Stability of the WTP measurements with successive use of choice experiments method and multiple programmes method

This paper is part of an investigation to evaluate the benefits of landscape policies. Such policies are, within a specific area (here the Monts d’Arrée in Brittany), favouring some landscape attributes. We test out a procedure based on a double device. The first one relies on the choice experiments method and focuses on each attribute. Without prior information about the presence of substitution and complementarity effects between attributes, we work on the basis of scenarios built to ensure the independence of attributes. The important question of the impact of an attribute variation on the aesthetic value of another one, when these attributes are jointly perceived, is tackled by use of the multi-programme method. The two surveys were launched after an interval of one year, sampling among the same population. The WTP results obtained from each method are not statistically different.Valuation; choice modelling; multi-attributes choice set; multi-programme method; choice experiments; landscape; Monts d’Arrée

Intergenerational justice and environmental issues. What about discounting? (In French)

The aim of this paper is to explore the connections between the time dimension of economic phenomena and that of natural ones within the context of global (joint emissions of the energy sector) or local (joint product of waste) pollutions affecting present and future generations. Discounting constitutes a first way but leads to some difficulties when fairness must be taken into account. Furthermore, to take into account the interdependencies between economics and natural environment involves irreversibility of time. At last, ethics which is a key dimension of the sustainable development is introduced with Jonas’s responsibility principle. In this way, discounting can be used under some limits regarding economic decisions.intergenerational equity; discounting; responsibility principle; irreversibility; sustainable development

Hydraulic Modeling of a Mixed Water Level Control Hydromechanical Gate

This article describes the hydraulic behavior of a mixed water level control hydromechanical gate present in several irrigation canals. The automatic gate is termed "mixed" because it can hold either the upstream water level or the downstream water level constant according to the flow conditions. Such a complex behavior is obtained through a series of side tanks linked by orifices and weirs. No energy supply is needed in this regulation process. The mixed flow gate is analyzed and a mathematical model for its function is proposed, assuming the system is at equilibrium. The goal of the modeling was to better understand the mixed gate function and to help adjust their characteristics in the field or in a design process. The proposed model is analyzed and evaluated using real data collected on a canal in the south of France. The results show the ability of the model to reproduce the function of this complex hydromechanical system. The mathematical model is also implemented in software dedicated to hydraulic modeling of irrigation canals, which can be used to design and evaluate management strategies

An integrated approach: Assessing the potential impact of policy and management changes on irrigation system performance

Irrigation ManagementIrrigation programsPerformance evaluationPolicy

Water markets in Pakistan: Technical feasibility and potential impact on irrigation system performance

Water marketPerformanceIrrigation waterSurface waterWater allocationPolicyResearch methods

Integis: A tool for an integrated analysis of irrigation system management

Irrigation management / Irrigation programs / Irrigation canals / Operations / Computer models / Computer software / Pakistan / Chishtian Sub-division

Salinity and sodicity management in Pakistan

Irrigation management / Salinity control / Sodic soils / Policy / Research methods / Pakistan

Real Estate and Land Values on the shoreline: a transaction-level analysis (In French)

Land use changes generate some conflicts, in particular between agricultural and residential uses in the urbanization context and sprawl phenomena. Coastal zones also produce specific amenities that create conflicts over land-use, increase housing and land values and, associated with and/or substituted to urban amenities modify the structure of the territory.\r\nThis article is aimed at studying the influence of coastal and urban amenities, respectively defined in terms of accessibility to the sea side and to employment center, on prices. We differentiate the analysis between two distinct study areas according to the degree of urban development: the Charente coast that is still highly agricultural, and the Basque coastal area more urbanized. According to these local specificities, we will study with the same hedonic pricing method land use prices in the first case and property prices in the second.\r\nThe main results underline the major influence of littoralisation as structural phenomena in housing and land prices dynamics. We identify two different types of gradient of values in relation to distance to sea side as regards to the residential or agricultural use: a “growth premium” explains the agricultural land price gradient whereas both amenity and accessibility premiums justify the residential gradients.coastal areas, land and housing markets, hedonic pricing, gradients