Talk Announcement: Rémi Lemoy "The city in 2 and 3 dimensions: monocentric analysis and scaling of land use and population density" on monday the 21th november 2016 in Besançon

 

The talk will take place at 14h on monday the 21th november at the ThéMA lab building (3rd floor building D).

 

Remi Lemoy

Rémi Lemoy

Researcher (Post-doc) at the University of Luxembourg

Publications: https://www.researchgate.net/profile/Remi_Lemoy

 

Abstract:

In this work we study the profile of land use and population density in European cities with respect to the distance to the city centre. We use the GMES Urban Atlas database, providing a precise description of land use at 5m resolution in the 300 major European urban areas (more than 100.000 inhabitants). We combine this dataset with population density from the Geostat population grid, which covers the whole of European Union with a 1km2 resolution. Population is allocated proportionally to surface and weighted by soil sealing and density classes of the GMES data.

We analyse the evolution with distance to the city centre of population density and of the share of land which is artificial. We analyse the scaling of these curves with respect to city population. We find that land use curves, in particular artificial land uses, tend to scale like the square root of city population. Population curves have roughly exponential shapes, as it has been widely modelled in the literature, although usually not based on land use and soil sealing data. Population curves tend to scale like the city population to a power of roughly 1/3.

These results allow us to propose a simple monocentric description of land use shares and population curves in a representative European city, whose size can be chosen based on the scaling relationships we obtain. This result is especially interesting, and of practical use, for the purpose of calibration and validation of monocentric urban models, that can differentiate (or not) housing from land and include interactions between non-developed and developed land.

Last Updated: Tuesday, 15 November 2016 13:14

Christophe Mimeur is defending his PhD thesis "The traces of speed between space and network - Geohistorical approach to the growth of the French Railway Network" on December 9th 2016 in Dijon

The defense will take place at the "Salle du Conseil de l’UFR Droit, au rez-de-chaussée du Bâtiment Droit-Lettres de l’Université de Bourgogne" (4 boulevard Gabriel, 21000 DIJON). This work was directed by Thomas Thévenin.

Defense jury

Corinne BLANQUART, Research Director at the IFSTTAR,

Anne BRETAGNOLLE, Professor at the University Paris 1-Panthéon-Sorbonne,

Valérie FACCHINETTI-MANNONE, Associate Professor at the University of Bourgogne-Franche-Comté,

Jordi MARTI-HENNEBERG, Professor at the University of Lleida, Spain

Thomas THEVENIN, Professor at the University of Bourgogne-Franche-Comté

Abstract

The interaction between space and network are frequently questioned in the academic literature, by asking the economical and demographical impacts of a new infrastructure, often studied at the scale of a project. This work aims to investigate the components of the interaction in both large spatial and temporal scales. The hypothesis is that the temporal depth and the national scale could bring new explanations. This work is based on the collect, the exploitation and the analysis of the large spatio-temporal database FRANcE (French Railway Network). It identifies all sections of the network since the 19th century and the population census. This database also contains the traces of the speed, which are novel information for network, and allows the accessibility to become a decisive variable in the explanations.

Rather than acquisition new data with an intensive phase of collect, we aim to build a methodological chain to study the two senses of interaction between space and network. It requires the adaptation of data structuration and analysis. The approach of this thesis consists on the growing modelling of the phenomenon, from the comprehension to formalization of data to the analysis, which requires the use of other disciplines. This work uses the graph theory to investigate the two senses of the relationship. It permits to study the network effect in the long run by diversifying the data to identify spatial and temporal ranges. It permits to study the impact of a pre-existing structure in the morphogenesis of the network, by using a dynamic model of network evolution, between diffusion and hierarchical organization. This work aims to understand the link between space and network, where the methodological tools can be adapted to other networks, other times and actual questioning.

Last Updated: Monday, 14 November 2016 14:53

Yohan Sahraoui is defending his PhD thesis on December the 1st 2016 in Besançon.

The defense will take place at UFR SLHSn rue Chifflet at Besançon on December the 1st 2016 at 14H30. This work was co-directed by Jean-Christophe Foltête and Céline Clauzel.

Defense jury

Marc ANTROP, Professor at the University of Gand,

Jacques BAUDRY, Research Director at the INRA,

Céline CLAUZEL, Associate Professor at the University Paris-Diderot,

Marianne COHEN, Professor at the University Paris-Sorbonne,

Jean-Christophe FOLTÊTE, Professor at the University of Franche-Comté,

Thomas HOUET, Associate researcher at the CNRS,

Abstract

Landscape is both a backdrop to the lives of human populations and a medium for the life cycle of animal species. Landscape changes induced by land-use and land-cover dynamics affect both these dimensions, the one aesthetic, and the other ecological. Because these rationales are usually studied within different disciplines, little research has been done into how the two clash or combine as and when landscape structures change. This work seeks therefore to model the spatial co-evolution of the aesthetic and ecological functions of landscape retrospectively using spatial metrics based on land-cover data. It focuses on changes in the urban fringes of two French cities (Paris and Besançon) over the last 30 years.

The approach attempts first to use land-cover data to model (1) the landscape preferences of a set of individuals and (2) the ecological connectivity of a set of animal species. Drawing on both multivariate statistical analysis and spatial analysis, the core of this work consists in investigating how the two functions have evolved in convergent or divergent ways over time. The results provide fresh insight into the relationship between landscape aesthetics and landscape ecology and raise questions about the value of spatial modelling for a landscape management approach that endeavours to reconcile the preservation of residents’ living environments and the conservation of biodiversity.

Last Updated: Monday, 14 November 2016 11:05