Reduction In Water Requirement Research Articles

Influence of Super-Absorbent Polymer on Growth and Productivity of Green Bean under Drought Conditions

The water-retaining and yield-increasing capacity of super-absorbent polymer (SAP) are essential for soil remediation in arid and semi-arid areas. Water availability is an increasing challenge to plant development and crop yield. During the growing seasons in 2021 and 2022, the present study was conducted to evaluate the effect of the addition of different amounts of SAP on the development and yield of green beans (Phaseolus vulgaris L. cv Bronco) under varying water deficit stresses, compared with the control treatment without SAP and water deficit stress. The results demonstrated that a 50% reduction in water requirement (WR) resulted in significant decreases in leaf fresh weight, specific leaf area, leaf total chlorophyll content, pod number, leaf free water content, pod fresh weight per plant, and yield. Decreases were also found in pod total chlorophyll content, carotenoids, dry matter and total protein, leaf proline content, and crude fiber content. Additionally, leaf water saturation deficit was significantly increased under the stress compared with the full irrigation at 100% WR. However, irrigation at 75% WR increased pod contents of ascorbic acid, total sugars, and leaf bound water. The current study also indicated that addition of SAP significantly enhanced the above-mentioned growth characteristics under irrigation at 50% and 75% WR. Treatment with SAP at 3 g/plant was the most effective in mitigating the adverse effects of water deficiency, especially at the irrigation rate of 75% WR. Pearson’s correlation analysis showed significantly positive correlations between the growth parameters, as well as pod yield, under water stress and SAP. This study provides a promising strategy for green bean cultivation by adding SAP to soil to alleviate water shortage stress.

Change in free cyanide content of bitter cassava during incubation and drying and physical properties of dry-milled cassava flour

Cassava root contains cyanogenic glycosides that can undergo cyanogenesis and produce cyanide, which is hazardous to human health. Cassava starch is produced by wet-milling cassava, a good method for eliminating cyanogens. Nonetheless, the operation consumes considerable water and generates highly organic and acidic wastewater. For a more sustainable technique, dry milling can be used to conserve water and reduce waste. An alternative method for removing cyanogen must be investigated. This study aimed to determine the effect of incubation and drying temperatures on the concentration of free cyanide in cassava flour. Incubation for four hours increased the amount of free cyanide in fresh cassava cubes, which decreased thereafter. A 24-hour incubation lowered free cyanide by 30.5–53.7%. During the initial forty minutes of drying at varied temperatures (60, 70, and 80 °C), the free cyanide concentration increased dramatically before decreasing. Drying for four hours caused 53.6–78.5% reduction in HCN from the initial concentration before drying. The reduction rate and concentration of free cyanide in dry-milled cassava flour were not significantly changed by drying at different temperatures. Dry processing allows 70–90% reduction in water requirement.

A novel and economically viable agro-technique for enhancing productivity and resource use efficiency in menthol mint (Mentha arvensis L.)

Menthol mint (Mentha arvensis L.) is an important essential oil-bearing plant of the family Lamiaceae. Essential oil obtained from the leaves used in aromatherapy, flavour, and pharmaceutical industries. Producing the maximum essential oil yield with minimum use of resources to minimise the cost of cultivation and cropping period is need of the hour. Hence, the field experiment on menthol mint crop was carried out in two consecutive years (2015–2016) at the research farm of CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow. This research aimed to optimize the planting method, planting time, and plant density to enhance productivity and resource use efficiency. The experiment consisted of three planting methods, three time of planting, and four plant densities was conducted in split plot design with three replicates. Maximum essential oil yield of 209.8 kg ha−1, the minimum crop maturity period of 131 days, and lower water requirement of 86 cm was found under ridge bed planting method from two harvest. The crop planted in the month of February gave maximum net profits of $ 2669 ha−1 as compared with the crop planted in March and April months. Crop planted on ridges grown in the month of February with plant density of 166,666 plants ha−1 was found best combination for obtaining maximum essential oil yield, bringing about 30 days earliness in crop maturity and reduction in water requirement. The crop planted on ridges yields maximum essential oil per unit area and time, and this led to enhancement in resource use efficiency with significant improvement in net profits. Further, it provides an opportunity to have two harvests with minimum damage to the crop by excessive moisture availability during the early onset of monsoon.

