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Resource refers to all the materials available in our environment which are technologically accessible, economically feasible and culturally sustainable and help us to satisfy our needs and wants. Resources can broadly be classified upon their availability — they are classified into renewable and non-renewable resources. They can also be classified as actual and potential on the basis of the level of development and use, on the basis of origin they can be classified as biotic and abiotic, and on the basis of their distribution, as ubiquitous and localised (private, community-owned, national and international resources). An item becomes a resource with time and developing technology. The benefits of resource utilization may include increased wealth, proper functioning of a system, or enhanced well-being. From a human perspective, a natural resource is anything obtained from the environment to satisfy human needs and wants. From a broader biological or ecological perspective, a resource

Ecological response of a multi-purpose river development project using macro-invertebrates richness and fish habitat value

Marc Pellaud

It has been acknowledged that river morphology and hydrology have been intensively altered due to the anthropic demands in floodplain land use and management, flood protection, promotion of navigability or energy production. Rivers were transformed in water highways, having lost contact with their surrounding floodplain as well as the plethora of ecological processes and occupants once thriving in these ecotonal zones. The identification of this emerging threat of morphological and hydrological alteration on ecological integrity adds further complexity in the exploitation of hydrosystem resources. These resources are heavily coveted and guarded by different lobbies each having strategic views on future project development. Stakeholders may want to promote hydro-electricity, ecologists a natural reserve, communes may wish to have an increased flood protection and leisure promoters a nautical center. As a result, the proposition of a river development project is certain to face opposition of one party or the other. The motivations of this dissertation are anchored in this context, where various and sometimes conflicting potentials for hydrosystem exploitation remain. This works aims at contributing scientifically to an innovative approach at the conception phase of a multi-purpose river development project by developing the ecological module to be implemented in the general project's optimizer. The SYNERGIE project hypothesis is that it should be possible to identify a synergetic pattern joining the interests of ecological integrity, flood safety, energy production and leisure development. Such a multi-objective river development project would stand more chance of acceptance. This dissertation focuses on the ecological aspects of such a river development project and an application on the regulated Swiss Upper Rhone River. Is expected an ecological answer to a river development project design / management which has to be compatible with Heller's Heller (2007) general SYNERGIE project optimizer taking into account all the project poles. The system of interest is composed of a buffering reservoir of ca. 1 km2, a run-of-the-river dam, a hydro power-plant, and an artificial river ensuring longitudinal continuum. The primary part of the work consisted in an extensive literature review on system understanding, anthropic alterations and quality assessment / prediction tool available. The approach consisted of two levels (1) the general ecological considerations to be followed at the project reservoir scale and (2) the measure of the downstream ecological response through modeling. General ecological considerations at the reservoir scale were the implementation of an artificial river ensuring longitudinal connectivity, implementation of artificial ecotonal boosters and the allocation of a sanctuary zone with limited public access. The downstream measure of ecological integrity was based on the choice of three taxonomic groups of macro-invertebrates and four ecological guilds (groups) of fish. Mayflies (Ephemeroptera), stoneflies (Plecoptera) and caddisflies (Trichoptera) richness were predicted using simple hydrological and morphological covariates (i.e. substrate, current speed,...) coupled to system specific faunistic surveys. Bank, riffle, pool and midstream fish guilds habitat values were determined using existing methods. By using the simulation results of river development project scenarios as inputs, the ecological response (i.e. the measure of ecological integrity) was computed following the assumptions that high predicted macro-invertebrate richness and high guilds habitat values were linked to a high ecological integrity. An emphasis on the hydropeaking effect in relation with river morphology was performed on macro-invertebrates. They were found to respond well to hydrological and morphological changes induced by river development projects while the approach by fish habitat value encountered limitations in its applicability. Four multi-objective project scenarios were analyzed, (1) the actual state of the Swiss Upper Rhone River at the Riddes site (VS), (2) a hypothetical hydropeaking mitigation project, (3) a hypothetical bed widening project and (4) a hypothetical bed widening coupled to hydropeakaing mitigation project. The actual state resulted in the worst measure of ecological integrity, with comparable results for hydropeaking mitigation project or the bed widening project. The highest measure of ecological integrity was observed for the coupling of hydropeaking mitigation and bed widening. These results showed that a multi-purpose project can increase the ecological integrity of the Swiss Upper Rhone River, produce electricity, provide protection from floods and develop local leisure activities. The synergetic effect of the project could be measured by project acceptance. Nevertheless, our knowledge on the hydropeaking effect on hydrosystem should still be completed by more research in order to give more weight to the ecological implication of hydropeaking.

