Drip Irrigation Water Research Articles

IDE in Nicaragua: quest for sustainability

Synopsis International Development Enterprises (iDE), a non-profit organization, won numerous awards for its poverty alleviation efforts through the sale of low-cost irrigation technologies to the Base of Pyramid (BoP) farmers around the world. This case discusses iDE’s entry into Nicaragua and the challenges this global social enterprise faced in bringing drip irrigation and other water technologies to the rural subsistence coffee farmers in Nicaragua. It presents the tough decisions it faced in 2012 regarding the future of its for-profit social business, iDEal Tecnologias, in Nicaragua. This case captures the tension in hybrid social enterprises. Research methodology This case was developed through the following primary sources as well as some secondary sources. Primary: discussions with iDE’s CEO Doerksen, Urs Heierli (Coordinator of iDE’s operations in Nicaragua), and Skype conversations with iDEal Tec’s Country Director, Nadja Kränzlin. Secondary: documents provided by the company and other publicly available sources. Relevant courses and levels This case is intended for use in undergraduate, graduate, and executive courses in: social entrepreneurship, non-profit management, and managing sustainable businesses. It may also be used in the sustainability module of courses in international business/management/marketing, and business strategy and policy. It would be best to position this case toward the middle or latter half of the course as it is an integrative case that challenges students to evaluate the sustainability of a social enterprise from multiple perspectives. Theoretical bases The theoretical bases for this case are: defining and implementing a sustainable strategy in hybrid social enterprises. Serving BoP customers with a vision of enabling prosperity.

Water pillow irrigation versus drip irrigation with regard to growth and yield of tomato grown under greenhouse conditions in a semi-arid region

Increasing world population entails an increase in agricultural productions. Climate change and resultant global warming points out more efficient use of soil and water resources. Irrigation is the most significant input in agriculture to increase yield levels. Therefore, efficient water use is a critical issue in irrigation practices to have ‘more crop per drop’. Water pillow is a new irrigation method with quite high irrigation water efficiency. In this study, efficiency of water pillows irrigation method was investigated in tomato irrigation under greenhouse conditions and results were compared with drip irrigation. Amount of applied irrigation water was measured as 416.3mm in water pillows and 798.7mm in drip irrigation. The value in water pillows was 52% less than drip irrigation. The total yield was 360.11tha−1 in water pillows and 306.62tha−1 in drip irrigation method. Average yield per plant was 11.31kg in water pillows and 9.63kg in drip irrigation. The differences in yields of treatments were found to be significant (P<0.05). Weed development was observed in drip irrigation, but not observed in water pillows. Physico-chemical analyses on tomatoes from water pillows and drip irrigation revealed that tomatoes irrigated with water pillows had better pH, titration acidity, brix, total dry matter and color values than the tomatoes irrigated with drip irrigation.

Effect of ridge planting on reclamation of coastal saline soil using drip-irrigation with saline water

The ridge planting (RP) system has been widely used in agricultural production and demonstrated as an effective agronomic practice. However, it is not known if it can be used to reclaim saline soil for landscape construction. Our objective was to analyze the soil characteristics and Chinese rose (Rosa chinensis) performance at five irrigation water salinity levels of 0.8, 3.1, 4.7, 6.3 and 7.8dS/m under RP and flat planting (FP) systems in the process of reclamation of coastal saline soils using drip-irrigation. The experiment started in 2012 using two soils (silt and sandy loam) in the coastal saline regions, north of the Bohai Gulf, China. The RP system significantly enhanced salt leaching in total soil profiles, especially the deep soil profile, and improved emergence and survival of Chinese rose compared with FP. The RP system also improved the salt tolerance of Chinese rose to the irrigation water salinity level. Thus, the RP system (ridge height<15cm and ridge width<50cm) was effective in reclamation of coastal saline soils by planting small shrubs and herbaceous plants under drip-irrigation with saline water. In this respect, it is expected that RP will be more sustainable and effective than FP for reclamation of saline soils using saline water drip-irrigation in construction of ecological landscapes in coastal regions.

