The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Dhiraj Khalkho - One of the best experts on this subject based on the ideXlab platform.
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An Unsteady Subsurface Drainage Equation Incorporating Variability of Soil Drainage Properties
Water Resources Management, 2014Co-Authors: Ashok Kumar Pali, Praful Katre, Dhiraj KhalkhoAbstract:Almost all unsteady Subsurface Drainage equations developed so far use constant value of drainable porosity and hydraulic conductivity which may not be representative of entire Drainage flow region. A Drainage equation was, thus, developed incorporating depth-wise variability of drainable porosity (f) and hydraulic conductivity (K) of saline soils of Haryana state in India. The drain spacing with measured hydraulic heads at different periods of Drainage were estimated by the developed equation and compared with the corresponding drain spacing estimated by commonly used unsteady Drainage equations. The study revealed that the developed equation estimated the drain spacing that was nearest to the actual drain spacing of the existing Subsurface Drainage system, when a generally used design criterion of 30 cm water table drop in 2 days is considered. For a criterion of desired water table drop in 3 days and beyond, Glover equation was found to be the most superior. Hence, both the developed equation and Glover equation can be readily used with the associated design criteria for designing unsteady Subsurface Drainage systems in saline soils of the state of Haryana, India.
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An Unsteady Subsurface Drainage Equation Incorporating Variability of Soil Drainage Properties
Water Resources Management, 2014Co-Authors: Ashok Kumar Pali, Praful Katre, Dhiraj KhalkhoAbstract:Almost all unsteady Subsurface Drainage equations developed so far use constant value of drainable porosity and hydraulic conductivity which may not be representative of entire Drainage flow region. A Drainage equation was, thus, developed incorporating depth-wise variability of drainable porosity (f) and hydraulic conductivity (K) of saline soils of Haryana state in India. The drain spacing with measured hydraulic heads at different periods of Drainage were estimated by the developed equation and compared with the corresponding drain spacing estimated by commonly used unsteady Drainage equations. The study revealed that the developed equation estimated the drain spacing that was nearest to the actual drain spacing of the existing Subsurface Drainage system, when a generally used design criterion of 30 cm water table drop in 2 days is considered. For a criterion of desired water table drop in 3 days and beyond, Glover equation was found to be the most superior. Hence, both the developed equation and Glover equation can be readily used with the associated design criteria for designing unsteady Subsurface Drainage systems in saline soils of the state of Haryana, India. Copyright Springer Science+Business Media Dordrecht 2014
Ashok Kumar Pali - One of the best experts on this subject based on the ideXlab platform.
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An Unsteady Subsurface Drainage Equation Incorporating Variability of Soil Drainage Properties
Water Resources Management, 2014Co-Authors: Ashok Kumar Pali, Praful Katre, Dhiraj KhalkhoAbstract:Almost all unsteady Subsurface Drainage equations developed so far use constant value of drainable porosity and hydraulic conductivity which may not be representative of entire Drainage flow region. A Drainage equation was, thus, developed incorporating depth-wise variability of drainable porosity (f) and hydraulic conductivity (K) of saline soils of Haryana state in India. The drain spacing with measured hydraulic heads at different periods of Drainage were estimated by the developed equation and compared with the corresponding drain spacing estimated by commonly used unsteady Drainage equations. The study revealed that the developed equation estimated the drain spacing that was nearest to the actual drain spacing of the existing Subsurface Drainage system, when a generally used design criterion of 30 cm water table drop in 2 days is considered. For a criterion of desired water table drop in 3 days and beyond, Glover equation was found to be the most superior. Hence, both the developed equation and Glover equation can be readily used with the associated design criteria for designing unsteady Subsurface Drainage systems in saline soils of the state of Haryana, India.
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An Unsteady Subsurface Drainage Equation Incorporating Variability of Soil Drainage Properties
Water Resources Management, 2014Co-Authors: Ashok Kumar Pali, Praful Katre, Dhiraj KhalkhoAbstract:Almost all unsteady Subsurface Drainage equations developed so far use constant value of drainable porosity and hydraulic conductivity which may not be representative of entire Drainage flow region. A Drainage equation was, thus, developed incorporating depth-wise variability of drainable porosity (f) and hydraulic conductivity (K) of saline soils of Haryana state in India. The drain spacing with measured hydraulic heads at different periods of Drainage were estimated by the developed equation and compared with the corresponding drain spacing estimated by commonly used unsteady Drainage equations. The study revealed that the developed equation estimated the drain spacing that was nearest to the actual drain spacing of the existing Subsurface Drainage system, when a generally used design criterion of 30 cm water table drop in 2 days is considered. For a criterion of desired water table drop in 3 days and beyond, Glover equation was found to be the most superior. Hence, both the developed equation and Glover equation can be readily used with the associated design criteria for designing unsteady Subsurface Drainage systems in saline soils of the state of Haryana, India. Copyright Springer Science+Business Media Dordrecht 2014
Praful Katre - One of the best experts on this subject based on the ideXlab platform.
