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Doctorat financé par Département Développement Durable d’
Business Sites Gardens as opportunity for Urban Biodiversity ?
Hortense SERRET
September, 26th
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Woods Agriculture Water Open urban areas
Individual habitat
Collective habitat
Business activities
Facilities Transport
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Evolution of land uses in Paris region between 1982 and 2008
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Few studies about business site green spaces
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o How are Business Sites Gardens spatially organized and what kind of contribution do they have for urban connectivities ?
o What are their ecological features ?
o How employees see those Gardens ?
Research questions
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o Every green spaces around business sites buildings
What is a « Business Site Garden » ?
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8 700 ha in Paris region
Very heterogeneous sizes, until more than 100 ha
15 % of housing gardens areas
23 % of parks and gardens
Double of wasteland surfaces
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o Every green spaces around business sites buildings
What is a « Business Site Garden » ?
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© Hortense SERRET
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Spatial organisation of Business Sites Gardens in Paris region
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Proportion of business site gardens per urbanization classes
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Urban center Dense urban Suburban Périurban
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Importance of business site gardens compared to public gardens or parks
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o Graph theory • Nodes = Habitat patches
• Links
Leat-cost path
• Dispersion capacity of a model species
o Landscape metrics • Probability of Connectivity, PC (Saura et Pascual-Hortual 2007)
• Decomposition of PC (Saura et Pascal-Hortual 2010)
How Business Sites Gardens contribute to urban connectivities ?
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o Low contribution at global scale for global connectivities
o High contribution at local scale for global connectivities in suburban areas • Recent urbanisation with Activitiy Parks organisation
o Low contribution in area for connectivities compared to other green spaces (parks, housing gardens)
o Strategical location for connectivities : 10 % of business sites highly contribute to coherence of connectivities
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How Business Sites Gardens contribute to urban connectivities ?
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o A study of 56 business green spaces
o Two areas
• « South » area : high density of urbanisation, high land pression, few connectivities with other green spaces
• « Cergy » area : bigger green spaces, more open landscape
o 28 business sites on each area
Field observations
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Typology of habitats present on Business Sites Gardens
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Lawns Woods Wastelands Meadows
96 % 23 % 14 % 11 %
© Hortense SERRET
© Hortense SERRET
© Hortense SERRET
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o Conservation
• Plants
94,2 % of indigenous species
14 % of urbanophobic plants
10 % of species are considered ‘in regression’ ou ‘vulnerable ‘ in the region
• Birds
Presence of birds species which population are declining at national scale
o Fonctionnality • 70 % of entomogam plant species
• Extensive management promotes butterflies sensitive to urbanisation
• Contribution to bats activity
• Presence of birds considered as indicators for green connectivities
Contribution for Conservation and Fonctionnality of urban biodiversity
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Cynoglossum officinal
Achusa arvensis
Pyrrhula pyrrhula Carduelis cannabina
Maniola jurtina
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o Work in progress…
o Questionnary to employees • Fonctions of Business Sites Gardens
• Uses of Gardens
• Appreciations
• Are Fonctions, Uses and Appreciation linked to presence (or no-presence) of Nature ?
Contribution for employees representation of Nature ?
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© Hortense SERRET
© Hortense SERRET
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A project to involve compagnies in the promotion of biodiversity on their sites
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o Promotion of extensive management on business sites
o Biodiversity monitoring to evaluate efficiency of practices changes
o Partnership with scientific community to share data
Doctorat financé par Département Développement Durable d’
Thank you !
Any questions ? [email protected]
