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Journal articles on the topic 'Compact Irrigation'
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1
Delalieux, S., B. Delauré, L. Tits, M. Boonen, A. Sima, and P.-J. Baeck. "High resolution strawberry field monitoring using the compact hyperspectral imaging solution COSI." Advances in Animal Biosciences 8, no. 2 (2017): 156–61. http://dx.doi.org/10.1017/s2040470017001297.
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In strawberry production, a balanced and accurate irrigation schedule is essential, because of the high sensitivity of strawberry plants to water deficits and waterlogging. The optimal irrigation management strategy can, however, only be obtained by an accurate crop monitoring system. To replace the current visual inspection methods, which are subjective, time consuming and labour-intensive, the performance of the COmpact hyperSpectral Imaging system (COSI) mounted on an RPAS (Remotely Piloted Aircraft System) was evaluated. The study, focusing on different irrigation treatments in strawberry cultivation, unraveled the potential of the COSI system, to monitor field variations, even at small scale. Growth inhibition and differences in plant physiology due to water deficit could be detected. As such, the COSI system has shown potential for steering irrigation management decisions in strawberry cultivation.
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Kim, Minyoung, Hyejin Lee, Minkyeong Kim, et al. "Wastewater retreatment and reuse system for agricultural irrigation in rural villages." Water Science and Technology 70, no. 12 (2014): 1961–68. http://dx.doi.org/10.2166/wst.2014.430.
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Climate changes and continuous population growth increase water demands that will not be met by traditional water resources, like surface and ground water. To handle increased water demand, treated municipal wastewater is offered to farmers for agricultural irrigation. This study aimed to enhance the effluent quality from worn-out sewage treatment facilities in rural villages, retreat effluent to meet water quality criteria for irrigation, and assess any health-related and environmental impacts from using retreated wastewater irrigation on crops and in soil. We developed the compact wastewater retreatment and reuse system (WRRS), equipped with filters, ultraviolet light, and bubble elements. A pilot greenhouse experiment was conducted to evaluate lettuce growth patterns and quantify the heavy metal concentration and pathogenic microorganisms on lettuce and in soil after irrigating with tap water, treated wastewater, and WRRS retreated wastewater. The purification performance of each WRRS component was also assessed. The study findings revealed that existing worn-out sewage treatment facilities in rural villages could meet the water quality criteria for treated effluent and also reuse retreated wastewater for crop growth and other miscellaneous agricultural purposes.
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Niu, Genhua, Minzi Wang, Denise Rodriguez, and Donglin Zhang. "Response of Zinnia Plants to Saline Water Irrigation." HortScience 47, no. 6 (2012): 793–97. http://dx.doi.org/10.21273/hortsci.47.6.793.
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As high-quality water supply becomes limited in many regions of the world, alternative water sources are being used for irrigating urban landscapes. Therefore, salt-tolerant landscape plants are needed. Two greenhouse experiments were conducted to screen the salt tolerance of Zinnia marylandica (‘Zahara Coral Rose’, ‘Zahara Fire’, ‘Zahara Scarlet’, ‘Zahara Starlight’, ‘Zahara White’, and ‘Zahara Yellow’) and Z. maritima ‘Solcito’. In Expt. 1, plants were subirrigated with nutrient or saline solutions at electrical conductivity (EC) at 1.4 (base nutrient solution, control), 3.0, 4.2, 6.0, or 8.2 dS·m−1 for 4 weeks, whereas in Expt. 2, plants were surface-irrigated with the same nutrient or saline solutions for 4 weeks. In Expt. 1, all plants, regardless of cultivar, died by the end of the treatment at EC 6.0 and EC 8.2 as a result of high salinity in the root zone. Plants became shorter and more compact as EC of irrigation water increased. Shoot dry weight of all cultivars in EC 4.2 was reduced by 50% to 56% compared with that of the control. Shoot Na+ and Cl– accumulated excessively as salinity increased in the irrigation water, whereas Ca2+, Mg2+, and K+ did not change substantially. In Expt. 2, mortality varied with cultivar and treatment. Similar to Expt. 1, growth reduction resulting from elevated salinity across cultivars was found. Therefore, it is concluded that zinnia cultivars used in this study are sensitive to salinity and should not be planted in areas with high soil salinity or when alternative waters with high salinity may be used for irrigation.
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Schütze, N., M. de Paly, and U. Shamir. "Novel simulation-based algorithms for optimal open-loop and closed-loop scheduling of deficit irrigation systems." Journal of Hydroinformatics 14, no. 1 (2011): 136–51. http://dx.doi.org/10.2166/hydro.2011.073.
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The scarcity of water compared with the abundance of land constitutes the main drawback within agricultural production. Besides the improvement of irrigation techniques a task of primary importance is solving the problem of intra-seasonal irrigation scheduling under limited seasonal water supply. An efficient scheduling algorithm has to take into account the crops' response to water stress at different stages throughout the growing season. Furthermore, for large-scale planning tools compact presentations of the relationship between irrigation practices and grain yield, such as crop water production functions, are often used which also rely on an optimal scheduling of the considered irrigation systems. In this study, two new optimization algorithms for single-crop intra-seasonal scheduling of deficit irrigation systems are introduced which are able to operate with general crop growth simulation models. First, a tailored evolutionary optimization technique (EA) searches for optimal schedules over a whole growing season within an open-loop optimization framework. Second, a neuro-dynamic programming technique (NDP) is used for determining optimal irrigation policy. In this paper, different management schemes are considered and crop-yield functions generated with both the EA and the NDP optimization algorithms compared.
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Holt, Nathan, Rajendra P. Sishodia, Sanjay Shukla, and Kira M. Hansen. "Improved Water and Economic Sustainability with Low-Input Compact Bed Plasticulture and Precision Irrigation." Journal of Irrigation and Drainage Engineering 145, no. 7 (2019): 04019013. http://dx.doi.org/10.1061/(asce)ir.1943-4774.0001397.
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Scagel, Carolyn F., Guihong Bi, Leslie H. Fuchigami, and Richard P. Regan. "Effects of Irrigation Frequency and Nitrogen Fertilizer Rate on Water Stress, Nitrogen Uptake, and Plant Growth of Container-grown Rhododendron." HortScience 46, no. 12 (2011): 1598–603. http://dx.doi.org/10.21273/hortsci.46.12.1598.
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The influence of irrigation frequency (same amount of water per day given at different times) and nitrogen (N) fertilizer rate on water stress [stomatal conductance (gS)], N uptake, and growth (biomass) of container-grown evergreen Rhododendron ‘P.J.M. Compact’ and ‘English Roseum’ and deciduous Rhododendron ‘Gibraltar’ was evaluated. Both N deficiency and high N rate increased water stress. Water stress was greatest in plants fertilized with the highest N rate and gS of plants grown with the higher N rates changed more in response to water deficits resulting from irrigation treatments and seasonal climatic changes. Watering plants more frequently decreased water stress of plants fertilized with higher N rates and altering irrigation frequency had little impact on alleviating water stress of N-deficient plants. Increasing irrigation frequency decreased N uptake efficiency (N uptake per gram N applied), increased N use efficiency (growth per gram N uptake) and altered biomass allocation with little influence on total plant biomass. Response of biomass allocation to N rates was similar among cultivars and response of biomass allocation to irrigation frequency varied among cultivars. Altering irrigation frequency changed either the availability of N in the growing substrate or the ability of roots to absorb N. Our results indicate that transitory increases in plant water stress can alter N uptake, N use, and plant form without detectable changes in total plant biomass.
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Prasad, Nadipuram R., Satish J. Ranade, and Phuc Huu Nguyen. "Low-head hydropower energy resource harvesting: analysis and design of a Venturi turbine." Science and Technology Development Journal 18, no. 3 (2015): 102–10. http://dx.doi.org/10.32508/stdj.v18i3.891.
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The paper provides a low-head hydropower energy resource harvester (HyPER) design of 4-blade impeller with a fixed pitch blade angle. Based on a previous site evaluation and maximum power potential estimated without any modifications to the irrigation structure, the proposed objective of exploiting the estimated power will be met from harvester prototypes with portable, compact modular design. This makes assembly easy, uses off-the-shelf components to produce power. Calculations were carried out for designing guidevanes, Venturi tube, impeller blades and Computational Fluid Dynamics (CFD) software then is used in verifying the design. Designed as a self-supporting structure, the configuration offers a scalable hydropower generating system suitable for low-head drops along irrigation canals.
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Scagel, Carolyn F., Guihong Bi, Leslie H. Fuchigami, and Richard P. Regan. "Irrigation Frequency Alters Nutrient Uptake in Container-grown Rhododendron Plants Grown with Different Rates of Nitrogen." HortScience 47, no. 2 (2012): 189–97. http://dx.doi.org/10.21273/hortsci.47.2.189.
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The influence of irrigation frequency (same amount of water per day given at different times) on nutrient uptake of container-grown evergreen Rhododendron ‘P.J.M. Compact’ (PJM) and ‘English Roseum’ (ER) and deciduous Rhododendron ‘Gibraltar’ (AZ) grown with different rates of nitrogen (N) fertilizer was evaluated. Increased N application rate increased nutrient uptake and plant dry biomass. Irrigation frequency did not significantly influence total plant dry biomass; however, more frequent irrigation decreased net uptake of several nutrients including phosphorus (P), boron (B), and manganese (Mn) uptake in all cultivars; potassium (K), copper (Cu), and zinc (Zn) uptake in AZ and ER; sulfur (S) uptake in ER and PJM; and iron (Fe) uptake in AZ. Additionally, more frequent irrigation of evergreen cultivars increased calcium (Ca) uptake. Covariate analyses were used to compare nutrient uptake among cultivars and irrigation treatments after accounting for the variability in nutrient uptake attributable to differences in biomass and N uptake. For most nutrients, the influence of irrigation frequency on uptake was partially attributable to differences in biomass and N uptake. After accounting for the variability in nutrient uptake associated with biomass or N uptake, increased irrigation frequency decreased P, S, B, Cu, and Mn uptake only in ER and increased Ca uptake in the two evergreen cultivars. Differences in nutrient uptake among cultivars in response to irrigation treatments were related to water and N availability during production and their combined influence on water stress, nutrient uptake, and biomass partitioning. Estimates of nutrient demand and uptake efficiency using nutrient concentrations and ratios are discussed in relation to nutrient management differences for different cultivars and irrigation treatments.
