Search results for " water management"
showing 10 items of 26 documents
Detecting Mild Water Stress in Olive with Multiple Plant-Based Continuous Sensors.
2021
A comprehensive characterization of water stress is needed for the development of automated irrigation protocols aiming to increase olive orchard environmental and economical sustainability. The main aim of this study is to determine whether a combination of continuous leaf turgor, fruit growth, and sap flow responses improves the detection of mild water stress in two olive cultivars characterized by different responses to water stress. The sensitivity of the tested indicators to mild stress depended on the main mechanisms that each cultivar uses to cope with water deficit. One cultivar showed pronounced day to day changes in leaf turgor and fruit relative growth rate in response to water w…
Economic effects of the consolidation of water utilities in Japan
2014
Water utilities are affected by economies of scale. However, in Japan most water utilities are small-scale water services. Therefore, they face enormous difficulties in terms of financial and personnel resources. To take advantage of economies of scale, the consolidation of water utilities has been promoted since 1965 by Japanese water authorities. The measure has been successful to some extent; nevertheless, consolidation has not progressed in recent years as was expected. This paper identifies the main barriers that hinder the consolidation of water utilities in Japan and describes the new promotion plan for the consolidation of water utilities developed by the Japan Water Works Associati…
Irrigation water intensity and climate variability: an agricultural crops analysis of Italian regions
2020
This paper examines the relationship between the requirement of water resources for irrigation and climate variability and analyses the ranking of the best and worst performance of irrigation water intensity for each Italian region. To measure water resources demanded by agriculture, the irrigation water intensity (IWI) indicator has been computed as the ratio between volumes of irrigation water and total crop harvested. By applying panel data methodologies to a regional dataset spanning from 2000 to 2009, we may address heterogeneity and omitted variable issues. By merging meteo-climatic with agricultural variables, we may confirm that water precipitations, maximum temperature, irrigation …
Tariffs and efficient performance by water suppliers: an empirical approach
2012
Water leaks are an environmental and sustainable issue as well as an economic issue. The objective of this paper is to analyse the efficiency of a sample of Spanish urban water systems by considering water leaks in a network as undesirable outputs. Data envelopment analysis (DEA), an analytical benchmarking methodology, is used to calculate technical and economic efficiency. We also discuss the possible relationship between efficiency and tariffs charged to users. Results show that the possibilities for reducing water leaks in networks are high, thus demonstrating that there is room for savings from an economic and environmental point of view. The assessment of efficiency performance could …
Measurements and Observations in the XXI century (MOXXI) : innovation and multi-disciplinarity to sense the hydrological cycle
2018
ISI Document Delivery No.: FV7JXTimes Cited: 4Cited Reference Count: 249Tauro, Flavia Selker, John van de Giesen, Nick Abrate, Tommaso Uijlenhoet, Remko Porfiri, Maurizio Manfreda, Salvatore Caylor, Kelly Moramarco, Tommaso Benveniste, Jerome Ciraolo, Giuseppe Estes, Lyndon Domeneghetti, Alessio Perks, Matthew T. Corbari, Chiara Rabiei, Ehsan Ravazzani, Giovanni Bogena, Heye Harfouche, Antoine Brocca, Luca Maltese, Antonino Wickert, Andy Tarpanelli, Angelica Good, Stephen Alcala, Jose Manuel Lopez Petroselli, Andrea Cudennec, Christophe Blume, Theresa Hut, Rolf Grimaldi, SalvatoreTaylor & francis ltdAbingdon; To promote the advancement of novel observation techniques that may lead to new so…
Ability of Preissmann slot scheme to simulate smooth pressurisation transient in sewers
2010
Urban drainage networks are generally designed to operate in a free-surface flow condition. However, as a consequence of heavy rainfall events or network malfunctioning, filling of sewers (pressurization) and network overflowing may occur. Several softwares are commonly used to simulate floods in drainage networks and their results are usually thought to be reliable and robust. However, no specific studies have been carried out on the behaviour of these softwares during the pressurization transient. Actually, mathematical models based on the momentum equation appear to be more suitable in correctly simulating the pressurization moving jump but models based on the energy equation are much mo…
From the Harbour to the City. The Process of Urban Renewal in Trapani
2016
The chapter describes the study case of Trapani historical watwerfront, in particular the design solution adopted for nautical sport events and linked to regional landscape quality. The Trapani fluidity is connetted with an entrenched sea cultural and natural heritage. Actions, plans and programmes implemented for regeneration and development are based on cultural and natural heritage to be regulated, connected and transformed, in order to preserve the urban and regional identity.
Public choice of urban water service management: a multi-criteria approach
2013
Local policy makers in developed countries have to make decisions in increasingly complex scenarios. Consequently, they should use all the tools available when deciding which management option is the most suitable for urban water service, given how important that service is and the variety of criteria involved in making such a decision. This article employs ‘analytic hierarchy process’ techniques to perform an ex post analysis of the decision to transfer the management of the urban water service in Granada (in southern Spain) to a public-private partnership. The main conclusion is that the decision was rational, in that it was the best possible alternative considering the hierarchy of prefe…
Sub-critical filtration conditions of commercial hollow-fibre membranes in a submerged anaerobic MBR (HF-SAnMBR) system: The effect of gas sparging i…
2012
A submerged anaerobic MBR demonstration plant with two commercial hollow-fibre ultrafiltration systems (PURON®, Koch Membrane Systems, PUR-PSH31) was operated using municipal wastewater at high levels of mixed liquor total solids (MLTS) (above 22gL -1). A modified flux-step method was applied to assess the critical flux (J C) at different gas sparging intensities. The results showed a linear dependency between J C and the specific gas demand per unit of membrane area (SGD m). J C ranged from 12 to 19LMH at SGD m values of between 0.17 and 0.5Nm 3h -1m -2, which are quite low in comparison to aerobic MBR. Long-term trials showed that the membranes operated steadily at fluxes close to the est…
Experimental study of the anaerobic urban wastewater treatment in a submerged hollow-fibre membrane bioreactor at pilot scale
2011
The aim of this study was to assess the effect of several operational variables on both biological and separation process performance in a submerged anaerobic membrane bioreactor pilot plant that treats urban wastewater. The pilot plant is equipped with two industrial hollow-fibre ultrafiltration membrane modules (PURON¿ Koch Membrane Systems, 30m 2 of filtration surface each). It was operated under mesophilic conditions (at 33°C), 70days of SRT, and variable HRT ranging from 20 to 6h. The effects of the influent COD/SO 4-S ratio (ranging from 2 to 12) and the MLTS concentration (ranging from 6 to 22gL -1) were also analysed. The main performance results were about 87% of COD removal, efflu…