Poudcvignc Et Al / Landscape and Urban Planning 38 (1997) 93-103
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PDF hosted at the Radboud Repository of the Radboud University Nijmegen The following full text is a publisher's version. For additional information about this publication click this link. http://hdl.handle.net/2066/27993 Please be advised that this information was generated on 2021-09-27 and may be subject to change. LANDSCAPE AND URBAN PLANNING ELSEVIER Landscape and Urban Planning 38 (1997) 93-103 « Dynamics of rural landscapes and their main driving factors: A case study in the Seine Valley, Normandy, France Isabelle Poudevigne a, Sabine van Rooij b, Pierre Morin a, Didier Alard a- * a Lcibomtaire d ’Ecologie, UFR Sciences, Universite de Rouen, F-7682J Mont Saint Aignan Cedex, France b Department of Environmental Studies, University of Nijmegen, Post bus 9010, 6500 GL Nijmegen, The1 Netherlands Received 2 October 1996; accepted 17 April 1997 Abstract Land cover and landscape patterns dynamics over a 25 year period are analysed for a case study in Normandy. With the help of cartography, GIS and multivariate analysis, factors contributing to landscape structures and changes are studied. The results point out three main driving factors responsible for the landscape change: Agricultural practices which lead to intensification of some areas and abandonment of others, urbanisation which modifies the structure and organisation of the landscape, and finally, as factor of stability comes the conservation policies which check these changes in certain zones, Despite this last factor, the global resulting impacts are, up to now, the progressive disappearance of the organisation of the sites landscape. © 1997 Elsevier Science B.V. Keywords: Rural landscape; Landscape dynamics; Landscape organisation; Cartography; Multivariate analysis; Urbanisation; Agriculture; Nature conservation; Seine Valley; Normandy 1. Introduction All these studies using very different tools have pointed out different causes and effects of landscape Analysing landscape patterns and dynamics is one dynamics. The main driving factors have been identi of the main goals of landscape studies, whether on fied as agriculture intensification (Green, 1990; an ecological basis or a geographical one. The first Harms et al., 1984) or urbanisation (Phipps et al., scientific aspect deals with modélisation of ecologi 1986) in the context of local or national policies cal functioning and processes at the landscape scale. (Kubes, 1994; Lipsky, 1992; Meeus, 1993). (Turner et al., 1990). Landscape changes are also an The present paper deals with rural landscape dy important part of environmental earth dynamics, also namics in the Normandy region and specifically in called global changes (Vitousek, 1994). The second the Seine valley. The landscape of this valley is scientific aspect is mostly involved in studying how historically modelled by agriculture and offers a very rural human societies model their landscape and their specific landscape pattern (natural mosaic of wet environment (Spedding, 1984). lands, ploughed areas and chalk grassland across a topographical gradient). Today this area and the site of St Martin de Boscherville in particular, is subject * Corresponding author. Tel.: +33-0235146903; fax. + 33- to the intensification of agriculture which holds a 0235146655; e-mail: [email protected] large part in explaining the landscape dynamics. 0169-2046/97/$ 17,00 © 1997 Elsevier Science B.V. AU rights reserved. PII SOI 69-2046(97)00025-X 94 ƒ. Poudevigne et a l,/Landscape and Urban Planning 38 (1997) 93—103 Many outside pressures also contribute such as the that it is a microcosm of most of the habitats present growing urbanisation of the nearby town of Rouen or in Normandy. the protection measures of the Regional park it is part of. As a changing rural site, subject to such pressures, St Martin offers an complete case study 2. Methods for the assessment of rural dynamics and it’s driving factors (Alard and Frileux, 1992). Data used to describe the St Martin landscape and We have tried to monitor landscape dynamics in the driving factors behind the dynamics observed, this area in order to assess and to localise the changes. are detailed in Table 1. To analyse these different In a second stage we have tried to assess the main data and to make calculations for comparing them, driving factors of these dynamics: On one hand the use was made of the Geographical Information Sys presumed driving factors of change (agriculture and tem Macmap 1.3 (Klik Développement, France). The urbanisation) and, on the other, a presumed factor of maps and the aerial photographs were scanned and stability (the various site protection and nature con lead directly into the Macmap program. Each object servation systems effective on the site). of those maps (point, line or surface) pointed out by Macmap was identified. As concern the aerial pho 1.1. Study area tographs, eight