1.1. Problem Statement
The value of nature, the variety of functions and services it delivers for society, and hence the essential contribution to human living conditions, are widely acknowledged. However, translating this premise into practice lags far behind. New initiatives in land use planning, urban development, and environmental management are striving increasingly to guarantee more optimal and sustainable spatial and environmental conditions that meet the requirements of species and habitats. However, the current use of land and natural resources still has tremendous negative consequences for nature and biodiversity [
1]. As a result, most of the ecosystems in Europe are still degrading and do not deliver the optimal quality and quantity of basic services [
2]. For decades, at national and international levels, targets are set and strategies are launched to improve this situation. The protected ecological networks by the European Birds Directive (Council Directive 79/409/EEC) and European Habitats Directive (Council Directive 92/43/EEC), the integration of nature preservation goals into different policy domains, and the promotion of multifunctional land use, are typical elaborated strategies in this respect. In intensively used and densely populated regions in particular, much is expected from such approaches.
The evolution in spatial and nature policy in Flanders (a northern part of Belgium) exemplifies the typical challenges that urbanized regions are facing when trying to implement the agreed strategies. The spatial context of Flanders is characterized by a highly fragmented land use. Up until now, 32.5% of the Flemish territory is covered by dispersed built-up areas, including housing (and gardens), commercial and industrial areas, sport and recreation facilities, infrastructure [
3,
4]. The urban sprawl in Flanders is spawned out of a closely knitted network of historical villages and ribbon development, along a widely dispersed infrastructure network of roads, highways, railways and canals. Together with a very intensive agriculture, this urbanization resulted in a small-scaled spatial landscape mosaic, in which semi-natural sites are limited to small bits and pieces surrounded by intensively used land (
Figure 1).
Belgium and especially its northern part, Flanders, is, together with Luxemburg, confronted with the highest fragmentation pressure in Europe. In 2011, the European Environment Agency (EEA) calculated landscape fragmentation of European countries [
6]. The study shows that the western and central parts of Europe are the most fragmented regions with the Benelux countries as outliers. In Belgium, the Netherlands, and the North of France there are no areas of low fragmentation left. Additionally, large parts of Germany, Denmark, Poland, and the Czech Republic are indicated as highly fragmented. Those highly fragmented regions are mostly found along major transportation corridors and near large urban areas. Conversely, the lowest levels of fragmentation are associated with mountain ranges or remoteness and are found in the Alps, Scandinavia, eastern European countries, Mediterranean countries (except Portugal), Ireland, and Scotland [
6].
The ecological consequences of this radical spatial fragmentation are obvious [
7]. The ever more shrinking habitats are exposed to increasing edge effects, a growing lack of internal environmental heterogeneity, decreasing population sizes, a higher risk of extinction, and a lower chance of colonization, which makes them highly vulnerable and less sustainable in the long run. Thus, nature conservation in general focuses on preserving larger natural areas, regarding the ecological value of small natural areas as of minor importance. However, evidence is growing that this appreciation does not hold in general. With appropriate management and spatial configuration these small habitat patches can represent a significant biodiversity [
8], and can deliver a wide range of ecosystem services [
9], despite high pressures from, for instance, recreation or transportation.
The potential of small habitat patches to support biodiversity and to deliver ecosystem services, adds to their importance to increase sustainability and improve living conditions in intensively used and densely populated regions. Long before it was called ‘green infrastructure’ (GI), policies and instruments were developed to preserve and improve the ecological value of these remaining small semi-natural habitats. For decades, integrating these habitats in a coherent network of protected sites was the guiding principle. Attempts to establish ecological networks were made in several countries [
10]. Networks of small landscape elements in the wider countryside, adequately managed and guaranteed of appropriate environmental conditions, were thought to be effective for the ecosystem services they provide. Being a key concept of ecologists and conservation biologists, in the beginning, the notion of ecological networks and its reframing into the more technical ‘green infrastructure’, was quickly adopted by spatial and environmental planners [
11]. Since the European Commission launched the Green Infrastructure Strategy [
12], attention and importance further increased and European countries and regions engaged to realize effective GI networks.
Additionally, in Flanders, strengthening and completing the GI became one of the key objectives, not only for agencies, administrations, or organizations dealing with nature conservation, but also for spatial planning in general. In the current ‘strategic vision’ of the Spatial Policy Plan of Flanders [
13], clear objectives are formulated in this respect. It is stated that, to achieve a resilient and coherent open space, a so-called dense green-blue network must be implemented. The multi-functionality of the region’s open space and its green-blue network is a prerequisite. These goals and requirements regarding agriculture, nature, forest, and water must be taken into account and its composition, structure, design, and management have to support the objectives set for climate adaptation and mitigation, energy production and use, recreation, and public health.
