Microirrigation Systems Research Articles

Studying the Parameters and Reliability of the System of Small Intensity Irrigation for Work in the Conditions of Mining Agriculture in Azerbaijan.

The article discusses the issues of scientific and theoretical justification for the use of automated irrigation in agriculture, that these systems can reduce the capital costs of their construction, as well as ensure the principle of "rain" and "drip irrigation" with daily water consumption of plants. There are optimal conditions for the growth and development of plants during their growing season. It is proved that the automated irrigation of agricultural crops establishes high yields and increased labor productivity. Therefore, the elements and devices of the used automatic machine require a reliable and uninterrupted operation. This is due to the fact that the problem is that the problem lies not only in technical reliability but also in economic efficiency. , including micro-irrigation systems. Reliability, performance, and performance. Initially, the existing irrigation technique, stationary irrigation system consisted of a large number of elements of the same type, necessary for conducting field cultural events.

Effect of underdrain design, media height and filtration velocity on the performance of microirrigation sand filters using reclaimed effluents

Sand filters are commonly used in microirrigation systems to prevent emitter clogging, especially when wastewater is used. However, little is known about the operating conditions required to guarantee a good filtration and a low energy consumption. For this reason, three sand filters with different drainage designs (collector arms, inserted domes and porous medium) using reclaimed effluents were analysed when operating with two sand media heights (0.20 and 0.30 m) and two filtration velocities (30 and 60 m h−1). Each one of these four different operating conditions (combination of two sand media heights and filtration velocities) was tested for 250 h. Filtered and backwashed volumes, energy consumption during filtration and backwashing, inlet and outlet filter pressures, and water quality parameters at filter inlet and outlet were recorded using a supervisory control and data acquisition system. Results showed that porous media underdrain design presented higher turbidity removal efficiencies for most of the tested conditions (38.53, 33.63 and 10.51% at 0.20 m/30 m h−1, 0.20 m/60 m h−1 and 0.30 m/60 m h−1, turbidity removal, with sand media height/filtration velocity, respectively) and dome underdrain only at 0.30 m/60 mh−1 (47.74%). Porous media underdrain also filtered more water volume per electrical energy unit (8.30 m3 kWh−1) than domes and arm collector underdrain (8.18 and 8.07 m3 kWh−1, respectively). In general, filtration velocities of 30 m h−1 showed higher turbidity removals and filtered more water volume per electrical energy unit than 60 m h−1. Media height did not show a clear effect, but smaller media heights did allow energy and material saving.

Impact of municipal wastewater reuse through micro-irrigation system on the incidence of coliforms in selected vegetable crops

The incidence of coliforms in soil and agricultural produce was evaluated in two vegetable crops, namely, cauliflower and eggplant, which were grown using wastewater for irrigation. Field experiment was conducted at Indian Agricultural Research Institute (IARI), New Delhi, India. In the field experiments to irrigate the crop, municipal wastewater was applied through drip system. The filtration of irrigation water was done through sand media, disk media and their combination. The laterals were placed at surface and subsurface of soil. All filtration processes significantly reduced total coliforms (12–20%) and E. coli (15–25%) populations when evaluated against untreated wastewater. The population dynamics of coliforms in soil profiles indicated that the maximum population of E. coli was estimated on the surface of soil profile when using surface drip, which decreased with soil depth under subsurface placement of drip lateral. After crop harvesting, E. coli in the soil reduced until 20 days after the cessation of irrigation and was highly correlated with soil moisture. E. coli and total coliforms availability were noticed on the surface and in the tissues of leaf and fruit, the coliform count is higher on the surface of plants under surface placement of drip lateral. The concentration of coliforms was lower with eggplant in comparison to cauliflower due to the smooth fruit surface of eggplant. Our study reveals the critical role of subsurface drip irrigation in reducing the load of coliform both in the soil and the crop produce ensuring safety of the consumers against health hazards. In another way protect the environment from wastewater disposal and reduce the burden on synthetic fertilizers as well as shrinking freshwater resources.