EPFL2007

Trust and forms of capital in business-to-business activities and relationships

Niki Hynes

The IMP group's ARA model, with its emphasis on interaction, captures social and economic dimensions of exchanges. We draw on it to compare three cases and assess how actors act in skilful and nuanced ways in mobilizing resources, given the very different norms of social and economic capital. We prioritize action ahead of structure and, given the inherent uncertainties that actors encounter in connection with resources, argue that trust is a cognitive and heuristic dimension of action, distinct from resources, actor-bonds and social capital. We conclude that for business practice, managers should be mindful that in order to trust others, they need to act in the distinct realms of social and economic capital, tempting though it is to interpret and measure the costs of actions economically. (c) 2010 Elsevier Inc. All rights reserved.

Elsevier2010

Fonctionnement et gestion des aquifères alluviaux de haute altitude

The Haute Sarine alpine valley is located at an average altitude of approximately 1'000 to 1'200 masl. It was formed in its southern part up to the area of Gstaad to the favour of a typical North-South tectonic fault according to the main structures of the Préalpes, then followed normal fault striking East-West to end up on the rock bolt of the Vanel hill. The late and postglacial period was marked by the deposition of glaciolacustrines, glaciofluviatile and flurecent fluviatile sediments which have filled the ice free valley bottom probably starting from a period older than the Bölling-Alleröd interstadial. The depth of this overdeepening varies between 20 and more than 50 m of depth. Drillings which we carried out could document series of typical glaciolacustrine sediments. The implementation of several geophysical survey methods (resistivity, seismic refraction and reflexion, well logs and pumping tests) enabled us to analyse several sources of information which we confronted between them in order to produce a 3D model of the quaternary deposits and their hydrological properties. Most of these sediments are relatively quite permeable and build a free groundwater reservoir that we subdivided into 3 parts. The basin of Gsteig in the south is closed, the valley having been blocked by a massive landslide that probably occurred in several successive stages starting at the first climate improvements. The second part, the basin of Feutersoey has not been retained as a potential important hydrogeologic resource based on our preliminary investigations. The last basin, that of Gstaad-Saanen is the largest and thickest. It is also in this basin that most of the tourist and industrial activities of the area are concentrated. The observation network was established in order to characterize the groundwater flows enabling us at the same time to carry out piezometric measurements and chemical as well as and bacteriological analyses. We also carried out a δ18O isotope analysis campaign. The whole of these approaches highlighted the particular characteristics of the groundwater recharge. The groundwater system is mainly fed by the Sarine and the precipitations infiltration. We also located an underground karstic feeding of evaporitic type. We finally propose a groundwater management and protection concept adapted to the particular situation of the Sarine alluvial mountain aquifer system on both quantitative and qualitative aspects. The high altitude alpine groundwater catchment areas such as the Haute Sarine represent as a whole a quality resource, with high potentials yet to be defined on a larger scale, for example by applying numerical modeling and by organizing and maintaining long term observation networks that will enable us to define a sustainable groundwater resource management within the alpine area.

EPFL2000

Fonctionnement et gestion des aquifères alluviaux de haute altitude

EPFL2000

Ecological response of a multi-purpose river development project using macro-invertebrates richness and fish habitat value

Marc Pellaud

EPFL2007