Drip / trickle irrigation Research Papers (original) (raw)

Soilless cultivation is a method that permits the achievement of high yields, good control of plant growth and development, and is currently in practice all over the world. Several irrigation systems have been developed for containerized-crops (drip-irrigation and subirrigation). Irrigation system can significantly impact the effect of irrigation water salinity on crop performance. Comparing the subirrigation and drip-irrigation systems using saline and non-saline nutrient solutions can be useful for developing optimal management strategies in semiarid regions which are characterized by the shortage of good quality water. A greenhouse experiment was carried out during the spring-summer season to determine the influence two irrigation systems (drip and subirrigation) and two nutrient solution concentrations (2.0 and 4.1 dS m À1 ) on substrate electrical conductivity (EC e ), growth, yield, fruit quality (dry matter, carbohydrates, protein, Vitamin C), yield water use efficiency (WUE y ) and tissue mineral composition of zucchini squash (Cucurbita pepo L.). At the mid and at the end of the trial, plants grown with the subirrigation system resulted in a higher EC e in the upper and lower parts of the substrate in comparison to the drip-irrigation system, especially at an EC of 4.1 dS m À1 . At an EC of 2.0 dS m À1 , zucchini yield (total and marketable) was 13% lower with the subirrigation than with the drip-irrigation systems but offered several benefits: higher fruit quality (dry matter, glucose, fructose, starch and total carbohydrates content) and WUE y . The yield reduction with www.elsevier.com/locate/agwat Agricultural Water Management 82 (2006) 99-117 subirrigation was more pronounced at an EC 4.1 dS m À1 , where the zucchini production with subirrigation was lower by 36% than with drip-irrigation. Increasing salinity from 2.0 to 4.1 dS m À1 improved fruit quality (high content of dry matter, reduced sugars, starch, total carbohydrates, and Vitamin C) in both irrigation systems. The results indicate that the choice of the irrigation system appears to be of foremost importance especially when using low quality irrigation water. Unlike subirrigation, using drip-irrigation with saline solution (4.1 dS m À1 ) would be an attractive strategy in limiting yield reduction, taking advantage of the quality effect of saline water and improving the WUE y .

- by
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- Civil Engineering, Horticulture, Water Engineering, Brackish Water

Les petites exploitations agricoles adoptent souvent des systèmes d'irrigation en goutte-àgoutte simplifiés, à faible coût, au lieu des systèmes sophistiqués promus conventionnellement. Nous étudions ici les processus d'adoption du goutte-à-goutte à travers des initiatives locales ou des programmes étatiques dans les exploitations du Gharb au Maroc. On distingue trois types d'installations : celles qui sont conformes aux normes internationales, subventionnées par l'É tat, dans les grandes exploitations ; celles qui sont réalisées à partir de l'expertise locale, plus simples, moins coûteuses, dans les petites exploitations maraîchères ; et celles qui sont réalisées à partir d'un matériel d'occasion, à faible coût et très mobiles, utilisées sur de petites parcelles dispersées. Ces deux derniers systèmes sont installés par des intermédiaires informels. Nous montrons que les dynamiques issues des initiatives locales et étatiques se croisent et se renforcent. Si ce sont les grands exploitants qui ont impulsé la diffusion du goutte-à-goutte conforme, ce sont les programmes étatiques qui ont conforté ce développement en attirant les investisseurs à travers les subventions. Ces grands exploitants sont aussi à l'origine du développement du goutte-à-goutte par des initiatives locales, en ayant permis la multiplication d'intermédiaires. Enfin, en transformant le goutte-à-goutte, les initiatives locales ont permis de déconstruire l'objet de l'innovation et ainsi de le reconstruire en l'adaptant à différents contextes, multipliant les possibilités d'adoption par le plus grand nombre.

- by Tarik Hartani and +1
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- Water, Economy, Drip / trickle irrigation, Farming

This study addressed the vegetative development, yield, and root development of coffee during cultivation in the absence and presence of drip irrigation and in different population arrangements over five years. A 6 × 2 factorial experimental scheme was used with a randomized block design and four replications. The six plantation densities were 1.60 × 0.50 m; 1.60 × 0.75 m; 1.60 × 1.00 m; 3.20 × 0.50 m; 3.20 × 0.75 m; and 3.20 × 1.00 m. These plantation densities were divided into irrigated and non-irrigated treatments. The analysis of variance of the interaction between planting density and irrigation revealed absence of synergism in changing the biometric parameters. However, the isolated analysis of the factors showed significant effects of plantation densities, with the arrangement of 1.60 × 0.50 m getting the highest values of plant height and the smallest crown diameter, over the cycles. The adoption of irrigation caused significant effects on biometric parameters, with the irrigation of coffee causing increase in plant height, crown diameter and stalk diameter. The irrigated coffee in the four cycles resulted in a higher processed coffee production, especially when coffee was grown with small row spacing. The irrigated coffee obtained the average yield of 2623 kg ha −1 , while the coffee without irrigation had an average yield of 1026 kg ha −1 . The irrigated treatments had greater root concentrations as compared to the non-irrigated treatments. In addition, the root concentration was greater in the 0-0.5-m layer when smaller row spacing was used.

Bitter gourd (Momordica charantia), a seasonal vegetable is a source of many essential nutrient and contain low energetic and anti-diabetic property. To increase the self-life, a drying operation was done by using hot air oven dryer at different thickness of fruit slice (3,6 and 9mm) and temperature (60 ,70 and 80°C). The sliced bitter gourds were treated by NaCl solution before drying and dried up to 5 per cent moisture content (MC) on dry basis (db) and grinded to powder for further experiment. The drying rate increases with increase of temperature and decrease of thickness whereas diffusion and activation energy increase with increase of temperature and thickness and they are significantly variable. The maximum value of diffusion coefficient, activation energy, ascorbic acid and the protein were found at 80°C and 9mm thickness (1.9149×10-9 (m 2 s-1), 118.77 KJ kg-mol-1 , 77.65 mg100g-1 and 5.65% (d.b.)) and minimum at 60°C and 3mm (0.0085×10-9 (m 2 s-1), 74.93 KJ kg-mol-1 , 17.65 mg 100g-1 and 3.77% (d.b.)). Losses of nutrients were non-significantly variable.