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An Unsteady Subsurface Drainage Equation Incorporating Variability of Soil Drainage Properties
Water Resources Management, 2014Co-Authors: Ashok Kumar Pali, Praful Katre, Dhiraj KhalkhoAbstract:Almost all unsteady Subsurface Drainage equations developed so far use constant value of drainable porosity and hydraulic conductivity which may not be representative of entire Drainage flow region. A Drainage equation was, thus, developed incorporating depth-wise variability of drainable porosity (f) and hydraulic conductivity (K) of saline soils of Haryana state in India. The drain spacing with measured hydraulic heads at different periods of Drainage were estimated by the developed equation and compared with the corresponding drain spacing estimated by commonly used unsteady Drainage equations. The study revealed that the developed equation estimated the drain spacing that was nearest to the actual drain spacing of the existing Subsurface Drainage system, when a generally used design criterion of 30 cm water table drop in 2 days is considered. For a criterion of desired water table drop in 3 days and beyond, Glover equation was found to be the most superior. Hence, both the developed equation and Glover equation can be readily used with the associated design criteria for designing unsteady Subsurface Drainage systems in saline soils of the state of Haryana, India.
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An Unsteady Subsurface Drainage Equation Incorporating Variability of Soil Drainage Properties
Water Resources Management, 2014Co-Authors: Ashok Kumar Pali, Praful Katre, Dhiraj KhalkhoAbstract:Almost all unsteady Subsurface Drainage equations developed so far use constant value of drainable porosity and hydraulic conductivity which may not be representative of entire Drainage flow region. A Drainage equation was, thus, developed incorporating depth-wise variability of drainable porosity (f) and hydraulic conductivity (K) of saline soils of Haryana state in India. The drain spacing with measured hydraulic heads at different periods of Drainage were estimated by the developed equation and compared with the corresponding drain spacing estimated by commonly used unsteady Drainage equations. The study revealed that the developed equation estimated the drain spacing that was nearest to the actual drain spacing of the existing Subsurface Drainage system, when a generally used design criterion of 30 cm water table drop in 2 days is considered. For a criterion of desired water table drop in 3 days and beyond, Glover equation was found to be the most superior. Hence, both the developed equation and Glover equation can be readily used with the associated design criteria for designing unsteady Subsurface Drainage systems in saline soils of the state of Haryana, India. Copyright Springer Science+Business Media Dordrecht 2014
John Hornbuckle - One of the best experts on this subject based on the ideXlab platform.
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Improving Subsurface Drainage design: minimising the environmental impacts
Australasian Journal of Water Resources, 2005Co-Authors: John Hornbuckle, Evan W. Christen, R. D. FaulknerAbstract:AbstractThis paper addresses how the design of Subsurface Drainage systems impacts on the Drainage volume and salinity of Drainage water generated. The effects of drain depth and spacing are reviewed and discussed. The conceptualisation of a Subsurface Drainage system which incorporates Drainage water quality into the design is presented. This system, known as a Multi-Level Drainage System, aims to minimise offsite impacts associated with Subsurface Drainage while still providing adequate protection from waterlogging and salinity of the plant root zone. This is achieved through the use of a shallow closely spaced Drainage system (0.7 m deep at 3.3 m) underlain by a deeper, widely spaced Drainage system (1.8 m deep at 20 m). Field investigations show that the shallow drains had approximately five times lower salinity than deep drains, with median values being 5.5 dS/m and 28 dS/m respectively. The results indicate that, by re-thinking Subsurface Drainage design to incorporate water quality aspects, alterna...
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Improving Subsurface Drainage Design - Minimising the Environmental Impacts
2004Co-Authors: John Hornbuckle, Evan W. Christen, R. D. FaulknerAbstract:This paper addresses how the design of Subsurface Drainage systems impact on the Drainage volume and salinity of Drainage water generated from these systems. The effects of drain depth and spacing are discussed along with the conceptualization of a Subsurface Drainage system which incorporates Drainage water quality into the design. This system, known as a Multi-Level Drainage System, aims to minimise offsite impacts associated with Subsurface Drainage while still providing adequate protection from waterlogging and salinity of the plant root zone. This is achieved through the use of a shallow intensely spaced Drainage system underlain by a deeper, widely spaced Drainage system. The results indicate that by re-thinking Subsurface Drainage design to incorporate water quality aspects alternative designs can be formulated which begin to meet the present day environmental constraints placed on Subsurface Drainage systems.
