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Water Productivity Journal - Volume:2 Issue: 3, Summer 2022

Water Productivity Journal
Volume:2 Issue: 3, Summer 2022

  • تاریخ انتشار: 1401/07/30
  • تعداد عناوین: 6
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  • M More, Pooran Pragnya, Gulja Nair *, K Raneesh, Anitha V C Pages 5-16
    Introduction
    With the limited scope of development of irrigation potential, rain water management plays an important role to supplement the surface water for domestic, irrigation and industrial uses. Therefore, efficient conservation and scientific management of harvested water is crucial for optimum utilization for crop production. Soil and water conservation structures create temporary storage of water and help in groundwater recharge.
    Materials and Methods
    Watershed is geographical area that drains to a common point, which makes it an attractive unit for technical effort to conserve soil and maximize the utilization of surface and subsurface water for crop production. The research was carried out during 2015-16 at Raholi watershed (602 ha) of Maharashtra state of India. The Raholi watershed is situated in Hingoli district of Marathwada region, which is 9 Km away from Hingoli city. It is located at 19⁰70’ N latitude and 77⁰07’ E longitude. The watershed has been developed by Department of Agriculture, Government of Maharashtra in the year 2010-11. Different soil and water conservation structures namely graded bunds, earthen nala bund, cement nala bunds and continuous contour trenches were undertaken in the watershed. Representative soil and water conservation structures were selected to study their effect on reducing soil erosion and soil loss in the area. On an average reduction in cross sectional area of graded bund was found to be 29.46 per cent (23.81 to 35.71 per cent) over a period of four years after their construction.
    Results
    On an average reduction in cross sectional area of Continuous Contour Trenches (CCT) was found to be 39.61 per cent (33.33 to 64.71%) over a period of four years after its excavation. Reduction in cross sectional area of earthen nala bunds was found 19.14 per cent over a period of four years after their construction where as its storage capacity reduced by 3.91 per cent for the same period. No change in the dimension of three cement nala bunds was found at the post development stage of the watershed. Reduction in the storage capacity of the cement nala bunds was found in range to be 2.43 to 4.50 per cent over a period of four years after their construction.
    Conclusions
    It can be concluded that average depth and area of silt deposited at different Cement nala bunds (CNB) including CNB 1, CNB 2, CNB 3 were 0.13, 0.16 and 0.15 m and 1073.25, 746.32, 510.00 m2 respectively. The weight of silt deposited at CNB 1, CNB 2 and CNB 3 were found to be 184.16, 157.62 and 100.98 tonnes respectively. The total silt deposited in all cement nala bunds was found to be 442.76 tonnes during the period of four years after their construction. The per cent reduction in storage capacity of CNB 1, CNB 2 and CNB 3 was found to be 2.43, 2.79 and 4.5 per cent respectively over the period of four years from their construction. The reduction of storage capacity was due to deposition of silt in the nala on the upstream side of these cement nala bunds.
    Keywords: Watershed, Bunds, Trenches, Soil erosion, Storage capacity, Water conservation
  • Matthew Ibitoye, Adebayo Eludoyin *, Babatunde Fafunwa, Lateef Opoola Pages 17-36
    Introduction
    Developing countries, including Nigeria and many other sub-Saharan Africa are still developing programs that tend to encourage or provide growth poles factors, such as institutions, planned cities, and conversion of a settlement to administrative centers with the intention of attracting population increase through immigration. The growth pole areas often become nuclei for urban development in any of the three main models of urban development. One of the parts of the environment that become affected by urban development is the river basin, often due to competition with space for built-up areas, a situation that is often exacerbated by population increase and climate variability. A river basin is a defined unit area with topographic, hydraulic and hydrological unity; which can also be referred to as an identifiable planning region. Poorly monitored and controlled urban growth is a threat to the riparian ecosystems in many developing countries. Studies have shown that data availability is a major challenge to understand the impact of such growth on drainage basins. As at early 1990s when the study area became the administrative capital of a state (Ondo), its population surged due to migration because of the focus of government to establish their ministries and agencies in the new capital city. The National Population Commission reported 4% population increase in the study area, and as such, pressure on previously unoccupied and protected areas becomes unexpected. Studies in Islamabad, Pakistan and in North-West Delhi, India also indicated increase in built-up areas around protected areas and within drainage basins due to population increase into administrative capital cities.