- by Giuseppe Colla
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- Horticulture, Seasonality, Water use efficiency, Drip / trickle irrigation

Final paper in irrigation system design.

The developed model 'Drip Chartist' by Ismail et al. (2006a) was verified and validated in field and by comparison to other related model "Hydrus 2D". Field validation resulted showed that the surface system without hydraulic barrier represents the real-condition by 94.99% (correlation coefficient of 0.9746) with under estimation of 0.157. While in the subsurface system with hydraulic barrier represents the realcondition by 81.96% (correlation coefficient of 0.9053) with under estimation of 0.021. Validation to Hydrus2D lead to almost coincidence in predicted values of wetting pattern. Several studies were performed using the model, like studying soil properties such as θsat, θres, Ks, and the retention and conductivity parameters of soil such as α, m, n, λps, and ϒ effect on soil moisture pattern. The effect of soil texture indicated that the heavy textured soils could be simulated faster than light texture soils, while silt texture soil was simulated in longer time compared to other texture classes, solution methods, and other properties were studied as well. In addition, some construction alternatives of the system were studied like the effect of bilateral gap, dripper line burying depth, physical barrier and the emitter discharge on the wetting pattern. The model "Drip Chartist" was proved to act like intended in predicting surface and subsurface drip wetting pattern.

- by Mohammad ElNesr
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- Modelling, Flood modelling, Model validation, Drip / trickle irrigation

Subsurface drip irrigation systems, compared to other irrigation systems, enhance delivery of water and chemicals directly into the root zone. However, in light-textured soils, certain quantities of water may percolate below the root zone due to the subsurface position of drip lines. The main objective of this paper is to evaluate three technologies to enhance a spatial distribution of water and solutes in the root zone and to limit downward leaching. The three technologies include a) a physical barrier, b) a dual-drip system with concurrent irrigation, and c) a dual-drip system with sequential irrigation. To achieve this objective, we performed computer simulations and field experiments. Numerical simulations were carried out using the HYDRUS (2D/3D) software for both bare and cultivated soils. The results indicate that the physical barrier is more efficient than dual-drip systems in enhancing the water distribution in the root zone while preventing downward leaching.

- by Mohammad ElNesr
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- Agricultural Engineering, Phytoremediation, Irrigation, Irrigation Engineering

Simulation models are useful tools for enhancing water management on farm level and optimizing water application efficiency. Focusing on water, as water is the key driver of agricultural production and the critical factor of increasing crop production. Evaluating effects of water saving to optimize water application efficiency under limited conditions to enhance sustainability an (surface drip irrigation and solid-set sprinkler) at the Experimental Farm of d profitability of crop production. HydroCalc model was evaluated under two lateral length (30, 50m) and (0, 0.02) slopes under pressurized irrigation systems Agricultural Production and Research Station, National Research Centre (NRC), El Nubaria, Egypt, (latitude 30.87N, longitude 30.17E and altitude 20 m above sea level). The results obtained declared that: The statistical indicators; the regression coefficient (R² > 0.90) and correlation coefficient confirmed the good performance of HydroCalc in simulating some hydraulic parameters of pressurized irrigation systems. The validation of measured and simulated data clarified it as efficient reliable software to design pressurized irrigation systems to increase the system performance and water application efficiency. The energy savings were (33.18; 27.33%) under slope (0%) and (34.23; 29.54%) under slope (2%) with surface drip irrigation systems when using lateral lengths (30;50m), respectively compared to the solid-set sprinkler irrigation system. It could be concluded to using drip irrigation systems with lateral length 30 m and with slope (2%) downhill for increasing the water application efficiency, decreasing the friction losses along lateral lines and this lead to saving more water head energy.

- by Samir Attia
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- Water Engineering, Drip / trickle irrigation

The aim of this study was to assess the effect of applying different irrigation levels and soil mulches on vegetative growth, yield and water use efficiency (WUE) of potato (Solanum tuberosum L.) valor cultivar. The experiment was carried out during two successive seasons of 2010/2011 and 2011/2012 under open field conditions in El-Bossily farm, Agricultural Research Center, El-Beheira Governorate, Egypt. The experimental design was split plot and consisted of three irrigation levels as main plots and three soil mulches as sub-plots with three replicates. Drip irrigation was practiced at 50, 75 and 100% of irrigation requirements (IR). The soil mulches consisted of black (PE-B) and transparent (PET) polyethylene as well as rice straw (RS). In both seasons, the application of different irrigation levels and mulch treatments affected significantly potato vegetative growth, tuber yield and nutrients content (N, P and K). The use of PE-B mulch resulted in significantly higher values of plant height, number of leaves, canopy fresh and dry weight per potato plant. Increasing IR of potato from 50% to 100% enhanced total and marketable yield. The highest WUE was obtained under PE-B mulch followed by RS and both of them were superior compared to the PET and bare soil. Regarding the interaction between irrigation and mulching treatments, the highest vegetative and tuber yield were obtained by PE-B treatment combined with 100% IR. However, the highest WUE was obtained by 75% IR combined with PE-B mulch.

