiados em laboratório para determinação da curva característica e do perfil de redistribuição de água no solo. Os ensaios foram realizados com os emissores enterrados a 15 cm (1º modelo) e 14 cm (2º modelo) de profundidade e submetidos às pressões de 10 e 30 kPa. O regime de escoamento apresentado por ambos os modelos foi laminar, sendo que os bulbos molhados apresentaram expansões horizontais maior que as verticais, demonstrando a participação significativa das forças matriciais no processo de redistribuição de água no solo. Os emissores desenvolvidos para trabalhar subsuperficialmente e a baixa pressão demonstraram ter potencial para se tornar uma solução alternativa e com economia de água, necessitando, porém, de maiores avaliações em campo, para se tornar uma real possibilidade ao agricultor. UNITERMOS: Irrigação localizada, redistribuição de água, fluxo insaturado. Mosca, M. A.; Testezlaf, R.; Gomes, E. P. DEVELOPMENT OF ALTERNATIVE EMITTERS FOR LOW PRESSURE SUBSURFACE IRRIGATION 2 ABSTRACT Due to the need of minimizing irrigation water use, there has been an increase in research aiming to facilitate the producer’s access to efficient irrigation technologies, and therefore, stimulating the use of localized application methods. In order to contributing with information which would help develop alternative subsurface drip irrigation system, two types of emitters were developed to work under low operating pressure and also under potential soil matrix forces around the emitter. The emitters were evaluated in laboratory conditions to determine its hydraulic characteristic equations and the soil water redistribution. The emitters were buried at the depths of 15 cm (1st model) and 14 cm (2nd model) and submitted to operating pressures of 10 and 30 kPa. Both emitters had a laminar flow, and create wet bulbs, which presented horizontal expansion bigger than the vertical one. The results demonstrated that soil matrix forces participated significantly in the water redistribution process. The emitters that were developed to operate sub superficially at low pressure may become an alternate solution with water economy; however, further field evaluations still have to de carried out. KEYWORDS: Localized irrigation, soil water redistribution, unsaturated flow.
35
Robles Rovelo, Cruz Octavio, Nery Zapata Ruiz, Javier Burguete Tolosa, Jesús Ramiro Félix Félix, and Borja Latorre. "Characterization and Simulation of a Low-Pressure Rotator Spray Plate Sprinkler Used in Center Pivot Irrigation Systems." Water 11, no. 8 (August 14, 2019): 1684. http://dx.doi.org/10.3390/w11081684.
Full textAbstract:
Spray sprinklers enable to operate at low pressures (<103 kPa) in self-propelled irrigation machines. A number of experiments were performed to characterize the water distribution pattern of an isolated rotator spray plate sprinkler operating at very low pressure under different experimental conditions. The experiments were performed under two pressures (69 kPa and 103 kPa) and in calm and windy conditions. The energy losses due to the impact of the out-going jet with the sprinkler plate were measured using an optical technique. The adequacy to reproduce the measured water distribution pattern under calm conditions of two drop size distribution models was evaluated. A ballistic model was used to simulate the water distribution pattern under wind conditions evaluating three different drag models: (1) considering solid spherical drops; (2) a conventional model based on wind velocity and direction distortion pattern, and (3) a new drag coefficient model independent of wind speed. The energy losses measured with the optical method range from 20% to 60% from higher to lower nozzle sizes, respectively, for both evaluated working pressures analyzing over 16,500 droplets. For the drop size distribution selected, Weibull accurately reproduced the water application with a maximum root mean square error (RMSE) of 19%. Up to 28% of the RMSE could be decreased using the wind-independent drag coefficient model with respect to the conventional model; the difference with respect to the spherical model was 4%.
36
Souza, Rodrigo Otávio Rodrigues de Melo, Gerardo Felipe Espinoza Pérez, and Tarlei Arriel Botrel. "IRRIGAÇÃO LOCALIZADA POR GRAVIDADE COM MICROTUBOS." IRRIGA 11, no. 2 (June 18, 2006): 266–79. http://dx.doi.org/10.15809/irriga.2006v11n2p266-279.