    Materials and Methods
    This study examined the extent of urban growth and the impact on a river basin in one of the administrative capital cities in southwestern Nigeria, using freely available Landsat datasets. Specific objectives were to assess vegetal and topographic changes in the status of riparian vegetation and other land cover, as well as the impact of urban growth on the river basin. Data included multi-date Landsat images.
    Results
    The Ala River in Akure, southwest Nigeria, whose vulnerability was investigated in this study, has experienced a reduction in basin area and parts that were previously classified as water bodies were later overgrown by built-up and related human activities. Physical observation of the river plain reveals that apart from bridges that were constructed to ease road transportation across the river, no important event was available to protect the basin from intrusion and attendant exploitation, at the time of the surveys. The former studies have argued for the protection of flood plains, noting that areas close to the plains are vulnerable to flood disasters. Building regulations that include the set-back rules around major rivers are rarely observed due to compromised implementation strategies that typically discouraged non-biased enforcement. In addition, parts of the downstream station of the river have been converted to dumpsites and the hitherto perennial streams in the area have either become intermittent or dried off. Also, an increase in surface temperature as well as increased built-up areas within the basin may be associated with the dryness of some of the river tributaries. In general, the wetland ecosystem in the study area has given way to poorly planned built-up and few shanty settlements. Results showed increase in built-up areas (48.1%), decline in vegetal cover (71.2%), loss of vegetal greenness (< -0.33) and increased land surface temperature (0.23-0.25oC).
    Conclusions
    The study concluded that the Landsat images with ground surveys can provide reliable results for ecosystem monitoring in the area. Conscious sustainable urban planning and strategies for the sustenance of the urban wetlands as well as policy towards urban greening are recommended. Future studies will be focused on t hydro-morphometric analysis of the river basin.
    Keywords: Akure, Southwest Nigeria, Drainage Basin, Landcover change, Land surface Temperature, Urban Growth, Impervious surface, Water productivity
  • Mohammed S * Pages 37-44
    Introduction
    Meeting the food and fibre demands of a growing global population is a considerable challenge. To date, irrigated agriculture has been responsible for 40% of the total food and fibre production whilst using only 18% of world’s arable land, Irrigation requirements, however, account for nearly 70% of the world’s total freshwater withdrawals and have significantly altered hydrological and environmental conditions in both surface and subsurface water resources. This has generated criticism and debate about the (un) sustainability of irrigated agriculture. Irrigation managers must often justify the use, efficiency and productivity of water in competition and comparison with other uses and users. The challenge is to enhance water allocation decisions to reduce negative environmental impacts, whilst continuing to satisfy food and fibre demands. Research and investments have been oriented towards applying cost effective technology, precision agriculture, and environmentally friendly techniques to pursue sustainable water use in agricultural development. Rain Hose is affordable spray irrigation technology. Its replacement for Sprinkler Irrigation System. It's easy to install and maintain. Rain Hose is flexible hose with pattern of drip holes. These drip holes are made with nano punching technology to ensure uniform flow of water. Rain Hose is suitable for closely spaced crops, onion, vegetable crops, leafy vegetables, groundnut etc. Rain Hose is an affordable spray irrigation technology. It is a replacement for the sprinkler irrigation system. It is easy to install and maintain. Rain Hose is a flexible hose with a pattern of drip holes. These drip holes can be made with nano punching technology to ensure a uniform flow of water. The rain hose is suitable for closely spaced crops like onions, vegetable crops, leafy vegetables, groundnuts, etc. Rain hose is an emerging irrigation technique which is widely used for closed spaced crops. It is an alternative to the sprinkler irrigation but both are adopting the spraying technology. The spraying pattern in the rain hose irrigation will be linear on either sides up to the full stretch of the rain hose. Variation in the spray width and the discharge of water from the nozzles of rain hose under different flow rates are studied for various available diameters of rain hose. There is no standard available on the optimum combination of length and diameter of rain hose. A Catch-can method based field test was conducted to estimate the influence of length and diameter of rain hose for four flow rates and the pressure values through the main pipe viz., were noted down.