Effects of soil moisture conservation practice, irrigation and fertilization on Jatropha curcas

A field experiment was conducted on an Ultic Haplustalf at the Kanchanaburi Research Station, Muang district, Kanchanaburi province, western Thailand between July 2011 and June 2012. Split plots in a randomized complete block design with four replications were employed, having eight main plots (soil moisture conservation practice and irrigation, W1–W8) and 2 sub plots (fertilization, F1 and F2). Jatropha curcas (KUBP 78-9 Var.), having been planted at 2 × 2 m spacing, was aged 2 yr when the experiment was commenced. The highly significantly heaviest 100-seed weight of 42 g was obtained 1 mth after water irrigation which had been applied at the rate of 16 L/plant, particularly in the treatment with crop residue mulching (W8) but there were no significant differences among the other treatments where irrigation had been applied (W5–W7). Fertilization and a combination between different fertilizers and soil moisture conservation schemes plus irrigation showed no different effect on the weight of 100 seeds throughout the year of measurement. Growing J. curcas with drip-irrigated water at the rate of 16 L/plant applied every 2 d and crop residue mulching (W8) significantly gave the highest seed yield of 1301.3 kg/ha at 15% moisture content. There were no significant differences among the seed yields from the plots applied with the same amount of irrigated water but with no mulching (W7) and half that amount of irrigated water with crop residue mulching (W6), producing yields of 1112.0 kg/ha and 1236.3 kg/ha, respectively. Three-year-old J. curcas gave inferior seed yield when grown with no irrigated water supply (W1–W4). The application of 50–150–150 kg/ha of N–P2O5–K2O significantly induced a higher amount of seed yield (933.9 kg/ha) than did the addition of 93.75–93.75–93.75 kg/ha of N–P2O5–K2O (786.3 kg/ha). The interaction between soil moisture conservation plus irrigation and fertilizer was clear. Applying 50–150–150 kg/ha of N–P2O5–K2O together with water irrigation at the rate of 16 L/plant (W7F2) significantly promoted the greatest seed yield of 1415.2 kg/ha. However, irrigated water can be reduced to 8 L/plant in combination with crop residue mulching and the addition of 50–150–150 kg/ha of N–P2O5–K2O (W6F2) and the plants still performed well, producing a seed yield of 1356.4 kg/ha. In addition, with no irrigation, none of the moisture conservation practices (W2–W4) showed any significant effects regardless of the different fertilizers applied.

EFEITO DA APLICAÇÃO DE UREIA E DE CLORETO DE POTÁSSIO POR FERTIRRIGAÇÃO NA VAZÃO DOS EMISSORES E EM PARÂMETROS QUÍMICOS DO SOLO

The fertirrigation has been incorporated to production systems of various fruit trees in Brazil, resulting in greater demand for knowledge of this technology in relation to its effect on the dynamics of solutes in the soil. Given this context, this study aimed to evaluate the effects of the use of fertiliser urea and potassium chloride through irrigation water on the issue of water by issuers and on soil chemical attributes (pH and electrical conductivity) in papaya crop for drip irrigation. The evaluations were conducted within an experiment outlined in randomized blocks, where the treatments consisted of five doses of N and five doses of K2O, totaling 10 treatments. Were installed in a solution in the soil to the horizontal distances of 0.03 m, 0.20 m, 0.40 m and 0.60 m from the dripper, the depths of 0.20 m, 0.40 m, 0.60 m and 0.80 m near the plant, in order to simulate a two-dimensional plane. The results showed that the use of urea and potassium chloride had no effect of clogging in the issuers in the period studied, nor had the effect of reducing the soil pH or changes in the level of salinity. The range of potassium applied via water drip irrigation by source of potassium chloride was 0.40 m in the horizontal distance from the dripper and in depth and the region of the volume wet with greater variation in the concentration of potassium occurred between the dripper and the plant.