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Automated Subsurface Drainage Management System to Reduce Costs and Downstream Environmental Impact
2004Co-Authors: Evan W. Christen, John Hornbuckle, R ZandonnaAbstract:Subsurface Drainage is essential for sustainable agriculture. In many areas shallow water tables and soil salinisation require the use of engineered Subsurface Drainage to lower water tables and provide for leaching of the root zone. However, this Drainage water is often highly saline and disposal is problematic. Disposal to river systems has negative effects on downstream water quality and this option is becoming highly restricted in Australia. In some situations such as the Murrumbidgee Irrigation Area new Subsurface Drainage systems are required to dispose of Drainage water into evaporation basins to protect downstream users water quality. In order to meet disposal restrictions and the constraint of using evaporation basins a fully automated Subsurface Drainage system 'manager' has been developed. This manages Subsurface Drainage systems to minimise salt loads and pumping costs and meet disposal constraints. This example is for a fully automated system that will manage farm horizontal pipe Subsurface Drainage systems that incorporate the use of an evaporation basin for saline Drainage disposal.
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Best Management Practices for Minimizing Salt Loads from Subsurface Drainage Systems
2004Co-Authors: Ew Christen, J. E. Ayars, John HornbuckleAbstract:Subsurface Drainage water disposal is often a problem for agriculture in arid and semi-arid areas. This effluent often contains salt, toxic elements, pesticides, and fertilizers and thus represents a pollution source that contaminates the receiving water body. This presents challenges in Drainage disposal to avoid deleterious effects on downstream water quality. A review of Subsurface Drainage in Australia has shown that many systems drain excessive volumes of water, potentially reducing irrigation water use efficiency, and remove considerably more salt than applied in the irrigation water, indicating a mining of stored geologic salt. In the rainfed condition it will also be critical to minimize the mobilization of salt from the soil profile below the rootzone in order to reduce Drainage disposal problems. Best management practices (BMPs) have been developed for irrigated agriculture to address many environmental issues, however, prior to this time there were no BMPs developed for managing Subsurface Drainage to reduce salt loads in the Drainage waters. This paper presents BMPs that were developed for design and management of Subsurface Drainage systems used in arid and semi-arid irrigated areas. The authors believe that these best management practices can also be adapted to Subsurface Drainage under rainfed conditions. The principles outlined are broadly applicable to rainfed situations and can be taken as a starting point for Subsurface Drainage planning, design and management.
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A Methodology to Assess the Performance of Subsurface Drainage Salinity Control
2004Co-Authors: Ew Christen, John Hornbuckle, J. E. AyarsAbstract:The performance of Subsurface Drainage systems is rarely evaluated after installation either for physical or financial performance. Moreover, assessments are rarely made regarding the completion of salinity reclamation and hence the need to move to a reduced Drainage requirement. This paper provides a methodology based upon electromagnetic (EM) soil salinity survey to provide a temporal and spatial analysis of the effectiveness of Subsurface Drainage. This spatial assessment allows assessment of the effectiveness of the Drainage system, in terms of uniformity of reclamation and time to reclamation, and provides important data that can be used to implement differential management of the Subsurface drains. This may be to use controlled Drainage to reduce salt loads and hence reduce salt loads requiring disposal. Using the EM surveys and plant salinity tolerances, maps of potential relative yield are produced. This provides the basis for financial performance assessment of the Subsurface Drainage system.
Evan W. Christen - One of the best experts on this subject based on the ideXlab platform.
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Modeling Subsurface Drainage for salt load management in southeastern Australia
Irrigation and Drainage Systems, 2006Co-Authors: M. A. S. Wahba, Evan W. ChristenAbstract:Subsurface Drainage has been implemented in irrigation areas of South-eastern Australia to control water logging and land salinisation. Subsurface Drainage has been identified as a major salt exporter from irrigated areas. The water table management simulation model DRAINMOD-S was evaluated to simulate daily water table depth, drain outflow, and salt loads by using experimental field data from a two year field trial was carried out in the Murrumbidgee Irrigation Area South-eastern Australia to study different options for Subsurface Drainage system design and management to reduce salt load export. Three Subsurface Drainage systems were modeled, deep widely spaced pipe drains, shallow closely spaced drains and deep pipe drains that were managed with weirs to prevent flow when the water table fell below 1.2 m. The reliability of the model has been evaluated by comparing observed and simulated values. Good agreement was found between the observed and simulated values. The model confirmed the field observations that shallow drains had the lowest salt load and that by managing deep drains with weirs salt loads could be significantly reduced. This work shows the value of the DRAINMOD-S model in being able to describe various Drainage design and management strategies under the semi-arid conditions of South-eastern Australia. The model can now be used to investigate design and management options in detail for different site conditions. This will assist decision makers in providing appropriate Subsurface Drainage management policies to meet Drainage disposal constraints within integrated water resources management planning.