VERTICAL TURF FOR GREEN FAÇADES: A VERTICAL GREENERY MODULAR SYSTEM INTEGRATED TO THE BUILDING ENVELOPE

ABSTRACT Research has shown the environmental benefits of green envelopes, as well as performance in terms of energy efficiency. To date, there is no analysis of the economic sustainability of these systems, which has allowed the realization of a few, albeit very well known, examples. The research has identified a green modular system integrated into the building envelope, designed to facilitate installation and maintenance, with competitive performance compared to other existing solutions; a system that wants to improve performance and flexibility of vertical applications, experimented on buildings, on the market, and able to adapt, above all, to the needs of the building process. It is important to distinguish architectural aesthetic requirements from those of the building process; the former aim to have an authentic vertical garden, with different kinds of plants where nature dictates the rules, the latter aims to achieve the economic sustainability of vertical greenery systems. This paper provides an analysis of a technique based on the installation of plant bearing modular panels with turf on substructures also provided with a micro-irrigation system, which allows the construction of a modular coating, characterized by reduced thickness, that can also be integrated with other materials; installation is quick and simple, since the panel comes perfectly planted on site. In addition to that it allows, from a botanical point of view, resorting to types of grass selected with a view to climate, exposure, environmental adaptability, color and shape. A comparative analysis of this green façade is also presented compared to other existing case studies, from a constructive and managerial point of view, highlighting both its economic and architectural advantages.

A Modified Surface Energy Balance to Estimate Crop Transpiration and Soil Evaporation in Micro-Irrigated Orchards

A surface energy balance model was conceived to estimate crop transpiration and soil evaporation in orchards and vineyards where the floor is partially wetted by micro-irrigation systems. The proposed surface energy balance model for partial wetting (SEB-PW) builds upon previous multiple-layer modelling approaches to estimate the latent, sensible, and soil heat fluxes, while partitioning the total evapotranspiration ( E T ) into dry and wet soil evaporation ( λ E s o i l ) and crop transpiration ( T ). The model estimates the energy balance and flux resistances for the evaporation from dry and wet soil areas below the canopy, evaporation from dry and wet soil areas between plant rows, crop transpiration, and total crop E T . This article describes the model development, sensitivity analysis and a preliminary model evaluation. The evaluation shows that simulated hourly E T values have a good correlation with field measurements conducted with the surface renewal method and micro-lysimeter measurements in a micro-irrigated winegrape vineyard of Northern California for a range of fractional crop canopy cover conditions. Evaluation showed that hourly L E estimates had root mean square error ( R M S E ) of 58.6 W m−2, mean absolute error ( M A E ) of 35.6 W m−2, Nash-Sutcliffe coefficient ( C N S ) of 0.85, and index of agreement ( d a ) of 0.94. Daily soil evaporation ( E s ) estimations had R M S E of 0.30 mm d−1, M A E of 0.24 mm d−1, C N S of 0.87, and d a of 0.94. E s estimation had a coefficient of determination ( r 2 ) of 0.95, when compared with the micro-lysimeter measurements, which showed that E s can reach values from 28% to 46% of the total E T after an irrigation event. The proposed SEB-PW model can be used to estimate the effect and significance of soil evaporation from wet and dry soil areas on the total E T , and to inform water balance studies for optimizing irrigation management. Further evaluation is needed to test the model in other partially wetted orchards and to test the model performance during all growing seasons and for different environmental conditions.

Local head loss caused in connections used in micro-irrigation systems

ABSTRACT Information about local head loss caused by connections employed in micro-irrigation systems is hard to be found in literature. The objective of this research was to experimentally determine the local head losses in connections commonly used in micro-irrigation and propose mathematical models using the theorem of Buckingham. The methodology of tests was based on international standards. The tests were carried out under controlled inlet pressure, at 150 kPa, and five to ten units of each connection model were tested. The curves relating flow and head losses were drawn based on 15 flow conditions, obtained under increase and decrease of flow rate. For each condition, 30 points were collected resulting in a sample size of 900 points in each test. For each connection model evaluated, the following information was obtained: curves of local head loss as a function of flow rate and of local head loss coefficient (KL). The obtained values of KL ranged from 2.72 to 24.16, which become constant for Reynolds number higher than 10,000. The sensitivity of the coefficient related to a ratio of the internal sections in the connections was also verified. The flow exponents presented values close to the one applied by the Darcy-Weisbach equation (m = 2). The models developed for the connections presented a satisfactory performance.