Full textAbstract:
IRRIGAÇÃO LOCALIZADA POR GRAVIDADE COM MICROTUBOS Rodrigo Otávio Rodrigues de Melo Souza; Gerardo Felipe Espinoza Pérez; Tarlei Arriel BotrelInstituto Centro Tecnológico de Ensino – CENTEC, Fortaleza, CE, rmelosouza@hotmail.com 1 RESUMO Os objetivos deste trabalho foram: dimensionar, implantar e avaliar um sistema de irrigação com microtubos por gravidade; e apresentar o custo do sistema com microtubos comparando-o com o custo do “kit” para irrigação localizada por gravidade, disponível no mercado. O experimento foi dividido em duas etapas, sendo que a primeira consistiu no dimensionamento, elaboração, montagem e avaliação do sistema de irrigação. A segunda etapa consistiu na implantação da cultura da alface em três canteiros, onde em dois canteiros a água foi fornecida por uma caixa d’água elevada a uma altura de1 m e distribuída para as alfaces através dos microtubos. No outro canteiro, a irrigação foi realizada através de um regador. Conforme os resultados observados o sistema obteve ótimo desempenho. Além de aplicar água com 97% de uniformidade de distribuição, também ficou provado que o microtubo foi fabricado com qualidade e uniformidade. O custo total do sistema para a irrigação de 16 canteiros ficou em R$ 466,77. A proposta de utilização do sistema de irrigação localizada com microtubos por gravidade demonstrou ser uma alternativa viável, tanto tecnicamente quanto economicamente, para os pequenos produtores. UNITERMOS: Irrigação por gotejamento, microtubos, baixa pressão SOUZA, R.O.R. DE M.; PÉREZ, G.F.E.; BOTREL, T.A. GRAVITY TRICKLE IRRIGATION WITH MICROTUBES 2 ABSTRACT The objectives of this study were to design, implant and evaluate a gravity irrigation system with micro tubes; and to show the cost of the system with micro tubes compared to the cost of the “kit” for gravity drip irrigation commercialized by irrigation companies. The experiment was divided into two phases: the first one consisted of the design, elaboration, assembly and evaluation of the irrigation system, whereas the second one consisted of the implantation of a lettuce culture in three flowerbeds. The water was provided by a1 mhigh water reservoir and distributed to the lettuce culture through micro tubes in two of the flowerbeds. In the other one, the irrigation occurred through a watering can. According to the results, the system achieved a great performance. Besides applying water with 97% distribution uniformity, it has also been proved that the micro tube manufacturing had quality and uniformity. The total cost of the irrigation system implementation in 16 flowerbeds was US$ 190.51. The use of gravity trickle irrigation system with micro tubes turned out to be a possible technical and economic option for small farmers. KEYWORDS: drip irrigation, low pressure, microtubes
37
Popov, V. M., and M. M. Targoniy. "SUBSTANTIATION OF ENERGY EFFICIENT WATER SUPPLY IN CLOSED IRRIGATION SYSTEMS." Міжвідомчий тематичний науковий збірник "Меліорація і водне господарство", no. 2 (December 12, 2019): 243–49. http://dx.doi.org/10.31073/mivg201902-192.