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Koniarski, Michał, and Bożena Matysiak. "Effect of regulated deficit irrigation on growth, flowering and physiological responses of potted Syringa meyeri ‘Palibin’." Acta Agrobotanica 66, no. 4 (2014): 73–80. http://dx.doi.org/10.5586/aa.2013.053.
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<p>The aim of this study was to analyze the physiological and morphological response of <em>Syringa meyeri </em>‘Palibin’ to different levels of irrigation and to evaluate regulated deficit irrigation (RDI) as a possible technique for saving water in nursery production and promoting of flowering. Plants were grown in 3 liter containers in an unheated greenhouse and were subjected to six irrigation treatments for 18 weeks from the be- ginning of June to mid-October 2011. A drip irrigation system was used. Irrigation treatments were established on the basis of evapotranspiration (ETp). Three constant irrigation treatments were used: 1) 1 ETp; 2) 0.75 ETp; 3) 0.5 ETp, while the other three with irrigation varying between phases were as follows: 4) 1–0.5–1; 5) 1–0.25–1; and 6) 0.5–1–0.5 ETp. The 0.75 ETp and 0.5 ETp irrigation regimes adversely affected the growth and visual quality index of plants as well as they resulted in reduced leaf conductance, transpiration, maximum quantum efficiency of photosystem II (Fv/Fm) and CCI (chlorophyll content index). Plants grown under the 1–0.5–1 ETp regime had the same morphological parameters as plants grown under the 0.5 ETp treatment. A further reduction of water quantity supplied to plants in the 1–0.25–1 ETp regime resulted in further deterioration of the visual quality index of plants. In this study, the quality index of plants exposed to 0.5–1–0.5 ETp was similar to control plants (1 ETp). These plants were lower, more compact, and had smaller leaves than control plants. The irrigation regimes imposed in this study had no significant effect on the number of floral buds formed in relation to the control regime, except for 1–0.25–1 ETp where this number decreased.</p>
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HICKLENTON, PETER R., and K. B. McRAE. "MINERAL STATUS AND GROWTH OF CONTAINERIZED COMPACT ANDORRA JUNIPER UNDER DIFFERENT IRRIGATION AND FERTILIZER REGIMENS." Canadian Journal of Plant Science 69, no. 4 (1989): 1295–300. http://dx.doi.org/10.4141/cjps89-157.
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Juniperus horizontalis ’Plumosa Compacta’ were grown in 3.8-L containers to compare the factorial effects of irrigation (top vs. capillary) and controlled release fertilizer placement (incorporated vs. surface-applied) on shoot nutrient content and growth. These treatments were compared with a liquid fertilized control. Shoot N contents on 30 June (31 d after potting) were highest in plants which were top-irrigated and supplied with incorporated Nutricote, but were lowest in these plants at the end of the season (28 Sept.). Top-irrigated, Nutricote-incorporated, and liquid-fertilized plants showed the highest shoot K contents on 30 June. Lowest shoot K occurred in the top-irrigated, Nutricote-incorporated treatment on 28 Sept. In comparison with N or K, shoot P showed much less variation over the growing season. Incremental branch growth was less when fertilizer was surface-applied than when it was incorporated, but end-of-season shoot dry weights were similar in all plants except those which were top irrigated and supplied with incorporated Nutricote. This treatment produced the highest end-of-season shoot dry weight and best overall growth. Seasonal growth was positively correlated with early season (30 June) shoot N and K contents.Key words: Controlled release fertilizer, Nutricote, irrigation, Juniper
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Rathier, Thomas M., and Charles R. Frink. "Nitrate in Runoff Water from Container Grown Juniper and Alberta Spruce Under Different Irrigation and N Fertilization Regimes." Journal of Environmental Horticulture 7, no. 1 (1989): 32–35. http://dx.doi.org/10.24266/0738-2898-7.1.32.
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Abstract Juniperus horizontalis Moench ‘Plumosa Compacta Youngstown’ (compact Andorra juniper) and Picea glauca Moench (Voss) ‘Conica’ (dwarf Alberta spruce) were grown for one season in 2.2 1 (#1) nursery containers in a potting medium containing composted hardwood bark, sphagnum peat moss and sand (1:1:1 by vol). The containers were placed over lysimeters permitting continuous collection and measurement of water passing through and around the containers. Slow release or soluble N was applied at an annual rate of 1.6 g of N per pot. Containers were irrigated by either trickle or overhead methods and water volumes were recorded. Subsamples of leachate were collected and analyzed for nitrate. Much less nitrate was leached by the trickle than by the overhead irrigation. Although slow release N sources lost considerably less nitrate in runoff water, there is still sufficient nitrate lost by these sources to pollute ground water unless annual fertilizer needs are supplied by split applications. Depending on sources, 58–80% of the N applied as slow release fertilizers was not recovered in either the plant or runoff water.
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Scagel, Carolyn F., Guihong Bi, David R. Bryla, Leslie H. Fuchigami, and Richard P. Regan. "Irrigation Frequency during Container Production Alters Rhododendron Growth, Nutrient Uptake, and Flowering after Transplanting into a Landscape." HortScience 49, no. 7 (2014): 955–60. http://dx.doi.org/10.21273/hortsci.49.7.955.
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One deciduous cultivar of Rhododendron L., Gibraltar (AZ), and two evergreen cultivars, P.J.M. Compact (PJM) and English Roseum (ER), were grown in containers for 1 year to determine the effects of irrigation frequency during container production on plant performance the next spring when the plants were transplanted into the landscape. While in the containers, each cultivar was irrigated once or twice daily, using the same amount of water per day, and fertilized with complete nutrient solutions containing 0, 35, 70, or 140 mg·L−1 nitrogen (N). Three months after transplanting into the landscape, nutrient uptake, growth, and flowering were evaluated. In general, the effects of irrigation frequency in containers on performance in the landscape differed between the deciduous cultivar and the evergreen cultivars. In AZ, less frequent irrigation in containers had a pre-conditioning effect that resulted in greater vegetative growth in the landscape but less reproductive growth. In contrast, less frequent irrigation reduced vegetative growth of evergreen cultivars in the landscape and improved flowering. Different growth responses to irrigation frequency between deciduous and evergreen cultivars appeared to be related to differences in timing of nutrient uptake and mobilization. In the deciduous cultivar, less frequent irrigation increased nutrient reserves and improved the ability of the plants to absorb and use nutrients after transplanting, but in the evergreen cultivars, it generally decreased nutrient uptake after transplanting. Less frequent irrigation also altered plant attributes that are important to consumers, including developing a sparser canopy in ER and a fuller canopy in PJM, and producing more but smaller inflorescences in both cultivars. Landscape performance was related to plant nutrition in containers; however, irrigation frequency in containers disrupted relationships between nutrition and performance in all three cultivars. Our results indicate that irrigation frequency during container production of Rhododendron results in a tradeoff between vegetative and reproductive growth the next spring when the plants are in the landscape.
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Chen, Huifang, Yanfang Liu, Junying Chen, et al. "The Clogging Rules of Ceramic Emitter in Irrigation Using Saline Water with Different EC." Agronomy 9, no. 8 (2019): 436. http://dx.doi.org/10.3390/agronomy9080436.
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Infiltration irrigation with saline water is a more effective method than drip irrigation to alleviate water scarcity worldwide, but so far, no report has discussed the clogging rules of ceramic emitters, a major component of infiltration irrigation system. To explore the clogging mechanism of ceramic emitter in saline water infiltration irrigation system, we used four kinds of saline water sources with electrical conductivity (EC) of 0.18, 1.74, 3.78, and 7.74 ds/m, respectively. In addition, we specifically investigated the law of discharge ratio variation (Dra) of ceramic emitters, as well as the composition and growth process of clogging substance. The results indicated that the Dra of ceramic emitters decreased in the process of saline water irrigation, and the higher the EC, the more obvious the decrease. The calcium carbonate (CaCO3) was the main component of the clogging substance in the inner wall of ceramic emitters. The clogging part was a layer on the inner wall of the emitters rather than the pores in the walls, and the clogging did not occur suddenly. Instead, it was caused by the long–term accumulation of the clogging substance. Moreover, with the increase of EC, the flocculation between the clogging particles in the water was enhanced and thus promoted the formation of stable and compact aggregates, which fundamentally led to the clogging acceleration of ceramic emitters. This clogging mechanism of ceramic emitters can provide some theoretical reference for the establishment of anti-clogging strategy.
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Tong, Jingyang, Shujun Wang, Zhonghu He, and Yan Zhang. "Effects of Reduced Nitrogen Fertilization and Irrigation on Structure and Physicochemical Properties of Starch in Two Bread Wheat Cultivars." Agriculture 11, no. 1 (2021): 26. http://dx.doi.org/10.3390/agriculture11010026.
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Nitrogen (N) fertilization and irrigation are significant agronomic factors affecting wheat production, but little information is available on the effects of reduced N fertilization and irrigation on internal starch structure and physicochemical properties associated with the quality of wheat-based foods. In this study, reduced N fertilization and irrigation were separately applied to investigate their effects on composition and morphological changes, crystalline and external region structure features, swelling power, and gelatinization characteristics of starch granules in bread wheat, with a high N-use-efficiency and water-saving wheat cultivar Zhongmai 175 and a widely grown cultivar Jingdong 17. Compared with a non-N control, reduced N fertilization did not change the crystallinity type and short-range ordered degree of starch; however, it significantly increased relative crystallinity, swelling power and gelatinization enthalpy, whereas amylose content and transition temperatures were decreased. Under reduced irrigation, more small starch granules with compact arrangements appeared in comparison with non-water control. Relative crystallinity, swelling power and gelatinization enthalpy of starch were increased, whereas short-range ordered degree and transition temperatures were decreased. Moreover, the starch of the two cultivars appeared to differ in response to both the N and water treatments. The findings indicated that reduced N fertilization or irrigation markedly influenced the structure and physicochemical characteristics of wheat starch, providing important information for developing elite cultivars with high N and water use efficiency and outstanding starch quality.