To ensure a successful implementation of these green-blue networks, it is wise to learn from former attempts. In the past, several policy departments and interest groups have addressed GI. In 1991, the minister in charge of the Department for Environment and Nature launched the ‘Green Main Structure for Flanders’ (‘Groene Hoofdstructuur’ in Dutch) [
14]. However, due to a lack of political support, and because of the strong opposition of interest groups, the plan was withdrawn before any concrete realization was started [
15]. However, the idea of an ecological network was not abandoned. Detailed discussions and negotiations were conducted between different sectors and their legal bodies on the administrative level of the Council for Environmental and Nature Policy of Flanders. When this resulted in objectives and clear targets for a regional ecological network, an agreement was reached in 1997 to finally announce a new ‘Flemish Ecological Network’. GI were addressed in both the new Flemish Decree on Nature Conservation and the Flemish Decree on Physical Planning and its ‘Spatial Structure Plan’ (=a form of strategic planning). The ambition was to designate 125,000 ha as proper ‘Flemish Ecological Network’ (‘VEN’) (= 9.3% of Flanders) and 150,000 ha (or 80,000 ha in the revised version of 2011) of ‘Nature Integration Areas’ (‘IVON’) (=11.2% resp. 6% of Flanders) [
16,
17]. ‘VEN’ areas are considered as the backbone of the ‘natural structure’ in Flanders where nature prevails. In IVON areas, the goal is to provide additional opportunities for biodiversity. However, other functions such as agriculture, recreation, forestry, housing, etc. may not be jeopardized.
This designation was aimed to be done by 2003 according to the nature conservation decree, or by 2007 according to the physical planning procedure. After more than 20 years, and far beyond the deadlines, in 2020 74% of VEN and only 4% (or 7% for the revised version of 2011) of IVON has been designated [
18]. The latter is illustrative of the difficulties in working towards the integration of objectives and multifunctional land use. The prevailing policy of the sectors that shape and manage the countryside is still predominantly based on a planning policy that merely allocates mono-functional land use zones. This outdated type of planning often results in a ‘fight for hectares’, whenever new zoning plans are drafted.
It is obvious that regarding the main objective of green-blue infrastructure, i.e., to implement a coherent and functional ecological network, both policy programs failed. The constraints met are various [
19,
20].
Social constraints relate to:
the different perceptions of the impact of GI on management decisions and the use and value of private land,
the contrasting interests of nature conservationists, farmers, hunters, anglers or foresters and the mutual frictions this brings about;
the regulation of (land) use in designated areas; i.e., the issue of exclusive or joint use of designated land and the uncertainties this creates;
the lack of a clear and effective communication strategy, especially between members and officials of the regional government on the one hand and local stakeholders or the general public on the other, which results in the failure of a fruitful participation strategy.
Political and organizational constraints relate to:
the weak coordination capacity of different policy domains and departments, as well as the bad tuning of procedures and timing of different policy levels;
the lack of political agreement between political parties involved in the allocation of the ecological network.
Economic constraints relate to:
the indistinctness about the consequences of designation for economic activities and the required compensation if any;
the uncertainty about acquisition and management costs of GI and the availability of guaranteed funds.
Resource constraints relate to:
the incomplete knowledge about the nature targets of GI, the management practices necessary to reach these goals, and the consequences this has for formulating any alternative arrangements that may facilitate joint land use of designated land.
1.2. Looking for a New Approach towards Integration of Objectives: The Gobelin Project
The Flemish Environment Department, of which spatial planning is a part, wanted to consider an alternative approach to realize GI, being aware of the failures of the past. Rather than issuing another comprehensive blueprint plan, it was chosen to realize GI in conjunction with existing (re)development projects and work towards the integration of different objectives relating to GI and multifunctional land use. To explore the possibilities and opportunities of this approach, the ‘Gobelin-project’ was started. The project was commissioned by the Flemish Environment Department and conducted by the Institute for Nature and Forest Research (INBO) and the University of Antwerp (UA) from 2017 to 2019.
The poor developments regarding the ecological network in Flanders were clearly related to a defective top-down planning approach from merely one single perspective, namely the ecological view, combined with diverging discourses and objectives of different policy domains [
19]. With a top-down planning approach, we mean a large-scale and government-led approach on a higher planning level for a whole region. This top-down planning started from set objectives at the regional level (Flanders) that hardly took local demands and potentials into account. It was a unidirectional implementation and decision-making process with only few possibilities to allow adapting to local conditions. To overcome the failures of the past we chose instead to work bottom up. That means we envision a small-scale and local-led approach together with local administrations and organizations. This bottom-up approach starts from locally defined objectives and conditions which are interpreted gradually in an interactive and collaborative process and designed to meet the overall goals that are adopted at a higher level. This is in line with the conclusions of Bogaert [
19] who argues that, in order to make nature policy more successful, far better coordination between policy fields, and above all coherent linkages between the various aspects of the implementation process (discourses, actors, rules, resources) are prerequisites. The same conditions apply to the successful implementation of GI.
In this paper we concentrate on the first phases of the bottom-up approach. Sharing a common understanding of the issue at stake is the first thing that needs to be done. Therefore, we study how GI, with its ambiguous definition, can be adopted as a boundary concept in collaborative planning. We explore through participatory action research (1) how a variety of local stakeholders engage and interpret GI depending on different local contexts to find a common language, and related to the search for common goals, and (2) how different objectives and interpretations regarding GI can contribute to a design process with stakeholders and how the design process then stimulates the debate towards consensus. These research questions are particularly relevant for GI policy implementation in highly fragmented and intensively used areas. Areas where multiple demands for ecosystem service provision of GI on the one hand, and land use pressure that negatively impacts GI performance on the other, increase the need to fully take into account the local context and to engage local stakeholders in the implementation process.