Study on rules of dynamic variation of nitrogen in soil after reclaimed water drip irrigation

Reclaimed water belongs to one of makeup waters to be applied to agricultural production, which can not only reduce the quantity of wastewater effluent, but also reduce the quantity in demand of good-quality water, and is key element in utilization of limited water resources. Through field experimental method and taking drip irrigation, the regulation of reclaimed water drip irrigation on dynamic variation of nitrogen in soil was studied in this paper. The results indicate that compared to the contrast treatment, NH4+-N content in the surface layer increased sharply in the initial period after reclaimed water drip irrigation, and then decreased significantly in the fifth day, and down to the level before irrigation on the ninth day, which was uniform between soil layers. NO3-N content under all the treatments presented the almost same trend in soil profile: NO3-N content increased with the soil depth, indicating an obvious tendency of NO3-N leaching down to lower layers. However, at the depth of 100–150 cm, NO3-N content began to decrease. When reclaimed water drip irrigation was used for cucumber planting, NO3-N content in different layers at the ending of the growing period increased by 38.20%, 44.67%, 34.94%, 30.88%, respectively, than that before planting.

Evaluation on the responses of maize (Zea mays L.) growth, yield and water use efficiency to drip irrigation water under mulch condition in the Hetao irrigation District of China

Hetao Irrigation District (HID) is characterized by less rainfall and high evaporative, but it is a main grain production region in China. Increasing water use efficiency is an appropriate way to fulfill the sustainable agriculture development because the allocated water for HID will be reduced in the future. In this study six irrigation treatments with irrigation amounts being the 20, 40, 60, 80, 100, and 120% of crop water requirement (ETc) were carried out for maize crop (Zea mays L.) in the HID under mulch-dripped irrigation condition in 2013 and 2014 years. Soil water and electrical conductivity, plant growth factors, harvest factors and yield were investigated, and crop actual evapotranspiration (ETcact), water use efficiency (WUE) and irrigation water use efficiency (IWUE) were calculated. Results showed that soil water and salt mainly varied in the upper 60cm soil layer. At harvest, salt accumulation was found in the upper soil layer and the highest salt accumulation was in the least irrigation treatment. Growth factors and harvest factors were reduced significantly (P<0.05) for irrigation depth of less than 40%ETc compared to 80–120%ETc, but they were not significantly (P>0.05) different from 80 to 120%ETc. The highest grain yield were found at 100%ETc, then yield decreased with irrigation depth decreasing due to the reductions of ear size and 100-grain weight. ETcact ranged from 200 to 430mm in the two seasons, and linearly increased with the irrigation depth increasing. The highest WUE was found at 60%ETc, while IWUE was decreasing with irrigation depth increasing. Fully considering maize yield, water use efficiency, soil salt balance and water resources availability of Yellow river, full irrigation with 100%ETc is recommended with the objective of the highest yield when water resources can satisfy water demand of irrigation and economic development, while water deficit of 20–30% is recommended with the objective of getting the highest WUE and little yield loss (4–8%) under mulched drip irrigation in HID.

Chemical Clogging of Emitters and Evaluation of Their Suitability for Saline Water Drip Irrigation

AbstractDrip irrigation with saline water is one of the most effective methods to ease the current worldwide water shortage. However, there are more ionic compositions in saline water, resulting in easy clogging of drip irrigation emitters. In this study, we selected five common emitters as study subjects and conducted a saline water drip irrigation experiment in the Hetao Irrigation District (Inner Mongolia, China). The results showed that, as the running time increased, the discharge ratio variation (Dra) and coefficient of uniformity (CU) both declined. The Dra and CU of cylindrical emitters decreased gently, while those of flat emitters showed a 'slow–fast' downward trend. The Dra of the five different emitters decreased to 46.3–78.6% and the CU dropped to 23.5–85.0% over the course of the experiment. Cylindrical emitters with higher flow showed better anti‐clogging capacity. The temporal and spatial distribution of clogging materials within emitters differed. Specifically, the dry weights (DW) of clogging materials in different positions occurred in the order of DWhead &lt; DWmiddle &lt; DWend laterally, and clogging materials accumulated gradually with time. The average clogging materials distribution density showed a significant negative linear relationship with Dra and CU (R2 = 0.81 and 0.88). It indicated that as the clogging materials accumulated, the anti‐clogging capacity of emitters degraded. The chemical constituents of the clogging materials in the different emitters were the same (Ca + Mg carbonate, quartz, silicate and litter sodium chloride). The amounts of Ca + Mg carbonate showed a strong positive correlation with Dra and CU (R2 = 0.93 and 0.92), while the amounts of quartz showed a remarkable negative linear relationship with Dra and CU (R2 = 0.85 and 0.87). The main material responsible for emitter clogging was calcium carbonate deposits, which accounted for &gt;88.1% of the total. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Soil salinity, leaching, and cotton growth as affected by saline water drip irrigation and N fertigation