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Dai, Jixiang, Yi Li, Hongbo Ruan, et al. "Fiber Optical Hydrogen Sensor Based on WO3-Pd2Pt-Pt Nanocomposite Films." Nanomaterials 11, no. 1 (2021): 128. http://dx.doi.org/10.3390/nano11010128.
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In this paper, WO3-Pd2Pt-Pt nanocomposite films were deposited on a single mode fiber as the hydrogen sensing material, which changes its reflectivity under different hydrogen concentration. The reflectivity variation was probed and converted to an electric signal by a pair of balanced InGaAs photoelectric detectors. In addition, the performance of the WO3-Pd2Pt-Pt composite film was investigated under different optical powers, and the irrigating power was optimized at 5 mW. With the irrigation of this optical power, the hydrogen sensitive film exhibits quick response toward 100 ppm hydrogen in air atmosphere at a room temperature of 25 °C. The experimental results demonstrate a high resolution at 5 parts per million (ppm) within a wide range from 100 to 5000 ppm in air. This simple and compact sensing system can detect hydrogen concentrations far below the explosion limit and provide early alert for hydrogen leakage, showing great potential in hydrogen-related applications.
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Dai, Jixiang, Yi Li, Hongbo Ruan, et al. "Fiber Optical Hydrogen Sensor Based on WO3-Pd2Pt-Pt Nanocomposite Films." Nanomaterials 11, no. 1 (2021): 128. http://dx.doi.org/10.3390/nano11010128.
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In this paper, WO3-Pd2Pt-Pt nanocomposite films were deposited on a single mode fiber as the hydrogen sensing material, which changes its reflectivity under different hydrogen concentration. The reflectivity variation was probed and converted to an electric signal by a pair of balanced InGaAs photoelectric detectors. In addition, the performance of the WO3-Pd2Pt-Pt composite film was investigated under different optical powers, and the irrigating power was optimized at 5 mW. With the irrigation of this optical power, the hydrogen sensitive film exhibits quick response toward 100 ppm hydrogen in air atmosphere at a room temperature of 25 °C. The experimental results demonstrate a high resolution at 5 parts per million (ppm) within a wide range from 100 to 5000 ppm in air. This simple and compact sensing system can detect hydrogen concentrations far below the explosion limit and provide early alert for hydrogen leakage, showing great potential in hydrogen-related applications.
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Palliotti, Alberto, Sergio Tombesi, Tommaso Frioni, et al. "Morpho-structural and physiological response of container-grown Sangiovese and Montepulciano cvv. (Vitis vinifera) to re-watering after a pre-veraison limiting water deficit." Functional Plant Biology 41, no. 6 (2014): 634. http://dx.doi.org/10.1071/fp13271.
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A better physiological and productive performance of cv. Montepulciano versus cv. Sangiovese under well-watered conditions has been recently assessed. The objective of this study was to verify that this behaviour is maintained when a pre-veraison deficit irrigation (vines held at 40% pot capacity from fruit-set to veraison) followed by re-watering (pot capacity reported at 90%). Single leaf assimilation rate and stomatal conductance, diurnal and seasonal whole-canopy net CO2 exchange (NCER) and water use efficiency were always higher in Sangiovese under deficit irrigation. Due to water shortage Montepulciano displayed a more compact growing habit due to decreased shoot and internode length. Sangiovese showed excellent recovery upon re-watering as NCER resulted to be higher than the pre-stress period; however, this might also relate to early and severe basal leaf yellowing and shedding. Early deficit irrigation affected xylem characteristics of Montepulciano more than in Sangiovese; vessel density increased (37 vs 29%, respectively, compared with well-watered vines) and the hydraulic conductance decreased more (–13 vs –3% respectively) compared with well-watered vines. Yield components and technological maturity were similar in the two cultivars, whereas Montepulciano grapes had lower anthocyanins and phenolics. Higher physiological and productive efficiency under non-limiting water conditions showed by Montepulciano compared with Sangiovese was basically reversed when both cultivars were subjected to an early deficit irrigation.
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Treder, Jadwiga, and Joanna Nowak. "The effect of irrigation frequency on growth, flowering and stomatal conductance of osteospermum 'Denebola' and New Guinea impatiens 'Timor' grown on ebb·and-flow benches." Acta Agrobotanica 54, no. 2 (2013): 59–68. http://dx.doi.org/10.5586/aa.2001.023.
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The response of osteospermum 'Denebola' and New Guinea impatiens 'Timor' grown on ebb-and-flow benches to different water potential of growing medium applied during whole growing period was investigated by measuring plant growth parameters and stomatal conductance (g<sub>S</sub>). After cutting establishment, four different irrigation treatments based on soil water potential were applied to osteospermum: at -0,5 , -3,0 , -10,0 , -20 kPa. In the case of impatiens the last water treatment was omitted. Plants were evaluated when they reach one ofthe three growth stages: lateral shoots development, visible flower buds (osteospermum) or beginning of flowering (impatiens) and at flowering. All plants produced with a moderate water deficit (irrigation at -3 and -10 kPa) were more compact than plants irrigated at -0,5 kPa but their flowering were not affected. Strong decrease in pIant growth and flowering was observed when plants were irrigated at the lowest water potential (-20 kPa). However, for impatiens the highest irrigation frequency was also not favorable. As a result of water stress the decrease in stomatal conductance (g~) in both plants was observed. Osteospermum was more resistant to water stress than impatiens.
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Bayer, Amanda. "Effect of Reduced Irrigation on Growth and Flowering of Coneflower and Sneezeweed." HortTechnology 30, no. 3 (2020): 315–21. http://dx.doi.org/10.21273/horttech04510-19.
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Reduced irrigation (RI) can be used to reduce irrigation volume as well as to control plant growth. The timing and duration of RI applications can affect overall plant growth and flowering. Knowledge of plant response to RI can allow growers to control growth and plant form. The objective of this study was to quantify flower and overall plant growth of ‘PAS702917’coneflower (Echinacea purpurea) and ‘Helbro’ sneezeweed (Helenium hybrida) in response to RI. A soil-moisture sensor automated irrigation system was used to apply four irrigation treatments: RI and well-watered (WW) controls (25% or 38%) and two alternating treatments to apply RI for either the first 2 weeks (25% followed by 38%, RIWW treatment) or final 4 weeks (38% followed by 25%, WWRI treatment) of the 6-week study. For the sneezeweed experiment, RI was reduced to 20%. For coneflower, peduncle length was greater for the WW (36.8 cm) and RIWW treatments (35.7 cm) than the RI (27.0 cm) and WWRI treatments (26.6 cm). Shoot dry weight, compactness, leaf area, and flower number were not significant. For sneezeweed, WW plants were taller (57.2 cm) and had greater shoot dry weight (49.8 g) than plants in other treatments. WW plants also had more flowers (99) than WWRI (63) and RI (67) plants, which were more compact. Total leaf area did not differ between treatments for either species. Total irrigation volume was greatest for WW plants (5.2 and 15.1 L/plant for coneflower and sneezeweed, respectively), with RI at any point during the experiment resulting in water savings.
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Bardsley, Alison. "Transanal irrigation systems for managing bowel dysfunction: a review." Gastrointestinal Nursing 18, no. 5 (2020): 18–28. http://dx.doi.org/10.12968/gasn.2020.18.5.18.
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Transanal irrigation (TAI) is used to treat bowel dysfunction, including faecal incontinence and constipation, where physical exercises, dietary changes and/or medication alone are insufficient. During TAI, water is instilled via the anal canal into the distal colon, and the water expels the faecal contents via wash out and/or stimulating colonic peristalsis. This can reduce the severity and frequency of bowel dysfunction, hospitalisation rate, management time and treatment costs and promotes dignity, independence and quality of life. Different TAI systems are available that instil a low or high volume of water, through a balloon catheter or a cone, using a manual or electric pump or a gravity feed. Balloon catheters are secure, convenient and comfortable, while cone systems may be considered less invasive but require patient or carer dexterity to be held in place. Low-volume systems are compact and convenient, but high-volume systems achieve better results for some conditions. Gravity-fed systems need to be suspended above the user, while electric pumps may be cumbersome. Bed systems are designed for patients who are bedbound or require hoisting. The optimal system should be selected based on assessment, informed by clinical need and patient preference. Users must be assessed by a specialist clinician for contraindications, comorbidities and capacity to consent. The clinician should then provide selected patients with ongoing structured training and support to ensure safe and effective use.
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Pouet, M. F., F. Persin, and M. Rumeau. "Intensive Treatment by Electrocoagulation - Flotation - Tangential Flow Microfiltration in Areas of High Seasonal Population." Water Science and Technology 25, no. 12 (1992): 247–53. http://dx.doi.org/10.2166/wst.1992.0356.
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In this paper, the authors present an electrochemical treatment associated to flotation. They want to show that microfiltration can be used in waste water treatment. For this, they have studied the coupling electrocoagulation - flotation, and they have studied the influence of this association on the flux of permeate in microfiltration. The conclusion of this work is that the combination of the three processes is a possible alternative to an extensive treatment in coastal areas. Moreover it is a compact process with which they have obtained a water of a quality suitable for irrigation.
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Dhaliwal, J., M. S. Kahlon, and S. S. Kukal. "Deep tillage and irrigation impacts on soil water balance and water productivity of direct-seeded rice–wheat cropping system in north-west India." Soil Research 58, no. 5 (2020): 498. http://dx.doi.org/10.1071/sr20018.