- by Mohamed Abdrabbo and +1
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- Irrigation, Irrigation water use efficiency, Irrigation Engineering, Irrigation water Management

Hazen-Williams equation is used widely by irrigation systems’ designers due to its simplicity.However, Darcy-Weisbach equation is more accurate and reliable. The accuracy of the latter is due to its friction coefficient, which depends on both flow characteristics and pipe surface state. On the other hand, Hazen-Williams’ coefficient (C) depends only on pipe substance and age. A comparative analysis of both models was performed through a simple iterative model. The analysis was based on the real state design procedure of drip laterals. More accurate values of coefficient C were suggested to be used in designing drip laterals. A straightforward equation was developed to compute C depending on emitter flowrate, emitter flow exponent, and pipe diameter.The results reveal that C ranges from 132 to 138 for drip laterals, while it was proved that using C=150 is reasonable for manifolds design.

- by Mohammad ElNesr
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- Hydraulics, Friction Models, Drip / trickle irrigation, Drip Irrigation
- by Desalegn Chemeda and +1
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- Civil Engineering, Water Engineering, Pepper, Agricultural Water Management

‫السماد‬ ‫نوع‬ ‫التسميد‬ ‫معدل‬ ‫وقت‬ ‫التسميد‬ ‫النمو‬ ‫مرحلة‬ ‫المحصول‬ ‫نوع‬ ‫الرى‬ ‫مياه‬ ‫نوع‬ ‫خصائص‬ ‫األرض‬ ‫صلبة‬ ‫غازية‬ ‫الذوبان‬ ‫درجة‬ ‫مباشر‬ ‫إضافه‬ ‫ة‬ ‫للنب‬ ‫ات‬ ‫ورق‬ ‫تسميد‬ ‫ى‬ ‫السماد‬ ‫صورة‬ ‫ع‬ ‫التسميد‬ ‫يتوقف‬... more

Zucchini plants (Cucurbita pepo L. cultivar Afrodite) were grown during a summer-fall season in closed-soilless systems using a mixture peat-pumice to evaluate the effects of irrigation system (drip irrigation and subirrigation) and nutrient solution concentration (half = 1 dSÁm -1 and full = 2 dSÁm -1 ) in terms of substrate electrical conductivity (EC s ) using the dilution 1:1.5 media:water method, growth, yield, leaf mineral composition, fruit quality, and mineral solution composition. At the end of the cultural cycle, the highest EC s at the upper (0 to 7.5 cm) and lower (7.5 to 15.0 cm) layers were recorded with subirrigation using a full nutrient solution concentration. The highest plant growth, yield, and leaf macroelements concentration (nitrogen, phosphorus, and potassium) were recorded in both irrigation systems using a full-strength solution, followed by drip irrigation, and finally by subirrigation treatment using a halfstrength nutrient solution. Fruit yield, fruit mineral composition (phosphorus, potassium, calcium, and magnesium), and leaf macroelements concentration (nitrogen, phosphorus, potassium, and magnesium) were substantially reduced when the concentrations of macronutrients in the feed solution were lowered to 50% of control. Using half-nutrient solution concentration, the marketable yield reduction was more pronounced with subirrigation (58%) than with drip irrigation (42%). The variation of the macronutrient and EC in the solution during the growing cycle was less pronounced in the subirrigation than with the drip irrigation system, which represents an important aspect for the simplification of the closed-loop management of the nutrient solution.

- by Giuseppe Colla
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- Horticulture, Water Engineering, Calcium, Phosphorus

Abstract --Introduction. The Sahel zone of Africa is characterized by recurring dryness, increased soil degradation, low agriculture yields and frequent periods of famines. It is consequently necessary to introduce crops less dependent on rainfall and able to participate in food self-sufficiency. In this context, we tested improved cultivars of jujube tree in the north of Burkina Faso. Materials and methods. Five improved cultivars of jujube tree of Israeli (Ben Gurion) or Indian (Gola, Kaithali, Seb and Umran) origin were planted in a research station starting from young grafted seedlings (approximately 500 plants·ha -1 ); they were irrigated either by a traditional manual technique, or by a drip system. Fruit weight and dimension (length and width) were studied after 2 and 3 years of plantation. Results. The cultivar yields in the second and third years, irrespective of the cultivar, gave, respectively, 0.48 t·ha -1 and 3.54 t·ha -1 with an average annual production of (0.97 and 7.08) kg per plant. The cultivars Ben Gurion, Gola and Seb produced approximately 500 fruits per plant, Umran, 300 fruits per plant, and Kaithali, 200 fruits per plant. The cultivar Ben Gurion presented the highest average fruit weight (15 g) and Kaithali, the lowest (6 g). The most productive cultivars proved to be Ben Gurion and Gola which, with the cultivar Umran, gave the largest fruits. Discussion and conclusion. The yields observed for the 2-and 3-year-old plants could produce, by extrapolation, a harvest of almost 13 t·ha -1 in the ninth year. These first results obtained in an area not very favorable for agricultural production make it possible to consider the possibility of developing the jujube tree in the Sahelian zone of Africa, and could lead in the long term to a substantial income source for the local populations.

- by Hamidou Barry
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- Grafting, Burkina Faso, Drip / trickle irrigation, Yield

Two field experiments were carried out in El-Bosaily farm in the Northern coast of Egypt
during 2011/2012 and 2012/2013 seasons to study the response of the faba bean (Vicia faba L.,)
Sakha 3 cultivar to five different sowing dates (1st of October, mid of October and 1st of November,
mid of November and 1st of December) and three applied irrigation levels 0.60, 0.80 and 1.00 of IR
which applied by drip irrigation system. Plant height, leaf area index, total plant dry weight, biological
and seed yields, seed carbohydrate and protein contents as well as water use efficiency were
determined.
The results were as follows:
Vegetative growth traits as well as biological and seed yield of faba bean values were decreased as
sowing date delayed beyond the 1st of November. Meanwhile application of 0.60 of (IR) irrigation
treatments led to decline vegetative growth traits as well as biological and seed yield. Nevertheless,
the 1.00 irrigation treatments gave the highest grain yield. The final results showed that the 0.60
irrigation level gave the highest water use efficiency (WUE). Increasing irrigation water above
0.60 led to decrease in values of water use efficiency. Meanwhile, the highest water use efficiency
was obtained from the third sowing date (1st November) followed by second sowing date (mid.
October) while the lowest WUE value was obtained by the fifth sowing date (1st December).
Finally, the highest value of protein and carbohydrate contents in the faba bean seeds were obtained
by the lowest irrigation level (0.60IR) combined with the third sowing date (1st November).