Assessment of Field Water Uniformity Distribution in a Microirrigation System Using a SCADA System

Microirrigation is an efficient irrigation technique, although when wastewater is used the probability of operation problems such as emitter clogging increases. In most of microirrigation systems, control of irrigation performance is manual and sporadic, therefore clogging problems may not be detected at the right time. As it is easier to prevent emitter clogging if it is detected earlier, close monitoring of pressure and flow rates in microirrigation systems is an important way to achieve microirrigation system requirements and accomplish higher irrigation efficiencies. A supervisory control and data acquisition (SCADA) system was used to monitor and control the performance of three microirrigation subunits; each one with four laterals, 90 m long with 226 emitters. The SCADA system monitored the pressure and flow across the irrigation laterals, and distribution uniformity coefficients were determined in real time, as they are indexes commonly used for evaluating drip irrigation systems. Results were compared with those experimentally obtained, showing a good correlation; although the emitter position had an important effect on the computed values. This work shows that a SCADA system can be easily used to continuously assess the pressure and water distribution uniformity without carrying out time-consuming manual field assessments.

A low-cost, high-precision drip emitter suitable for low-pressure micro-irrigation systems

Potential low-cost micro-irrigation emitters appropriate for smallholder farmers in developing countries were the subject of a field experiment. Low-cost micro-irrigation technologies have been introduced with some success; however, further improvements are needed to increase adoption. The experiment evaluated three types of metal screw drip emitters (brass, zinc, and stainless steel), a conventional drip emitter, and a low-cost drip emitter (microtube). The effect of lateral flushing on emitter discharge and emitter uniformity was also evaluated. Emitter discharge, coefficient of variation (Cv), emission uniformity (EU), emitter blockage rates, and crop yield (Lactuca sativa ‘Toronto’) were the evaluation parameters. Screw emitter Cv ranged from 5 to 27%, and the conventional emitter and microtube emitter Cv were 9% and 29%, respectively. Blockage rates were significantly greater in the microtube, brass, and zinc emitters. Individual lettuce plant weight ranged from 0.676 to 0.912 kg/head for the three screw-based emitters, and 0.711 kg/head and 0.816 kg/head, respectively, for the microtube and conventional emitters. The stainless steel and conventional emitter performance were superior in all indices used to evaluate the emitters. Weekly flushing of laterals was found to be beneficial in optimizing emitter discharge and uniformity. Field evaluation demonstrated the potential use of metal-based screws as drip emitters.

Treated wastewater reuse in micro-irrigation: effect of shear stress on biofilm development kinetics and chemical precipitation

ABSTRACT Treated wastewater in micro-irrigation is a promising approach that could be used to decrease the pressure on good quality water resources. However, the clogging of such systems due to biofilm development and chemical precipitation constitute a constraint with the use of treated wastewater (TWW) and lead to lower irrigation system performance. The objective of this work is to study the development of biofilm and composition of fouling due to TWW under shear stresses of 0.7, 2.2 and 4.4 Pa detected along micro-irrigation systems. For this purpose, a Taylor-Couette reactor (TCR) was specifically calibrated for the cultivation of biofilm. The analysis of fouling composition samples (organic and inorganic) shows that biofilm tends to develop under the highest shear stress value (4.4 Pa). Precipitation of calcium carbonate in the form of calcite was observed in conjunction with biofilm growth using X-ray diffractometry (XRD) and thermogravimetric analysis (TGA). These results can be used to ascertain the origins of chemical and biological clogging of drippers and fouling of pipes related to reclaimed water- irrigation.

