Group 8: Characterization of determinant factors of landscape evolution

Transcription

1 Urban Morphology and Landscape Integration Professor Dr. Jacques Teller Group Adivsor: Ahmed Mustafa Final Report Canton of Sankt Vith, Wallonia Group 8: Characterization of determinant factors of landscape evolution Fernando Puente (Coordination) Jorge Falcón (Data Management) Timothée Konan (Communication) February May 2016 University of Liege - Academic year

2 Contents 1. Introduction An insight to the rural milieu of the Belgian Eifel The broader context Objectives Methodology Description of the process Interpretation of Coefficients (β) Scenarios Previous Considerations The three scenarios Global Diagram (Schéma Macro Level) The green element The mobility element The clusters Local Analysis and Development Proposal Meso Level The Micro Level Proposal in detail Comments about other nodes Conclusions & Recommendations Bibliography

3 1. Introduction The present work aims to understand the dynamics of the Belgian Eifel territory in terms of how the human settlements have been developed. This study analyses through mathematical and spatial modeling different factors that have influenced the urban coverage changes through time. It also pretends to project scenarios of possible future development through the prediction of how the urbanized areas could grow, depending on how the incidental factors are managed, as well as how a prospective policy and norm could be exercised. Moreover, it pretends to illustrate at the most local scale, how this possible ways of development can be executed by residents and policy makers An insight to the rural milieu of the Belgian Eifel The study departed from a field visit and the collection of images of the territory to grasp a sense of what was the state of the situation. Even though the winter snow did not let reveal at first other moments of the landscape of the visited sites it still let the students have an initial idea of the rural character of these places. The above captured panoramic images portrait the municipalities of Amel and Butgenbach, respectively. They represent the current spatial transition period and reveal some of how the territory works. The built land coverage with different densities also shows diversity of building heights (two, three or four floors). Further horizons incorporate forests and open spaces which were not clear about whether their use was for pasture, ranching, agriculture or other economic activities or the lack of them. Certainly, the Belgian Eifel region is a prospect that can develop its potentialities. The rural spirit of the territory is its most valuable characteristic. At the same time, it shelters a number of inhabitants that not only can keep their good quality of living, but furthermore, they can enhance it and be more efficient and sustainable communities at the same time. A mostly rural territory assumes the challenge of preserving its natural landscape, while offering adequate infrastructure for its present and future inhabitants. 3

4 1.2. The broader context The Belgian Germanophone micro-region, while belonging to the Walloon region, it is highly linked culturally and somewhat functionally to the two neighbors beyond its adjacent national border (Germany and Luxemburg). As the below map shows, the micro-region stands distant in 50 Kilometers or more from other important cities such as Liege, Aachen, Cologne, Bonn and Luxemburg. This distance corroborates the rural character of the Belgian Eifel. This map also helps to illustrate what, further ahead in this document, are considered as determinant factors for settlements growth. Some of these factors are the effect produced by the international border, some medium size cities in Belgium, as well as the road network in it different hierarchies Objectives After the characterization of determinant factors of settlements evolution, urban growth scenarios modelling will contribute to propose changes in the structure and development patterns of the Belgian Eifel in order to achieve the following objectives: 1. Enhance sustainable development for the territory in terms of human settlements growth and their rural environment towards Achieve a balanced, organized and structured territory through a development model 3. Preserve a rural atmosphere while consolidating local communities in compact growth 4

5 2. Methodology 2.1. Description of the process First, a revision of the provided material was revised to understand its contents. Manuals and reference works were also revised in order to have a clearer idea of what was going to be needed. Departing from the available data, the group was able to determine which would be the factors for settlements grow that were going to be analyzed. Later in this document, those are described in detail. An initial operation was to measure the changes that occurred between the years 1990 and Particularly, the changes for the Built Area (red in the maps), defined by the CORINE project (European Environment Agency, 1996), experienced an increase of 970 hectares in these ten years. It seemed interesting for the group to see that the built class was the only one that increased, while other classes increased in some areas, but also decreased in some others. All the input data (particularly the ones that were available in vector format) was rasterized in a tiff format image file that was based on a grid of squared cells of 100x100 m2. All the input data was set in this grid format in order to be comparable and interoperable later with the software. A LOGIT statistical model was applied based on the grid of 100x100m2 considering the urban coverage difference between the years 1990 and The urban increment was considered as the dependent variable which would vary depending on 8 variables: a. Slopes 5