ABSTRACTSaline water (SW) irrigation is necessary in parts of the world where supplies of good quality water are limited. The aim of this study was to learn more about the use of saline irrigation water in drip-irrigated cotton. Therefore, a 5-year field experiment consisted of a 3 × 2 factorial complete randomized block design with three levels of irrigation water salinity (0.35, 4.61, and 8.04 dS m−1) and two N application rates (240 and 360 kg N ha−1) was carried out in arid regions of northwestern China. The results indicated that drip irrigation with SW (4.61 or 8.04 dS m−1) increased average soil water content and average soil salinity in the 0–100 cm depth. SW irrigation increased leachate –N concentrations. Nitrogen rate significantly affected leachate volume and salt concentration in some years; however, the trends were inconsistent. The treatment with 8.04 dS m−1 irrigation water significantly reduced cotton growth, yield, and N uptake in all the five cropping seasons. In contrast, the treatment with 4.61 dS m−1 water increased cotton growth, yield, and N uptake in the first year, but in the third, fourth, and fifth years, cotton growth, yield, and N uptake were significantly lower in the treatment with 4.61 dS m−1 water than in the treatment with 0.35 dS m−1 water. Cotton growth and yield increased as N application rate increased; however interactive effects between water salinity and N rate on cotton growth and yield were generally not significant. We conclude that drip irrigation with SW (EC>4.6 Ds m−1) reduces cotton yield and increases the risk of salt and –N leaching to groundwater. Additional N fertilizer input may overcome some of the negative effects of salinity on cotton growth, but also increases the potential risks for nitrate leaching.

Effects of Salt Water Drip Irrigation on Jujube Roots Soil Available Nitrogen Distribution: A Security Assurance Perspective

Field experiment was used in this research to study influences brought by salt water with different degrees of mineralization to distribution characteristics of soil available nitrogen and nitrate nitrogen in red jujube root zones when the salt water drip irrigation was carried out to jujubes. It is shown in the results that the distribution content of soil available nitrogen in jujube tree root zones tended to gradually decrease from top to bottom in the soil profile at different growth stages. The soil available nitrogen contents at different growth stages exceeded initial values. The mineralization degrees of salt water which influenced the available nitrogen were successively 3 g/L＞4 g/L＞2 g/L＞CK, wherein the salt water with mineralization degree of 3g/L brought largest influences to transformation and utilization of available nitrogen in jujube tree root zones; with regard to different growth stages, the available nitrogen content was high in the soil layer with depth of 0-20 cm in the jujube root zone, and the content was small in the soil layer with depth o 30-50 cm; during drip irrigation with the mineralization degree of over 3g/L, the nitrate nitrogen content in soil layers of the jujube tree root zone exceeded the content under fresh water irrigation treatment as a whole.

A kinetic model for biofilm growth inside non-PC emitters under reclaimed water drip irrigation