Full textAbstract:
Relevance of research. The research is aimed at improving the energy efficiency of automated water supply in irrigation systems. The purpose and objectives of research. The purpose of the research is to reduce the specific energy consumption for pumping water by pumping stations (PS) in closed irrigation systems (CIS). The task is to substantiate the efficiency of the method of automated control of water supply to the CIS when regulating the pressure at the outlet of the pumping station, which is set by the sum of hydraulic losses in the network from the pumping station to irrigation equipment (IE), static and free pressure at the dictating hydrant of CIS. The logical-mathematical model and technological conditions of energy-efficient water supply management "when it need" in CIS are given. The technical requirements for pumping units (PU) and auxiliary technological equipment of PS are presented in the application of automated water supply control with the use of frequency converters (FC).Research methods: experimental, mathematical modeling. Substantiation of the feasibility of introduction of automated electric drive with FC, as one of the measures of energy efficiency improvement, was carried out based on the results of energy audits of the PU and the CIS with the use of measuring equipment on the request of inter-district water management administration. The object of the energy audit is the CIS, which has been in operation since 1979. The PS is equipped with four PU with centrifugal section pumps 150-CVE-350-23/3 (D = 350 mm) and drive motors of the brand MAF315SK-4 with a rated power of 132 kW. During the period of operation the reconstruction and restoration of the CIS took place. “Dnepr” sprinkling machines have been replaced by modern low pressure SM and drip irrigation systems. With the replacement of irrigation equipment, asbestos-cement field pipelines with diameters D = 400 mm were replaced too with the plastic ones of D = 200 mm. The configuration, hydraulic characteristics of the CIS and modes of operation of the PU were changed. The efficiency of the pumps 150-CVE-350-23/3 decreased by 10-15% during the long-term operation of the PU. Research results. For energy efficient water supply management, it is proposed to: replace four worn pumps 150-CVE-350-23/3 with three pumps of domestic production ЦН400-105б; implement a system of automated water supply management at the CIS with the use of FC. Conclusions. The effectiveness of the application of a new method of water supply control in the CIS, which provides for automatic control of the pressure at the outlet of the PS, is given by the sum of hydraulic losses in the network from the PS to the IE, static and free pressure at the dictating inlet of the operating IE, using the proven FC. Introduction of automated electric drive with the FC on the PS-4 of the “Repin” CIS enables to reduce the daily power consumption from 12% to 25%.
38
Ngouajio, Mathieu, Rafael Auras, R. Thomas Fernandez, Maria Rubino, James W. Counts, and Thitisilp Kijchavengkul. "Field Performance of Aliphatic-aromatic Copolyester Biodegradable Mulch Films in a Fresh Market Tomato Production System." HortTechnology 18, no. 4 (January 2008): 605–10. http://dx.doi.org/10.21273/horttech.18.4.605.
Full textAbstract:
Removal and disposal of polyethylene mulch in vegetable production represents a high economic and environmental cost to society. This study was conducted in 2006 and 2007 at Michigan State University to test the field performance of new biodegradable mulches using ‘Mountain Fresh Plus’ tomato (Solanum lycopersicum) as a model crop. Treatments included two biodegradable mulches (black and white), each with two thicknesses (35 and 25 μm). A conventional low-density polyethylene (LDPE) mulch of 25 μm was included as a control (a mulch commonly used by vegetable growers). Data loggers were installed 2 cm into the soil under the various mulches to record soil temperature. The experiment used a randomized complete block design with four replications. The mulches were used on a raised bed, drip irrigation system. Mulch degradation, soil temperature, tomato growth, weed density, and biomass were assessed during the seasons. Tomatoes were harvested at maturity and were fruit graded according to market specifications. Results indicate that soil temperature under the biodegradable mulches was greater than that under the LPDE mulch during the first week. Starting the second week, soil temperature dropped gradually under all the biodegradable mulches. The drop in temperature was greatest with the white mulch. Due to premature breakdown of the white mulches, weed pressure was high, resulting in smaller plants with low yield in 2007. Tomato growth, yield, and fruit quality from the black mulch was equivalent to that in the LDPE mulch. Future studies will optimize biodegradability of the mulches and test mechanical laying of the black mulch under commercial production.
39
Feng, Ji, Weinan Wang, and Haisheng Liu. "Study on Fluid Movement Characteristics inside the Emitter Flow Path of Drip Irrigation System Using the Yellow River Water." Sustainability 12, no. 4 (February 12, 2020): 1319. http://dx.doi.org/10.3390/su12041319.