    Materials and Methods
    A rain hose of five diameters 20mm, 32mm, 40mm, 50mm, and 63mm were attached to the main pipe individually using proper setup and the spray width and discharge through the nozzles were measured for every 20m interval. The 2end coupler is connected with the main pipe and the other end is sealed shut, making sure that the water flows through the main hose in the desired pressure. The rain hose is attached laterally to a main PVC pipe of 63mm diameter, where the connection is made by the help of 4-way couples. The end of the rain hose is closed with an end cap. A 5HP open-well motor of type TMH4H is used, wherein the discharge capacity is 33, 120 litres per hour. Regulating valves and Reducers are used to control the flow of water in the system. The standard wall thickness of all the above used rain hoses are 350 microns. The field test conducted, is conducted at an interval of 20m from the main pipe where the total discharge of the water and the width of spraying in between the interval points are obtained for the rain hoses of the above mentioned diameters, as a result of which the effective laying length of the rain hose is evaluated by considering the reduction in water discharge and spraying width, in each types.
    Results
    For every 20m intervals, the corresponding spraying width and the water discharge in between the intervals for various diameter rain hose are graphically represented. The results of this study can be of great help to researchers in the purposeful application of precipitation-runoff and timely management of water resources.
    Conclusions
    These results are obtained in Coimbatore. There will be chances of slight deviation in the results based on other environmental condition. There will be a maximum possibilities of water leakage if joints are increased and it has to meet the pressure fluctuations throughout the length of the rain hose.
    Keywords: Spray Width, Rain hose, Discharge, Length of Laterals
  • Mohadeseh Madadi *, Ramin Jafari, Khosro Karimi, Mousa Maleki Pages 45-62
    Introduction
    Persian garden is an architectural combination of solids and plants, a living component that reflects the culture of Persian nation and regional climate situations. The main structure of all of the world’s historical gardens are based on the nature and architecture or the method of combining plants, water and buildings that organize the body to create a suitable space for human life. What distinguishes the gardens as a cultural and natural heritage from other places is the conceptual layers of the meanings as well as physical and functional characteristics.
    Materials and Methods
    The purpose of this study is the optimal use of water in Persian gardens and according to the previous and present works with a combination of the modern innovations such as constructed wetlands and hydroponic greenhouses that attempt to use an optimal amount of water by reusing it in these gardens.
    Results
    There are two direct and indirect ways to improve water efficiency. There are three direct ways to improve productivity: I. Increasing the deduction form without changing the amount of water consumed. In this way, the fractional face increases without reducing the amount of water used. Improving the fertilizer program (feeding), changing the cultivar, improving crop management are solutions that reduce water consumption, will increase the face of the fraction and thus improve the efficiency of water. II. Reducing the denominator of the fraction means implementing a program to reduce applied water by recognizing the physiological behavior of plants, recognizing useless uses and making arrangements to control them, modifying agricultural operations to reduce water consumption such as modifying the planting date, changing cultivation methods such as transplanting, modification cultivation arrangement, modification of irrigation method. III. Integrated method, in the sense that at the same time as decreasing the denominator of the fraction, the form of the fraction also increases. In this strategy, recognizing the useless uses, recognizing the physiological behavior of the plant, modifying the irrigation method along with modifying the management of fertilizer consumption and agricultural operations are cases that will lead to reduce the denominator and increasing the fraction. The indirect method basically deals with processes that, although very important and for which different inputs are used, but are not considered. Crop losses from harvest to consumer consumption, energy losses of agricultural and irrigation machines, leaching of fertilizers and damage caused by agricultural hazards are among the cases of loss of agricultural products. Obviously, the use of potash fertilizers can increase the crop resistance to frost or the use of blowers, irrigation, windbreaks, and other methods of dealing with agricultural hazards, will be effective in reducing damage and thus production productivity will increase. Constructed wetland and hydroponic system have been used in this research and have increased the water productivity.