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Improving Subsurface Drainage design: minimising the environmental impacts
Australasian Journal of Water Resources, 2005Co-Authors: John Hornbuckle, Evan W. Christen, R. D. FaulknerAbstract:AbstractThis paper addresses how the design of Subsurface Drainage systems impacts on the Drainage volume and salinity of Drainage water generated. The effects of drain depth and spacing are reviewed and discussed. The conceptualisation of a Subsurface Drainage system which incorporates Drainage water quality into the design is presented. This system, known as a Multi-Level Drainage System, aims to minimise offsite impacts associated with Subsurface Drainage while still providing adequate protection from waterlogging and salinity of the plant root zone. This is achieved through the use of a shallow closely spaced Drainage system (0.7 m deep at 3.3 m) underlain by a deeper, widely spaced Drainage system (1.8 m deep at 20 m). Field investigations show that the shallow drains had approximately five times lower salinity than deep drains, with median values being 5.5 dS/m and 28 dS/m respectively. The results indicate that, by re-thinking Subsurface Drainage design to incorporate water quality aspects, alterna...
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Improving Subsurface Drainage Design - Minimising the Environmental Impacts
2004Co-Authors: John Hornbuckle, Evan W. Christen, R. D. FaulknerAbstract:This paper addresses how the design of Subsurface Drainage systems impact on the Drainage volume and salinity of Drainage water generated from these systems. The effects of drain depth and spacing are discussed along with the conceptualization of a Subsurface Drainage system which incorporates Drainage water quality into the design. This system, known as a Multi-Level Drainage System, aims to minimise offsite impacts associated with Subsurface Drainage while still providing adequate protection from waterlogging and salinity of the plant root zone. This is achieved through the use of a shallow intensely spaced Drainage system underlain by a deeper, widely spaced Drainage system. The results indicate that by re-thinking Subsurface Drainage design to incorporate water quality aspects alternative designs can be formulated which begin to meet the present day environmental constraints placed on Subsurface Drainage systems.
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Automated Subsurface Drainage Management System to Reduce Costs and Downstream Environmental Impact
2004Co-Authors: Evan W. Christen, John Hornbuckle, R ZandonnaAbstract:Subsurface Drainage is essential for sustainable agriculture. In many areas shallow water tables and soil salinisation require the use of engineered Subsurface Drainage to lower water tables and provide for leaching of the root zone. However, this Drainage water is often highly saline and disposal is problematic. Disposal to river systems has negative effects on downstream water quality and this option is becoming highly restricted in Australia. In some situations such as the Murrumbidgee Irrigation Area new Subsurface Drainage systems are required to dispose of Drainage water into evaporation basins to protect downstream users water quality. In order to meet disposal restrictions and the constraint of using evaporation basins a fully automated Subsurface Drainage system 'manager' has been developed. This manages Subsurface Drainage systems to minimise salt loads and pumping costs and meet disposal constraints. This example is for a fully automated system that will manage farm horizontal pipe Subsurface Drainage systems that incorporate the use of an evaporation basin for saline Drainage disposal.
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Subsurface Drainage design and management in irrigated areas of Australia
Irrigation Science, 2001Co-Authors: Evan W. Christen, James E. Ayars, John HornbuckleAbstract:Subsurface Drainage to protect irrigated cropping has been practised in some areas of Australia since the 1920s, and most irrigation districts have large land areas protected by some form of Subsurface Drainage. Across the irrigated areas, a broad spectrum of practices were developed that suited the conditions at the time of development. This paper assesses the performance of these Subsurface Drainage systems in terms of long-term sustainability of irrigated agriculture, based on the results of a detailed review of all the Subsurface Drainage systems in use in Australian irrigation areas. The long-term sustainability of irrigated agriculture depends upon controlling the salinity levels in the crop root zone and maintaining the ability to dispose of Drainage water. This requires that Subsurface Drainage systems are efficient in terms of removing the minimum amount of water with the lowest salinity possible, given the existing conditions, while still maintaining crop productivity. Analysis of the current Drainage system operation showed that many systems were draining greater volumes of water than designed for, leading to excessively high leaching fractions, and reduced irrigation water-use efficiency. The salt load removed by these systems was also often found to be far greater than the salt applied by irrigation, indicating a mining of stored salt. This is necessary from a salinised root zone but not if the salt is from below the root zone. The extra salt load above that required to maintain a salt balance in the root zone leads to increased difficulties in the disposal of the Drainage water due to downstream impacts. Suggestions are discussed for adaptive management and new design considerations that may help make Subsurface Drainage more efficient, leading to reduced negative downstream effects and reduced costs of disposal.