Full textAbstract:
Vigorously developing efficient water-saving agricultural technologies using the Yellow River Water is an important way to achieve sustainable use of water resources. In order to clarify the fluid movement characteristics inside the flow path of the emitter under complicated water quality conditions in a drip irrigation system using the Yellow River Water, the optimal simulation turbulence model for the flow field in the flow path of the emitter was determined by comparing the macroscopic hydraulic characteristics with the microscopic fluid motion characteristics of the fluid in the emitter. On this basis, the two-phase flow model was used to calculate and analyze the characteristics of water flow movement and particle transport in the emitter. The results show that the RNG (Re- normalization group) k-ε turbulence model was the most suitable for the simulation of the flow field in the emitter, considering the macroscopic hydraulic performance and microscopic anti-clogging ability of the emitter synthetically, and both the comprehensive calculation accuracy and the calculation efficiency. The pressure showed a step-like uniform decrease along the direction of water flow. The fluid flow showed the regional movement characteristics of the mainstream and non-mainstream regions. The energy dissipation mainly occurred at the sudden change sites of the flow path structure. The particle phase velocity was slightly lower than that of the water phase. The velocity at the near-wall surface was relatively lower than that at the center, and the velocity distribution along the depth direction of the flow path was relatively uneven. The sediment was mainly deposited in the first half of the flow path. This study can provide a theoretical basis for solving the emitter clogging in the drip irrigation systems applying water from the Yellow River.
40
Solé-Torres, Carles, Freddie R. Lamm, Miquel Duran-Ros, Gerard Arbat, Francisco Ramírez de Cartagena, and Jaume Puig-Bargués. "Assessment of Microirrigation Field Distribution Uniformity Procedures for Pressure-Compensating Emitters under Potential Clogging Conditions." Transactions of the ASABE 64, no. 3 (2021): 1063–71. http://dx.doi.org/10.13031/trans.14486.
Full textAbstract:
HighlightsDistribution uniformity of the lower quartile (DUlq) was assessed in three microirrigation subunits with three procedures that used different locations and different numbers of sampled emitters.Using reclaimed effluent as the water source, performance was periodically measured for a total duration of 1000 h.Emitter clogging and the locations of sampled emitters greatly affected DUlq.None of the procedures accurately assessed DUlq if more than 4% of the emitters were fully clogged.Abstract. Proper water distribution uniformity is important for successful use of microirrigation systems. Consequently, consistent system monitoring and periodic distribution uniformity assessments can help determine the performance of a microirrigation system and identify possible problems that should be corrected. When using irrigation water with a greater clogging risk, such as reclaimed effluent, emitter clogging can seriously affect distribution uniformity. In this study, distribution uniformity was measured at three times (0 h, 500 h, and 1000 h of operation) in a microirrigation system that used reclaimed effluent. Emitter discharge values were obtained for each emitter in the system (three subunits consisting of four driplines each with 226 pressure-compensating emitters on each dripline), and the distribution uniformity of the low quartile (DUlq) was calculated for each subunit. These comprehensive DUlq values were compared with those calculated by three estimation procedures developed by Merriam and Keller, Burt, and Juana et al., which use different sampling locations and different numbers of sampling points. Results showed strong influence of emitter clogging and the location of the sampled emitters on DUlq values. Using this data set, the Merriam and Keller procedure had the greatest root mean square error (RMSE = 41.8%), the Burt procedure resulted in an intermediate value (RMSE = 5.9%), and the Juana et al. procedure had the lowest (RMSE = 3.2%) when most of the completely clogged emitters (about 1% of the total) were located at the ends of the driplines. Further speculative analysis in which complete clogging was allowed to migrate to the farthest distal emitters for the Burt and Juana et al. procedures indicated that none of the procedures accurately assessed the actual complete DUlq. These results suggest that none of these procedures alone are successful at assessing system-wide distribution uniformity when substantial clogging exists. Keywords: Drip irrigation, Effluent, Emitter clogging, Flow variation, Wastewater.
