Marta Afonso
Student
School of Agronomy, University of Lisbon
Portugal

Biography
Marta Afonso is a Landscape Architect graduated from Instituto Superior de Agronomia, University of Lisbon. On her master degree she has developed a passion for landscape planning and Geographic Information Systems. This interest is strengthened by her skills in the technologic field, improved from her attendance in the degree in computer engineering at Instituto Superior Técnico. Within this context, her field work for master thesis explores land use policies using an approach that combines an Urban Growth Model and GIS. She is currently doing an internship in Biodesign, a Landscape Planning studio based in Lisbon, and her work is focussed mainly in coastline planning.

Abstract
Using the SLEUTH Cellular Automaton Based Model to Evaluate the Impacts of Multiple Land Use Policy Scenarios on Urban Growth Patterns in the Peninsula de Setubal Area

Co-Authors:
Pedro Arsenio, Reasercher and Assistant Teacher, Instituto Superior de Agronomia
Joao Rodrigues

The cellular automaton model SLEUTH was applied to a 1432.7 km2 area centered in Peni­nsula de Setubal to simulate the impacts of different land use policies based on an Ecological Network projected out to 2030. The study area was selected due to the profound changes of the urban sprawl that were felt for five decades and have been destroying the biophysical system and jeopardizing the existing natural resources. Therefore, the model was calibrated using an historic time series of 1940, 1963, 1990 and 2007 developed areas. Projections were made according to three different policy scenarios: Current Trends, Moderate Ecological Protection and Extreme Ecological Protection. Results were analyzed with software Fragstats 4.2 and showed that in all scenarios the urban growth occurs mainly at the periphery of existing urban centers. The Current Trends scenario generates the highest number of new urbanized cells and leads to substantial consumption of soil throughout the study area, with a simultaneous loss of natural resources. The Extreme Ecological Protection and Moderate Ecological Protection scenarios produced a more constrained growth with less natural resources consumption. These two scenarios encounter the aim of Regional Plan for the Lisbon Metro Area (PROT-AML) to adopt a more compact city model development in order to counter the extensive and fragmented model that has been followed in recent decades and that would remain if current growth trends continue. Despite the fact that both Extreme Ecological Protection and Moderate Ecological Protection scenarios meet the criteria of compact city, the scenario that best fits is the Extreme Ecological Protection, since it allows higher aggregation and cohesion of urban space along with greater protection of natural resources. This application of SLEUTH showed that the Ecological Network works as an instrument that is able to efficiently control the urban sprawl, preventing an abrupt increase in the average area of urban spaces. Also demonstrates that SLEUTH model can be a useful tool in landscape planning because it has a capacity to address a wide range of planning subjects and to promote a more informed decision making in the planning process among the stakeholders.