6 b. Closeness to Motorways c. Closeness to Regional Roads d. Closeness to Provincial Roads e. Closeness to Municipal Roads f. Closeness to Medium Size Cities g. Closeness to the International Border h. Zoning meant of built space The model resulted in a suitability map, which shows for each cell case a level of suitability of that cell to be a built space. In the following map (the suitability map) the darker areas are more suitable to be urbanized, as opposed to the whiter ones, the least likely to shelter urbanization. Some analyzed driving factors: the road network, as well as the international border are also represented in the map. The LOGIT analysis also delivered coefficient values for the variables in order to know which of them are more influential. The function that represents the analysis could be understood as follows: Where: Y = α + β 1 X 1 + β 2 X 2 + β 3 X 3 + β 4 X 4 + β 5 X 5 + β 6 X 6 + β 7 X 7 + β 8 X 8 Y is the dependent variable, in this case the urban growth (represented by 1=urban, or 0=non-urban) α is the intercept 6

7 β n is the coefficient, whose absolute value determines de incidence of the variable that is affected by it, compared to the other variables X n is an independent variable The suitability map was the base to build a Cellular Automata model that considered the suitability for changes and the neighboring cells as conditions to predict yearly changes in urban areas up to the year The number of changed cells (hectares, considering that each cells measure 100x100 m2) could later be manipulated in order to define growth scenarios. The software packages that were used were Matlab 2015b for modelling and QGIS and ESRI ArcMap for map processing and visualization. Mr. Ahmed Mustafa assisted the group in order to learn how to manage these tools, as well as to help run the modelling and correcting the script Interpretation of Coefficients (β) The following table explains the interpretation of each of the coefficients that influence its corresponding variable. The ROC value of the operation was , which means that it is quite likeable that the model is doing a correct analysis. The value of the intercept does not really have a particular meaning. Negative signs in the table, particularly for the roads, represent the opposite effect, i.e. the less distant the cell is from the analyzed road the more suitable is that cell to be urbanized. The opposite effect has the international border, for which the model shows that it is more suitable to be urbanized areas far from it. The following diagram illustrates graphically and proportionally the strength of influence and the order in which each variable promotes new urban growth in the canton. 7

8 Coeffi/ Variable Name Values Interpretation Intercept α β 1 Slope Close to zero, has little influence. β 2 Distance to Motorways Growth is moderately distant from Motorways. β 3 Distance to Regional Roads Negative means the closer the higher growth probability. Little influential road class. β 4 Distance to Provincial Roads Negative means the closer the higher growth probability. It is the most influential road class (provincial) β 5 Distance to Municipal Roads Negative means the closer the higher growth probability. Second most influential road class. β 6 Distance to Medium Cities Belgium Close to zero, has little influence. Β 7 Distance to Border Growth is usually a little distant from the national Border, it has minor influence. β 8 Zoning This is the most influential factor for probable urban growth. Note: Roads categories are classified according to the site Autoroutes et Routes de la Wallonie (Service Public de la Wallonie, 2016) 8

9 Is it important to mention that the zoning, as the major driving factor for urbanization, has also been proved in other studies for the Wallonia region: "Generally, result reveals that policies and accessibility are the most important determinants of urban growth process" (Mustafa, Cools,, Saadi,, & Teller, 2015). The following histograms show the incidence of each road category. As illustrated in the diagram of determinant factors, the provincial roads have the highest influence amongst all the road categories followed by the municipal roads. The motorways (autoroutes) histogram shows that, even though there is a 7% of the new built area (probably industrial commerce or gas/service stations) in the 1990s that was done in 250 m. closeness to this category roads, most of the new built spaces are developed moderately distant from these roads with a small peak at the distance of 2 Km. This seems logical, considering security reasons and environmental impact of being too close to motorways. In the case of the regional roads there is clearly a settlement concentration at the distance of 2 Km. of these roads. Again, in the first kilometer distant from the Regional Roads the new built space is very scarce (around 7% of all the new built area in the 1990s). The reasons for this could be similar to the ones for the motorways case. The provincial roads histogram clearly demonstrates that 35% of the new built space in the microregion has appeared in the first 250 m. close to these roads. It also shows that gradually the amount of new built cells fade out as the distance to the roads increase. A similar effect to the provincial roads, although with a more abrupt fading out, has the case of the municipal roads. In this case it is also noted a sudden peak at the distance of 1250 m. from these roads. A speculation about this fact could be that in these areas there were more new buildings related to farming or other country activities. 9