- by Taher B Fayed and +2
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- Water, Sustainable agriculture, Irrigation, Water resources
- by Kamran Soomro
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- Soil Science, Agronomy, Agriculture, Drip / trickle irrigation

An Abstract-Fertilizers application plays an important in the production of fruits and vegetables. Over-application of fertilizers can slow down the growth and development of fruits and vegetables. The present research work was carried out to check the yield and growth rate of carrot in open field by using drip irrigation along with the application of different rates of poly-feed water soluble NPK (20-20-20) fertilizer. The field study was carried out on randomized complete block design (RCBD) having four different rates of poly-feed water soluble NPK fertilizer, i.e. (T 0 = control, T 1 = 0.7 grams per plant fertigation-1 , T 2 = 1 grams per plant fertigation-1 , and T 3 = 1.4 grams per plant fertigation-1) respectively. All the data analysis and statistical analysis for agronomic parameters were done through ANOVA procedure accordingly. The outcome of the conducted research tantamount that the poly-feed water soluble NPK (20-20-20) fertilizers application with different rates brought a positive effect in carrots cultivation under the open field arrangements. Amongst different treatments rates of NPK, treatment T 3 was observed to be more suitable and economical dose as it took the tallest carrot plants (44.67cm), highest number of leaves (5.52), highest leaf length (44.38 cm), the highest root core diameter (1.76 cm), maximum root shoulder diameter (5.09 cm), highest root length (19.11 cm) and highest root yield (11.07 t/ha) respectively. However, control plots showed unsatisfactory results regarding all the parameters. Therefore, from the current study it may be concluded that application of NPK (20-20-20) (treatment T 3 = 1.4 grams / plant fertigation-1 were suitable for optimum growth and yield of carrot. Application of fertilizers beyond this level seems to be an uneconomical and wasteful practice. Statistical analyses of all the research parameters are elaborated in Table I.

- by Engr Imran Arshad
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- Drip / trickle irrigation, Soil Fertility, Carrot, Fertigation in Vegetables

A soil box was used to investigate the water movement and soil water distribution around subsurface drip laterals with two emitters in the presence of a thin layer of polyacrylamide (PAM). Sandy soil was uniformly packed into a soil box. The PAM was applied at a rate of 29.3 kg ha-1 as a 0.01% solution by spraying it directly onto the soil surface at the required depths. With an operating pressure of 150 kPa and no PAM layer, the water consumption with a dripper line depth of 0.15 m was 12% lower than with a dripper line depth of 0.10 m. The greatest improvement in soil water-holding capacity after the addition of a PAM layer (47%) was observed when the dripper line was placed at a depth of 0.15 m under an operating pressure of 100 kPa. With a dripper line depth of 0.15 m and an operating pressure of 100 kPa, the average moisture content in the vertical planes below and above the dripper line directly increased by about 7.4 and 20%, respectively, with PAM layers at 0.25 and 0.30 m depths when compared with the moisture content with no PAM layer. The combination of a dripper line depth of 0.15 m, a PAM layer depth of 0.30 m and an operating pressure of 100 kPa will achieve optimal water management.

- by Dr. Mohamed Mattar and +1
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- Drip / trickle irrigation, Drip Irrigation, Subsurface Drip Irrigation, Wetting pattern
- by Salah El-Hendawy
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- Civil Engineering, Water Engineering, Agricultural Water Management, Seasonality

In the sustainable approach, now a day water use efficiency (WUE) is paramount. There is scarcity of water in Pakistan, so water extraction is done to meet the needs of irrigation and domestic purposes. Ground water level is depleting due to over pumping. To overcome water scarcity, it should be used effectively, which will help in reducing water scarcity. In a systematic use of water, drip irrigation should be the most preferred method to meet the water requirement of crops. In order to overcome these problems, a field experiment was conducted on potato crop under drip irrigation at a farm having Coordinates N 30’ 41.48” and E73’ 42.66” near Mazharabad in Depalpur. The objectives of this research were to determine the Fertilizer use, water use efficiency (WUE) of potato and economic analysis of drip irrigation.
CROPWAT Model was used to determine the water requirement and Irrigation requirement of potato. Two treatments were used 1st one is potato on furrow irrigation and 2nd one is potato with drip irrigation. Collected data from the experiments showed that 56% water saved through drip irrigation system as compared to furrow and 41% Fertilizer saved in drip irrigation.
Fertilizer use Efficiency (FUE) of Drip and Furrow Irrigation system was 87 and 42
respectively. Benefits-cost ratio of Drip and furrow 1.02 and 0.38 respectively. Overall Drip Irrigation was economical system of Irrigation. This Concluded that drip irrigation system is more feasible for the production of field crop especially vegetables.

Among the factors affecting the movement of water in the soil are soil properties (structure and texture). The rate of components of soil minerals and organic material has an effect on its bulk density. As the surface soil has organic matter more than subsurface soil in general, the bulk density increases with soil depth, so the research aims to study the effect of changing soil bulk density with depth on wetting front advance under a trickle line source. The experimental work included a nine laboratory tests for monitoring the advancement of the wetting front with time, The water advance and water distribution measurement are carried out for three cases of the soil profile with the change of bulk density along soil depth (0.00923,0.00462,0) gm/cm 3/cm: first case with the soil changed bulk density from 1.2 gm/cm 3 at the soil surface and gradually to 1.8 gm/cm 3 at a maximum depth of the profile, the second case with the soil changing bulk density from 1.5 gm / cm 3 to 1.8 gm / cm 3, and the third case homogeneous soil with bulk density 1.2 gm / cm 3.and using three application flow rates 1.3,2.6,3.9 cm 3 / min / cm.
The study showed that with the increase in the change of bulk density along soil depth there is a small increase in the horizontal advance and almost non-existent this increase in vertical advance while they are clear and tangible in diagonal advance. It also showed that the amount of the increase in the vertical advance is greater than in the horizontal advance and be among in diagonal advance when increasing the application flow rate, and all of the horizontal advance, vertical advance and the diagonal advance of the wetting front increases with the decrease of the application flow rate and that when applied the same volume of water.

