Copyright (c) 2008 All rights reserved. http://works.bepress.com/amgad_elmahdi Recent documents in Amgad ELMAHDI en-us Sat, 02 Aug 2008 03:32:27 PDT 3600 http://works.bepress.com/amgad_elmahdi/27 http://works.bepress.com/amgad_elmahdi/27 Thu, 31 Jul 2008 20:31:28 PDT Amgad ELMAHDI Water Banking http://works.bepress.com/amgad_elmahdi/26 http://works.bepress.com/amgad_elmahdi/26 Thu, 31 Jul 2008 20:21:46 PDT The combination of global warming, low rainfall, reduced recharge/run off and increasing water extraction/demand has resulted in (falling groundwater levels ) a situation that is no longer ecologically or socio-economically sustainable fresh water system. Simply in Gnangara mound groundwater system, more water is leaving the system to meet consumptive demand than is coming into the system through rainfall/recharge. This situation resulted in decline water table/level significantly in some parts of the mound. This impact observed as dieing vegetation, drying wetlands and caves and reduced sustainability of the system into future. Water authorities are now facing a great challenge to meet requirements with new urbanization plan, reallocating horticultural area, increasing population and increasing demand. This paper provides a better understanding of how the groundwater system on Gnangara mound responds to the change in the climate and landuse with evaluation of its socio-economic impacts and tradeoffs. In order to evaluate this system, an object-oriented system dynamics approach has been used to develop an integrated model. Preliminary results from the development and application of the model for quantifying sustainability of Gnangara mound system is presented with emphasis on the understanding of the tradeoffs of changing climatic conditions and landuse planning. Water levels vary significantly under different climatic conditions (recharge regimes). Changing and reallocating landuse is able to improve recharge in some parts of the system but this cannot reverse the overall trend of falling levels as the climate signal is pervasive. Amgad ELMAHDI Groundwater Modelling http://works.bepress.com/amgad_elmahdi/25 http://works.bepress.com/amgad_elmahdi/25 Thu, 31 Jul 2008 20:05:32 PDT Global warming and drought conditions lead to reduced water availability. Competing and conflicting water uses and other water-related environmental problems are rapidly increasing in many parts of the world, including Australia. Moreover, water demand for irrigation is driven by cropping activities which, result in higher river flows during summer and altered flow regimes that in turn alter the seasonality of flows considering climatic uncertainty. This can have important ecological and economic impacts. Therefore, there is a need to explore new management system to integrate all the available information and values (economic, environmental and social) considering uncertainty involved to better understand the trade-off between environmental performance and water productivity.Using a combined system-dynamics and optimisation approach, plus spatial and modelling data, an integrated hydrological economic environmental model (DSS) can be developed to assist the land and water managers to make decisions based on the evaluation of the trade-off between Agricultural productivity and environmental performances with the triple bottom line (environmental, social and economic). Amgad ELMAHDI System Modelling http://works.bepress.com/amgad_elmahdi/24 http://works.bepress.com/amgad_elmahdi/24 Thu, 31 Jul 2008 19:41:58 PDT Global warming has impacted the four dimensions of the food security problem, namely: availability (including production and trade); stability of supply (dependent on available water); accessibility; and utility. The food-water security system is diverse in size, in character, and in time. Moreover, the food-water security system management is complex due to the uncontrolled nature of the climate change variables, and because the assessment of the efficacy of management decisions is difficult due to the complexity and interconnectivity of water systems components (environment, physical, agricultural and socio-economic). Further complexity is added where natural resource management (NRM) is decentralised and a catchment or region is covered by several management bodies. Essentially most of the quantitative assessments in the previous studies show that climate change has adversely affected food security. Climate change will increase the dependency of developing countries on imports and accentuate existing focus of food insecurity on many countries around the world. Also, previous assessments show that the socio-economic environment is more important than the impacts that can be predicted from the biophysical changes of climate change. Accordingly, this study aims at