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11 3. Scenarios 3.1. Previous Considerations To elaborate possible scenarios of human settlements growth for the Belgian Eifel region for the year 2030 two considerations were taken into account. The first one was the population evolution and projection delivered by official sources and measured in terms of number of people and number of households at the munipality level. Following there is a table that shows this evolution. POPULATION Amblève Bullange Butgenbach Saint-Vith Burg-Reuland TOT HOUSEHOLDS Amblève Bullange Butgenbach Saint-Vith Burg-Reuland TOT PERSONS/HOUSEHOLD 2,63 2,48 2,31 2,18 2,07 Source: (Service Publique de la Wallonie, 2016) Secondly, the reference of 970 hectares that grew with built space in the 1990s decade. This last reference datum let the group compare the modelled evolution, which has a linear character, to the recent situation represented by the satellite photograph (2014), which is illustrated in the following image sequence. When looking at the 2010 time step of the modelling (red shadow) the modelled growth seems to be already exaggerated compared to the buildings seen in the 2014 satellite photo, which may lead to the assumption that the urban growth in these micro-region is not growing as a linear function, but as a logarithmic one, instead. Unfortunately, the land coverage data for the year 2010 was not available to prove at which rate this behavior could be. 11

12 Additionally, there is an important reference defined by the Wallonian authorities that states as the following text determines: "In line with an ongoing work of the Walloon authorities, new residential areas called 'settlement cores' were defined. In these settlement cores, the housing density in 2100 should not be less than 20 householdsha 1 (objective of density), and no new housing may be built outside these settlement cores (objective of compactness). Moreover, the total area of settlement cores should accommodate housing for the expected population in 2100." (Beckers, 2013) Although the 20 households per residential hectare for the year 2100 is meant for settlement cores, it still represents an important reference for the scenario proposal for the rural areas. In 1990, the Belgian Eifel had an average of 0,73 households per urban area and in 2000 the number was 0,76 households per urban area, which are numbers challenging to raise, yet considering that the Belgian Eifel is a rural micro-region with little population growth and a relatively larger urban growth. 12

13 3.2. The three scenarios First Scenario: Urban Sprawl The first scenario considers the trend derived from the analysis made for the decade, at a rate of 970 new urban coverage hectares per decade. It is inefficient in terms of public services provision (networks, facilities) and it consumes land used before for farming or foresting. 13

14 Second Scenario: Parallel Growth In the second scenario settlement land growths together with the growth of the population. If in the 1990s for each new person in the canton there was needed 0.72 Ha of urban land, then it should be the same in the 2020s. It can still be more efficient. 14

15 Third Scenario: Compact Growth It is the most efficient scenario. In this scenario, each new person in the 2020s would consume 0.06 Ha of Urban Land. Considers that urban growth would still happen, but moderately. 15

16 Comparison between the three scenarios 16

17 4. Global Diagram (Schéma Macro Level) The proposal for a global diagram that can conduct future settlement growth for the canton of Saint Vith is represented through the diagram placed below. The following description of its elements will help to interpret it and understand the way it can structure the territory, while at the same time can keep the rural atmosphere and the adaptation to its wider context The green element The green element remains an important component that strengthens the idea of the rural milieu. It is composed of all the forest areas that together act as an ecological network that supports an integral landscape, together with the open spaces that shelter arrays of human settlements surrounded by agricultural land or grassland. The most powerful feature in this network is the Hautes Fagnes national park, that helps also as a division between the cities further north and the rural canton of Saint Vith The mobility element The mobility element structures the connections between the micro-region with the outer territories, particularly towards Belgium. The presence of the regional bus service through these transportation lines drawn in the diagram means that this dependence on the service is and will continue to be a fundamental spine for the needs of commuting within the canton and outside of it, as well The clusters The clusters are the elements where the settlements take place and develop. They are where the ordinary life happens. They function as part of a system that includes the relation between other clusters within the canton, but also other cities and towns outside of it. They are classified in four different types, as follows: The highest hierarchy that has only one cluster and it is commanded by the town of Saint Vith and its surroundings. It is the only place where an urban core exists. It includes also other residential nodes and the industrial areas of Saint Vith. A second level appears in Butgenbach, Amel and the western part of Burg-Reuland. They are arrays of nodes that, even though they remain to be rural, they have small cores of mixed activities. In this hierarchy a mutual support between nodes is aimed. A third level of clusters is predominantly rural, and somewhat dependent on its higher immediate level to get services for its inhabitants. It is aimed that in the future this dependency is less. The clusters in this level are Bullingen, east Reuland and Manderfeld, close to the German side. A last level of hierarchy is one in which one to three smalls hamlets are grouped together in order to get basic services. Nonetheless, they would depend more on other levels of clusters for efficiency reasons. Settlement growth at this level is unwanted, therefore, encapsulation with nature elements could be a strategy, since most of them are near the forests. 17