Performance analysis of desalination system working on humidification-dehumidification coupled with solar assisted air heater and wind tower: Closed and open water cycle

The world which is hot and arid strives for fresh water and thermal comfort, thus there are two basic requirements. In this work, performance of wind tower in combination with solar air heater assisted humidification-dehumidification desalination system working with closed and open air water cycle is analysed numerically for cooling effect and fresh water production. The behaviour of system has been studied by different air flow rate in tower, temperature drop due to energy stored in wall and clay conduits, temperature drop due to evaporative cooling, humidity of moist air available for cooling, amount of potable water produced in dehumidifier and its variation with design and operating variables.A mathematical model based on fluid flow, heat transfer, energy and mass balance in components of system has been developed. Study reveals that comfort condition is achieved mainly by evaporative cooling in wind tower. Optimized column height is found as 8–9 m suitable to design the wind tower with 65% decrease in air velocity, 31% decrease in air temperatures and change in relative humidity up to 90%, however 42% reduction in water requirement in humidifier is also achieved at 5 m height with a cooling effect of 3.5 kW. Air mass flow rate of 0.032–0.035 kg/sec in solar air heater found suitable with maximum productivity of 5 and 4.2 kg/day for closed and open water cycle respectively. Water mass flow rate of 0.035–0.038 kg/sec in dehumidifier has been found suitable for 200% increase in productivity.

تاثیر کمآبیاری بر عملکرد و اجزای آن در هیبریدهای ذرت دانهای (Zea mays L.)

با توجه به کمبود آب و مصرف زیاد آب در هیبریدهای دیررس ذرت، بررسی رشد، عملکرد و مصرف آب در هیبریدهای این گیاه ضروری می باشد. از این رو به‌منظور بررسی اثرات کم‌آبیاری بر عملکرد و اجزای عملکرد هیبریدهای ذرت دانه‌ای، آزمایشی به صورت کرت‌های خردشده در قالب طرح بلوک کامل تصادفی با سه تکرار، طی دو سال زراعی 4-1393 اجرا شد. کرت‌های اصلی به سطوح آبیاری (100، 80 و 60 درصد نیاز آبی) و کرت‌های فرعی به هیبریدهای ذرت (شامل دو هیبرید دیررس(KSC705, KSC704)، دو هیبرید متوسط‌رس (KSC500, KSC400) و دو هیبرید زودرس((DC370, KSC260) تخصیص داده شدند. نتایج نشان داد که عملکرد و اجزای عملکرد همه هیبریدها در مواجهه با شرایط کم-آبی، به طور معنی‌داری کاهش یافت، به‌طوری که در سال اول در هیبرید KSC705 (دیررس) و هیبرید KSC400 (متوسط‌ رس)، کاهش آبیاری از 100 به 60 درصد نیاز آبی، کاهش حدود 20 درصدی عملکرد را به دنبال داشت. در صورتی که در هیبرید زودرس کاهش آبیاری از 100 به 60 درصد نیاز آبی کاهش چندانی در عملکرد ایجاد نکرد. در سال دوم کاهش آبیاری از 100 به 60 درصد نیاز آبی در هیبرید KSC705 (دیررس)، KSC400 (متوسط‌ رس) و DC370 (زودرس) به ترتیب منجر به کاهش 24، 28 و 24 درصدی عملکرد شد. برتری عملکرد در هیبریدهای دیررس متاثر از برتری صفاتی مانند ارتفاع بوته، تعداد ردیف بلال، تعداد دانه در ردیف، وزن 300 دانه، شاخص برداشت و عملکرد زیست‌توده بود، با وجود این با اعمال کم‌آبیاری شدید، این برتری در بین هیبریدها معنی‌دار نبود. لذا به نظر می رسد که بتوان هیبریدهای دیررس را برای مناطق بدون محدودیت آب و هیبریدهای متوسط‌رس را برای شرایط با محدودیت آب استفاده کرد.