- by Dr.Samir Ismail
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- Drip / trickle irrigation

Root length density distribution Normalized root length density distribution Cotton Film mulched drip irrigation Soil water and salinity stresses a b s t r a c t Root length density (RLD) distribution information is essential to crop growth and soil water/solute transport predictions and for rational irrigation scheduling and crop management. Unfortunately, measuring RLD accurately in the field is difficult and time-consuming, especially for row crops such as cotton. Field experiments were conducted over two seasons (Exp. 1 and 2 in 2011 and 2012, respectively) to investigate two-dimensional RLD distribution of cotton under film mulched drip irrigation in Xinjiang, China. Different RLD distributions were created by varying row and drip line spacing, irrigation water salinity, irrigation volume and fertilizer application rate. Both distributions of measured RLD and calculated normalized RLD (NRLD), the root length allocation proportions of a plant at different relative depths, were found to decrease with depth, concentrating within the upper soil layers with nearly negligible differences along the horizontal direction. NRLD values in Exp. 2 were pooled together and simply generalized as a vertical one-dimensional decreasing function with just one fitted coefficient of a = 2.06, which was employed to characterize the maximum value of NRLD at the soil surface and its downward decreasing rate. The generalized function was verified to be in good agreement with the measured NRLD distributions of cotton in Exp. 1, and then further improved using all the NRLD data from Exp. 1 and 2. The improved function (with a = 1.96) was shown useful in estimating RLD distribution and simulating soil water flow and salinity transport in a soil-cotton system.

- by Alon Ben-Gal
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- Cotton, Drip / trickle irrigation, Roots, Root length density
- by Mohammad ElNesr
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- Computer Aided Design, Drip / trickle irrigation

A study was conducted at the research farm of Central Soil Salinity Research Institute, Karnal, to evaluate the effect of salinity of irrigation water on the yield of okra (Abelmoschusesculentus L. Moench) under drip irrigation. The experiment was conducted in randomized block design with 4 levels of saline irrigation water (ECiw = 0.2, 2.0, 4.0, 8.0 dS.m-1) in three replications. Significant change in the yield of okra (Var: Mahyco-10 Hy) was observed at 1% level of significance. It was found that even at 8 dS.m-1 irrigation water salinity, 77% of okra yield to the check could be obtained. Highest water use efficiency was with available fresh water of 0.2 dS.m-1 at 0.49, and for the treatments of 2.0, 4.0, 8.0 dS.m-1 it was observed at 0.49, 0.46 and 0.38 t.ha-1.cm-1, respectively.

The performance of drip irrigation and subsurface drip irrigation (SDI) laterals has been compared. Two emitter models (one compensating and the other noncompensating) were assessed. Field tests were carried out with a pair of laterals working at the same inlet pressure. A procedure was developed that recorded head pressures at both lateral extremes and inlet flow during irrigation. Both models showed similar behavior and soil properties affected their discharge. On the other hand, the performance of a field SDI unit of compensating emitters was characterized by measuring pressures at different points and inlet flow. Finally, the distribution of water and soil pressure in the laterals and the unit were predicted and irrigation uniformity and soil pressure variability were also determined. Predictions agreed reasonably well with the experimental observations. Thus, the methodology proposed could be used to support the decision making for the design and management of SDI systems.

- by Leonor Rodriguez Sinobas and +1
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- Agricultural Engineering, Civil Engineering, Design, Hydraulics

The effects of water temperature and structural parameters of a labyrinth emitter on drip irrigation hydraulic performance were investigated. The inside structural parameters of the trapezoidal labyrinth emitter include path width (W) and length (L), trapezoidal unit numbers (N), height (H), and spacing (S). Laboratory experiments were conducted using five different types of labyrinth-channel emitters (three non-pressure compensating and two pressure compensating emitters) commonly used for subsurface drip irrigation systems. The water temperature effect on the hydraulic characteristics at various operating pressures was recorded and a comparison was made to identify the most effective structural parameter on emitter performance. The pressure compensating emitter flow exponent (x) average was 0.014, while non-pressure compensating emitter’s values average was 0.456, indicating that the sensitivity of non-pressure compensating emitters to pressure variation is an obvious characteristic (p < 0.001) of this type of emitters. The effects of water temperature on emitter flow rate were insignificant (p > 0.05) at various operating pressures, where the flow rate index values for emitters were around one. The effects of water temperature on manufacturer’s coefficient of variation (CV) values for all emitters were insignificant (p > 0.05). The CV values of the non-pressure compensating emitters were lower than those of pressure compensating emitters. This is typical for most compensating models because they are manufactured with more elements than non-compensating emitters are. The results of regression analysis indicate that N and H are the essential factors (p < 0.001) to affect the hydraulic performance.