18 Moreover, all the clusters but the ones in the last level have a principal node, where the main services and facilities concentrate. Other nodes in the cluster are secondary. 18

19 5. Local Analysis and Development Proposal 5.1. Meso Level The next level of analysis is the cluster. In this case, as an example for this study, the Butgenbach cluster was explored. As the higher level of territory, this level is also structured but some elements that can even be reached at a walking or biking distance. These elements are: The nodes These elements are where the human settlements are. For the case taken, the nodes are Butgenbach, which commands the cluster, Elsenborn, Berg, Weywertz and Nidrum. The last one will be also zoomed in, following the micro analysis. It is important to mention that the TEC bus service line number 394 going from Eupen to Saint Vith town stops by the villages of Butgenbach and Elsenborn. The services are aimed to be shared between the nodes. This means that they are complimentary to each other. The connectivity network This element is composed of many types of connectors, including the public transportation component. As mentioned above, the bus lines goes through this territory and it uses the provincial road. Other minor roads are also part of the network. An important type of connector is that which has elements laid in the open country: the "ravels", the "lignes de desir", and other paths that are to be used by walk or by bike. Many of these soft, but important elements, are accompanied or crossed by natural elements such as water creeks, small or large forests, hedgerows of bushes and also a railroad. The cluster could be inscribed in a big circle of 3 Km of radius and the walking distance between closest villages is about 2 Km. 19

20 The natural elements The largest components of the natural network are a large forest in the northern part and a picturesque forest together with the lake of Butgenbach. This last element is shared also by the small village of Berg. As stated before, natural elements such as water creeks, small forests and hedgerows of bushes laid together in the country to accompany the mobility network and reinforce the rural atmosphere. It is important to mention that the group experienced a walk in the ravel, next to these mentioned elements in order to know the real experience The Micro Level Zooming in to the next level of analysis is the settlement level (or node level). But, yet in a deeper detail, an area within a circle of 500 meters diameter (the walking distance) was studied. The area is one of 6 nodes that were visited by the group in order to have a clearer idea of the current situation and to settle appropriately a realistic proposal to organize better the territory at the human scale. 20

21 This circle covers the small core of the village, represented with the church as a landmark, together with a small school, a small pub and a corner store (red area in the map). In the opposite side of the figure is the road that connects Nidrum with Elsenborn, passing by the Provincial Road. The map above shows, besides the plots and buildings provided by the cadaster database, an analysis through the 100x100 m2 grid that shows with graduated colors the density of the land measured in terms of squared meters of construction per hectare. The example shows that even though the selected green cell (red outline) looks similar in layout to the selected yellow cell (also red outline), the examination in detail reveals that the former has 5 buildings, 7 housing units and 830 m2 of building area, while the latter has 7 buildings, 11 housing units and m2 of building area. This demonstrate the potential that this particular part of the territory has to get transformed from a green cell to a yellow one and still display a rural atmosphere, as the picture below in the right shows (which was taken in a yellow area): still large open spaces, isolated buildings, but at the same time with a concentration of built area and not spread all over a single plot. 21

22 Some other figures help to characterize the selected area. The following maps and charts illustrate the composition of the study area regarding the specific land use, the number of floors built, the building layout type, the plot area and frontage, the built area in each plot and the number of buildings per plot and the building typology regarding its use. 22

23 The sample within the studied is composed of 190 plots. The graph that analyses the plot areas and frontages show that the pattern of plot sizes and proportion could be between 300 to 800 m2 for the area and a frontage of between 30 and 40 meters. A high number of plots did not have access to the streets, probably because they were registered like that in the cadaster for private management purposes. 23