Performance and Evaluation of Drip Irrigation System, and Its Future Advantages

The drip irrigation system is a kind of micro-irrigation system that has the potential to salvage the water and other nutrients by entrance water to drip gradually to the main roots of plants and other plant parts, which is from on the soil surface or buried inside the soil surface. The main aim of drip irrigation is to place water directly into the main root zone and decrease the water vapor. The system Drip irrigation spreads water through a schematic shape of different tubes, emitters, pipes, and valves. Its depending on the designed how well it make, maintained, installed, and operated it is, a system drip irrigation can be more useful than other various types of drip irrigation systems, like as sprinkler irrigation or surface irrigation. The system drip irrigation is firstly introduced mainly to save water and step-up the water use efficiency in agriculture field. More ever, it also presents various other social and economic benefits to the society. In drip irrigation system water is utalized micro jet or by drop by drop, on the surface of soil or under the soil, at a lower rate than the infiltration of the soil. In our this research, deeply research works heed water management for system drip irrigation and its upcoming advantages has been discussed and reviewed so that a precise perception may be existence for the farmers and for futures. Keywords: Drip irrigation, dipper line, water, Fertigation system. DOI: 10.7176/JBAH/9-9-04 Publication date:May 31st 2019

Field Evaluation of Container Nursery Irrigation Systems: Part 2: Measuring Application Rates

Performance of sprinkler and microirrigation systems can be evaluated by measuring operating pressures, application rates, and uniformity of water application under nursery conditions. We discuss the measurement of application rates for overhead sprinkler systems. The application rate is defined as the average depth of water applied per unit time of system operation. For a sprinkler system, application rate is usually expressed in inches per hour.

Field Evaluation of Container Nursery Irrigation Systems: Part 1: Measuring Operating Pressures in the Irrigation System

Performance of sprinkler and microirrigation systems can be evaluated by measuring operating pressures, application rates, and uniformity of water application under nursery conditions. Knowledge of these factors is important to determine the causes of poor system performance. This publication will focus on operating pressure and will discuss application rates and uniformity in other publications.

Evaluation of drip irrigation system performance under local gravel media in laboratory

In drip irrigation water is applied to each plant separately in small, frequent and precise quantities through dripper emitters. It is the most advanced irrigation method with the highest application efficiency. The main objective of the present work was evaluation of drip irrigation system in laboratory and determination of concentration of suspended solids in the filtration media. In the micro-irrigation system the small openings can be easily clogged by suspended solids according to the level of total suspended solids (TSS) and plugging is caused which falls into three categories ( 100 ie slight, moderate and severe respectively). It was found that in case of using media filter, TSS value in water sample of media filter of Local Basalt was lower than Alabaster Misr Bank which was less than Ward El-Nile Zaffaranat at operating pressure of 20 to 60 kpa. Evaluation of the dripper's efficiency according to use appropriate filtration media for first filter Local Basalt at 20, 40 and 60 kPa emission uniformity EU was 94.73, 89.55 and 79.47 per cent ie excellent, good and fair value respectively; for second filter of Alabaster Misr Bank at 20, 40 and 60 kPa the EU was 95.84, 89.67 and 79.57 per cent ie excellent, good and fair respectively and for third filter of Ward El-Nile Zaffaran at 20, 40 and 60 kPa EU was 95.58, 87.56 and 68.56 per cent ie excellent, good and poor respectively. Accuracy of filtering media type with high efficiency for filtration the value was 79.3 and 76.9 per cent for Local Basalt and Alabaster Misr Bank but in the filter media of Ward El-Nile Zaffaran the removal efficiency was low (40.97%).

DOMIS:A Decision Support System for Design and Cost Estimation of Micro-Irrigation Systems

DOMIS:A Decision Support System for Design and Cost Estimation of Micro-Irrigation Systems

The contribution of smallholder agriculture to the nutrition of rural households in a semi-arid environment in South Africa

The contribution of own food production to the nutrition of households in two neighbouring, rural, semi-arid settlements was investigated. A survey of a 10% probability sample (n=131) of households in Sekuruwe and Ga-Molekane in the Mokgalakwena Local Municipality, Waterberg District Municipality, Limpopo Province, South Africa, conducted in 2001, provided data on household composition, income (cash and kind), poverty status, expenditure and agriculture, including a detailed account of the types and quantities of food that were purchased during the month preceding the date of the interview. For each household the food obtained from the different types of agriculture they practised was quantified. Protein, iron and Vitamins A and C were selected as indicators to assess the contribution of purchased and own produced food to the food intake of households. Food composition tables were used to estimate the nutrient content of the different foods. To assess the contribution of irrigated home gardening to food intake of households, Drum & Drip micro-irrigation systems which enabled irrigated vegetable production on an area of 36 m2 were installed on the residential sites of 10 volunteer households in the study area. The results confirmed that income is the most important determinant of household food security in rural South Africa. However, food obtained from various types of dry-land agriculture contributed significantly to household nutrition and without farming the food security of households would be reduced, especially among the ultra-poor. Small-scale irrigated vegetable production was shown to have the potential to substantially raise the amount of the Vitamins A and C available to households but did not address the lack of protein in the diet of ultra-poor households and the lack of iron in the diet of all households.Keywords: household food security, nutrition, poverty, rural agriculture, semi-arid, dry-land farming, irrigated home gardening, micro-nutrients, protein, iron, Vitamin A, Vitamin C