Emitter clogging is tightly related to the formation and growth of biofilms inside emitters applying reclaimed water. In order to control emitter clogging and achieve highly efficient drip irrigation (DI) system, understanding the kinetics of biofouling is important. In this paper, four types of non-pressure-compensating (non-PC) flat emitters and five types of non-PC cylindrical emitters were selected for reclaimed water DI experiment, and the growing processes of biofilms components (Solid particles, SD; Phospholipid fatty acid, PLFAs; Extracellular polymeric substances, EPS) inside emitter flow path were tested. The results showed that the entire growing processes of biofilm SD, PLFAs and EPS could all be divided in proper order, i.e., growing adaptive period, rapid growing period and dynamic stable period. To be specific, biofilms were adapting to the growing environment in the initial 408h, while their formation velocity was relatively slow. It was followed by the rapid growing period when the system accumulatively operated 408–1088h. Then biofilm growth and detachment tended to reach dynamic balance till 1224h. Therefore, based on the prototype of Logistic growing model, the paper established a kinetic model of biofilms growth (SD, PLFAs and EPS) after the comprehensive consideration of their growing response to emitter types, flow path geometrical parameters and lateral positions. The model was verified to present the biofilm growth process well (R2>0.85**, significant level a=0.01). On the other hand, another model was proposed to reflect the influential effects of biofilm components on emitter clogging degrees. When combining these two models together, the results showed that the emitter clogging controlling methods should be carried out in the appropriate time in case of more serious emitter clogging. The control point was the time when DI system operated 300h accumulatively or before emitter clogging degree reached 25%. The results in this paper could provide theoretical references to reveal DI emitter clogging mechanism and to establish a controlling strategy against emitter clogging.

Irrigation and fertigation scheduling under drip irrigation for maize crop in sandy soil

Abstract Field experiments was conducted to determine the best irrigation scheduling and the proper period for injecting fertilizers through drip irrigation water in a sandy soil to optimize maize yield and water productivity. Four irrigation levels (0.6, 0.8, 1.0 and 1.2) of the crop evapotranspiration and two fertigation periods (applying the recommended fertilizer dose in 60 and 80% of the irrigation time) were applied in a split-plot design, in addition to a control treatment which represented conventional irrigation and fertilization of maize in the studied area. The results showed that increasing the irrigation water amount and the fertilizer application period increased vegetative growth and yield. The highest grain yield and the lowest one were obtained under the treatment at 1.2 and of 0.6 crop evapotranspiration, respectively. The treatment at 0.8 crop evapotranspiration with fertilizer application in 80% of the irrigation time gave the highest water productivity (1.631 kg m−3) and saved 27% of the irrigation water compared to the control treatment. Therefore, this treatment is recommended to irrigate maize crops because of the water scarcity conditions of the studied area.

Effect of Insecticides on Celery Insects, 2014: Table 1.

Celery was transplanted in a sandy loam type soil on 4 Sep 2014 at the University of California’s South Coast Research and Extension Center. The plants were drip irrigated (water pH 7.2–7.5). Experimental plots were three beds wide (two rows per bed) on 40 in. centers by 40 ft long and separated by a 3-ft. buffer with four replicates of each treatment in an RCB design. The foliar insecticide spray applications were initiated on 30 Oct and continued through 11 Dec. The low input treatment …

Effect of Insecticides on Pepper Insects, 2015: Table 1

To determine the effect of insecticides on pepper insect control, seedlings were transplanted in a sandy loam type soil on 5 Jun at the University of California’s South Coast Research and Extension Center. Experimental plots were three rows wide (5-ft centers) by 20-ft long and separated by a 3-ft buffer. The pepper transplants were drip irrigated (water pH 7.2–7.5). Treatments were replicated four times in an RCB block design. A treatment list is shown in Table 1. The Radiant and Lannate plus Pounce treatments were applied as weekly foliar sprays …

Physiological and biochemical responses to the exogenous application of proline of tomato plants irrigated with saline water

In scope of crop salinity tolerance, an experiment was carried out in a field using saline water (6.57dSm−1) and subsurface drip irrigation (SDI) on two tomato cultivars (Solanum lycopersicum, cv. Rio Grande and Heinz-2274) in a salty clay soil. Exogenous application of proline was done by foliar spray at two concentrations: 10 and 20mgL−1, with a control (saline water without proline), during the flowering stage. Significant higher increases in proline and total soluble protein contents, glutamine synthetase (GS, EC6.3.1.2) activities and decreases in proline oxidase (l-proline: O2 Oxidoreductase, EC1.4.3.1) activities were detected in both tomato cultivars when irrigated with saline water (6.57dSm−1) and exogenously applied by the lower concentration of proline. Taking in consideration the obtained results, it was concluded that the foliar spray of low concentration of proline can increase the tolerance of both cultivars of tomato to salinity under field conditions.