introducing an integrated system model for food and water security management system for Egypt case study. The framework is designed in more flexible fashion using a simple graphical user interface through VENSIM platform to allow the decision makers to have the ability of selecting several policy making variables and change them over the assigned planning time horizon. The model is able to simulate different scenarios and alternatives for different time horizon. The developed integrated framework shows robustness in dealing with such complicated issues and allows the decision maker to have a reliable vision for the future situation regarding water and food security. Amgad ELMAHDI Integrated Water Resources Food and Water Security Strategy http://works.bepress.com/amgad_elmahdi/23 http://works.bepress.com/amgad_elmahdi/23 Mon, 28 Jul 2008 19:17:02 PDT Amgad ELMAHDI Irrigation system http://works.bepress.com/amgad_elmahdi/22 http://works.bepress.com/amgad_elmahdi/22 Mon, 28 Jul 2008 19:14:02 PDT Amgad ELMAHDI Irrigation system http://works.bepress.com/amgad_elmahdi/21 http://works.bepress.com/amgad_elmahdi/21 Mon, 28 Jul 2008 19:07:27 PDT This paper presents the use of water banking concept (using aquifers as a natural underground dam) combined with different changing landuse such as crop mixes to improve river water productivity and environmental performance. The goal of water banking, in general, is to efficiently allocate all available water to achieve an economic growth while achieving an environmental sustainability. As a case study, Water banking, along with two methods of managed aquifer recharge, have been modeled and tested under different crop mixes by using a dynamic modeling system approach for Murrumbidgee River Basin in Australia,. The results indicated that there is a clear trade-off between improving water use efficiency, agricultural productivity and environmental performance. Water banking is able to better manage biophysical demand, and enhance in-stream flows that are biologically and ecologically significant. Amgad ELMAHDI Water Banking http://works.bepress.com/amgad_elmahdi/20 http://works.bepress.com/amgad_elmahdi/20 Mon, 28 Jul 2008 19:04:11 PDT Amgad ELMAHDI System Modelling http://works.bepress.com/amgad_elmahdi/19 http://works.bepress.com/amgad_elmahdi/19 Mon, 28 Jul 2008 19:01:12 PDT Amgad ELMAHDI Water System Sustainability Indicator http://works.bepress.com/amgad_elmahdi/18 http://works.bepress.com/amgad_elmahdi/18 Mon, 28 Jul 2008 18:56:32 PDT The Warrion region in south west Victoria, Australia, has been subjected to land cover changes, groundwater pumpage and irrigation. Declining groundwater levels over the past decade has focused attention on the impacts of irrigation practices and research to date has identified groundwater extraction as the primary cause of falling groundwater levels and the drying of a significant group of lakes. However, recent declines in groundwater levels have coincided with reduced rainfall, and it has been hypothesised that severe drought over the past ten years has affected groundwater levels in the Warrion more significantly than has been thought. To test this hypothesis a simple one-dimensional model was developed to determine how well groundwater behaviour could be estimated from rainfall and evapotranspiration. The region is understood to be a local groundwater system with recharge occurring along the elevated ridge of the central range and groundwater discharge into the lakes on either side. The system was conceptualised as three connected reservoirs, with an upper, recharge, reservoir (the groundwater store) draining to two lower, discharge, reservoirs (the lakes). Input to the upper reservoir is a function of rainfall and evaporation, while outflow to the lakes is a function of the height difference between the upper and lower reservoirs and hydraulic conductivity -- in accord with Darcy's Law. A system dynamics approach has been taken to modelling the system using the object oriented programming language, VENSIMTM. The model was calibrated to recorded monthly groundwater level measurements. The best fit was obtained where the model was calibrated using the last half of the record (R2 = 0.95) and validated using the first half. An R2 of 0.925 was obtained for the full historic record (total 83 monthly values). No lag was required for the rainfall record. Results show groundwater fluctuations can be simply modelled using rainfall and lake levels data. Recharge is estimated at around 30%. This has led to the conclusion that groundwater trends are strongly linked to reduced rainfall. Amgad ELMAHDI Groundwater Modelling http://works.bepress.com/amgad_elmahdi/17 http://works.bepress.com/amgad_elmahdi/17 Mon, 28 Jul 2008 18:53:34 PDT Amgad ELMAHDI Water Banking http://works.bepress.com/amgad_elmahdi/16 