Production of Thuja (T. standishii x T. plicata) Using an Automated Micro-Irrigation System and Routine Leaching Fraction Testing in a Container Nursery1

Abstract A web-based, container irrigation scheduling program (CIRRIG) based on routine Leaching Fraction (LF=drainage/applied) testing and real-time weather monitoring was evaluated for its effect on plant growth and water use of Thuja (T. standishii x T. plicata) ‘Green Giant' in #15 [43 cm (17 inch)] containers in a commercial nursery in Florida. Independently-controlled irrigation zones each containing 830 plants were irrigated automatically with CIRRIG or with the nursery's traditional irrigation practice of a fixed daily rate. After 6 months, CIRRIG reduced the total volume of water applied by 51% [490 vs. 990 L/plant (129 vs. 262 gal/plant) but reduced growth in plant height and width by 15% and 10%, respectively. Routine LF testing indicated that the target LF of 25% was likely too low for the coarse pine bark substrate and spray-stake irrigation system. In light of stricter consumptive use permitting of water by governmental agencies, technologies such as CIRRIG may allow nurseries to produce more plants with less water. Index words: CIRRIG, evapotranspiration, growth, landscape plant, programmable logic controller, water use Species used in this study: Thuja Green Giant [Thuja (T. standishii x T. plicata) ‘Green Giant']

Response of micro-irrigation systems on growth, yield and WUE of Pomegranate (Punica granatum L.) in semi-arid regions of India

The effects of various micro-irrigation systems on some parameters of Pomegranate (Punica granatum L. cv. Bhagwa) i.e. physiological, yield, fruit qualities, root density, water use and water use efficiency parameters studied in the field experiments. Six types of micro-irrigation treatments with four replications were applied: 4-subsurface and 2-surface micro-irrigation were presented along with the 1-inline lateral at dripper spacing 30 cm, 2-inline laterals at drippers spacing 30 x 30 cm, 2-inline laterals at drippers spacing 40 x 40 cm; 2-inline laterals at drippers spacing 50 x 50 cm; 1-online lateral with 2-drippers (2D) and 2-online laterals with 4-drippers (4D), respectively. Maximum plant height, steam diameter, leaf area index, flowers, nutrient status and yield was recorded in subsurface drip irrigation system (SDI) with 2-inline laterals (30 x 30 cm) followed by (40 x 40 cm), (50 x 50 cm), surface drip irrigation (DI) with 2-laterals and 4drippers, 1-inline lateral at dripper spacing 30 cm and 1-online lateral with 2drippers. Soil moisture withholding was also higher in the SDI with double inline laterals (30 x 30 cm). The total average quantities of water used ranged from 2520.20 to 8340.60 Lbahar−1 t−1 and water use efficiency was found to be ranged from 1.98 to 4.01 kg m-3 in micro-irrigation systems. The biophysical advantages are low canopy humidity and fewer diseases and weeds. The results showed that 30 x 30 cm inline double lateral enhanced the flowering intensity, yield, root density and water use efficiency of pomegranate.