    Conclusions
    This research has been accomplished by a descriptive-analytical method and field observation to improve the water productivity in Persian gardens and proposing a suitable plan for theses gardens in the semi-arid city of Esfahan. The first prerequisite for achieving water saving is the correct knowledge and understanding of the definitions and interpretations in the field of sustainable use of water, that is, to use correct and meaningful concepts. In the first step, a distinction must be made between "water use" and "water consumption". In order to identify and select technical and effective economic solutions on water demand and consumption management in each catchment, a regular system and framework of "water accounting" should be established. Instead of paying much attention to the development of pressurized irrigation in the country, more attention should be paid to other farming methods that reduce water consumption in agriculture. A Hybrid use of constructed wetland and hydroponic system in urban botanic garden could certainly overcome the water scarcity in semi-arid and arid regions such as Esfahan.
    Keywords: Persian Garden, irrigation, Esfahan, Water efficiency, Water productivity
  • Zareena Begum Irfan *, Nitesh Ahuja Pages 63-82
    Introduction
    The UN SDGs are a collection of 17 global goals set in 2015 by the United Nations General Assembly intended to be achieved by 2030. Ensuring universal and equitable access to safe and affordable drinking water for all by 2030 is the target outlined by SDG 6.1. The indicator for measuring the same is the proportion of population using safely managed drinking water services. In 2017, only 71 per cent of the global population used safely managed drinking water, an increase from 61% in 2000, leaving 2.2 billion people without safely managed drinking water, including 785 million without even basic drinking water. Also, in 2017, 90% of the world’s population (6.8 billion people) used at least basic drinking water services, rising from 82% (5 billion people) in 2000. It is estimated that at this rate, global coverage would be around 96% still following short of the universal access. This goal is far from being realized in the case of the Indian subcontinent which accounts for approximately 17.8% of the world population. As per international standards, a country with per-capita water availability less than 1700 m3 is categorized as water stressed. According to the 2011 census India had a per capita water availability of 1543m3 which is projected to further decline to 1401m3 by 2025. Also India has a water stress score of 4.12 on a scale of 0-5 provided by the World Resources Institute. Moreover, there exists huge inequality in the distribution of access to water across states as well as difference strata of the population.
    Materials and Methods
    This paper uses household survey data from India to determine factors which outline the choice of drinking water source. We use the definitions from the World Health Organization (WHO) and divide the water sources into 3 broad categories: piped, improved and unimproved. It is a large-scale, multi-round survey conducted in a representative sample of households throughout India. The dataset comprises of 601, 509 households with around 699, 686 individuals. The survey has detailed information on various indicators like child mortality, nutrition indicators as well as characteristics of household members, household wealth and assets, location of source of water, person collecting water et cetera.
    Results and Discussion
    The results highlight that household income is an important determinant and positively affects the choice of a better water source. Other significant factors include gender and schooling of household head. While for number of women of age group 15-49, there is clear trend throughout, having positive association with choosing an improved water source and negative association with choosing an unimproved water source, the number of men in the age group 15-59 is negatively associated with choosing an improved water source in rural areas but not significant for any water source when looked at urban India. Policies that augment household income could provide for a better source of drinking water. The wealth effect appears to be larger for urban India. The majority of water collection is done by women and girl child and thus any benefits from investments in such policies will be greatest for this segment of the population. Since the data shows around 10% of the households to be still using unimproved drinking water sources, India as a long way to go so that it is able to achieve the target of safe drinking water for all by 2030.
