Naim Haie

Hargreaves and Other Reduced-Set Methods for Calculating Evapotranspiration

Globally, irrigation is the main user of fresh water, and with the growing scarcity of this essential natural resource, it is becoming increasingly important to maximize efficiency of water usage. This implies proper management of irrigation and control of application depths in order to apply water effectively according to crop needs. Daily calculation of the Reference Potential Evapotranspiration (ETo) is an important tool in determining the water needs of different crops. The United Nations Food and Agriculture Organization (FAO) has adopted the Penman-Monteith method as a global standard for estimating ETo from four meteorological data (temperature, wind speed, radiation and relative humidity), with details presented in the Irrigation and Drainage Paper no. 56 (Allen et al., 1998), referred to hereafter as PM:

Macro, meso, and micro-efficiencies and terminologies in water resources management: a look at urban and agricultural differences

Efficiency of water resources is essential; just as important is the terminology that describes it. Paradoxes in terminologies used by various international institutions and professionals in the agricultural, urban and environmental domains are examined. Integrated terminologies are proposed, starting from flow-path types in water balance and expanded into the “macro, meso, and micro-efficiencies” (3ME) formulation. The 3ME is a systemic framework based on the principle of the conservation of mass, integrating water-flow paths of a water system, their beneficial and quality attributes (the usefulness criterion), climate, and two types of water totals. These terminologies, with nine examples for urban (three types) and agricultural areas (rainfed, surface, drip and sprinkler), are used to discuss the 3ME framework and possible flawed policy implications.

Sefficiency (sustainable efficiency) of water–energy–food entangled systems

Abstract Water–energy–food (WEF) entanglement is intensifying and technology is being presented as a crucial solution. But time and again the implemented alternative manifests results contrary to the objectives of design or management. To advance water security, transparent and complete input–output methodologies are needed. Here, a Sefficiency (sustainable efficiency) framework is used to reason through systemic analyses of options for WEF schemes by using water quantity within a comprehensive water balance, and quality and benefits in a multilevel water-use system. An energy regime (cost and normalized functions) and Sefficiency compute performance of four cases that show flaws both conceptually and practically in current policy and scientific tendencies.

Analysis of effective efficiency in decision making for irrigation interventions

Multiple stresses are putting great pressure on water resources systems. Population growth, climate change, prosperity, energy production, food crisis, and water governance are among the factors straining water resources. Decision makers from rich to poor countries and from commercial to non-governmental organisations are struggling to devise schemes to adapt to these stressed water conditions. Better efficiency for water resources systems, and particularly irrigation systems, is recommended as one of the most important responses to climate change, unsustainable development, and water shortage. However, using certain efficiencies such as Classical Efficiency caused systems not to perform according to decision makers’ objectives. Effective Efficiency is a robust composite indicator that includes in its formulation both a flow weight, taking into account the leaching fraction, and reuse of return flows. Classical Efficiency is defined as the percentage of the diversion consumed beneficially, such as by crop evapotranspiration. Effective Efficiency, on the other hand, is defined as the ratio of beneficial consumptive use to total consumption, expressed as a percentage. In this paper, a normalised and non-dimensional form of Effective Efficiency is developed and necessary constraints for its successful application are explained. These constraints express water balance, flow weights and their thresholds, water reuse, and total consumptive use. Basic guidelines are proposed for better decision making in determining possible interventions for improving Effective Efficiency. This is done by analysing its domain through analytical and graphical methods. Three real cases are considered, namely, Imperial Irrigation District and Grand Valley irrigation systems in the United States and Nile Valley in upper Egypt. Three-dimensional sensitivity analysis is performed on Effective Efficiency and its variables using the three cases. This leads to an examination of the validity of the analysis and to suggestions for better intervention options. Meanwhile, it is also shown why Classical Efficiency should be used with care.

Random walk forecast of urban water in Iran under uncertainty

There are two significant reasons for the uncertainties of water demand. On one hand, an evolving technological world is plagued with accelerated change in lifestyles and consumption patterns; and on the other hand, intensifying climate change. Therefore, with an uncertain future, what enables policy-makers to define the state of water resources, which are affected by withdrawals and demands? Through a case study based on thirteen years of observation data in the Zayandeh Rud River basin in Isfahan province located in Iran, this paper forecasts a wide range of urban water demand possibilities in order to create a portfolio of plans which could be utilized by different water managers. A comparison and contrast of two existing methods are discussed, demonstrating the Random Walk Methodology, which will be referred to as the “On-uncertainty path”, because it takes the uncertainties into account and can be recommended to managers. This OnUncertainty Path is composed of both dynamic forecasting method and system simulation. The outcomes show the advantage of such methods particularly for places that climate change will aggravate their water scarcity, such as Iran.

A stochastic‐dynamic modelling of mountain river watersheds of NE Portugal

Abstract An integrated methodology has been developed in order to create and validate a stochastic‐dynamic model of ecological integrity. It is based on a series of field datasets of the prevailing biological and environmental variables. The determination of the parameters to be included in the model resulted from a previous conventional multivariate statistical treatment of all collected information. STELLA 5.0® software has been used to develop the simulation models. In order to evaluate the ecological state of the studied ecosystems, multimetric indexes were used. They are ecologically relevant and sensitive to environmental stress agents. Composition, richness, abundance and trophic metrics of benthic macroinvertebrate communities were selected, hence enhancing the importance of pollution control and monitoring in aquatic ecosystems based on ecological integrity indicators. The samples of aquatic macroinvertebrate and the environmental and physico‐chemical data were collected from three sub‐basins of the rivers of Northeast Portugal. After applying the model to these watersheds, the obtained results are encouraging. A statistically confirmed validation was performed and they seem to demonstrate the models reliability. It also predicted reasonably well (statistically significant) the degradations noticed some 10 years later.

Decision Support Models In Water SupplySystems Planning

In this work, the theory of time series in the analysis of water consumption was applied. The study was developed using forecasting (short term) SARIMA models. Then was applied to characterise the consumption of the distribution network served by the reservoir of Urgeses in the city of Guimaraes. The characterisation is basically done through the study of the peak factor and the definition of the chronological diagrams of flow. To project (long term) the consumption, a computer program was developed and applied for the cascade models which decomposes the consumption into different components to be analysed. These are the annual trend, seasonality, autocorrelation and climatic correlation. INTRODUCTION In todays world one billion (1 000 000 000) people do not have access to clean water according to Serageldin [1]! Indeed usable water is (becoming) one of the major limiting factors in planning and development. In this respect, it is fundamental to adequately assess the basic elements of design in order to assure resource conservation. In particular in the existing water infrastructures which are (not) functioning efficiently, there is a great need to develop formal methodologies to reduce the risk of losses and promote proper planning for the future. Short term forecasting is again important in the management of the systems in order to reduce the costs in a number of areas like the operation of a pumping plant. FORECASTING OF CONSUMPTION SARIMA METHODOLOGY SARIMA model represents a Seasonal AutoRegressive Integrated Moving Average which is given by Box [2] as: B*)s, (1) Transactions on Ecology and the Environment vol 7,