Composite clogging characteristics of emitters in drip irrigation systems

This study investigated the characteristics of emitter clogging substance in 16 kinds of drip irrigation emitters using 3 kinds of water sources that could typically induce composite clogging in the Yellow River irrigation area. The research results indicate that there was remarkable randomness in the behavior of composite clogging substances in a single emitter, and peak randomness ( $$\Delta F_{Q}^{t}$$ ) values were 19.5–20.8%, 20.5–22.4% and 25.9–28.2% higher than that with physical, chemical and biological clogging, respectively. Clogging in a single emitter also exhibited recoverability ( $$R_{Q}^{{{\text{CD}}}}$$ ) which would be lost when the clogging degree reached 60–75%, and recoverability ( $$R_{Q}^{{{\text{CD}}}}$$ ) showed the opposite variation rule to randomness ( $$\Delta F_{Q}^{t}$$ ). Though clogging in a single emitter was associated with certain randomness and recoverability, the overall variation of the micro-irrigation system's average discharge variation ratio (Dra) and Christiansen’s uniformity (CU) was not affected. Instead, the two showed relatively consistent dynamic variation of mild fluctuation followed by acute descending. The fluctuation trend during the earlier stage lasted from 128 to 660 h, and descending branch slopes of Dra and CU during the later stage were 0.09–0.12 and 0.13–0.21, respectively. In terms of various types of emitters, $$\Delta F_{Q}^{t}$$ generally demonstrated dynamic variation for a tape emitter (highest), a single-side labyrinth emitter (slightly lower), a cylindrical emitter (even lower) and a flat emitter (lowest). However, the dynamic variation of $$R_{Q}^{{{\text{CD}}}}$$ , Dra and CU were inverse. As far as various water sources were concerned, mixing water had the highest $$\Delta F_{Q}^{t}$$ , followed by Yellow River water, and surface lake water had the lowest $$\Delta F_{Q}^{t}$$ , while variation characteristics of $$R_{Q}^{{{\text{CD}}}}$$ , Dra and CU among the three water sources were inverse. The present study could provide reference for revealing the characteristics of composite clogging in emitters, thus constructing effective clogging control methods.

Methodology to Evaluate Dripper Sensitivity to Clogging due to Solid Particles: An Assessment.

Emitter clogging is a major problem in microirrigation systems, which may result from the isolated or combined effects of physical, chemical, and biological agents. Clogging caused by suspended solid particles is the most common plugging form of emitters. Water quality and emitter geometry are key aspects in clogging processes. Any suitable test procedure to assess the sensitivity of drippers to clogging should take into account the predominant factors that influence clogging and must reproduce the field conditions. This research set out to assess the performance and suitability of a laboratory clogging test procedure in order to validate a methodology and to provide scientific results that may support the standardization of a clogging test method. The evaluated methodology has been used by the IRSTEA laboratory since 1974 (Platform of Research and experiment on Science and Technology for Irrigation - PReSTI, formerly LERMI) and its contents are currently being discussed by the ISO TC23/SC18 committee. The aim is to define a standardized testing protocol to evaluate the sensitivity of emitters to clogging due to solid particles. Replications analyzing the clogging resistance of four models of emitting pipes were carried out in a laboratory. The clogging test procedure enabled an accurate assessment of the combinations of concentration and size of particles that caused clogging in each model of dripper. However, a significant variability in degree of clogging was identified when the results of replications for each model of dripper were compared. Several requirements, concerns, and improvements related to the clogging test protocol were discussed.

Evolving high altitude livelihoods and climate change: a study from Rasuwa District, Nepal

This study examined local people’s perception of climate change and its impacts on their livelihoods, and identified key opportunities and threats arising in four Village Development Committees in the high mountains of Rasuwa District, Nepal. The local people are still heavily dependent on agriculture and livestock for their food security and livelihoods, despite the involvement of a significant proportion of households in non-agricultural income-generating activities, such as tourist services and labour work in other areas (outmigration). In agriculture, farmers mainly cultivate traditional food crops such as millets, buckwheat, local beans, and barley. They also cultivate rice, potato, and vegetables. Agriculture is mainly rainfed with a few exceptions of micro-irrigation systems fed by springs and snow-melt water. The impacts of climate change are mixed to date: changes in patterns of snowfall and snowmelt, rainfall, and temperatures are having both positive and negative impacts. Households are adapting to this changing climate through changes in their cropping patterns, integration of livestock with agriculture, and adoption of non-farm income activities. There are also new opportunities coming up at the study sites such as new markets for vegetables, traditional crops, and livestock.