    Conclusions
    Education of household head is seen to be positive and significant with using a piped water connection when looking at India as a whole. Higher educational attainment means more empowerment and knowledge of the best health practices. Individuals feel powerless when they have limited opportunity to bargain owing to low levels of education. Educated heads realise the potential health benefits of improved quality of water, especially for women and girls. It also plays important role in children’s school performance as fewer illnesses mean reduced absenteeism and dropout rates.
    Keywords: Water source, Improved, India, Rural, urban
  • Abeba Selie, Abebech Beyene *, Ashebir Tefera, Sisay Assres Pages 83-108
    Introduction
    Water management practice that is, deficit irrigation (DI) has a greater contribution to water-saving and increase crop water use efficiency (CWUE). DI is an approach where crops are exposed to a certain level of water stress either during a specific crop growth stage or in the course of the entire developing season. Furrow irrigation system requires a lower initial investment than other water application systems. However, it is usually associated with considerable runoff and excessive filtration at the upper portion of the furrow while it also causes insufficient application at the lower fields. The DI level to improve water productivity range is between 60 to 100% of full crop evapotranspiration (ETc) needs in previous works. Enhancing water use efficiency of irrigated crops through field irrigation management is vital in water-scarce areas. The DI and furrow irrigation systems are alternatives to enhance CWUE in such areas.
    Materials and Methods
    This experiment has been executed in Jawi district of Amhara location. Jawi district is found at 602 km North West of Addis Ababa with a geographical location of 36o 29’17.58’’ longitude and 11o 33’22.68’’ latitude. It is characterized with hot to humid climate of low land area with high unimodal rain fall (1250 mm) from May to October. Jawi district is located in the lowland part of Awi zone and its altitude ranges from 700 to 1500 m.a.s.l with mean yearly temperature of 16oC to 32oC. The climate of Jawi is Kola according to Ethiopian agro ecological climate classification and is equivalent to hot humid climate. The average annual potential evapotranspiration of Jawi is 5.52 mm day-1. A field experiment was worked out in Jawi district of Amhara region of Ethiopia with the objective of investigating the performance of various furrow irrigation techniques and DI levels to enhance the grain yield and CWUE of soybean. Split-plot design with RCBD arrangement in 3 replications was used and contains 3 furrow irrigation methods (Conventional Furrow Irrigation (CFI), Alternative Furrow Irrigation (AFI), and Fixed Furrow Irrigation (FFI)) as main plot and three DI levels (100%ETc, 75%ETc, and 50%ETc) as sub-plot.
    Results
    The result showed that DI had a significant effect on soybean above ground biomass and a very high significant (P<0.001) effect on grain yield. The advanced grain yield of 1944 kg/ha was obtained from CFI at 100% of ETc and the minimal one was recorded in FFI at 50% ETc. The highest CWUE of 1.17 kg/m3 was obtained from AFI at 100% ETc. The highest yield reduction in this experiment was obtained at AFI at 100% of the crop water application which showed 7.46% yield reduction and also saved 47.9% irrigation water as compared to CFI. Using this saved water, 35% grain yield was obtained under an AFI compared to CFI.
    Conclusions
    It could be reported that enhanced water saving and CWUE might be achieved using 100% ETc at AFI system solving water shortage problem. It can be concluded that, in areas where water is scarce alternative furrow irrigation saves 50% irrigation water in comparison to conventional furrow irrigation method. Hence, additional land could be irrigated with the saved irrigation water in similar water scarce areas. This finding could make certain the possibility of irrigation improvement in the study area and other comparable agro-ecology like the study area.
    Keywords: Water Productivity, Crop water use efficiency, Deficit irrigation, Furrow irrigation systems, soybean