A new method to barricade water deep percolation was investigated. This method was called 'The hydraulic barrier technique'. The method involves burying a secondary dripper line under the primary one in order to increase the deep layers' water content whereas to minimize matric potential in these layers. So that to increase the side movement of water from the primary dripper line. The method was validated by a field experiment in Sinai sandy soil. The field experiment tested four burying depths of primary dripper line, with and without the hydraulic barrier, compared with the physical barrier. Two crops were used, Jerusalem artichokes (Tartoufa) as example to tuber roots, and tomato as fibrous root. The results showed that the physical barrier extremely increased both crops more than double its normal in the absence of physical barrier value (2.35 for Tartoufa and 2.19 for Tomato), and the hydraulic barrier existence increased the total crop yield of Tartoufa by about 12% and marketable yield by 47%. Reduction of Tomato yield was found due to existence of hydraulic barrier by about 25%. The Tartoufa yield increased directly proportional to the burying depth of the primary lateral while the situation is inverted in the tomato. The hydraulic barrier acted the same like the physical barrier when the gap between the two dripper-lines getting narrower.

Inadequate oxygen concentration in the root zone is a constraint to plant performance particularly in heavy, compacted and/or saline soils. Sub-surface drip irrigation (SDI) offers a means of increasing oxygen to plant roots in such soils, provided irrigation water can be hyper-aerated or oxygenated. Hydrogen peroxide (HP) at the rate of 5 litre ha−1 at the end of each irrigation cycle was injected through SDI tape to a field-grown zucchini (courgette) crop (Cucurbita pepo) on a saturated heavy clay soil in Queensland, Australia. Fruit yield, number and shoot weight increased by 25%, 29% and 24% respectively due to HP treatment compared to the control. Two pot experiments with vegetable soybean (Glycine max) and cotton (Gossypium hirsutum) compared the effectiveness of HP and air injection using a Mazzei air injector (a venturi), throughout the irrigation cycle in raising crop yield in a heavy clay soil kept at saturation or just under field capacity. Fresh pod yield of vegetable soybean increased by 82–96% in aeration treatments compared with the control. The yield increase was associated with more pods per plant and greater mean pod weight. Significantly higher above ground biomass and light interception were evident with aeration, irrespective of soil water treatment. Similarly cotton lint yield increased by 14–28% in aeration treatments compared with the control. The higher lint yield was associated with more squares and bolls per plant which accompanied greater above ground biomass and an increase in root mass, root length and soil respiration. Air injection and HP effected greater water use, but also brought about an enhancement of water use efficiency (WUE) for pod and lint yield, and increased leaf photosynthetic rate in both species but had no effect on transpiration rate and stomatal conductance per unit leaf area. Aeration-induced enhanced root function was arguably responsible for greater fruit set and yield in all three crops, while in vegetable soybean greater canopy cover, radiation interception and total vegetative biomass were responsible for additional yield benefit. Increased aeration of the root zone in heavy clay soils employing either air injection or HP proved beneficial to SDI irrigated crops, irrespective of the soil water conditions, and can add value to grower investments in SDI.

- by david midmore
- •
- Photosynthesis, Biomass, Biology, Biological Sciences

A study was conducted to determine the effects of different drip irrigation regimes on yield and yield components of cucumber (Cucumbis sativus L.) and to determine a threshold value for crop water stress index (CWSI) based on irrigation programming. Four different irrigation treatments as 50 (T-50), 75 (T-75), 100 (T-100) and 125% (T-125) of irrigation water applied/cumulative pan evaporation (IW/CPE) ratio with 3-day-period were studied.

Estimate crop water use efficiency (WUE) Leaf area index (LAI) Biomass a

- by Serdar Polat
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- Civil Engineering, Biomass, Water Engineering, Agricultural Water Management

An interactive computer enabled software namely IRRIPRO was used in order to design and plan viable drip irrigation systems. This software is proficient enough in planning network layout, hydraulic designing and above all simulations to obtain results. This software can also provide requisite cost estimation of new as well as existing drip irrigation. IRRIPRO has the diverse quality to calculate and design many other hydraulic parameters. It is a helping tool for water resource engineers in designing, testing, analyzing any other alternative design on precision and economical parameters. It is equally useful in cost estimation of those systems which are not designed with the help of IRRIPRO software. The research study has been conducted in a greenhouse at western region of Abu Dhabi UAE to check the operational reliability, efficiency, dependability and harmony of the existing drip irrigation system. The comparative study revealed that the drip irrigation achieved high CU and DU which imply that the existing drip irrigation system was designed on the basis of proper scaling and dimensions. The CU on average basis for the system was found to be 96.4990% (observed) and 99.9796% (simulated) respectively. Similarly, the DU on average basis for the system was found to be 94.3605% (observed) and 99.8822% (simulated) respectively. EUa of the system using pressure compensated type emitters with the length of laterals 16 meters with an average observed and simulated value was found 99.2192% and 99.99316% respectively. The comparison of experimental and simulated results confirms that the application uniformity seems to be satisfactory and the existing drip irrigation unit was designed properly.

- by matin jafari
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- Drip / trickle irrigation

A field experiment was conducted to study the effect of varying water application and soil pH on the growth parameters during the establishment of litchi (Litchi chinensis Sonn.) plantation in a partially reclaimed alkali environment. The plant growth parameters such as plant height and girth at collar were studied. Hydraulic performance of drip system was monitored by observing the individual and plant wise emitter discharge. The Christiansen's Coefficient of Uniformity (CCU), Wilcox-Swailes Coefficient of Uniformity (WSCU), Statistical Coefficient of Uniformity (SCU), Low Quarter Distribution Uniformity (SDUIq), and Coefficient for Emitter Flow Variation (CEFV) for the rate of water application were determined. The average value of CCU remained close to 0.63 and 0.75, respectively, on emitters' and plant basis when 4 drippers were employed per plant. Different levels of soil pH as experienced by the litchi plants were grouped into seven soil pH groups viz. less than 7.75, 7.75-8.00, 8.00-8.25, 8.25-8.50, 8.50-8.75, 8.75-9.00 and more than 9.00. In each of the above pH groups, different emitter discharges were observed. The plant wise discharges received in each pH group were further sub-divided and grouped in less than 10, 10-15, 15-20, 20-25, 25-30 and above 30 liter per hour (Ih?¹). The plant growth parameters were significantly different at different soil pH levels. The plant mortality was high and plant height and girth at collar reduced when the soil pH exceeded 8.5. A positive linear trend was observed in growth parameters and the application of discharge at or below a pH level of 8.5, after which the trend was reverse.

