Evaluer les attitudes lgard des dpts alluviaux et

Evaluer les attitudes à l'égard des dépôts alluviaux et des inondations The evaluation of attitudes towards alluvial deposits and floods CNRS - UMR 5600 Hugard de la Tour, Inondation à Chamouny (1855)

L’Isère (Cliché : Philippe Belleudy) « (…) des plages de sable, des archipels de galets bordent son lit principal, pareil à quelque grand miroir qui magnifie ce qui vient s’y refléter » . Bergounioux « Flot, requiers pour ta marche un galet au sol terne Qu’à vernir en ta source au premier pas tu perdes » . F. Ponge, Le parti-pris des choses. CNRS - UMR 5600

Content 1. The attitudes towards riverscapes 2. Perception of braided river landscapes 3. Floods in local newspapers CNRS - UMR 5600

CNRS - UMR 5600

CNRS - UMR 5600

CNRS - UMR 5600

Plan 1. The attitudes towards riverscapes 2. Perception of braided river landscapes 3. Floods in local newspapers CNRS - UMR 5600

Due to the present degree of environmental alteration along the Magra River, the need for sustainable sediment management is urgent. It is therefore important: - to understand how local stakeholders perceive a river channel that is rich in gravels, - to better evaluate whether or not they will support proposed braided channel restoration projects. CNRS - UMR 5600

Subject type Landscape features Data collect References CNRS - UMR 5600 Expert Psychophysical Cognitive Experiential Trained observer Respondent respondent Perceived physical features (feature, clarity, depth…) Participant observer Quality and preference (beauty, danger…) Ignitiating observer Everyday experience (familiarity, sociability…) Artistic, ecological and development principes Structural analysis Griselin, 2004 Huang, 2000 Cossin, 1999 Mosley, 1989 Daniel, 1983 Questionnaire Field Photo. , diapo. Video Campbell, 2002 Lekagul, 2002 Faulkner, 2001 Smith, 1995 Asakawa, 2004 Eisler, 2003 Ryan, 1998 Gregory, 1992 Brown, 1991 Interviews Auto. Photo. Literature and art. Nunneri, 2004 Dakin, 2003 Yamashita, 2002 Chételat, 2001 Michelin, 1998

Postulat: The visual features of riverscapes have an influence on the evaluation and behaviour of observors. Ten photographs of the river were shown to each participant depicting: -different proportions of water, vegetation, and mineral bar, - and different sizes of gravels. CNRS - UMR 5600

Five distinct groups of participants (total n=127) - Students attending college near the Magra River, - Students attending college far-away from the river, - People with a scientific understanding of river ecosystem function, - Local river managers working for the government watershed authority, - and other Magra River users. CNRS - UMR 5600

The evaluation of riverscape characteristics ü Three quantitative variables: Unpleasant Aesthetic quality 0 Beneficial uses of the river Need for active river management Pleasant 10 Visual analogic scale (VAS) CNRS - UMR 5600

The evaluation of riverscape characteristics ü Two categorical variables: the categories of uses to which the riverscape shown would be most suited 1 – no activity; 2 – fishing; 3 – swimming; 4 – navigation, 5 – relaxation, 6 – gravel mining, 7 – hydroelectric generation, 8 – domestic/agricultural water withdrawal, 9 – nature conservation) la caractérisation de l’intervention envisagée CNRS - UMR 5600

The evaluation of riverscape characteristics ü Two categorical variables: the categories of uses to which the riverscape shown would be most suited; suited the appropriate types of management activities for each riverscape: 1 – no management, 2 – improved landscaping, 3 – wildlife protection, 4 – bank stabilization, 5 – channel cleaning, 6 – engineered structures CNRS - UMR 5600

Surface area of each photograph (A through J) occupied by water, vegetation, and sediments, and the visually-assessed grain size classes of the sediment shown (0 - no sediment, 1 - gravel, 2 - pebbles, and 3 - large boulders) Water (%) Vegetation (%) Sediment (%) A 42. 25 45. 99 0. 53 0 B 0. 53 8. 02 52. 41 1 C 21. 93 5. 35 34. 22 1 D 26. 20 40. 91 23. 80 2 E 1. 07 37. 17 61. 50 3 F 24. 33 10. 70 33. 96 2 G 60. 16 15. 51 2. 14 1 H 15. 51 24. 60 39. 57 3 I 12. 03 28. 61 32. 62 1 J 59. 36 9. 89 11. 76 1 Photograph CNRS - UMR 5600 Grain size classes

Correlation Matrix (calculated with average Bravais-Pearson coefficients) for the survey response variables (aesthetic value, beneficial uses, and needs for management action) and the landscape components (area occupied by water, vegetation, and mineral bar). Significant values with p < 0. 05 are in bold type Aesthetics Uses Management Water Vegetation Mineral Bar CNRS - UMR 5600 Uses 0. 964 Management Water Vegetation Mineral Bar -0. 904 0. 759 0. 155 -0. 702 -0. 944 0. 868 0. 022 -0. 805 -0. 899 0. 069 0. 827 -0. 101 -0. 916 -0. 121