major landcovers were distinguished. A series of thematic cartographies (or files) of the The site chosen for this study lies on the banks of site were thus obtained: soil types, landcover in the Seine, west of Rouen. The area comprises 4100 1964, landcover in 1989, plot limits and linear struc ha and corresponds to 4 municipalities: St Martin de tures. To visualise the organisation and changes of Boscherville, Quevillon, Henouville and St Pierre de the St Martin landscape between 1964 and 1989, a Manneville, thus its boundaries are administrative representative transect (i.e., where most of the differ limits (Fig. 1). The interest of this site lies in the fact ent habitats present are represented) of these above Hertouviile StMnrti^de Boscheville transect localisation Quevillon "St Pierre de Miuuieville Fig. 1. The study site of St Martin de Boschervillc: General situation in Normandy and grid presentation. The transect studied is localised on four grids at the level of Quevillon. L Ponderigne et al. / Landscape and Urban Planning 38(1997) 93-103 95 Table I Nature and source of data Nature of data Source Date Natural features Topographical map scale 1:25000 (IGN) 1982 Geological map scale 1:50000 (BRGM) 1964 Landcover features Aerial photographs (IGN), scalc 1:20000 1964 and 1989 Agricultural structures In situ survey of 10 farms on 330 ha situated in Henouville and St Martin, 1994 comprised in 36 cells of the grid. Urbanisation Value of the Habitation variable expressed by the analysis 1964 and 1989 of the aerial photographs (IGN) Protection devices Map of the ZNIEFF inventory (CDM-DRAE) 1994 Map of the POS inventory from (DRAE) 1994 mentioned maps was selected. Their visual compari H(V)~ —Epilog2pi and pi is the proportion of the son already provides an interesting global approach. landcover i variable, H(V) is thus the diversity These files were then used to calculate the organi (Shannon index) on the area, and where H(VSj) is sation of the landscape in different years and to the diversity (Shannon index) on each soil type Sj. assess spatial correlations between the driving fac- Some of the changes monitored are not at plot tors and the dynamics observed. The organisation scale and some data are on different frame such as index chosen for that purpose was index C defined spatial diversity (inter plot measures). Thus, in order by De Pablo et al. (1988) which is an index of the to take such data in consideration or to assess trans information theory group. Based on the amount of formations linked to the structure of the landscape, the relative abundance of land cover types in the the griding method was chosen. The site was thus different soil types, this index indicates the degree of divided in 134 cells of 600 m by 600 m for which mutual connectance between these sets. It is given by the value of variables concerning either the land the formula C = (H(V) - H(VSj))/H(V) where cover, the soils, the structural characteristics, or the agriculture were recorded (Table 2). Structural mea Table 2 sures conditioned the size of the cells: They could List of the variables used for the description of the 134 microland not be realised on smaller squares since the cells scape ceils and the multivariate analysis would have had a uniform landcover, and could not Land cover features (values for 1963 and 1989) have been realised on larger squares since the cells H Habitation would have had too similar landcover proportions. 0 Orchard Treatment of these matrix (134 cells X groups of F Forest (Silviculture and forest) variables) by multivariate methods provided thematic C Crop G Grassland (including chalkgrassland grided cartographies of the site. PCA (principal com and abandoned grassland) ponents analysis) and HAC (hierarchical ascending T Hedges classification) were realised with STATITCF soft ware. Ecological pattern features (values for 1963 and 1989) L Length of ecotone boundaries D Diversity (Shannon) R Richness 3. Results Topographical and lithological features: ‘natural’ features 3.1. The ‘natural o rganisation o f th e lands cape: A n / Slope (in %) agricultural heritage A Altitude (in rn) N Orientation (in °) The St Martin site at simple observation offers S Lithology (type numbered) DW Distance in m to the water even today a very organised picture. This structured DF Distance in m to the nearest road landscape is the heritage of many years of an agricul ture bent to the natural characteristics of the land. So 96 /. Poudevigne et al. / Landscape and Urban Planning 38 (1997) 93-103 as to visualise this organisation in 1963, the chosen sis by PCA of the matrix crossing the 9 landcover transect of the site is represented according to both and ecological pattern features (Table 2) by 134 ceils soil characteristics and landcover features (Fig. 2). (or individuals) in 1963 brings up two main axis Their appraisal points out that landcover and soil (added rate of representation of 57.6%). The First types follow a topographical gradient.