41
Yıldırım, Gürol. "Discussion of “Assessment of Hydraulic Performance of Drip-Irrigation Emitters at Low Head Pressures” by Chao Zhang, Yaohu Kang, Shufang Jiang, Shuqin Wan, and Shiping Liu." Journal of Irrigation and Drainage Engineering 140, no. 3 (March 2014): 07014003. http://dx.doi.org/10.1061/(asce)ir.1943-4774.0000597.
Full text
42
Sanchez, Charles A. "Response of Lettuce to Water and Nitrogen on Sand and the Potential for Leaching of Nitrate-N." HortScience 35, no. 1 (February 2000): 73–77. http://dx.doi.org/10.21273/hortsci.35.1.73.
Full textAbstract:
The low desert region of Arizona is the major area of lettuce (Lactuca sativa L.) production in the United States during the winter. Lettuce is commonly grown on the loam, clay loam, and clay soils of the alluvial river valleys. There is some interest in moving a portion of the vegetable production onto the sandy soils of the terraces (mesa) above the alluvial river valley to partially relieve the intensive production pressure being placed on lands in the valley. Of major concern in these sandy soils is water and N management. Studies were conducted during two seasons to evaluate the response of crisphead lettuce to sprinkler irrigation and N fertilizer and to evaluate the potential for leaching of nitrate-N on a coarse-textured soil. Lettuce yields increased in response to water and N, and were maximized by 55 cm of water and 271 kg·ha–1 N in 1991–92 and 76 cm water and 270 kg·ha–1 N in 1992–93. These water and N rates exceeded those typically required on finer-textured alluvial valley soils. At N and water rates required for maximum yields, 88% and 77% of the applied N was not recovered in the aboveground portions of the plant during the 1991–92 and 1992–93 seasons, respectively. Overall, data for the amount of N fertilizer not recovered, estimates of nitrate-N leaching determined during one growing season, and analysis of soil samples collected after harvest indicate the potential for large N leaching losses on this coarse-textured soil. Alternative production methods that enhance water and N use efficiencies, such as drip irrigation and/or the use of controlled-release fertilizers, should be considered on this sandy soil.
43
Benin, Dmitry, and Vera Snezhko. "Water flow regulator for irrigation canals." E3S Web of Conferences 264 (2021): 03038. http://dx.doi.org/10.1051/e3sconf/202126403038.
Full textAbstract:
A distinctive feature of the irrigated systems of the Russian Federation is a large area of irrigated areas and a significant length of irrigation canals. With a large area of the irrigated massif on small canals, the use of electricity to regulate the throughput of network hydraulic structures is economically ineffective. Preference is given to means of hydraulic automation of water supply. Regulation of the throughput of a hydraulic structure is based on the laws of fluid flow within it. On irrigation canals in Russia, as in world practice, water-operated gates are widely used. One of the disadvantages of such gates is moving metal parts and sensors, which reduce the operational reliability of structures. A new regulator of throughput is proposed, the action of which is based on the injection effect. Compression of the flow by physical elements was replaced by the circulation of surplus water supply between the outlet section of the water supply structure and the downstream. The regulator is built into the pressure drop between the high and low order channels. Regulating the throughput of the tubular water outlet automatically begins after shutting down one or more sprinklers that take water from the lower order canal. After turning the sprinklers into operation, the regulator automatically restores the original throughput. Using the theory of jet pumps, a new method has been developed for the theoretical determination of the main hydraulic characteristics of the regulator. These include the size of the nozzle and the velocities of the injection and injection streams. The derivation of theoretical dependencies was based on the classical equations of fluid mechanics; the flow within the structure was considered quasi-one-dimensional. The obtained calculated dependencies were verified using numerical and physical modeling. The data of the physical and numerical experiment were in good agreement with the theoretical dependences. Further optimization of the controller can be performed by changing its geometric parameters.
44
Coolong, Timothy. "Yellow Squash and Zucchini Cultivar Evaluation in Georgia." HortTechnology 27, no. 2 (April 2017): 296–302. http://dx.doi.org/10.21273/horttech03605-16.