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Direct-seeded rice (DSR) is a potent option for north-west India considering the current shortages of labour and water. The formation of a subsurface compact layer in medium to coarse textured soils due to continuous puddling used for commonly grown puddled, transplanted rice hampers the root growth of DSR and wheat crops. It is thus imperative to study the deep tillage effects on water balance and water productivity of the DSR–wheat cropping system. A two-year field experiment was conducted during 2016–17 and 2017–18 in a sandy loam soil to study the soil water dynamics in relation to tillage and irrigation regimes in a DSR–wheat cropping system. There were two irrigation regimes both in DSR (irrigation at 4-day and 8-day intervals) and wheat (based on irrigation water to pan evaporation ratio of 1.0 (I1.0) and 0.5 (I0.5)) in main plots; with three tillage treatments in subplots: (1) conventional tillage for both DSR and wheat (DSRCT-WCT), (2) deep tillage before sowing of DSR during the first season + conventional tillage in wheat (DSRDT1-WCT) and (3) deep tillage before sowing of DSR during both seasons + conventional tillage in wheat (DSRDT2-WCT). The irrigation water input was lower by 325 mm under 8-day, I0.5 compared with 4-day, I1.0 irrigation regimes during both years. The evapotranspiration (ET) was significantly higher in plots with the 4-day compared to 8-day irrigation regime by 22.8% and 17.2% during 2016 and 2017 respectively. In wheat, ET was significantly higher in plots with I1.0 than I0.5 by 42.7% and 34.8% during 2016–17 and 2017–18 respectively. The ET was significantly higher in DSRDT2-WCT and DSRDT1-WCT than DSRCT-WCT in DSR. The water productivity was higher in less frequently (8-day and I0.5) than in frequently irrigated (4-day and I1.0) plots. Deep tillage during both seasons (DSRDT2-WCT) had no significant influence on the soil water balance components and water productivity in comparison to deep tillage only once in two years (DSRDT1-WCT). However, the ET and water productivity were significantly higher in plots with deep tillage compared to conventional tillage.
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Tassoula, Lamprini, Maria Papafotiou, Georgios Liakopoulos, and Georgios Kargas. "Growth of the Native Xerophyte Convolvulus cneorum L. on an Extensive Mediterranean Green Roof under Different Substrate Types and Irrigation Regimens." HortScience 50, no. 7 (2015): 1118–24. http://dx.doi.org/10.21273/hortsci.50.7.1118.
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The possibility of using Convolvulus cneorum L., a native Mediterranean xerophyte, with compact dome-like canopy and extended blooming period, on extensive green roofs in areas with semiarid Mediterranean climate was investigated in a 27-month experimental period, which included three summers (the dry season of the year). The aim was to preserve the local character and biodiversity, as well as to reduce water consumption and construction weight. Convolvulus cneorum rooted cuttings were planted in the beginning of July 2011 in experimental modules on a fully exposed flat roof at the Agricultural University of Athens, with a green roof infrastructure (substrate moisture retention and protection of the insulation, drainage element, and filter sheet). Two types of substrate with 10 cm depth were used, one with soil, i.e., grape marc compost:perlite:soil:pumice (3:3:2:2, v/v) and a lighter one without soil, i.e., grape marc compost:perlite:pumice (3:3:4, v/v). Two irrigation frequencies were applied during the dry periods, i.e., every 5 days (normal) and 7 days (sparse) in 2011 and 2012 and every 4 days (normal) and 6 days (sparse) in 2013. The chemical properties of the two substrates were similar, while their physical properties differ slightly as the substrate that contained soil was holding more water at saturation and it had lower saturated hydraulic conductivity and higher easily available water (EAW). The substrate type affected growth since plant height and diameter, shoot number, and aboveground dry weight were promoted by the soil substrate. Irrigation frequency did not affect plant growth. However, plants cultivated on soil substrate and irrigated normally had the highest growth, particularly compared with plants in soilless substrate under sparse irrigation. Flowering was abundant in April (spring) and in the first year flower number was promoted by the soil substrate. During the dry periods, sparse irrigation resulted in increased stomatal resistance one day before irrigation, indicating that water availability was marginal for the plants, while normal transpiration rate was restored the day after irrigation. According to photosystem II photochemical parameters measured one day before and the morning after an irrigation event, no evidence of damage to the photosynthetic apparatus was recorded in any of the treatments. In general, after 27 months of culture, plant size and roof coverage was appearing more or less similar in all the experimental treatments, therefore the combination of the lighter soilless substrate with sparse irrigation is highly suggested for C. cneorum cultivation on Mediterranean green roofs.
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Silva, Dilma Daniela, Richard C. Beeson, and Michael E. Kane. "Development of Shoot Architecture of Japanese Privet in Response to Soil Moisture." Journal of the American Society for Horticultural Science 140, no. 1 (2015): 50–56. http://dx.doi.org/10.21273/jashs.140.1.50.
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Bud outgrowth dynamics and their implications for shoot architecture were examined in japanese privet (Ligustrum japonicum) plants under well-irrigated [short irrigation cycle (SC)] and water-limitation [long irrigation cycle (LC)] conditions. New buds had limited sensitivity to dormancy, whereas preformed buds required more than one growing season to outgrow naturally. The first spring flush of shoot growth was mostly the result of lateral bud outgrowth, whereas latter flushes had prominent contributions of new apex buds. First flush terminal stems had mainly determinate growth (episodic). First flush lateral stems had increased occurrence of indeterminate growth (continuous). Water limitation influenced shoot architecture by enhancing apical dominance. Lateral branching was diminished 51% in LC plants compared with SC plants. As plants adapted to the stress imposed, indeterminate growth was triggered more often in meristematic regions of terminal buds of LC plants. In shoot flushes that occurred later in the stress treatment, old buds burst more frequently than the newly formed apex lateral buds. Plants under SC were more compact and better formed as an inverse triangle, whereas plants under LC had considerably less new branches and instead had long branches that would require pruning to maintain aesthetically pleasing shapes.
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Monteiro-Silva, Jorge, and Martins. "Optical Sensing of Nitrogen, Phosphorus and Potassium: A Spectrophotometrical Approach Toward Smart Nutrient Deployment." Chemosensors 7, no. 4 (2019): 51. http://dx.doi.org/10.3390/chemosensors7040051.
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The feasibility of a compact, modular sensing system able to quantify the presence of nitrogen, phosphorus and potassium (NPK) in nutrient-containing fertilizer water was investigated. Direct UV-Vis spectroscopy combined with optical fibers were employed to design modular compact sensing systems able to record absorption spectra of nutrient solutions resulting from local producer samples. N, P, and K spectral interference was studied by mixtures of commercial fertilizer solutions to simulate real conditions in hydroponic productions. This study demonstrates that the use of bands for the quantification of nitrogen with linear or logarithmic regression models does not produce analytical grade calibrations. Furthermore, multivariate regression models, i.e., Partial Least Squares (PLS), which consider specimens interference, perform poorly for low absorbance nutrients. The high interference present in the spectra has proven to be solved by an innovative self-learning artificial intelligence algorithm that is able to find interference modes among a spectral database to produce consistent predictions. By correctly modeling the existing interferences, analytical grade quantification of N, P, and K has proven feasible. The results of this work open the possibility of real-time NPK monitoring in Micro-Irrigation Systems.
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Jacobson, Alison Bingham, Terri W. Starman, and Leonardo Lombardini. "Substrate Moisture Content Effects on Growth and Shelf Life of Angelonia angustifolia." HortScience 50, no. 2 (2015): 272–78. http://dx.doi.org/10.21273/hortsci.50.2.272.
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Wilting during shelf life is a major cause of postharvest shrink for bedding plants shipped long distances from production greenhouses to retail outlets. The objective of this research was to determine if irrigation at lower, constant substrate moisture content (SMC) during greenhouse production would be a feasible way to acclimate plants for reduced shrinkage during shelf life while potentially conserving irrigation water. In two separate experiments conducted in the fall and spring seasons, rooted plugs of Angelonia angustifolia ‘Angelface Blue’ (angelonia) were grown in greenhouse production until a marketable stage in substrates irrigated at SMC levels of 10%, 20%, 30%, and 40% using a controlled irrigation system. At the end of the greenhouse production stage, plants were irrigated to container capacity and subjected to a simulated shipping environment in shipping boxes in the dark for 2 days. After shipping, plants were placed back in the greenhouse and watered minimally to simulate a retail environment. Data were taken at the end of each stage, i.e., greenhouse production, simulated shipping, and simulated retail. Results indicated that as SMC decreased from 40% to 10%, plants were shorter in height but had proportional and more compact flowering sections. The volume of water received by the 40% SMC plants was three times greater (fall) and 12 times greater (spring) than the 20% SMC plants during greenhouse production and two times greater (fall) and nine time greater (spring) during simulated retail. During production, midday water potentials decreased as the SMC levels decreased, but at the end of the simulated retail, the midday water potentials were the same, suggesting that plants that were drought-stressed during production were acclimated to lower water levels experienced in retail settings. Overall, the 20% SMC treatment produced the best postharvest quality plant resulting from reduced plant height without detrimental effects on flowering. The results demonstrate that while conserving water, controlled irrigation at a lower SMC can produce high-quality plants that have equal shelf life to those that are irrigated at high levels.
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Copes, Warren E., and H. Scherm. "Plant Spacing Effects on Microclimate and Rhizoctonia Web Blight Development in Container-grown Azalea." HortScience 40, no. 5 (2005): 1408–12. http://dx.doi.org/10.21273/hortsci.40.5.1408.
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Rhizoctonia web blight, caused by Rhizoctonia solani and binucleate Rhizoctonia spp., is an annual problem in compact cultivars of container-grown azalea (Rhododendron spp.) in the Gulf Coast states. Increasing the space between plants is commonly recommended for suppression of the disease, but experimental evidence for the effectiveness of this cultural practice in container-grown azalea is lacking. During the summers of 2002 and 2003, disease severity was measured weekly in the inoculated center plant of plots consisting of 49 potted `Gumpo White' azalea plants growing in 3.8-L containers and having a canopy diameter of about 30 cm. Plant spacing within plots was 0, 6, 12, 18, or 24 cm, and plots were arranged in three randomized complete blocks. Evaporation, leaf wetness (LW), relative humidity (RH), and temperature were monitored in each plot. Disease severity increased steadily from mid-July to late August or early September, after which it leveled off or declined. Evaporation increased and the number of hours within the temperature range favorable for disease development (25 to 30 °C) decreased significantly with plant spacing (P < 0.05), but LW and RH were not significantly different among treatments. Plant spacing also had no significant effect on disease severity. Daily overhead irrigation and compact plant form likely contributed to the lack of effect of spacing on disease development.
