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The need to adapt and increase the resilience of urban areas regarding the issues induced by urbanization and climate change effects (e.g. floods, Urban Heat Island, pandemics, etc.), has led to propose several strategies as the Natural-Based Solutions (NBS), which are focus on restoring natural processes such as infiltration and evapotranspiration (ET) in urban areas. In consequence, the increasing interest on NBS installation (highly supported by the H2020 program of the European Commission) by urban planners, decision-makers, researchers and the residing population has conducted to question the most efficient ways of NBS deployment. In this context, the urban dynamics (e.g. population density, land use patterns, transport network, etc.) and the distribution of green areas at different spatial scales play a key role that characterise the urban development in the territory.Based on the study of an urban agglomeration named Est-Ensemble, located at the east of Paris (France), this research aims to: i) determinate the fractal dimension of the built-up and green areas by using 2 different box-counting methods; ii) set the potential areas to install NBS, through the development of an iterative downscaling scheme over the built-up structure with the software Fractalopolis, and following a polycentric approach inspired on the urban form of Ile de France Region, and iii) assess the population access to the nearest green spaces and deficit of green spaces.Further, from local scale measurements of ET made close to Est-Ensemble agglomeration, the authors carried out a multifractal analysis of the ET data to better evaluate the observed scaling behaviour. This will be coupled with spatial approach developed above to evaluate the impact of temperature reduction of different land use scenarios. This research is partly supported by the French ANR EVNATURB project.

This paper studies the impacts of the construction of a new highway on the built-up land use dynamics in the southern neighboring area of Beirut in Lebanon, whereas the impact of transport infrastructure on land use dynamics has been widely studied, few examples are found for developing countries where data are not widely available. Moreover, it is difficult to assess the impact of the infrastructure among several external and internal factors. Areas of built-up land use in Beirut Southern entrance in Lebanon were extracted from land use classification maps for years 1985 to 2019 using 30 m resolution satellite reflectance images in ArcGIS software. To compute an accessibility index to the population, average car travel speeds were determined for major local roads and population distributions were collected for years 2004 to 2019. Results revealed that after the completion of highway’s construction, the development of built-up land use has increased by 13.9%, but also that the land use dynamics depends highly on the unexpected arrival of Syrian refugees between years 2011 and 2013. The results were analyzed with the help of several interviews of stakeholders.

sMonitoring and understanding the evolution of land use and land cover is a key factor for many environmental studies as well as for policymakers. Moreover, policymakers are interested in understanding the factors that have a significant impact on land use change. This paper analyses the dynamics of land use change in Lebanon between the years 1984 and 2019 and identifies the main factors behind this process. The use of LandSat satellite images enables the creation of land use maps at several periods and the monitoring of the evolution of built up areas as well as of green areas. Five periods emerge from this analysis, for which it is possible to propose explanatory factors, after an in-depth qualitative analysis. Within the framework of Structural Equation Models, a Confirmatory Factor Analysis is carried out to determine the impacts of several factors related to governance and financial data. Moreover, the urban sprawl is further investigated and explained by cultural, environmental, and infrastructural factors. The main results reveal that the development of built up areas is highly dependent on good funding conditions, whereas banking conditions and weak governance are correlated. The case of Lebanon presents specificities probably linked to historical and cultural considerations that deserve to be studied in future works. In the form of recommendations, new land use policies should be enacted to ensure sustainability in the form of an equilibrium between the urban development, from one side, and the preservation of natural resources and good environmental conditions on the other side. This could comprise the preservation of natural zones; the subsidization of the cultivation profession; and the encouragement of urban densification instead of horizontal sprawl.

The growth of the world’s population living in urban areas has led to change from natural to highly dense and impermeable landscapes. Moreover, the intensity and frequency increase of extreme event...

International audience; This research provides new evidence about the relationship between travel behavior, workplace diversification, and environmental impact in the United Kingdom using data from the National Travel Survey for the period between 2002 and 2017. The path analysis approach based on SEM handles both direct and indirect effects and allows for a comprehensive study of travel behavior, trade-off effects, and work and non-work trips. The results suggest that workplace diversification is often reflected by longer average distances for work trips, which are often associated with more remote residential locations. Findings also show that for some categories, such as teleworkers and home-based workers, trade-off effects are observed between work and non-work trips, which increase CO2 emission levels.

International audience; Limiting commuting trips in major cities is important from the environmental, social and economic standpoints. In order to design policies that aim to change commuting practices it is, however, necessary to have acquired a good understanding of the trips in question and their determinants. However, these trips have been subjected to very little study in the cities of developing countries. This paper is concerned with the Rio de Janeiro Metropolitan Area (RJMA), and sets out to test the influence of “classical” socioeconomic and spatial variables on the distance and duration of the commuting trips of the region's inhabitants, especially those with the lowest incomes. The main original feature of this research is that it includes jobs in the informal sector. The results show that, all other things being equal, commuting distances and times are shorter for the informal sector, and people walk more from their homes to their place of work because jobs in the informal sector are more dispersed than jobs in the formal sectors. The notable exception is personal and household services for which employees (who are mainly women) live a long way from the city center where wealthy families (and their jobs) are concentrated.

In Rio de Janeiro, immobility or the share of people with no journeys on any given day is very high (46%). Immobility has a marked geographical dimension in what is a segregated city. But income has only limited explanatory power. The population structure, with high proportions of people who are not in the labour force and who are unemployed, accounts for the high levels of immobility in the poor districts. Although population structure effects prevail, spatial factors such as the severance effect also account for differences between districts. Indeed, Rio de Janeiro features many different types of barriers that affect immobility in several districts and for several population groups. These barriers may be physical or symbolic and perceptive. This study proposes therefore to identify the scope of those barriers as they affect immobility. Our findings from the latest household travel survey available for the metropolitan area of Rio de Janeiro (2003) illustrate the effects of the two types of barrier, physical or symbolic and perceptive, on immobility that more specifically mark out certain categories of individuals such as housewives, the elderly, the unemployed or poor workers. Conversely, the wealthier active population seems to be little affected by the two types of barriers under study. Lastly, our results show that social fragmentation does not lead to greater immobility of favela populations in the heart of rich districts, but on the contrary to increased mobility, especially for the working age population in employment or looking for employment.

International audience; TOD (transit oriented development) is a land planning approach that aims at developing harmoniously a transit network and the land it deserves both at the local and at the regional scale. It has been implemented successful in several large North and South American cities. Its transposition to Europe and small to medium cities is not straightforward, especially because European cities are much more dense than American ones, and transit is already well developed. However, TOD can also be considered as a means to coordinate existing land use and transport planning, and this is a major issue for all cities whatever their size or their density. Indeed, there is a co-production relationship between transport and land use, and the city development is systemic with many feedback loops between its subsystems. We show in this paper that a medium-sized city such as Besançon in France can benefit from a TOD approach for its development by designing scenarios and evaluating hem with a LUTI model.

Digital Terrain Models constructed from contour lines often contain artifacts originating from their construction from irregularly spaced height measurements. We evaluate and illustrate these artifacts and their impact on terrain parameters. We provide algorithms to correct them as much as possible, and propose a methodology to predict areas where uncertainty still remains because of these artifacts. The analysis of these artifacts enables us to derive qualitative parameters such as "likely over-estimated", "likely underestimated", and "with no significant bias" on the DTM. Our method provides a qualitative description of local uncertainty, which is often more relevant for geographical applications than global quality parameters.