24 5.3. Proposal in detail The following plans illustrate how in a street segment in Nidrum, a few dozens of meters away from the central church, is possible to densify the area with more buildings and extensions set discretely and in a concentrated way. The density could change from 800 m2 per hectare to 1500 m2 per hectare. The country elements in the views, such as other small buildings, the pastures, the orchards, the forests, and the sky can still be appreciated and the rural atmosphere still can be perceived. The plan in the left shows in black shapes the current buildings. The empty plots are colored in brown. On the right side, on the other hand, there is a proposal that consolidates the milieu with more buildings in red that are concentrated, in one case in tandem, in other cases hidden behind the front buildings, or as small extensions in yellow. This strategy is accompanied with small areas of forests or other elements from the rurality in the bottom of the plots, while at the same time giving plenty of open space and air. Not all the plots have to be filled in. In the example, the plots in the east remain empty, one of them has an equestrian use, which helps to reinforce the rurality. Furthermore, only very few new division of plots are proposed and no new roads have to be built. Likewise, the following photomontages illustrate what has been proposed above with the plans. 24

25 Current View of Nidrum Proposal for consolidation of Nidrum Finally, in order to complement the functionality of the whole system of human settlements, the group presents the following diagram that could work as a "Rule of Thumb" in the moment of providing the services for the different nodes, clusters and the whole canton. It is based on criteria of efficiency in the expenditure of resources, accessibility, but also would help to create a sense of community for the rural. 25

26 Chart adapted adapted to the St Vith Canton case from the book: "Towards an Urban Renaissance" (The Urban Task Force, 1999) 5.4. Comments about other nodes Butgenbach Besides the Nidrum case, the group visited other nodes to understand the differences and particularities that the different places can have. For instance, in the Butgenbach node there was a noticeable higher density than in Nidrum. Nonetheless, it still has the potential to get denser. In the left picture below it is important to notice that the houses are laid in an isolated way, so that people can still perceive through the lateral setbacks different planes of the rural landscape. On the other hand, on the picture of the right it is noticeable a misuse of the space as a parking lot, which can be reduced and let the space be used to shelter more dwellings. 26

27 Saint Vith Saint Vith is the only node that can be considered as urban. It portrays, as the picture on the left below shows, continuous urban profiles with adjacent houses that altogether support higher densities. Nonetheless, at the same time, and just a few dozens of meters away from the core of the town there are underused spaces such as the one depicted in the picture on the right below. In this space, if parking is still necessary, it has the potential to be developed together with multistory housing, quality open space and some sidewalk level retail. Reuland The first picture below shows the how in Reuland the canyon-like topography has led to a more compact development at first sight. Nonetheless, when exploring in detail, the group found that there were still some undeveloped plots, which can be appreciated in the second picture below. This means that still this settlement has a potential for compact consolidation. 27

28 Weweler The left picture below shows the accessibility challenge to reach Weweler, a hamlet that is located on a top of a hill southeast from Reuland, at a 2 Km walking distance. What could be done in this hamlet is to work on the quality of the buildings rather than to build new ones. This place, led by its beautiful church and cemetery are the crown from where to enjoy a wonderful view of the landscape located in the German border of the micro-region (right picture). 28

29 6. Conclusions & Recommendations The Germanophone Belgian milieu owns particular features that can be projected towards as follows: On one hand to be the border transitional space that relates 3 countries and their cultures and landscapes. On the other hand it can put in higher value its mostly rural character combining in a balanced manner a high living quality of its human settlements together with country economic dynamics and natural elements. To achieve the described balanced vision it must adopt a model that while preserving the rural image (open views to natural landscape) it can also shelter new inhabitants but in compact buildings development. Furthermore, to achieve such atmosphere, complimentary components must be enhanced, such as the lignes de desir, ravels ; as well as social service facilities (sports, cultural, education, health) at accessible, but prudent distances. A strong policy regarding agriculture and grassland fostering remains necessary, together with a strict normative against urban expansion and pro-consolidation, so that urbanizing must not be more attractive than country activities. Likewise, the forests and waterbodies protection policies must remain. 7. Bibliography Beckers, A. (2013). Contribution of land use changes to future flood damage along the river Meuse in the Walloon region. Natural Hazards and Earth System Sciences, European Environment Agency. (1996). European Environment Agency. Retrieved from European Environment Agency: Mustafa, A. M., Cools,, M., Saadi,, I., & Teller, J. (2015). Urban Development as a Continuum: A Multinomial Logistic Regression Approach. ResearchGate, Service Public de la Wallonie. (2016). Autoroutes et Routes de la Wallonie. Retrieved from Autoroutes et Routes de la Wallonie: Service Publique de la Wallonie. (2016). Service Publique de la Wallonie. Retrieved from Service Publique de la Wallonie: The Urban Task Force. (1999). Towards an Urban Renaissance. London: Queen's Printer and Controller of HMSO. 29