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Acosta-Motos, José Ramón, María Fernanda Ortuño, Sara Álvarez, José Antonio Hernández, and María Jesús Sánchez-Blanco. "The use of reclaimed water is a viable and safe strategy for the irrigation of myrtle plants in a scenario of climate change." Water Supply 19, no. 6 (2019): 1741–47. http://dx.doi.org/10.2166/ws.2019.048.
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Abstract In this work, we irrigated myrtle plants with reclaimed waters (RWs) for 90 days with drainage. The treatments consisted of a control (0.8 dS m−1) and two RWs: RW1 (2.0 dS m−1) and RW2 (5.0 dS m−1). In general, nutrients were accumulated in a greater proportion in shoots than in roots and increased in the RW treatments, with the exception of potassium and phosphorus. This behaviour produced a progressive decrease in the root water potential, which hindered the mobility of water to the leaves. This in turn caused a drop in leaf water potential and gas exchange parameters, especially in the RW2 treatment. The intrinsic water-use efficiency (WUEi, Pn/gs) did not show differences in any treatment. The RW2 treatment provoked a loss of biomass in the leaves but not in the stems and roots, resulting in more compact plants. Considering these results together, it is feasible to use RWs for plant irrigation, despite their high electrical conductivity. RWs are thus a viable alternative to scarce conventional water resources in a future scenario of climate change.
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Silva, Dilma Daniela, and Richard C. Beeson. "A Large-volume Rhizotron for Evaluating Root Growth Under Natural-like Soil Moisture Conditions." HortScience 46, no. 12 (2011): 1677–82. http://dx.doi.org/10.21273/hortsci.46.12.1677.
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An experimental system that allows imposition of precise irrigation treatments with easy and quick observations of unrestricted root growth of woody plants was developed. The system mimics natural deep soil percolation and facilitates rapid assessment of large root populations. It was designed to be relatively inexpensive to build so that treatments could be efficiently replicated. Designs for this star-shaped rhizotron were developed and evaluated with the goals of: 1) optimizing volume and shape for minimal physical restriction and use with mature woody plants; 2) developing a drainage system comparable to natural deep soils; and 3) facilitating ease, accuracy, and duration of data acquisition. The final design allows efficient root observation, uses a wick-type drainage system to provide a near-uniform profile of soil moisture, and is easily manageable for precise long-term data acquisition. This rhizotron has eight independent viewing/sampling windows and holds 0.16 m3 of soil. An associated lightweight and compact camera positioning frame was developed that facilitates acquisition of digital photographs of soil profiles for time-series assessment of morphological and architectural parameters.
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Shang, Haixin, Song Xu, Kuandi Zhang, and Luyou Zhao. "Explicit Solution for Critical Depth in Closed Conduits Flowing Partly Full." Water 11, no. 10 (2019): 2124. http://dx.doi.org/10.3390/w11102124.
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Critical depth is an essential parameter for the design, operation, and maintenance of conduits. Circular, arched, and egg-shaped sections are often used in non-pressure conduits in hydraulic engineering, irrigation, and sewerage works. However, equations governing the critical depth in various sections are complicated implicit transcendental equations. The function model is established for the geometric features of multiple sections using the mathematical transform method and while considering non-dimensional parameters. Then, revised PSO algorithms are implemented in MATLAB, and the right solution’s formula for the critical depths in various non-pressure conduit sections is established through optimization. The error analysis results show that the established formula has broad applicability. The maximum relative errors of the formula for critical depths are less than 0.182%, 0.0629%, and 0.170% in circular, arched, and egg-shaped sections, respectively, which are more accurate than those of existing formulas; the form of the formula proposed in this work is also more compact than that of the existing formulas. The results of this research may be useful in design, operation, and maintenance in conduit engineering.
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Strzelczyk, Maria, and Aleksandra Steinhoff-Wrześniewska. "Effectiveness of domestic rural wastewater treatment in soil-plant system." Geology, Geophysics and Environment 45, no. 4 (2020): 247. http://dx.doi.org/10.7494/geol.2019.45.4.247.
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The characteristics of Polish rural agglomerations indicate that only 32% of these areas are villages typified by compact buildings where the use of a collective sewage system is economically justified. In other areas, it is necessary to apply solutions that allow for the sewage utilization in place of their creation and safe discharge into the environment, e.g. in the form of home systems based on biological processes, e.g. in soil-plant systems. The purpose of the work was to determine the soil-plant efficiency of wastewater treatment with the use of so-called energy plants. The experiment was conducted in 2012–2014 in lysimeters at a depth of 130 cm and 100 cm in diameter. These were submerged in the ground, filled with sand clay and equipped with installations enabling the drain-age of gravity water in the form of lysimeter effluents. Two species of plants were used: Miscanthu giganteus and Sida hermaphrodita (L.) Rusby. They were irrigated with pre-treated domestic sewage (variant I – 1200 mm · year−1 and variant II – 1600 mm · year−1). For irrigation, sewage from a group of buildings inhabited by six families was used. Raw domestic sewage was discharged into the tank, consisting of four chambers, which constituted a relatively good level of pre-cleaning. For the irrigation of plants in the experiment, pre-treated sewage was used. In order to determine the effectiveness of wastewater treatment in the soil-plant environment, the concentrations of the following components were determined in the effluents: TSS, BOD5, COD, Ntot. The quantities of pollutants contained in the sewage were characterized by considerable variability, especially in relation to COD (390.6–1583.0 mg O2· dm−3) and Ntot (47.0–250.2 mg N · dm−3).
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Guo, Yanjun, Terri Starman, and Charles Hall. "Growth, Quality, and Economic Value Responses of Bedding Plants to Reduced Water Usage." HortScience 54, no. 5 (2019): 856–64. http://dx.doi.org/10.21273/hortsci13793-18.
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This study analyzed the effects of two ranges of drying down of substrate moisture content (SMC) before re-watering on plant growth and development, postproduction quality, and economic value of bedding plants grown in 1.67-L containers during greenhouse production. The two SMC treatments were wide-range (WR) SMC (WR-SMC) for dry-down from container capacity (CC) of 54% SMC dried down to 20% SMC or narrow-range (NR) SMC (NR-SMC) for dry-down from CC of 54% SMC dried down to 40% SMC. Six bedding plant cultivars were used [Solenostemon scutellarioides ‘French Quarter’ (coleus); Petunia ×hybrida ‘Colorworks Pink Radiance’ (petunia); Lantana camara ‘Lucky Flame’ (lantana); Impatiens ×hybrida ‘Sunpatiens Compact Hot Coral’ (SCC); ‘Sunpatiens Spreading Lavender’ (SSL) (impatiens); and Salvia splendens ‘Red Hot Sally II’ (salvia)]. Shoot dry weight was reduced with WR-SMC on petunia, lantana, impatiens SCC, and salvia at the end of production. With WR-SMC, the petunia and impatiens SCC root ball coverage percentages were greater on the bottom of the container, whereas those of impatiens SSL and salvia were reduced. The WR-SMC increased petunia postproduction quality by increasing the flower number. Lantana and impatiens SCC inflorescence/flower and/or bud number were reduced with WR-SMC. The impatiens SSL flower number was unaffected by SMC treatment. Salvia grown with WR-SMC had increased postproduction quality. WR-SMC reduced postproduction water potential in petunia, lantana, and coleus, suggesting that plants with WR-SMC during production were acclimated to reduced irrigation administered during postproduction. WR-SMC saved labor due to less frequent watering and overhead-associated costs due to reduced bench space, with the exception of coleus and impatiens SSL, which used the same bench space as NR-SMC. Considering production and/or postproduction quality, using WR-SMC during greenhouse production is beneficial as an irrigation method for coleus, petunia, impatiens SSL, and salvia, but not for impatiens SCC or lantana grown in 1.67-L containers.
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Galappaththi, Himan K. A., and Inoka Suraweera. "Risk of Mercury exposure during childhood: a review of Sri Lankan situation." Reviews on Environmental Health 35, no. 3 (2020): 229–32. http://dx.doi.org/10.1515/reveh-2020-0024.
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AbstractSri Lanka had ratified the Minamata convention in the year 2017 and is planning to phase out Mercury by 2020. Mercury thermometers and compact fluorescent light bulbs are abundant at hospitals, households and schools. Limitations in safe disposal and containment mechanisms have enhanced the unregulated e-waste collection and extraction. Sri Lanka has plentiful lagoons, fishing bays, and inland irrigation systems. Fish consumption is high, especially around the coastal belt. Mercury can bioaccumulate in humans by the consumption of fish from contaminated sources. Children are at risk of exposure in their living environments and via food. A multicountry study done across three oceans on Mercury threat to women & children revealed, lagoon pollution from industrial Mercury emissions in Sri Lanka, possessing high Mercury among local females who consume fish from that lagoon. The mean hair Mercury level in coastal areas with high fish consumption exceeded the reference dose even among children. Aquatic life and crop studies revealed a mixed picture of Mercury levels which some are lower and some are higher than the permissible levels. Studies on environmental Mercury levels and correlations with health effects among children will help to fill the data gap. Public awareness of the health effects of Mercury and mechanisms of Mercury disposal should be established.
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Cucci, Giovanna, Giovanni Lacolla, Marcello Pagliai, and Nadia Vignozzi. "Effect of reclamation on the structure of silty-clay soils irrigated with saline-sodic waters." International Agrophysics 29, no. 1 (2015): 23–30. http://dx.doi.org/10.1515/intag-2015-0005.
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Abstract The objective of the work was to evaluate, by using the micromorphometric method, the effects of reclamation on porosity of two different clay loam soils irrigated with saline-sodic waters. Soil samples of the Ap horizon were put in cylindrical containers and irrigated with 9 types of saline-sodic waters (3 levels of salinity combined with 3 levels of sodicity). After a 4-year period, correction treatments were initiated by addition of calcium sulphate and leaching until electrical conductivity and sodium absorption ratio values of the drainage water matched 3 dS m-1 and 9, respectively. After 2 years of correction treatments, undisturbed soil samples were taken from the surface layer and soil thin sections for porosity measurements. Both soils did not show critical macroporosity values (> 10%, below this threshold a soil is classified as compact). Nevertheless, the soils exhibited a different behaviour: total porosity of the Pachic Haploxeroll soil was not affected by difference in water salinity and alkalinity; on the contrary, the Udertic Ustochrept soil showed a lower porosity associated with higher salt concentration in the irrigation waters. This may be due to the different iron and aluminium sesquioxides content and, as a consequence, a different effect on soil aggregate stability.