Full textAbstract:
Ten yellow squash (Cucurbita pepo) and nine zucchini (C. pepo) cultivars were evaluated in southwest Georgia during spring and fall growing seasons in 2014 and 2015. Plants were grown using plastic mulch and drip irrigation following standard production practices for squash in Georgia. Plants were harvested 10 to 13 times during each study season. Fruit were graded into fancy, medium, and culls. Virus pressure was low during the trials. For yellow squash yields, there were significant cultivar by season interactions; however, Solstice, a straightneck yellow squash, and Gentry, a crookneck cultivar, were consistently among the highest yielding yellow types. Despite having no documented virus resistance, ‘Gentry’ performed well during the fall season. However, ‘Precious II’, a yellow straightneck cultivar with the presence of the precocious yellow gene, experienced high cull rates in the fall due to virus effects on the fruit. There was a year by season by cultivar interaction for zucchini yield. Despite this interaction, ‘Respect’ was ranked among the highest yielding cultivars in all four seasons of the trial. Differences were also observed between seasons for yellow and zucchini squash, with fall yields generally being lower than those in the spring. The results of this study suggest significant differences in the adaptability of squash cultivars for spring and fall production in Georgia. In addition, virus resistance, while important, should not be the exclusive factor for determining cultivars for fall-planted squash in Georgia.
45
Archana, HA, N. Asoka Raja, R. Mahesh, and R. Kalpana. "Effect of Low Cost Drip Tape Irrigation System on Yield and Economics of Sweet Corn." Bangladesh Agronomy Journal 19, no. 2 (March 10, 2017): 71–77. http://dx.doi.org/10.3329/baj.v19i2.31855.
Full textAbstract:
A study was conducted to determine the effect of low cost drip tape irrigation system on yield and economics of sweet corn in comparison to conventional inline drip irrigation and surface irrigation systems during 2013-14 at Coimbatore, India. The treatment comprises of two drip irrigation systems with three irrigation levels viz., 75, 100 and 125% of pan evaporation (PE) from Class A Pan evaporimeter. Plant height, fresh cob length, girth, number of kernels per cob and single fresh cob weight and yield were higher at 125% PE in conventional in line drip irrigation system and it was statistically at par with drip irrigation at 125% PE in low cost drip tape irrigation system. Water saving was 36, 49 and 62% at 125, 100 and 75% PE, respectively under conventional in line drip irrigation system and drip tape irrigation system as against the surface irrigation. The cost of low cost drip tape system was 68% lower than the conventional inline drip system. The results of the research indicated that based on net income, B:C ratio and GM/TMV ratio, adoption of low cost drip tape irrigation system at 125% PE was found to be best for small and marginal farmers with substantial yield and income compared to conventional inline drip system.Bangladesh Agron. J. 2016 19(2): 71-77
46
Bagarello, V., V. Ferro, G. Provenzano, and D. Pumo. "Evaluating Pressure Losses in Drip-Irrigation Lines." Journal of Irrigation and Drainage Engineering 123, no. 1 (January 1997): 1–7. http://dx.doi.org/10.1061/(asce)0733-9437(1997)123:1(1).
Full text
47
Lilley, Jason M., and Elsa S. Sánchez. "The Potential of Strip Tillage and Rowcovers for Organic Cucurbit Production." HortTechnology 26, no. 5 (October 2016): 628–36. http://dx.doi.org/10.21273/horttech03405-16.