- by Chandra Kant Saxena
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- Drip / trickle irrigation, Uniformity

The purpose of this study was to assess the efficiency of chemical approaches to manage coffee leaf rust (CLR) in drip-irrigated coffee trees. Coffea arabica plants of the Catuaí Vermelho IAC 144 cultivar were subjected to applications of protective and systemic fungicides . Foliar application of the systemic fungicide epoxiconazol was performed at predefined dates (calendar) and after ascertaining that CLR was present in 10% of plants. A fungicide + systemic insecticide (cyproconazol + thiamethoxam) was applied on the soil at the beginning of the rainy season. The results showed that a strategy based on two foliar application calendar for epoxiconazol at pre-determined times in December (0.6 L c.p.ha −1 ) and March (0.4 L c.p.ha −1 ) controlled CLR more effectively than four foliar application calendar for the protective fungicide copper oxychloride applied in December, January, February and March, at 3.0 kg c.p. ha −1 , application on the soil of fungicide + insecticide (cyproconazol + thiamethoxam) at the beginning of the rainy season and sampling and decision-making with foliar application of the systemic fungicide epoxiconazol at 0.6 L c.p.ha −1 after ascertaining a 10% disease incidence. There was no significant difference in yield among the different strategies of fungicide applications across the six studied crops. The averages of coffee berry yield of all the treatments with fungicides either protective and or systemic were 30.80 (60-kg bags of processed coffee per hectare) which is 22.4% higher than the control treatment. In conclusion all the strategies can be used to control CLR including application of systemic fungicide after ascertaining a 10% disease incidence. The number of application of systemic fungicide epoxiconazol at 10% disease incidence was approximately 40% less than in a calendar system. This is the first report of the effective control of CLR with systemic fungicide epoxiconazol either spraying on the plants (performed at predefined dates or after ascertaining a 10% disease incidence) or through the application of cyproconazol on the soil in drip irrigation trees.

- by Paulo Cecon and +1
- •
- Microbiology, Decision Making, Irrigation, Pest Management

Native grass, forb, and shrub seed is needed to restore rangelands of the U.S. Intermountain West. Fernleaf biscuitroot [Lomatium dissectum (Nutt.) Mathias & Constance] is a desirable component of rangelands. Commercial seed production is necessary to provide the quantity and quality of seed needed for rangeland restoration and reclamation efforts. Fernleaf biscuitroot has been used for hundreds if not thousands of years in the western United States as a source of food and medicine. Knowledge about fernleaf biscuitroot is confined to ethnobotanical reports, evaluation of some of its chemical constituents, and its role in rangelands. Products derived from fernleaf biscuitroot are sourced from wild plant populations. Little is known about fernleaf biscuitroot cultivation or its seed production. Variations in spring rainfall and soil moisture result in highly unpredictable water stress at flowering, seed set, and seed development of fernleaf biscuitroot. Water stress is known to compromise seed yield and quality for other seed crops. Irrigation trials were conducted at the Oregon State University Malheur Experiment Station at Ontario, OR, a location within the natural environmental range of fernleaf biscuitroot. It was anticipated that supplemental irrigation would be required to produce a seed crop in all years. Fernleaf biscuitroot was established through mechanical planting and cultivation on 26 Oct. 2005 in a randomized complete block design with four replicates; plot size was 9.1 m 3 3.04 m wide. Irrigation treatments were 0 mm, 100 mm, and 200 mm/year applied in four equal treatments 2 weeks apart, timed to begin with flowering and continue through seed formation. First flowering occurred in the third year after planting. Seed production increased from the fourth through the sixth year. Optimal irrigation for seed production was calculated as 140 mm/year.

- by Clinton Shock and +1
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- Horticulture, Water Engineering, Drip / trickle irrigation, Drip Irrigation

Rao, K.V. Ramana, Saxena, C. K. (2014). Advances in Micro Irrigation Systems and Fertigation under Covered and Open Cultivation, ICAR - Central Institute of Agricultural Engineering Bhopal 462 038 (India), Manual No: CIAE/IDED/2014/441, p... more

- by Chandra Kant Saxena
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- Horticulture, Greenhouses, Drip / trickle irrigation, Fertigation

In order to optimize the usage of water in agriculture, it is necessary to increase the efficiency of irrigation systems, especially those of surface irrigation. One of the steps to be made to achieve this goal is the optimal design of surface irrigation. It this article the design variables of furrow irrigation, that includes length of furrow, inflow rate and irrigation time (time of cutoff), were calculated to minimize the irrigation costs, the objective function, and to obtain a maximum application efficiency. The objective function encompasses water, labor, head ditch and furrow digging (ditch constructions) costs. Labor cost is irrigation time's function and the latter is dependent on water advance period in the furrows. Therefore, it is necessary for the objective function to apply explicit and accurate equation in order to calculate time of advance. Because in none of the accurate methods for furrow irrigation design, such as zero-inertia modeling, the advance time is explicitly calculated, therefore in this research the equation obtained by Valiantzas, which he extracted from the results of zero-inertia modeling, was used. In the objective function in addition to the design variables the specifications of soil, furrow and net irrigation requirement also exist. Therefore, it is possible to calculate design variables and afterwards the irrigation efficiency for different soil types and plant types. In this article this task was performed with different soil types and in accordance with different requirements for irrigation and the results are presented in the tables.