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Al-Mossawi, Muhsin A. J. "Biological Approach for Recycling Waste Water in Iraq." Air, Soil and Water Research 7 (January 2014): ASWR.S17611. http://dx.doi.org/10.4137/aswr.s17611.
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The middle and southern parts of Iraq are exposed to a series of serious drought-related problems. This is mainly linked to the absence of applied international law for water distribution in the Euphrates and Tigris rivers between Turkey, Syria, and Iraq, in addition to climate change and unawareness of the water resource problems for more than three decades. The Inter-Agency Information and Analysis Unit of the United Nations reported that water in the Tigris and Euphrates will decrease by up to 80% and 50%, respectively, by 2025. Therefore, water recycling would be an essential and inevitable sustainable approach under these circumstances. The biological treatment of sewage, industrial waste water, scientific laboratories effluent, and irrigation waters using compact units is described here to be involved in solving the water shortage in Iraq. The main indicators used to assess the efficiency of these units are chemical oxygen demand (COD), biological oxygen demand (BOD), total solved salts (TSS), and total fecal coliforms (TFC). These units have been approved to treat contaminated waters with 10-fold pollutants in a fifth of the time required as compared to other classical procedures. In conclusion, using these treatment units will be useful in tackling the problem of water shortage in Iraq and could potentially be the best control method to stop the spread of infectious diseases obtained from contaminated waters.
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Marek, Gary W., Paul D. Colaizzi, Steven R. Evett, Jerry E. Moorhead, David K. Brauer, and Brice B. Ruthardt. "Design, Fabrication, and Operation of an In-Situ Microlysimeter for Estimating Soil Water Evaporation." Applied Engineering in Agriculture 35, no. 3 (2019): 301–9. http://dx.doi.org/10.13031/aea.13140.
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Abstract. Evapotranspiration (ET) or crop water use is the major consumptive use of irrigation and precipitation, commonly accounting for the largest component of the water balance. As water resources become scarce, agricultural research aims to increase water use efficiency by maintaining profitable crop yields while reducing ET. Advanced understanding of ET in the soil-plant-atmosphere continuum requires quantification of evaporation (E) and transpiration (T) components. However, the partitioning of E and T can be challenging even when using high quality ET data. Microlysimeters can be used to measure E from the soil surface and estimate T by subtraction using quality ET data. However, an understanding of the limitations of small, hydraulically isolated microlysimeters is required for meaningful interpretation of results. Proper design, fabrication, and operation of microlysimeters can yield reliable estimates of E from bare soil. Multiple microlysimeters and strategic placement may be required for accurate estimates of E in row crops, particularly during incomplete plant canopy conditions. Periodic weighing of lysimeter cores allows for time-averaged measurements of E but precludes E rate data at finer time scales. Design and testing of continuous weighing platforms to improve temporal density of microlysimeter measurements is needed. We present design and fabrication details of a compact, inexpensive, microlysimeter for field estimates of E in agricultural soils. Installation and operation techniques are also provided with discussion of example field data. Keywords: Evapotranspiration, Lysimetry, Microlysimeter, Soil evaporation.
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Nichols, S. N., R. W. Hofmann, and W. M. Williams. "Drought resistance of Trifolium repens×Trifolium uniflorum interspecific hybrids." Crop and Pasture Science 65, no. 9 (2014): 911. http://dx.doi.org/10.1071/cp14067.
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White clover (Trifolium repens L.) is a widely used and highly valued temperate legume; however, its productivity and survival are restricted under dryland and drought conditions. This study investigated whether drought resistance of white clover could be improved by interspecific hybridisation with Trifolium uniflorum L. After almost 4 months without irrigation in a rain-shelter facility, shoot dry weight (DW) decreased significantly less in first-generation backcross (BC1) hybrids (–47%) than second-generation backcross (BC2) hybrids (–68%) and white clover (–69%). Stolon morphological parameters such as internode length and leaf lamina area also decreased less under water stress in the BC1 hybrids than in BC2 and white clover. There was also lower senescence in BC1 under water stress than in the other clover types. Genotypes with smaller changes in leaf lamina area, internode length, senescence and lateral spread had smaller changes in shoot DW, and there were significant correlations between constitutive levels of some characteristics and the effect of water stress on shoot DW. Under water stress, the growth form of the BC1 hybrids was compact, dense and prostrate, whereas white clover was more spreading and open. Increased allocation of dry matter to roots under drought, and greater root diameter, may also have influenced the ability of BC1 hybrids to maintain water uptake and key physiological processes. Overall, the data confirm that the drought resistance of white clover can be improved through hybridisation with T. uniflorum.
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Kirschner, Gwendolyn K., Ting Ting Xiao, and Ikram Blilou. "Rooting in the Desert: A Developmental Overview on Desert Plants." Genes 12, no. 5 (2021): 709. http://dx.doi.org/10.3390/genes12050709.
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Plants, as sessile organisms, have evolved a remarkable developmental plasticity to cope with their changing environment. When growing in hostile desert conditions, plants have to grow and thrive in heat and drought. This review discusses how desert plants have adapted their root system architecture (RSA) to cope with scarce water availability and poor nutrient availability in the desert soil. First, we describe how some species can survive by developing deep tap roots to access the groundwater while others produce shallow roots to exploit the short rain seasons and unpredictable rainfalls. Then, we discuss how desert plants have evolved unique developmental programs like having determinate meristems in the case of cacti while forming a branched and compact root system that allows efficient water uptake during wet periods. The remote germination mechanism in date palms is another example of developmental adaptation to survive in the dry and hot desert surface. Date palms have also designed non-gravitropic secondary roots, termed pneumatophores, to maximize water and nutrient uptake. Next, we highlight the distinct anatomical features developed by desert species in response to drought like narrow vessels, high tissue suberization, and air spaces within the root cortex tissue. Finally, we discuss the beneficial impact of the microbiome in promoting root growth in desert conditions and how these characteristics can be exploited to engineer resilient crops with a greater ability to deal with salinity induced by irrigation and with the increasing drought caused by global warming.
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Andales, Allan A., Dale Straw, Thomas H. Marek, Lane H. Simmons, Michael E. Bartolo, and Thomas W. Ley. "Design and Construction of a Precision Weighing Lysimeter in Southeast Colorado." Transactions of the ASABE 61, no. 2 (2018): 509–21. http://dx.doi.org/10.13031/trans.12282.
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Abstract. Accurate estimates of crop evapotranspiration (ET) are needed to effectively manage irrigation resources in the Arkansas River basin in Colorado and to maintain compliance with the Arkansas River compact with Kansas. This was a major impetus for the construction of a precision weighing lysimeter in the Arkansas River basin at the Colorado State University (CSU) Arkansas Valley Research Center (AVRC) near Rocky Ford, Colorado. The objective of this article is to describe the design and construction of the weighing lysimeter and characterize its performance and unique features. The main components of the lysimeter facility are the foundation, the scale system, the soil monolith tank, and the outer tank that houses the aforementioned components. The foundation, which was 4.12 m below the ground surface, consisted of a reinforced concrete slab 2.00 m wide by 6.31 m long and 0.20 m thick that was anchored to six square shaft helical anchors. The outer tank was secured onto the foundation and had a rectangular floor area of 6.10 m × 1.79 m (10.92 m2), an interior vertical clearance of 2.15 m, and walls made of reinforced 8 mm thick steel plates. The floor scale system (mechanical levers and load cell) was installed inside the outer tank and had a gross capacity of 17 Mg. The monolith tank (1.50 m × 1.50 m area, 2.44 m depth, 10 mm steel walls) containing an undisturbed soil profile was set on the scale system. The lysimeter facility was installed in the middle of a 3.5 ha field. Calibration of the scale system resulted in a linear response (R2 = 1.000), with an equivalent conversion coefficient (slope) of 151.09 mm H2O (mV V-1)-1. The sensitivity of the scale system was 0.023 mm of water, which is sufficient for measuring diurnal (15 min to hourly) changes in ET and soil water. Load cell readings taken at a frequency of 0.5 Hz were averaged in 15 min intervals (450 readings per 15 min) to filter out the measurement noise that was attributed to wind. The lysimeter was found to adequately detect ET, irrigation, and precipitation perturbations with an actively growing alfalfa hay crop ( L.) in 2011. The lysimeter facility is a state-of-the-art tool for quantifying ET of irrigated crops in the lower Arkansas basin in southeast Colorado. Keywords: Calibration, Evapotranspiration, Load cell, Weighing lysimeter.
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Pitchay, Dharmalingam S., and Paul V. Nelson. "130 Impact of Fertilizer N Forms on Bedding Plant Development." HortScience 34, no. 3 (1999): 464A—464. http://dx.doi.org/10.21273/hortsci.34.3.464a.
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It is a common practice in greenhouses to apply fertilizers with a high proportion of N in the NO3 form to achieve short, compact shoots and a moderate (25% or greater) proportion of NH4 or urea for large shoots. However, this practice is not substantiated in the scientific literature. Two experiments were conducted in a greenhouse to assess effects of N form on development. In the first, Petunia hybrida `Mid-night Dreams' was treated with five ratios of NH4:NO3 or urea:NO3 in a factorial arrangement with three concentrations of N (50-low, 100-adequate, and 200-high mg/L at each irrigation). In the second experiment six species of bedding plants were treated in a factorial arrangement of five ratios of NH4:NO3 and two pH levels (acceptably low, 5.4-5.8, and unacceptably low, 4.6-5.2). In all comparisons, height and dry weight of shoots grown with 100% NO3 were equal or larger than the plants grown with combinations of N. There was a general trend for plants to be shorter and lighter at higher NH4 or urea proportions. These results refute the hypothesis that shoot size is under the control of N form. Depth of green foliar color correlated positively with proportion of NH4 or urea. Reputed NH4 toxicity symptoms of chlorosis, necrosis, and curling of older leaves occurred only at adversely low pH levels below 5.2 in experiment 2. Resistance of plants to this disorder under conditions of pH levels in the range of 5.4 to 5.8, high N application rates, and applications of 100% NH4 indicates that bedding plants during commercial production are fairly resistant to this disorder.
