Criteria for the location of urban forests in densely populated and scarsely wooded areas

Abstract

Several policy and scientific documents emphasize the importance of the realization of new urban forests in densely populated and scarsely wooded areas. This paper aims at the development of a methodology to select the most suitable locations for the establishment of new large urban forests, taking into account the highest chances for success. The most suitable and feasible locations are selected by means of a multicriteria analysis. In this respect three phases of the multicriteria analysis can be distinguished: 1. The excluding phase: leading, by means of excluding criteria, to the fixation of a number of locations which are potentially suitable to afforestation; they are called potential locations. 2. The classifying phase: testing the potential locations to their suitability; this phase aims at the selection of a limited number of (theoretically) most suitable locations. It is based on the following groups of criteria: - criteria related to the potential recreational quality; - structure strengthening criteria; - criteria related to the potential ecological quality. 3. The feasibility phase: finally the most suitable locations are tested on their feasibility; leading, via an analysis of possible conflicts with other area claims, to the selection of the most feasible location(s). Because of the strong pressure on the land use in the densely populated areas, this fase is very important to optimize the realization chances of the afforestation. The three main criteria are: - the acceptability for the agricultural sector; - the acceptability for the nature and landscape values; - the acceptability for the urban functions. As a result of the three fases of the multicriteria analysis the most suitable and feasible locations are selected. In the classification phase as well as in the feasibility phase the different locations are divided into classes, according to the scores reached by the different criteria in their totality or each separatedly. The criteria and also the weights attributed to those criteria must correspond to the wanted profile of the planned forest, meaning they have to enclose spatial elements as well as functional and ecological elements. The feasibility phase can be completed with an analysis of the opportunity criteria, i.e. criteria which are mainly related to the short term realization of the project, e.g. rest lands and fallow lands or lands used by farmers without direct succession. The necessity to contact all involved actors in order to be successful is strongly stressed.