Alonso

Integrating urban agriculture to achieve more resilient city-regions. The case of central Spain

Nerea Morán ALONSO 1 – Marian SIMON-ROJO 1*± – Anaz Zazo MORATALLA 2

1 Surcos Urbanos, GIAU+s, Faculty of Architecture,Technical University of Madrid (ESP)
2 Universidad         Bio Bio and Surcos Urbanos (ESP)
Speaker
± Corresponding author: (e-mail address)


Introduction

The impact of urban sprawl in Spain during the last decades has been especially significant on periurban agrarian landscapes. They have been directly affected by the urbanization, and indirectly, as the appreciation in the value of land after new urban developments, they induced the abandonment of the agricultural activity. Since 2009, as a result of the severe economic crisis, building activity has slowed down radically. This convenient truce for the menaced periurban areas, combined together with an increasing interest in cities as key players in a transition towards a more sustainable model in which urban food plans are a critical issue, opens a window of opportunity for integrating periurban agrarian areas into wide strategies for resilient city-regions.

Spanish inner urban areas. Methodology of analysis

The I+D project PAEc-SP research analyzed the urban expansion of Spanish inner middle size cities (50.000-325.000 inhabitants) between 1990 and 2010. The sample included 29 cities. Those belonging to coastal provinces were not included in the study.

Urban structure, land use and morphological patterns were analyzed in order to identify different typologies. The cartographic source was the Corine Land Cover database The first level was used to calculate percentages of urban, agricultural and forest areas along the periurban landscapes; level 3 (44 cathegories) was used to identify land use classes. The space within a radius of 10, 15 or 20 km from the city center is analyzed, depending on the size of the population. In addition, ortophotos from PNOA (National Plan of Aerial Ortophotography), were consulted to check land uses.

 

Ecological capacity Ecological Network, natural node Vulnerable ecological network
60% Agrarian area potential agroecological network Residual agrarian area, vulnerable Urban area with areas of open spaces
15% Residual agrarian area Urban area with intersticial agrarian land Urban area
30% 60% Density of urbanization

Figure 1. Ecological capacity and urbanization intensity. Source: Matrix adopted from Bernetti & Bologna (2010)

 

To assess the possibilities of periurban agrarian land, para desempeñar funciones both as agricultural productive areas and as part of green infraestructure, a matrix adopted from Bernetti ¬ Bologna (2010) was used, in which two indicators are combined: ecological capacity and density of urbanized areas.

Apart from the compact city model, three different types of urban expansion were identified: monocentric with centrifugal/lineal sprawl along the main roads, monocentric with a scattered mosaic of urban uses, and polycentric agglomeration.

Results

Seven out of the 29 cities maintain a compact structure. In most cities, urban growth was based on a mix of the first and second types. The metropolitan area of Madrid followed a different pattern, adopting the form of a polycentric agglomeration, an urban continuum that has embedded several urban centers, leaving interstitial open areas.

Regarding urban uses located in the periurban area, in four of the 29 cities the occupation has been due exclusively to industrial uses, in eight cities is purely residential, while the remaining show a mix of residential, commercial, leisure and sport areas, industrial or technological hubs, airports and high-speed train stations, and other urban services and facilities.

In the periurban area, agrarian spaces are shaped in various forms: hyperfragmented areas because of infrastructures, isles surrounded by urbanization or by ring-roads, semi-continuous fringes, or a patchwork of small rural and urban uses.

By 2006 agricultural land occupied 60% of the peri-urban area of the cities analyzed. Eighty-three percent of the agricultural land that was lost, was transformed into artifi-cial-urban land, while the remaining 17% is now considered forest or semi-natural area. The pressure that was concentrated on agricultural land between 2000 and 2006 as three times higher in absolute numbers than that on forest and semi-natural land.

We assume that sparking a reappraisal of the role of agriculture is necessary to counterbalance the urban pressure. Therefore, the identification of different models of urban growth was accompanied by an analysis of the agrarian land and the territorial structure and their potential functions and benefits for the urban population.

The main conclusions of the research show that in spatial terms, the best option for a large part of Spanish inner cities is to develop a system of agrarian green belts or buffer zones, together with agrarian green wedges. On the contrary, the metropolitan region of Madrid should enhance a system of interstitial agrarian land and apply green wedges to connect them to the second metropolitan ring.

References

Bernetti, Iacopo; Bologna, Stefano (2010) Trasformazioni dell’uso del suolo e frammentazione della matrice agroambientale. In Magnaghi, Alberto; Fanfani, David (eds) Patto città campagna. Un progetto di bioregione urbana per la Toscana centrale. Firenze: Alinea Editrice. Pp 67-84
Simon Rojo, M., Moran Alonso, N., Zazo, A., & Rodríguez, R. (2013). Urbanismo y sistemas agrarios periurbanos/Urbanism and periurban agrarian ecosystems. Ed Mairea