CNRS - UMR 5600

CNRS - UMR 5600

CNRS - UMR 5600

CNRS - UMR 5600

CNRS - UMR 5600

CNRS - UMR 5600

– – – – – l Chosing photos / drive perception Show real risky versus no risk situations Very nice pictures Small numbers of photos contrasted level of gravels in natural riverscapesand then photos with impliedgravel associated risk and then a second set of photos like the first (hyp. effect of phot order) Very much related to the time since flow events (memory effect). Two different places one with a recent big flood, one without. Use expert jugement as a ref. Risk? Riverscape with eroding banks (natural, with a house), vulnerable infrastrcuture (culver), bridge (public interest), house (private interest). Identification / risks Triplate photos / braided rivers with fine sediment implicting aggradation, gravel bar (implication of potential instability), cobble / paved channels. How people perceive risk through sediment process (torrential fans – may think house at risk far from the site) Questions – Distance to the closest river – If this house is sell, will you buy it? Will you be safe in this house? – Would you like to live there? – Divergence of the managers? Do you simply survey citizens? Other groups? – Natural or man-influenced? – More information that you want and real questions. l – CNRS - UMR 5600 3 questions? Safe/dangerous, Aerial photos. Where would you built your house. Where would it be risky to live? Oblique photos + gravel bars / far

Intra-group variability of the scores attributed to each of the survey response variables CNRS - UMR 5600

Categorization of beneficial uses recommended by survey respondents for each photograph CNRS - UMR 5600

Categorization of management actions recommended for each riverscape photograph CNRS - UMR 5600

Elements of discussion In terms of riverscape perception: -The influence of water on landscape evaluation - What is natural is not always aesthetics - The preference for maintained nature (rather than wild and regulated nature) -The role of familiarity - A difference between local/expert knowledges In terms of restoration project: - Consider the archetypes that influence public as well as decision makers - Promote campaigns of environmental education to explain the objectives CNRS - UMR 5600

Content 1. The attitudes towards riverscapes 2. Perception of braided river landscapes 3. Floods in local newspapers CNRS - UMR 5600

CNRS - UMR 5600

CNRS - UMR 5600

Le Crestois Le JDD 1981 CP 168/19 CP 176 D/8 2008 CP 168/51 CP 168/52 CP 176 D/26 140 articles : - 68 in Le Crestois - 72 in Le JDD CNRS - UMR 5600

CNRS - UMR 5600

Presentation of each article Article Newspaper Year Season Nature Writer 1 … Statistics with R Textual data analysis : ALCESTE and TXM GIS : places quoted (communes, rivers, catchment) CNRS - UMR 5600 Evocated stakeholders Uses Places

Stakeholders form a system characterized by different uses - stakeholders quoted - 40% users - 31% politicians - 21% riverside people - uses of the river - 51% production - 42% protection CNRS - UMR 5600

Stakeholders form a system characterized by different uses - production - quoted : farmers and riverside people - natural condition brutality and damages - protection - quoted : quarrymen - prevention acts - leisure activities - anglers CNRS - UMR 5600

Crisis and memory - Hydrological extremes and article distribution - 4 years without articles - A mean of 5 articles per year - the role of floods and the maximum of articles - What is the influence of the season? - autumn and spring - winter and summer CNRS - UMR 5600 - crisis and management 1994, 2003 et 2005

The crisis and its temporal management - 2 groups : the crisis and its immediate management (physical and temporal management) / the resilience of the system (to prevent a new crisis from happening) CNRS - UMR 5600

The most quoted - dams, dikes … and others works of civil engineering - restoration and maintenance A spatial variability A temporal variability CNRS - UMR 5600

A spatial variability Each subcatchement focuses on its subcatchment - Two different communities in a same basin - Which integrated management is then possible ? - CNRS - UMR 5600

The water territory (Ghiotti) and the risk territory - Identify the risk places - An archipelagic geography - Some discontinuities CNRS - UMR 5600

The Drôme as a management model Versus the floods as a crisis… -The time of management and political decisions (PPRi) - Two subcatchment (upstream and downstream) because of - different playors - different uses of the river - a political choice but some local adaptations… - Different places - the alea is not the same everywhere - the urban communes are more quoted but … - - a. UMRspecific place the Ramières… CNRS 5600

A diachronic approach - The repetition of alea and the more quoted places - An environmental disruption - the difficulty of fixing the flood causes - some stakeholders with different aims - a system resilience : which management of the crisis? - memory : exemplary floods, memory lapses, places which are forgotten CNRS - UMR 5600

La presse locale, une bonne source d'information ? A) Des biais importants : une échelle territoriale restreinte et parfois peu significative (Caron et Torre, 2005) la diversité du métier de journalistes (Bucher et Strauss, 1961 ; Neveu, 2004 ; Ruellan, 2005) l'incomplétude de l'information (Vicard et al. , 2005) et la partialité du choix des événements (Caron et Torre, 2005) les filtres culturel et idéologique, ainsi que la ligne éditoriale (Grawitz, 2001; Allard, 2005) B) Les atouts : une diffusion considérable et la quasi-exclusivité de l'information locale (Torre et al. , 2005) le reflet des attentes du public (Bourdieu, 1966 ; Grawitz, 2001) un support pour les débats et une source pour l'étude des conflits (Caron et Torre, 2005 ; Torre et al. , 2005) des archives propices à l'analyse d'événements (Sautter, 1994 ; SPOTTER, 2005), mais aussi à l'étude diachronique des inondations et des représentations et politiques publiques associées (Allard, 2005) CNRS - UMR 5600

Perspectives A) Floods in newspapers (Isère basin) Drome catchment: 100 articles in local newspapers (Emeline Comby) Isere catchment through Le Petit Dauphinois and Le Dauphiné Libéré from 1880 to 2010 (Silvia Flaminio, Master 1) B) 20/30 entretiens semi-directifs sur l’Isère (risque inondation) Þ experts, managers, practitioners, local decision-makers C) The perception of gravel bars by public and expert Which variables in the set of photographs? Which evaluative features? Which questions about floods to better understand the spatial and temporal framework of riverine landowners? CNRS - UMR 5600 Le Crestois, 1984

CNRS - UMR 5600