Full textAbstract:
Plasticulture systems, the use of polyethylene mulch on raised beds with drip irrigation, are commonly used for the production of many cucurbit (Cucurbitaceae) crops. Although the use of plasticulture systems has many benefits, disadvantages include plastic disposal issues and costs and the intensive tillage required for installation. Strip tillage systems have been shown to decrease soil erosion, increase soil moisture retention, and increase soil microbial communities. Spunbonded polyethylene rowcover use has been shown to decrease early season striped cucumber beetle (Acalymma vittatum) and spotted cucumber beetle (Diabrotica undecimpunctata) populations and the incidence of bacterial wilt (Erwinia tracheiphila) while increasing yields. Plasticulture and strip tillage systems were compared with and without rowcovers at The Pennsylvania State University’s Russell E. Larson Research and Education Center in Rock Springs, PA. Two separate organically managed experiments were conducted, one being on ‘Lioness’ summer squash (SS; Cucurbita pepo), the other on ‘Athena’ muskmelon (MM; Cucumis melo). Both two-season experiments occurred during the 2013 and 2014 growing seasons. Yields, soil nitrate levels, soil and air temperatures, striped cucumber beetle populations, and incidence of bacterial wilt were measured. Plants grown in the strip tillage system generally had lower yields than in the plasticulture system in both years. Yield reductions observed in the strip tillage system in both years of the muskmelon experiment and in the first year of the summer squash experiment were beyond acceptable levels. The need for specialized tillage equipment, delayed planting, and high weed pressure were all obstacles to the successful use of strip tillage in these experiments. Rowcovers resulted in larger plants; however, yields were comparable to not using rowcovers within the strip tillage and plasticulture systems. There was low incidence of bacterial wilt in both years of the experiments despite observed striped cucumber beetle populations above the set threshold throughout all experiments.
48
Arriero, Stephanie S., Willian F. de Almeida, Vital P. da S. Paz, and Lucas F. Damasceno. "Yield of eggplant using low quality water and pulse drip irrigation." Revista Brasileira de Engenharia Agrícola e Ambiental 24, no. 12 (December 2020): 822–26. http://dx.doi.org/10.1590/1807-1929/agriambi.v24n12p822-826.
Full textAbstract:
ABSTRACT The use of saline water and wastewater in agriculture has been increasingly considered, and this is due to the increase in awareness about the conservation of natural resources and population growth, implying a greater demand for food. Drip irrigation already has many benefits and, with the splitting of the depths to be applied, results in pulse drip irrigation, which further favors the plant by providing more constant moisture in the soil. The objective of this study was to evaluate the effects of the application of wastewater and saline water by pulse drip irrigation on eggplant yield and water use efficiency. The experimental design was randomized blocks in 2 x 5 factorial scheme, corresponding to continuous and pulse drip irrigation and five types of water (municipal, saline (sodium chloride), saline (calcium chloride), wastewater, and a mix of saline (sodium chloride) and wastewater), with five repetitions. Water use efficiency was quantified according to the water applied and the production. Pulse drip irrigation promoted higher marketable fruit yield. The best performance of eggplant was verified when wastewater was applied via pulse drip irrigation. Wastewater via pulse drip irrigation can be used to grow eggplant for higher marketable yield and water use efficiency.
49
von Westarp, Stefanie, Sietan Chieng, and Hans Schreier. "A comparison between low-cost drip irrigation, conventional drip irrigation, and hand watering in Nepal." Agricultural Water Management 64, no. 2 (January 2004): 143–60. http://dx.doi.org/10.1016/s0378-3774(03)00206-3.
Full text
50
Blom, Theo J., and Brian D. Piott. "COMPARISON OF LOW VOLUME DRIP AND SUBIRRIGATION SYSTEMS." HortScience 25, no. 9 (September 1990): 1113e—1113. http://dx.doi.org/10.21273/hortsci.25.9.1113e.
Full textAbstract:
Low volume drip (2 l/h) was compared with 2 subirrigation ('trough' and `ebb and flo') systems for production of poinsettias and chrysanthemums in 15 cm diameter (1.6 l) `azalea' pots. Irrigation frequency as well as fertilizer rates were the same for all systems. The drip system received 280 ml per watering.Two plantings of poinsettias (fall) as well as two plantings of chrysanthemums (spring and summer) showed no differences in plant growth between the drip and the subirrigation systems. Water uptake by the medium was similar for all irrigation systems, but water and fertilizer application was 70% higher for the drip system. Nutrients, measured at 4 depths within the pot at monthly intervals, increased with time and was markedly more concentrated in the top layer, regardless of the irrigation system.