http://works.bepress.com/amgad_elmahdi/16 Mon, 28 Jul 2008 18:48:00 PDT Amgad ELMAHDI Integrated Water Resources http://works.bepress.com/amgad_elmahdi/15 http://works.bepress.com/amgad_elmahdi/15 Mon, 28 Jul 2008 18:43:56 PDT Amgad ELMAHDI Integrated Water Resources http://works.bepress.com/amgad_elmahdi/14 http://works.bepress.com/amgad_elmahdi/14 Mon, 28 Jul 2008 18:41:50 PDT Amgad ELMAHDI River Salinity http://works.bepress.com/amgad_elmahdi/13 http://works.bepress.com/amgad_elmahdi/13 Mon, 28 Jul 2008 18:37:26 PDT Water demand is driven by cropping activities which result in higher river flows in the reaches upstream of the irrigation areas. This situation led to alter flow regime in turn alters the seasonality of flows which significantly causing important ecological impacts. The combination of regulation, operation and water polices has also resulted in a significant reduction in flow variability. Maintaining irrigation supply flows and increasing river flows for environmental requirements downstream represent a critical challenge and requires innovative solution. One promising option to achieve these two objectives is the conjunctive use management of surface and groundwater using water banking. The aim of this study is to present and investigate the use of water banking concept to the farmers and water mangers as it is critical and important as its design and operation to improve the environmental performance of the river. Water banking has been modeled and introduced to the integrated hydrological, economic and environmental river modelling framework (NSM) for the Murrumbidgee River catchment using system dynamics approach. The model has been tested water banking under different management scenarios under different climatic conditions and two recharging methods (infiltration and injection). Results indicate two strong messages; Firstly there is clear trade-off between agricultural income, environmental performances and water use; Secondly; water banking performed as a good mechanism that is can managing irrigation demand, and in turn improve the seasonal flows and enhance in-stream flows that are biologically and ecologically significant. Amgad ELMAHDI Water Banking http://works.bepress.com/amgad_elmahdi/12 http://works.bepress.com/amgad_elmahdi/12 Mon, 28 Jul 2008 18:32:54 PDT Amgad ELMAHDI Water and Biomimicry http://works.bepress.com/amgad_elmahdi/11 http://works.bepress.com/amgad_elmahdi/11 Mon, 28 Jul 2008 18:29:42 PDT The aim of this study is to present humanity and termites as design partners in the creation of a new dimension of human understanding. This understanding is based upon the likelihood that termites have developed optimal architecture and design for water and soil conservation in ecosystems over millions of years. In this biomimicry study the objective is to apply and perfect termite system designs for better water and soil management by government, industry and the public. Termites create structures that regulate and maintain near-constant moisture and temperature. Termites also create self-regulating energy systems that need no mechanical power for cooling and/or heating. In tropical climates, termites improve soil structure and moisture holding capacity and conserve water according to changing environmental conditions. Can our water and soil management systems mimic termite management styles? This study also focuses on using termites' techniques to improve soil physical characteristics. Termites play an important role in rehabilitating degraded ecosystems and widening soil microbial diversity. Accessing water sources from underground and the burrowing and feeding activities of termites can slow and reverse land degradation. In addition, termites have the potential to improve the structure of crusted soils, including their capacity to limit soil compaction, increase soil porosity and improve the water infiltration and retention capacities of soils. Such conditions encourage root penetration, vegetative diversity, and restores primary productivity; all preconditions for food and prosperity security in Australia. The role of termites in organic matter decomposition and water conservation is well recognized. However, few studies have examined the behavioral and ecological approach of termites in relation to water and soil conservation. Sustainable water and soil management is a key to every society's survival and development. Degraded soil structure and surface sealing of soils impede water infiltration and plant root growth, limiting the usefulness of local lands for crop and animal production. Amgad ELMAHDI Climate and Environment Water and Biomimicry http://works.bepress.com/amgad_elmahdi/10 http://works.bepress.com/amgad_elmahdi/10 Mon, 28 Jul 2008 18:24:38 PDT ABSTRACT Global warming issue and increasing