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Korotenko, Tatyana, Semen Yurchenko, and Lyubov Esaulova. "Plant productivity parameters in rice varieties with different type of panicles and their variability." E3S Web of Conferences 285 (2021): 02031. http://dx.doi.org/10.1051/e3sconf/202128502031.
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To increase rice yield, scientists are considering the possibility of changing the morphological parameters of plants. At the same time, there are not enough attempts in Russia to analyze the yield potential of varieties with different panicle architectonics. The purpose of our research was a comparative analysis of rice varieties differing in panicle morphotype, by the formation of productivity elements. In the ecological conditions of the south of Russia, in 2019-2020, a series of field experiments were carried out with 24 Oryza sativa L. varieties under conditions of artificial irrigation. The results of assessing the elements of plant productivity and biological productivity of varieties differentiated into 6 groups according to the panicle type and grown on plots 1x12 m are presented. The present study showed that in the rice-growing zone of Krasnodar region, varieties with a compact inclined and slightly spreading panicle had an advantage in achieving high productivity. However, the stability of quantitative traits was exhibited by varieties with spreading panicles of the drooping type. Correlation analysis confirmed: the longer the panicle, the more spreading it is and the less sterile spikelets are formed on it. Along with other researchers, we revealed significant differences in yield between japonica and Indica varieties. Due to the cultivation of varieties under equal conditions, the variation in biological yield from 778 to 1203 g / m2 can be explained by their genotypic characteristics. For the sustainable development of rice growing in the region, our studies emphasize the importance of the diversity of varieties of various morphotypes with high potential and stability of productivity elements and provide useful information for breeding.
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Abedi, T., and Moghaddami Sh. "Phytoremediation concept: biomass production and growth of Populus deltoides under compost leachate irrigation." Journal of Forest Science 61, No. 6 (2016): 250–54. http://dx.doi.org/10.17221/121/2014-jfs.
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Cochran, Diana R., Amy Fulcher, and Guihong Bi. "Efficacy of Dikegulac Sodium Applied to Pruned and Unpruned ‘Limelight’ Hydrangea Grown at Two Locations in the Southeastern United States." HortTechnology 23, no. 6 (2013): 836–42. http://dx.doi.org/10.21273/horttech.23.6.836.
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Pruning is commonly performed during production of nursery crops to produce symmetrical, compact plants that are pleasing to the consumer’s eye. To achieve the desired results, nursery growers hand prune or apply plant growth regulators (PGRs). However, hand pruning is expensive and is not always effective, and efficacy of PGRs can depend on cultural practices, environmental conditions, irrigation, cultivar, and rate. Therefore, the objective of these experiments was to evaluate the effect of dikegulac sodium applied to pruned or unpruned ‘Limelight’ hardy hydrangea (Hydrangea paniculata). Plants were grown at two locations, Tennessee (TN) and Mississippi (MS). The pruned treatment consisted of hand pruning, leaving three nodes followed by applications of dikegulac sodium (400, 800, or 1600 ppm). Applications of dikegulac sodium to pruned or unpruned plants were made the same day using a carbon dioxide backpack sprayer. There were two additional control treatments: hand-pruned untreated (hand-pruned) and unpruned untreated (untreated). Plants were grown outdoors under full sun in TN and under 40% shade in MS. Data were collected at the close of the experiment on the number of branches over 1 inch, final growth index (FGI), floral attributes, branch symmetry, and phytotoxicity. At both locations, pruned and unpruned plants treated with 800 or 1600 ppm dikegulac sodium had more branches than the hand-pruned and unpruned plants. Flower number and size tended to be greater for unpruned plants than pruned plants. Phytotoxicity was observed at 2 and 6 weeks after treatment (WAT). For plants grown in TN, symptoms were more pronounced on plants following treatment with 800 (pruned plants) and 1600 ppm (pruned and unpruned) dikegulac sodium compared with the untreated plants. There were no visible phytotoxicity symptoms at 6 WAT for plants grown in MS, regardless of treatment.
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Fare, Donna C., Charles H. Gilliam, Gary J. Keever, and John W. Olive. "Cyclic Irrigation Reduces Container Leachate Nitrate-nitrogen Concentration." HortScience 29, no. 12 (1994): 1514–17. http://dx.doi.org/10.21273/hortsci.29.12.1514.
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Two experiments were conducted to evaluate the effects of cyclic irrigation on leachate NO3-N concentration, container leachate volume, total effluent volume, and growth of Ilex crenata Thunb. `Compacta'. In Expt. 1, container leachate volume was reduced 34% when 13 mm of water was applied in three cycles compared to continuous irrigation of 13 mm per unit time. Forty-nine percent less container leachate volume was collected from a continuous application of 8 mm than from that of 13 mm water. In Expt. 2, container leachate volume was reduced 71% when 6 mm was applied in a single application over 30 minutes compared to 13 mm applied continuously for 1 hour. Total effluent was reduced by 14% and 10% in Expts. 1 and 2, respectively, when 13-mm irrigation was applied in three cycles compared to one continuous irrigation. Container leachate NO3-N concentrations from cyclic irrigation were generally less than leachate NO3-N concentrations from continuous irrigation treatments. The percentage of applied N leached as NO3-N ranged from 46% when 13-mm irrigation was applied in three cycles to 63% when 13-mm irrigation was applied in a single cycle. Leachate NO3-N concentration was reduced as irrigation volume was reduced from 13 to 6 mm in Expt. 2. Percentage of applied N leached as NO3-N was 63%, 56%, and 47% when 13-mm irrigation was applied in one, two, and three cycles, respectively, compared to 19%, 16%, and 15% when 6-mm irrigation was applied in one, two, and three cycles, respectively. `Compacta' holly shoot and root growth were minimally affected by cyclic irrigation or irrigation volume.
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Eakes, D. J., C. H. Gilliam, H. G. Ponder, C. E. Evans, and M. E. Marini. "Effect of Trickle Irrigation, Nitrogen Rate, and Method of Application on Field-grown ‘Compacta’ Japanese Holly." Journal of Environmental Horticulture 8, no. 2 (1990): 68–70. http://dx.doi.org/10.24266/0738-2898-8.2.68.
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Abstract Three methods of N application and 4 N rates of 34, 67, 134, and 268 kg/ha (30,60 120, and 240 lbs/A) were evaluated on field-grown ‘Compacta’ Japanese holly (Ilex crenata Thunb. ‘Compacta’). Fertilizer application methods consisted of NH4NO3 broadcast over trickle irrigated and non-irrigated plants, and injection of NH4NO3 through the trickle irrigation system. Irrigation regardless of whether N was surface applied or injected through the system, increased root and shoot dry weights, plant size, visual ratings, and percent survival. Irrigated plants had a more fibrous root system. N rate had no affect on root or shoot dry weights, root distribution, visual ratings, or percent survival.
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Eastwood, Kyle W., Vivek P. Bodani, Faizal A. Haji, Thomas Looi, Hani E. Naguib, and James M. Drake. "Development of synthetic simulators for endoscope-assisted repair of metopic and sagittal craniosynostosis." Journal of Neurosurgery: Pediatrics 22, no. 2 (2018): 128–36. http://dx.doi.org/10.3171/2018.2.peds18121.
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OBJECTIVEEndoscope-assisted repair of craniosynostosis is a safe and efficacious alternative to open techniques. However, this procedure is challenging to learn, and there is significant variation in both its execution and outcomes. Surgical simulators may allow trainees to learn and practice this procedure prior to operating on an actual patient. The purpose of this study was to develop a realistic, relatively inexpensive simulator for endoscope-assisted repair of metopic and sagittal craniosynostosis and to evaluate the models’ fidelity and teaching content.METHODSTwo separate, 3D-printed, plastic powder–based replica skulls exhibiting metopic (age 1 month) and sagittal (age 2 months) craniosynostosis were developed. These models were made into consumable skull “cartridges” that insert into a reusable base resembling an infant’s head. Each cartridge consists of a multilayer scalp (skin, subcutaneous fat, galea, and periosteum); cranial bones with accurate landmarks; and the dura mater. Data related to model construction, use, and cost were collected. Eleven novice surgeons (residents), 9 experienced surgeons (fellows), and 5 expert surgeons (attendings) performed a simulated metopic and sagittal craniosynostosis repair using a neuroendoscope, high-speed drill, rongeurs, lighted retractors, and suction/irrigation. All participants completed a 13-item questionnaire (using 5-point Likert scales) to rate the realism and utility of the models for teaching endoscope-assisted strip suturectomy.RESULTSThe simulators are compact, robust, and relatively inexpensive. They can be rapidly reset for repeated use and contain a minimal amount of consumable material while providing a realistic simulation experience. More than 80% of participants agreed or strongly agreed that the models’ anatomical features, including surface anatomy, subgaleal and subperiosteal tissue planes, anterior fontanelle, and epidural spaces, were realistic and contained appropriate detail. More than 90% of participants indicated that handling the endoscope and the instruments was realistic, and also that the steps required to perform the procedure were representative of the steps required in real life.CONCLUSIONSBoth the metopic and sagittal craniosynostosis simulators were developed using low-cost methods and were successfully designed to be reusable. The simulators were found to realistically represent the surgical procedure and can be used to develop the technical skills required for performing an endoscope-assisted craniosynostosis repair.
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Бабинцева, Нина Александровна, and Тарас Григориевич Фоменко. "The Crimean Spindle as a prospective crown shape for growing fruit trees in intensive gardens of Crimea." Magarach Vinogradstvo i Vinodelie, no. 1(115) (March 22, 2021): 32–36. http://dx.doi.org/10.35547/im.2021.93.18.005.
