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Ecosystem Services (ES) are the benefits that people obtain from ecosystems. They result from structures, processes and functions within ecosystems performed by natural features and organisms, and which society makes direct use of, consciously or unconsciously. The ES concept results in a general broadening of perspectives considering environmental effects of human activities, as well as their costs and benefits, in an integrated manner. This paper addresses the use and relevance of the Ecosystems Services concept for the Waterborne Transport Infrastructure (WTI) sector. Considering the potential multi-functionality of WTI, welldesigned projects can create economic, social and environmental benefits well beyond their intended waterborne transport objectives. When planning a project, the consideration of how project engineering aspects interact with biodiversity, fisheries, recreation and other sectors allows planners and other stakeholders to make well informed decisions about trade-offs and opportunities. The ES concept helps to make these trade-offs visible and integrate these considerations into different stages of the project cycle. Building on a range of case studies, we provide practical guidance on how ES concepts can be successfully applied at different stages of a WTI project, signposting further guidance on how the navigation sector can supportively, beneficially, and profitably use ES concepts to enhance and promote WTI projects.

Extrait de document; Prioritising sediment sites for management at the catchment scale involves the balancing of several kinds of risk and management objectives. At this spatial scale, management objectives are globally threefold: (i) meeting regulatory criteria, or political goals, (ii) maintaining (or restoring) economical viability, and (iii) ensuring environmental quality. Although the corresponding drivers differ for these three categories of objectives, risk indicators at this spatial scale tend to overlap, or to display logical connections. For this reason, and because these management objectives are indeed not independent when setting management actions, a general prioritisation approach can be proposed at the catchment scale, using a pre-defined set of criteria. The relevant criteria for setting priorities at catchment scale must account for the location of a sediment site within the catchment, its potential energy, its quality, both in absolute terms and relative to surrounding sites, and the benefits (and risks) of potential management actions. The criterion energy cannot simply be represented by the slope or the relative elevation within the catchment, because some infrastructure, such as dams, will lower the risk of transport downstream. Thus, basin-scale prioritisation will require the development of criteria that take into account gradients with a term of directionality, as well as erosive potential. Nevertheless, the latter criterion expected benefit could be viewed as result of the combination of other criteria, in particular location and sediment quality. As an initial test of these concepts, our working group has selected two classification approaches, namely score ordination and fuzzy logic; a test of both approaches on a common dataset will be presented and discussed in light of the selection of relevant parameters. It will as well provide an overview of the strengths and limitations of the two selected approaches according to robustness, methodology (related to the ease of use), sensitivity, appropriateness (referring to the range of conditions), and transparency.

Prioritising sediment sites for management at the catchment scale involves the balancing of several kinds of risk and management objectives. At this spatial scale, management objectives are globally threefold: (i) meeting regulatory criteria, or political goals, (ii) maintaining (or restoring) economical viability, and (iii) ensuring environmental quality. Although the corresponding drivers differ for these three categories of objectives, risk indicators at this spatial scale tend to overlap, or to display logical connections. For this reason, and because these management objectives are indeed not independent when setting management actions, a general prioritisation approach can be proposed at the catchment scale, using a pre-defined set of criteria. The relevant criteria for setting priorities at catchment scale must account for the location of a sediment site within the catchment, its potential energy, its quality, both in absolute terms and relative to surrounding sites, and the benefits (and risks) of potential management actions. The criterion energy cannot simply be represented by the slope or the relative elevation within the catchment, because some infrastructure, such as dams, will lower the risk of transport downstream. Thus, basin-scale prioritisation will require the development of criteria that take into account gradients with a term of directionality, as well as erosive potential. Nevertheless, the latter criterion expected benefit could be viewed as result of the combination of other criteria, in particular location and sediment quality. As an initial test of these concepts, our working group has selected two classification approaches, namely score ordination and fuzzy logic; a test of both approaches on a common dataset will be presented and discussed in light of the selection of relevant parameters. It will as well provide an overview of the strengths and limitations of the two selected approaches according to robustness, methodology (related to the ease of use), sensitivity, appropriateness (referring to the range of conditions), and transparency.

Acceptance and implementation of a basin-scale approach will require significant work, both technical and political. However, successful development of a basin-scale risk management framework should provide the basis for parties with very different goals for sediment to come together in support of sustainable sediment management. We recommend that effective and sustainable management strategies focus on the entire sediment cycle, including suspension-sedimentation processes along the whole river basin. A Conceptual Basin Model (CBM), describing the dynamic processes (soil-sediment-water-contaminant) within the catchment, should be set up and the basin-scale management objectives (BMOs) should be identified in order to develop a Basin Management Plan. This Basin Management Plan should define/list the goals for both the river basin and individual sites. A comprehensive Basin Scale/Site specific risk management approach is recommended that includes the following steps: 1) The communication between managers and the public, throughout the decision process, 2) The identification of management objectives, 3) The determination of appropriate risk indicators, 4) the usage of risk indicators to prioritise sites on a river basin scale and to rank risks on site-specific scale, 5) the decision making process in which potential effects on the river basin and on the site-specific scale are weighed against each other, taking into account the economic, societal and environmental risk, and finally 6) the selection, implementation and monitoring of the final management option(s). A prerequisite for sediment management on river basin scale is the harmonization of site prioritisation (basin scale) and site-specific assessment (risk ranking) schemes A DPSIR ('Driver-Pressure-State-Impact-Response') approach, along with the use of CBMs to quantify and communicate basin dynamics, should be used to facilitate communication between stakeholders (including the public). We applied these to describe the relationships between social and societal forces, the objectives of risk management and the potential management options, and the prevailing interests. © 2004 ecomed publishers (Verlagsgruppe Hüthig Jehle Rehm GmbH).