vulnerability of biodiversity are the main issues facing the world and particularly Australia. Australia has a rich fauna of termites mainly in mainland areas. Termites are primarily tropical and subtropical insects, and play an important role as an 'ecosystem engineers' because of their ability to decompose wood material. They have major effects as nutrients recyclers, and in influencing energy flow. In recent times there are few study attempted to identify and establish the link between termites' distribution (phylogeographgy), invasions and climate; and how this distribution might change with global warming and changes in drought frequency. Australia is facing sever drying conditions and reduced rainfall and precipitation which in turn reduced soil moisture and changed soil physical characteristics. Hence, this study attempts to study the link between termites phylogenography and climatic conditions by applying molecular DNA bar-coding analysis for termites species from different climatic zones and states to develop a multidisciplinary integrated distributional model for Australian termite fauna and biodiversity in consideration of several factors such as vegetation type, ecosystem nature, temperature average, average rainfall, evaporation rate and soil type. Preliminary results show there is a clear tradeoff between climate conditions and termite's distribution and biodiversity, the most sensitive parameters are rainfall, soil moisture, precipitation and temperature. Amgad ELMAHDI GIS and Quality of Life Climate and Environment http://works.bepress.com/amgad_elmahdi/9 http://works.bepress.com/amgad_elmahdi/9 Mon, 28 Jul 2008 18:17:34 PDT Abstract Improving the efficiency of water allocation has long been recognised as a key problem for the water resources management decision-makers. However, assessing the efficacy of management decision is difficult due to the complexity and interconnectivity of water resource systems. For this reason, it is vital that robust modelling approaches are employed to deal with the feedback loops inherent in the water resource systems. Whilst many studies have applied modelling to various aspects of water resource management, little attention has been given to innovations in modelling approaches to deal with themodelling challenges associated with improving decision-making. The aim of this study is to apply a System Dynamics modelling approach to improve the efficiency of water allocation incorporating a myriad of irrigation system constraints. The system dynamic approach allows the different system components to be organised as a collection of discrete objects that incorporate data, structure and function to generate complex system behaviour. Through the application of a system dynamic approach, a robust model (named the Economical ReallocatingWater Model (ERWM)) was developed which was used to examine the options of re-allocating water resources that minimize the water cost all over an irrigated agricultural area. The ERWM incorporated a wide range of complexities likely to be encountered in water resource management: surface and ground water sources, water trading between sources, system constraint such as maximum ground water pumping, rates, maximum possible trading volumes and differential water resource prices. Two hypothetical systems have been presented here as an example. The results show that the System Dynamics approach has a significant advantages in estimating and assessing the outcomes of alternative water management strategies through time and space. Amgad ELMAHDI System Modelling http://works.bepress.com/amgad_elmahdi/8 http://works.bepress.com/amgad_elmahdi/8 Mon, 28 Jul 2008 18:14:06 PDT Amgad ELMAHDI GIS and Quality of Life http://works.bepress.com/amgad_elmahdi/7 http://works.bepress.com/amgad_elmahdi/7 Mon, 28 Jul 2008 18:10:53 PDT Water sharing management is the major problem for water resources and irrigation management decision makers. However, irrigation systems are very complex and interconnected, posing significant difficulties in managing irrigation economically and environmentally. Therefore, it is imperative that innovative modelling approaches are employed to deal with the feedback loops inherent in these systems. Through the application of a system dynamics approach, a Network Simulation Model (NSM) was developed. The purpose of the NSM is to measure and identify the change in economic and environmental outputs of various allocations and demand scenarios. The aim of this study is to examine the use of two methods of auto calibration (single objective and multiobjective) over a variety of climatic and hydrological conditions. These methods have been compared and applied to three periods of calibration and validation using seven performance criteria. Results indicate that multiobjective