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В статье освещены результаты технологической оценки перспективной формы кроны - «крымское веретено» с сортами Бреберн, Джалита и Ренет Симиренко на подвое ЕМ-IХ в условиях Крыма. Целью исследований является изучение технологических характеристик формы кроны для создания высокоплотных садов. Работа проводится по методикам полевых исследований с плодовыми культурами. Установлено, что за счет использования технологически нетрудоемкой формы кроны обеспечивается урожайность в 29,5 т/га, на шестой год после посадки сада, с выходом товарной продукции до 99 %. Крона имеет компактные размеры: параметры горизонтальной проекции варьируют от 1,8 м (сорта Джалита, Бреберн) до 2,2 м (сорт Ренет Симиренко); объём - от 2,7 до 3,1 м. Затраты ручного труда находятся в прямой зависимости от биологических особенностей сорта. Трудоемкость обрезки 1 га сада с обозначенной формой кроны составляет от 84,4-86,7 (сорта Джалита, Ренет Симиренко) до 124,9 чел./ч (сорт Бреберн). При соблюдении всех технологических приемов формирования кроны, высокой агротехники и капельного орошения обеспечивается ежегодная урожайность и высокое качество продукции, при минимальных затратах труда. The article highlights the results of technological assessment of a promising crown shape - a Crimean Spindle with ‘Brebern’, ‘Dzhalita’ and ‘Renet Simirenko’ varieties on the ‘EM IX’ rootstock in the conditions of Crimea. The goal of the research is to study technological characteristics of the crown shape for creation of ultra-dense gardens. The work is carried out according to the methods of field study with fruit crops. It has been established that due to the use of a technologically labor saving crown shape, cropping capacity of 29.5 t/ha is provided on the sixth year after planting the garden, with a commercial yield of up to 99%. The crown has compact dimensions with the parameters of horizontal projection of the crown varying from 1.8 m (‘Dzhalita’, ‘Brebern’) - to 2.2 m (‘Renet Simirenko’), and volume - from 2.7 to 3.1 m. The cost of manual labor is in direct relationship to the biological characteristics of variety. Labor intensity of pruning 1 hectare of a garden with the above-mentioned crown shape ranges from 84.4 - 86.7 (‘Dzhalita’, ‘Renet Simirenko’) to 124.9 m/hrs. (‘Brebern’). If all technological methods of crown shaping, high agricultural technology and drip irrigation are obeyed, the annual cropping capacity and high quality products are ensured with minimal labor costs for cultivation.
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Guo, Yanjun, Terri Starman, and Charles Hall. "Reducing Substrate Moisture Content during Greenhouse Production of Poinsettia Improves Postproduction Quality and Economic Value." HortScience 53, no. 11 (2018): 1618–28. http://dx.doi.org/10.21273/hortsci13484-18.
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The objective was to determine the effect of substrate moisture content (SMC) during poinsettia (Euphorbia pulcherrima) greenhouse production on plant quality, postproduction longevity, and economic value. Two experiments were conducted, one in 2016 with ‘Freedom Red’ and the other in 2017 with ‘Christmas Eve Red’. Treatments included two SMC levels (20% or 40%) applied in four timing of application combinations. Total production (TP) time was 14 (2016) or 12 (2017) weeks in which vegetative production (VP) occurred from week 33 (2016) or 35 (2017) to week 39 and reproductive production (RP) continued from week 40 to 47. The four timing of application treatments were 40/40 = TP at 40% SMC; 20/40 = VP at 20% + RP at 40%; 40/20 = VP at 40% + RP at 20%; 20/20 = TP at 20% SMC. After simulated shipping in the dark, plants were evaluated in a simulated retail environment with two packaging treatments: no sleeve covering or plastic perforated plant sleeves covering container and plant. At the end of greenhouse production, plants grown in 20% SMC during RP (20/20 and 40/20) had shorter bract internode length, stem length, and smaller growth index (GI), decreased shoot and root dry weight (DW), and bract and leaf surface area compared with those in 40% SMC during RP (40/40 and 20/40). Photosynthetic rate was higher when plants were watered at 40% SMC regardless of production stage compared with those in 20% SMC. Leaf thickness, petiole thickness, total bract and leaf number were unaffected by SMC treatments. Plants in 20% SMC during RP (20/20 or 40/20) had earlier bract coloring despite days to anthesis being the same for all SMC treatments. Compared with 40/40, 40/20, and 20/20 could save 44.2% or 43.6%, respectively, irrigation and fertilizer usage, and 39.1% and 47.8%, respectively, labor time. During postharvest, ethylene concentration was unaffected by packaging method. Sleeved plants, regardless of SMC treatment, received lower light intensity in the middle of the plant canopy, causing plants to have lower total leaf number due to abscission and SPAD reading at the end of postproduction. The 40/40 treatment abscised more bracts during five weeks (in 2016) of postproduction and with no sleeve had higher number of bracts with bract edge burn (BEB). In summary, reducing SMC to 20% during TP or RP reduced water usage during production and produced more compact plants with increased postproduction quality.
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Sujana, I. Putu. "The application of biochar to screen printing liquid waste polluted land, its effect in soil, mustard greens to heavy metals (Fe, Cr)." Research Journal of Textile and Apparel 22, no. 3 (2018): 224–34. http://dx.doi.org/10.1108/rjta-02-2018-0006.
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Purpose The purpose of this paper is to analyse the screen printing liquid waste polluted soil physical, chemical and biological characteristics, with the unpolluted soil, and to analyse the application of some types of biochar towards the growth of mustard greens plants and the concentration of heavy metals Fe, Cr on the screen printing liquid waste polluted soil. Design/methodology/approach This research was conducted in a green house by using fully randomized design, split plot design pattern, with three replications. The main plot is the type of biochar, and the subplot is the dosage of biochar. The biochar consists of four types (B1 = chicken manure biochar, B2 = coconut shell biochar, B3 = rice hulls biochar and B4 = mahogany woods biochar). The dosage of biochar consists of four levels (D0 = control, D1 = 5 ton/hectare, D2 = 10 ton/hectare and D3 = 15 ton/hectare). The tested variable is being analysed by using analysis of variance (ANOVA). Findings The screen printing liquid waste polluted soil physical, chemical and biological characteristics analysis shows that the soil pH is neutral, a low C organic, a low N total, a high P, CEC and base saturation, while the texture is soft. The analysis results of rice hulls biochar physical, chemical and biological characteristics are quantitatively better in comparison with chicken manure biochar, coconut shell biochar and mahogany biochar. The quantitative application of rice hulls biochar15 ton/hectare dosage can increase the growth of mustard greens, and also, it recovers the soil characteristics by heavy metals total rate of 14.11 ppm Fe and 0.95 ppm Cr from the plant, while 209.05 ppm Fe and 4.12 ppm Cr were found in the soil. Originality/value This is one of few studies the biochar to screen printing liquid waste polluted lands. Currently, numerous kinds of chemical substances have been applied in a form of fertilizer and pesticide into the soil. Other activities like transporting the crop residues, and the contamination of irrigation water that is caused by screen printing liquid waste, have also affected the soil. It becomes degraded where the soil becomes compact and losses its nutrients, and it is containing heavy metals material that is toxic for plants. Biochar is applied into the polluted soil to improve the soil, which is hard to decompose and is long-lasting in the soil. These days, both the raw or ready food products are exposed to the heavy metals with a large and concerning number, especially in big cities which most of the soil is polluted.
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Ebba, Jonathan, Ryan W. Dickson, Paul R. Fisher, Crysta N. Harris, Todd Guerdat, and Sofia Flores. "Fertilizer and Plant Growth Regulator Strategies for Improving Consumer Performance of Container-grown Petunia." HortTechnology 31, no. 3 (2021): 304–14. http://dx.doi.org/10.21273/horttech04757-20.
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The overall goal was to evaluate fertilizer options for greenhouse producers, with or without a plant growth regulator (PGR) application, to improve subsequent performance of container-grown annuals. Petunia (Petunia × hybrida) was the model container-grown crop in simulated production and consumer environments. The first experiment at two locations (New Hampshire and Florida) compared strategies using water-soluble fertilizer [WSF (17N–1.8P–14.1K)], controlled-release fertilizers (CRF), and slow-release fertilizers (SRF) that were either applied throughout or at the end of the 8-week production phase [point of shipping (POS)] for petunia rooted cuttings grown in 8-inch azalea containers. In the subsequent simulated “consumer” phase, container plants were irrigated with clear water (no fertilizer) for 6 weeks. Plant performance [number of flowers, SPAD chlorophyll index, dry weight, and tissue nitrogen (N)] at the end of the consumer phase was improved by top-dressing at POS with either CRF or granular organic fertilizer (both at 2.74 g/container N), or preplant incorporation of either a typical CRF at 4.12 g/container N or a CRF with an additional prill coating to delay initial release (DCT) at 2.74 g/container. There was no carry-over benefit from applying a liquid urea-chain product (1.37 or 2.74 g/container N) or top dressing with granular methylene di-urea (2.74 g/container N), or 400 mg·L–1 N (0.2 g/container N) from a liquid organic fertilizer at POS. The consumer benefit of applying 400 mg·L–1 N (0.2 g/container N) from a WSF at POS was increased by supplementing with 235 mg·L–1 magnesium (Mg) and 10 mg·L–1 iron (Fe). A second experiment in 10-inch-diameter pots evaluated the effect on consumer performance from providing 200 or 400 mg·L–1 N of WSF with the PGR paclobutrazol, at the final 1 L/pot irrigation at POS. Application of 3 mg·L–1 paclobutrazol delayed leaf yellowing and reduced plant height, width, and shoot dry weight during the consumer phase, resulting in a more compact growth habit and higher plant quality compared with plants that received no PGR, regardless of WSF treatment. Addition of supplemental 235 mg·L–1 Mg and 10 mg·L–1 Fe to the high rate of WSF and PGR did not improve consumer performance compared with other treatments that included a PGR. Overall, the first experiment demonstrated that the most effective fertilizer strategies require a CRF or SRF that will release nutrients throughout the consumer phase, and that impact of liquid fertilizer options is limited because of lower N supply per container. A single application at POS of a high rate of WSF with supplemental Mg and Fe may have short-term benefits, for example while plants are in a retail environment. Growers should consider combining a residual fertilizer with a PGR application for premium, value-added container annuals.