Effect of Insecticides on Pepper Insects, 2014: Table 1

To determine the effect of insecticides on pepper insect control, seedlings were transplanted in a sandy loam type soil on 10 June at the University of California’s South Coast Research and Extension Center. Experimental plots were three rows in width (5-ft centers) by 40 ft in length and separated by a 3-ft buffer. The pepper transplants were drip irrigated (water pH 7.2–7.5). Treatments were replicated four times in an RCB block design. A treatment list is shown in Table 1. Treatments of Radiant, and Intrepid …

Effect of Insecticides on Celery Insects, 2013: Table 1

Celery was transplanted in a sandy loam type soil on 28 August 2013 at the University of California’s South Coast Research and Extension Center. The plants were drip irrigated (water pH 7.2–7.5). Experimental plots were 3 beds in width (2 rows per bed) on 40-inch centers by 40 ft in length and separated by a 3-ft buffer with four replicates of each treatment in RCB design. The foliar insecticide spray applications were initiated on 22 October and continued through 19 …

Effect of Insecticides on Tomato Insects, 2014: Table 1

“Bobcat” fresh market tomato seedlings were transplanted in a sandy loam type soil on 10 June 2014 at the University of California’s South Coast Research and Extension Center. Experimental plots were 3 rows wide (5-ft centers) by 40 ft long and separated by a 3-ft buffer. The tomato transplants were drip irrigated (water pH 7.2–7.5). Treatments were replicated four times in an RCB block design. Foliar applications …

English

According to limited water in arid regions and its sharp drop per capita, we have to maximize water use efficiency under the best system for saving water (drip irrigation). To achieve this goal, two field experiments were carried out during growing seasons 2013 and 2014, it was executed in research farm of national research center (NRC) in Nubaryia province, Egypt, to study the effect of new engineering method for irregular volumetric distribution ratios of compost under reduction of emission uniformity on yield and water use efficiency of peanut crop. Study factors were irregular volumetric distribution ratios of compost on four zones along lateral were [D1= (25%, 25%, 25%, 25% compost), D2= (20%, 20%, 25%, 35% compost), D3= (15%, 15%, 30%, 40 compost) and D4= (10%, 10%, 35%, 45% compost)] under reduction of emission uniformity (EU) and emitter discharge along lateral, [EU1= 90%, EU2 = 80%, and EU3 = 70%].to study the effect of new engineering method for irregular volumetric distribution ratios of compost under reduction of emission uniformity on yield and water use efficiency of peanut crop. The following parameters were studied to evaluate the effect of study factors on: (1) Application efficiency along lateral. (2) Water stress along lateral (3) Yield of peanut, (4) Irrigation water use efficiency of Peanut IWUE Peanut.

A vegetation reconstruction method to plant Sedum spectabile Boreau using drip-irrigation with saline water on a coastal saline soil in region around Bohai Gulf

Soil salinity and saline groundwater are major constraints to the cultivation of crops and landscape plants in coastal regions. With the rapid industrialization and urbanization in these areas, there is an urgent need to improve the landscape to meet the increasing demand of living environments for cities and districts. The aim of this study was to propose a method to plant Sedum spectabile Boreau, a common landscape flower plant, on a very heavy coastal saline soil using drip-irrigation with saline water in region around Bohai Gulf. The salinity levels of irrigation water were 0.8, 3.1, 4.7, 6.3a, nd 7.8 dS/m, respectively. The results showed that the revegetation method, which mainly included ‘ridge planting + saline water drip-irrigation’, was effective in planting Sedum spectabile Boreau for reclaiming coastal saline silt soil. An soil matric potential (SMP) higher above −5 kPa after transplanted and −10 kPa after growing season ended, and 6 mm of irrigation water can be used as indicators for Sedum spectabile Boreau drip-irrigation scheduling with 100 % survival rate when irrigated with saline water at <7.8 dS/m in initially saline soils with a gravel–sand layer after tillage. This method is combined with comprehensive utilization of the saline water, agronomic measures, collaborative repair of the soil and plants to offer new views and theoretical support for the protection and development of saline land in coastal regions.