Investigation of seed germination of twelve Mediterranean wildflowers for evaluating their potential use on extensive green roofs

The use of native plants in an urban context can have positive impacts, such as the reduction of water requirement, management costs, increasing urban biodiversity, and the safeguard of germplasm. This study evaluated the germination capacity of twelve native Mediterranean wildflowers aiming to be utilized for extensive green roofs. Some of the taxa (Antirrhinum majus subsp. tortuosum, Dianthus sylvestris, Lobularia maritima, Ruta chalepensis) have not been previously investigated. Seeds of native plants were collected in Italy, and quantitative analyses on seed germination in light or darkness conditions were carried out. For every taxa, mean germination time (MGT) and germination percentage were determined. The taxa differed markedly in their germination percentage and times. The results were generally concordant with previous research, and in particular for Armeria pungens, Clinopodium nepeta and A. majus. However, some differences were also observed for Helichrysum italicum subsp. microphyllum and Prasium majus, and distinct differences for Anthemis maritima and Glaucium flavum. Finally, A. majus, D. sylvestris and G. flavum (in darkness) showed high germination percentage, low MGT and limited requirement of pre-seeding treatments. Further research is needed to assess germination performances and success while scaling-up from laboratory to greenhouse to outdoor field conditions.

Sustained Deficit Irrigation and Mulching on Growth of Sourani Olive Trees in Kuwait

Olea europaea, a native plant of the Mediterranean region, is of great interest to agronomists worldwide, owing to its health beneficial properties and tolerance to harsh environmental conditions, along with its economic importance. The productivity and production efficiency of olive is linearly related to both the level of transpiration and the amount of water supplied. Under conditions of limited supply of good quality water for irrigation in Kuwait, deficit irrigation applied at selected phenological stages can maximize economic gains and minimize environmental damage. Moreover, mulching contributes to a significant reduction in water requirements via reducing soil water losses and increasing soil water retention. In this study, the effects of different irrigation levels, a restitution of 50%, 75% or 100% of the estimated evapotranspiration rate (ETc), and the application of mulching on plant growth under the Kuwait environmental conditions were determined to evaluate the possibilities of reducing the amounts of water supplied with irrigation. Various parameters determining the vegetative growth of the trees such as average height, stem girth and number of branches were recorded at three months intervals. Both the irrigation level and mulching were shown to possess a significant impact on growth of Sourani olive cultivar under the Kuwait environmental conditions. Statistical analysis revealed no significant difference in the height of the trees under all the three irrigation treatments with mulch and trees under 100% ETc devoid of mulch. In contrast, a significant difference was exhibited by trees under 100% ETc with mulch and 50% ETc without mulch. Within each irrigation treatment, trees with mulch presented higher values for plant height, stem girth and number of shoots. Thus deficit irrigation of 50% ETc along with organic mulch was shown to enhance vegetative growth close to its maximum potential by conserving the scarce water resources.

Technical adaptations for mechanized SRI production to achieve water saving and increased profitability in Punjab, Pakistan

Even in a country with a large population and rapid population growth, there can be labor shortages in the agricultural sector, because of outmigration of the able-bodied work force. The System of Rice Intensification (SRI) is not necessarily more labor-intensive once the methods have been learned, but the initial labor requirements can be a barrier to adoption, and farmers with large land areas cannot find the labor needed to use these more productive methods. Recognizing this problem, a set of agricultural implements have been designed for mechanizing the operations of SRI, with a view to reducing water requirements as well as labor requirements because the current conditions for agricultural production in the Punjab region of Pakistan include water scarcity and poor water quality as well as labor shortages. This article reports on the process of mechanizing SRI production in Punjab, which has been quite successful so far. Average yield is considerably increased with a 70% reduction in water requirements and a similar reduction in labor needs. The machinery and methods have been further adapted to other crops, being grown on permanent-raised beds, so that SRI with organic fertilization is combined with Conservation Agriculture. This combination is referred to as “paradoxical agriculture” because it enables farmers to achieve higher outputs with reduced inputs.