- by Kaveh Ostad-Ali-Askari and +3
- •
- Irrigation, Irrigation water use efficiency, Irrigation Engineering, Irrigation water Management

The aim of this study was to evaluate whether it is possible to conserve water and improve yield using canopy cover in order to adjust the amount of water needed for drip-irrigated tomatoes. The experiments were carried out using field-grown tomatoes (Lycopercion esculentum cv. Dual Large, F1) in Central Anatolia, Turkey from 2003 to 2005. The experimental design used split-plots in randomised blocks with 3 replications. The main plots in this study were: I 1 , constant Class A pan evaporation (Ep) (i.e. K = 1.0) throughout the irrigation season; I 2 , varying Ep proportion according to crop development stage (i.e. planting time to flowering stage 0.50; flowering stage to first harvesting 1.0; and first harvest to last harvest 0.75. In subplots, wetted area percentages or canopy cover were used. In K 1 , the wetted area percentage measured 90% of the experimental site. In K 2 , the wetted area percentage varied depending on the canopy cover. In K 3 , the percentage of wetted area was set to a value of 65% throughout the irrigation season.

- by Oner Cetin
- •
- Agronomy, Water Engineering, Interaction, Agriculture

- by Raul Edwin Zavala Sanchez
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- Agricultural Engineering, Civil Engineering, Design, Hydraulics

India is facing innumerable challenging problems associated with land and water resources. Declining land resource, depleting water resource and decreasing resource productivity are matters of grave concern. While an estimated 8.5 million ha of agricultural lands have turned barren because of excess salts, the receding availability of the fresh quality water for agriculture aggravating over time. Thus, use of water saving technologies and/or technologies that would allow growing crops on salt-affected soils or with the use of poor quality waters would play an increasingly important role in the twin task of utilizing salty land and water resources for agriculture. The use of drip irrigation seems to be the most viable method of irrigation considering the limitations set forth by poor quality land and water resources. The expansion potential of drip irrigation can be gauged from the fact that only 0.36 million ha is currently under drip irrigation against a potential of 27 million ha. Concerted efforts are being made across the country to examine the suitability and adaptability of drip irrigation for growing a wide range of agricultural and horticultural crops under various agro-climatic conditions. A critical review of several research studies has been made to highlight increase in water use efficiency or water saving for several crops. On the basis of drip irrigation experiments conducted across India, the performance of drip irrigation in salt affected soils and water environments has been highlighted. An attempt to develop pitcher irrigation as an indigenous alternative to drip irrigation to minimize initial investment cost is also included.

- by Chandra Kant Saxena
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- Soil Salinity, India, Drip / trickle irrigation, Drip Irrigation

Abstract: There were some problems that face continuous drip irrigation system in Egypt, such as emitter clogging, due to the narrow paths of water which give small discharge and in sandy soil, the depth of wetting pattern is relatively higher than the width. They cause deep percolation beyond root zone. Thus the need to increase the width of wetting pattern and use of high emitter discharge suggest the use of pulse drip irrigation.
The information on depths and widths of wetted zone of soil plays the greatest role in design and management of drip irrigation system. There is a lack of models to predict wetting pattern under pulse and intermittent flow regime, since the applicability of the available models were limited to continuous flow regime only. Therefore, the objective of this research was to develop a dimensional analysis model to estimate both depth and width of wetting pattern under different flow regimes. Thus, a model was developed using semi-empirical approach and dimensional analysis method for determining geometry of wetted root zone under. The predicted values of wetted depth and width were compared with those obtained through laboratory experiments conducted in same soil. Experiment included determination of maximum depths and widths of wetted zone after 1, 2, 3, 4 h of water application under different flow regimes. Predicted and observed values were compared to test model applicability in laboratory conditions. On the basis of root mean square, mean error and model efficiency parameters model performance was found good. Thus, developed models can be used to predict wetting pattern under continuous, intermittent and pulse flow with line source of water application. Pulse flow results showed that the wetted width increased and wetted depth decreased as the operating on-time decreased for the same amount of applied water. As the pulsed flow was increased from six to twelve times the continuous flow, deep percolation was reduced and horizontal spread increased. This result shows the advantage of pulse flow, for reducing the deep percolation of water under the crop root zone, while obtaining a wide horizontal spread of wetting. This enables using a highly discharge emitter with the same amount of water.

- by Dr.Samir Ismail
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- Wetting and Spreading, Modeling, Soil moisture, Drip / trickle irrigation

Seepage problem and channel transition efficiency is one of the most important issues in managing and exploiting irrigation networks. Seepage rate should be minimized in the design and construction of irrigation channels. Anyway several methods have been represented to calculate seepage rate. Some methods that are numeral have their own complexity, and some methods are empirical. Due to the fact that the nature of the flow in the channels and the seepage of the walls are spatially varied flow, in this study, the governing dynamical equation is used and combined with the Chahar and Swamee equation. The final differential equation is solved by finite difference method (FDM), and the depth and flow rates of different cross sections of a channel are obtained. From the difference of flow rate in two cross sections, the seepage flow rate can be calculated. The information required for this method is the flow rate and flow depth at a downstream control channel, the hydraulic conductivity of the channel bed, the geometric characteristics of the channel, and the distance between the water table and the bottom of the channel. This model can be used for calculation of the transmission efficiency too.

A field experiment was carried out during the two successive autumn seasons of 2013 and 2014
under open field conditions in protected cultivation site, Agriculture Research Centre, Giza
governorate, Egypt. The study was investigating the effects of different irrigation levels (50, 75 and 100% of crop evapotranspiration (ETc)) and different sources of fertilizers (inorganic fertilizers (control), cattle manure, compost and vermicompost) on some soil chemical characteristics and vegetative growth, yield and water use efficiency of head cabbage. Obtained results showed that soil pH decreased at the end of experiment with a range of 0.08-0.30, compared with before cultivation, with high decreases by 50% of ETc combined with vermicompost. ECe, on the other hand, increased due to different agricultural activities such as adding chemicals and fertilizers,

- by Mohamed Abdrabbo
- •
- Soil Science, Water, Sustainable agriculture, Irrigation