method yields better identifiable parameters and an improved model structure Amgad ELMAHDI System Modelling http://works.bepress.com/amgad_elmahdi/6 http://works.bepress.com/amgad_elmahdi/6 Mon, 28 Jul 2008 18:06:00 PDT Irrigation, over extraction and land clearing has had major impacts on river environment particularly in the Murrumbidgee river catchment. Increased water demands for agriculture and other uses have led to low flows and changes in the seasonal flow patterns. However, as further growth in water diversions is not possible due to the imposition of the Murray Darling Basin Cap, the need to achieve improved environmental and economic outcomes in allocation policies requires greater efficiency in the use the limited water resources. This paper presents a system dynamics approach to modelling aimed at assisting stakeholders in understanding, predicting and resolving potential water sharing conflicts which have becomes more acute after the imposition of Cap on diversions and new environmental flow rules. A dynamic agricultural network simulation model based on an economic concept was developed to analyse the historical water allocation in the Coleambally irrigation area within the constraints of existing environmental flow rules. This is the first attempt to apply a system dynamics approach for irrigation demand management at the irrigation area level. This network model uses a node-link approach to represent the Coleambally irrigation system. The model is tested using various hypothetical scenarios, such as change the crop areas, environmental flow targets, and water pumping. Furthermore, the model is shown to be a useful policy and planning tool for water supply authorities, policy and decisions makers and irrigators. Amgad ELMAHDI Groundwater Modelling System Modelling http://works.bepress.com/amgad_elmahdi/5 http://works.bepress.com/amgad_elmahdi/5 Mon, 28 Jul 2008 18:00:50 PDT Abstract: Integrated water resources planning and management are considered a very complex issue. It is usually solved through the multi-sectoral, interdisciplinary and hierarchal decomposition approaches. In general, integrated resource management indicates the consideration of water, social, socio-economic, economic and environmental issues. The current study aims at merging the GIS and Multi-Criteria evaluation (MCE) techniques for integrated water resource management of a cropped area. Thus, an area of about 120000 Hectares located at Northern Nile River Delta area with a coastal zone on the Mediterranean was selected. GIS was applied to represent the area with its different environment, social, economic, and water factors. Different randomization cropping pattern distribution scenarios were proposed. Through the merging of GIS and MCE approaches, three scenarios were run and evaluated at three different levels that are farm, canal catchment area and whole area. This merging results in a very powerful tool for evaluation of different plans. The merging of GIS and MCE is really facilitated the decision making process for such type of integrated water management Problems. Amgad ELMAHDI Integrated Water Resources http://works.bepress.com/amgad_elmahdi/4 http://works.bepress.com/amgad_elmahdi/4 Mon, 28 Jul 2008 17:56:24 PDT EXTENDED ABSTRACT Groundwater is a vital resource in Australian agriculture. Increased demand for water resulting from rapid economic development accompanied by poor climatic conditions (e.g. low rainfall levels) has induced an increased reliance on groundwater harvesting to sustain intensive irrigation practices. Overdraft of groundwater as a result of reduced surface water availability, increased economic viability of farms and the capping of river catchment allocations have considerably lowered water tables. This paper describes a decision support system to aid in the sustainable water resource use in the Werribee Irrigation District (WID) in Victoria. This particular district provides an ideal set up for the investigative work described below as it has a fully calibrated groundwater model and more importantly, it is at risk of salinization due to sea water intrusion. A decision support system linking crop water requirements with the available water for irrigation (surface and groundwater) is developed using a systems dynamic approach (system dynamics offers a new way of modelling the future dynamics of complex systems) by dynamically linking crop distribution patterns with the behaviour of a coastal aquifer using a finite difference three dimensional modelling approach. This allows the optimisation of agricultural production while respecting sustainable groundwater levels in the aquifer. The Modflow 2000 code is used to simulate groundwater dynamics in the Werribee Irrigation District. VENSIM-DSS software, a system dynamics tool, was