Exploitation results of seven RO plants for recovery and reuse of treated effluents in textile industries

The paper comprises a case study on the implementation of the advance treatment process (ATP) in seven small-scale textile industries. The ATPs installed and commissioned are in compliance with the Statutory Board directions for recovery and reuse of treated effluent leading to zero effluent discharge. The textile effluents are treated in effluent treatment plants comprising a physicochemical option followed by biological activated sludge process, pressure sand filtration and activated carbon adsorption. The tertiary treated effluents (25–65 m 3/d) are high in total dissolved solids, chlorides and hardness, and partly reused for washing screens, cloth and ash quenching. The tertiary treated effluent contained suspended solids and total dissolved solids in the range, 4–30 mg/L and 1980–2682 mg/L, respectively, with COD concentrations in the range, 125–410 mg/L and did not meet the stipulated standards for discharge into inland surface waters. A part of the tertiary treated effluent (4.0–9.5 m 3/d) is routed to ATP for recovery of boiler feed quality water. The ATP comprises a multi-grade filter, ultrafiltration (UF) unit and a reverse osmosis (RO) unit. The multi-grade filter ensured complete removal of suspended solids with a marginal decrease in COD. The fouling index (b) for the feed to the ultrafiltration was estimated to be varying in the range 0.6–2.1× 10 −3 s −1.The UF operated at 200–300 kcals with 88–95% permeate recovery. This unit achieved 80–90% removal of BOD and COD and 65–90% removal of phosphates. The RO unit at a pressure range of 1270–1670 kPascals produced 68–84% permeate. The permeate characteristics conforms the boiler water quality as prescribed by the Indian Standards Institution for low-pressure drum type boilers. The pH of the recovered water was adjusted with alkali to pH 10–11 and mechanically deaerated for use in boilers. Recycle/reuse of tertiary treated effluents for various purposes and reuse of the recovered water from advance treatment process as boiler water make-up has resulted in a reduction in water requirements by 30–35% in each industry.

Generalization of Flow Behavior of Cement‐Fly‐Ash Pastes and Mortars

A simple method to optimize the level of cement replacement by fly ash in cement—fly‐ash mortar and concrete is proposed. The method is based on flow‐table tests. In this test, for any specific level of flow a decrease in water content of the mix increases the number of drops. The lines representing water content of the mixes and the logarithm of the number of drops are called flow lines. As the replacement of cement by fly ash is increased in any mix, there is a progressive reduction in water requirement to cause some percentage flow. The slopes of the flow lines gradually decrease with increasing fly‐ash content. Normalization water content, w, of the flow lines, with respect to water content corresponding to 25 drops, w25, leads to collapse of the flow lines into a unique line. This establishes a functional relationship between w/w25 and the number of drops. Using this relationship, the flow line of any mix can be predicted if the value of number of drops for any arbitrary water content is known. This procedure reduces the number of trials required to optimize the level of cement replacement by fly ash.

Bond Effects in High-Strength Silica Fume Concretes

The strengthening effects in high-strength silica-fume concretes were evaluated in terms of water-reducing effect associated with the reduction in water requirement in the silica fume system and in terms of an inherent effect that reflects the increase in strength of the silica-fume concrete over a similar water/cement ratio concrete without silica fume. The inherent effect was found to be as important as the water-reducing effect, and it is suggested that its origin is in the improved aggregate-matrix bond. This enhanced bonding is associated with the formation of a dense microstructure in the transition zone of the silica-fume concrete.

Calculating Effectiveness of Water Conservation Measures

Implementation of water conservation programs can result in significant savings to water utilities. Engineers and planners working with utilities need to be able to predict the reduction in water requirements (i.e., effectiveness of water conservation) that will result from implementation of water conservation measures. A procedure that was developed to help predict water conservation effectiveness for typical conditions is presented.

High-Range Water-Reducing Admixtures in Precast Concrete Operations

The minimum acceptable reduction of water requirement is proposed to be 12 percent, incontrast to a minimum acceptable reduction of water requirement of 5 percent for chemical admixtures Types A, D, and E (conventional water-reducing admixtures). Two classes of high-range., water-reducing admixtures are proposed, namely, Types F and G, denoting normal-setting and retarding admixtures, respectively. ented as a concrete admixture as early as 19351 Nevertheless, they did not come into real commercial use until the 1960s. They have been used in Japan for about 15 years and in Western Europe3 for nearly 10 years. A few other countries such as Australia4'5 have also used them commercially (especially in the precast concrete industry) producing apparently favorable results. H-R admixtures have been used in North America for only about 5 years and to a much lesser extent than in Europe or Japan. Nevertheless, they have been found particularly advantageous in precast concrete applications. In addition to improving the workability of the concrete mix and the attainable compressive strength of the product, H-R admixtures substantially reduce the time required to achieve stripping strengths. This, of course,