Estimating the Impacts of Urban Expansion on Landscape Ecology: Forestland Perspective in the Greater Seoul Metropolitan Area

Abstract

Being able to predict the potential impacts of urban growth on the environment is a critical requirement for both urban developers and policymakers. The Korean national government recently announced a long-term urban plan, called the “Metropolitan Plan for the Greater Seoul Area 2020.” The fundamentals of the plan can be summarized as an urban development strategy that leads toward multinucleated urban centers with an easing of the greenbelt designations (area designated for preservation around a town or a city where development is strictly restricted by law). The objectives of this study are threefold: (1) to formulate urban development scenarios on the basis of the Metropolitan Plan for the Greater Seoul Area 2020, (2) to construct models to predict the future urban growth pattern in the greater Seoul metropolitan area, and (3) to analyze forest structural changes from the perspective of landscape ecology. This study first formulates four different urban development scenarios to provide a broader array of policy alternatives. On the basis of the respective scenarios formulated, this study attempts to predict the future urban growth by integrating a system dynamics (SD) model and a multilayer perceptrons (MLP) model. Furthermore, this study attempts to calculate the forest mean patch size and area-weighted mean patch size, and uses the gravity-based metrics, connectivity between patch centroids (CCE) and connectivity between circular patches (CCI), to assess the structural changes of forests that would occur under each respective scenario. The system dynamic model developed in this study successfully predicted the future urban growth area by incorporating not only economic elements but also political elements simulated under multiple scenarios. On the other hand, the spatial-allocation model successfully predicted that active large-scale urban development is likely to take place largely in the southeastern part of the greater Seoul metropolitan area under all four scenarios by the year 2020. This study concludes with a recommendation of which the easing of the greenbelt designation will inevitably cause adverse impacts on forest structure. In addition, this study suggests that effective multilateral policy alternatives can be discovered by formulating a variety of scenarios.