used to optimise crop distribution in the Werribee Irrigation District (WID) in Victoria. This was done by linking Crop distribution mix and water demand under set constraints to groundwater drawdown spatial distribution resulting from Modflow simulations scenarios. The study time frame was set to 12 months. Four case scenarios were tested: a high water use scenario, a medium water use scenario, a no rice water use scenario and a low water use scenario (Vegetables Only). It was found that the "Vegetable Only" scenario was the most sustainable as pumping didn't breach the predefined sustainability limit1. Economic Surface and Groundwater Model (ESGM) was linked to a calibrated numerical Model developed under Modflow (USGS, 1984). The dynamic link takes care of the constraint checking and makes it easier for non-modellers to test various scenarios. This management tool as proposed presents the advantage of linking system dynamics to physical processes hence giving more realistic outcomes Amgad ELMAHDI Groundwater Modelling http://works.bepress.com/amgad_elmahdi/3 http://works.bepress.com/amgad_elmahdi/3 Mon, 28 Jul 2008 17:48:49 PDT Abstract Integrated Water Resources planning and Management is considered a very complex issue. It is usually solved through the multi-sectoral, Interdisciplinary and hierarchal decomposition approaches. In general, integrated management indicates the consideration of water, social, socio-economic, economic and environmental issues. The current study aims at merging the GIS and Multi-Criteria evaluation (MCE) approaches and solves the integrated management of a cultivation area. Thus, an area of about 120.000 thousand acres (250.000 Feddan) has been selected to be simulated through the merging of GIS and MCE for the scale of integrated management. The selected area is located at Northern Nile River Delta area with a coastal zone on the Mediterranean. The GIS has been applied to picture the area with its different sectors that are: social, economic, environment and water. Different randomization cropping pattern distribution scenarios have been proposed. Through the merging of GIS and MCE three scenarios have been run and evaluated on three different levels: farmer, canal catchments area and integrated area. It has been found that this merging is result in a very powerful and robust tool for evaluation of different proposed plans on the integrated levels. The merging of GIS and MCE is really facilitated the decision making process for such type of problems. It is recommended to use such methodology in the integrated management of similar problems. Amgad ELMAHDI Integrated Water Resources http://works.bepress.com/amgad_elmahdi/2 http://works.bepress.com/amgad_elmahdi/2 Mon, 28 Jul 2008 17:36:36 PDT Abstract An indicator defined as a function of the total water diversion through the Coleambally canal and the potential irrigation demand is selected to represent the sustainability of the irrigation water system in the Coleambally irrigation area, Australia. A simulation procedure was developed to evaluate the indicator. The procedure includes water diversion assessment, potential crop water demand and total gross margin. Three cases of water supply options (ground water pumping and water trading), two cases of changes in the total agricultural area and three cropping pattern scenarios were simulated to better understand their impact on sustainability. The simulated results indicate that increasing the agricultural area will reduce the sustainability of the irrigation system as the demand will be more than 80 percent despite increase the gross margin. The scenarios shown that imposed water trading and ground water pumping would considerably increase the supply system having a positive impact on the sustainability. The paper concludes that a multi-objective sustainability indicator taking account of economic and environmental issues could be more useful. Amgad ELMAHDI Water System Sustainability Indicator http://works.bepress.com/amgad_elmahdi/1 http://works.bepress.com/amgad_elmahdi/1 Mon, 28 Jul 2008 17:20:46 PDT Abstract: The objective of this paper is to develop and present a GIS-based and software tool capable of data management, data visualisation, and data analysis. The developed software is proved to be a good tool in the initial assessment of the quality status of the Nile river water quality. In addition a Graphical User Interface (GUI) was fully designed and implemented to make the GIS tool very easy and handy for the decision maker. Spatial analysis and visualisation of water quality data can be easily presented through the interface. It is concluded that water quality along the main stem is much better than the quality along the two main branches, where more violations are observed. Amgad ELMAHDI GIS and water quality