Lambeets K.,Ghent University |
Breyne P.,Research Institute for Nature and Forest INBO |
Bonte D.,Ghent University
Biological Conservation | Year: 2010
Habitat patches along river systems are often highly isolated and characterised by a high degree of heterogeneity at different spatio-temporal scales. The connectivity between river bank arthropod populations directly adjoining the river channel is often greatly disturbed due to river regulation. While flight-active arthropods easily disperse upstream, less mobile species are expected to show predominant downstream dispersal unless specific upward movements are prevalent. In linear river ecosystems, downstream drift of organisms may therefore prevail with subsequently strong asymmetrical gene flow. We analysed patterns of genetic variation within and among nine spatially structured populations of the highly stenotopic riparian wolf spider (Lycosidae) Pardosa agricola (Thorell, 1856) using Amplified Fragment Length Polymorphism (AFLP) markers. No evidence was found for downstream accumulation of genetic diversity. The high genetic diversity is hypothesised to be the result of historical drift processes. Nearby populations on the same river shore were less genetically differentiated compared with populations further away and/or on the opposite shore. This indicates that short-distance dispersal still occurs on river banks during low water flow levels, but at the same time that the river channel constitutes a physical barrier for species exchange between opposite shores. The rehabilitation of the riparian corridor will increase the amount of suitable habitat, the functional connectivity during periods of low flow-discharges and eventually riparian spider population persistence. © 2009 Elsevier Ltd. All rights reserved.
van Herzele A.,Free University of Brussels |
van Herzele A.,Research Institute for Nature and Forest INBO |
de Vries S.,Wageningen University
Population and Environment | Year: 2012
This paper investigates the nature of the relationship between the greenness of the local environment and the health and well-being of its inhabitants by looking at a number of possible mediators within the same study: physical activity, perceived stress, ability to concentrate, social cohesion and neighbourhood satisfaction. Data were collected through a survey of residents in two neighbourhoods that differ objectively in green space provision, but which are largely similar in demographics, socio-economic factors, housing conditions and other environmental characteristics, apart from green space. Of the three dependent variables of interest: self-reported general health, bodily functioning and general well-being (happiness), it was self-reported happiness that differed significantly between the two neighbourhoods, with greater happiness in the greener neighbourhood. Amongst the possible mediators, people's satisfaction with their neighbourhood differed significantly: those living in the greener neighbourhood were more satisfied. Mediation analysis indicated that neighbourhood satisfaction fully mediates the relationship between neighbourhood greenness and happiness. Among the specific (environmental and social) neighbourhood qualities asked about, perception of neighbourhood greenness was found to be the most important predictor of neighbourhood satisfaction. Additional analysis showed that the view from the living room-green or not green-fully mediates the relationship between neighbourhood greenness and neighbourhood satisfaction. This study underscores the importance of nearby green space for people's overall well-being and suggests the need for green space to be evaluated in terms of visual proximity, that is, whether and how it is experienced from the street and the home. © 2011 Springer Science+Business Media, LLC.
Buizer M.,Wageningen University |
Van Herzele A.,Free University of Brussels |
Van Herzele A.,Research Institute for Nature and Forest INBO
Forest Policy and Economics | Year: 2012
In the past few decades governments in Western European countries have put increasing efforts into creating new green and forest areas in and around cities. At first sight, these centrally formulated plans seem to run counter to the current trend towards less central steering and more participation (and deliberation). However, closer scrutiny in two cases of green structure planning in the Netherlands and Flanders - Balij-Biesland forest and Park forest Ghent - reveals that we are facing a seemingly contradictory image of central steering on the one hand and openness to various actors and ideas on the other. This paper takes a closer look at this ambivalent situation using the two theoretical perspectives of deliberative governance and a discourse analysis. Although the green structure planning exercises did not intentionally have a deliberative character, we argue that such a perspective can and should be put on situations where new local coalitions challenge the centrally formulated plans, and try to start deliberations about their ideas In order to become more specific about the 'deliberative incompleteness' of the two Flemish and Dutch processes, a discourse-analytical focal point needs to be taken as well. Normatively, the paper first addresses the diversity of viewpoints and openness to preference shifts in the Dutch and the Flemish cases. It concludes that in the course of both processes, a high diversity of viewpoints surfaced, as well as a certain degree of openness to preference shifts. When the two processes are subjected to discourse analysis, it becomes evident however that the preference shifts occurring as a result of the input of a greater diversity of viewpoints did not bring about changes in some vital discursive practices that had been connected to the green structure planning and implementation processes. It was suggested, therefore, that combining the two theoretical perspectives gives a good insight into 'deliberative incompleteness' and highlights persistent institutional obstacles to come to more inclusive green structures in urbanized areas. © 2010 Elsevier B.V.
Keune H.,Research Institute for Nature and Forest INBO |
Keune H.,University of Antwerp
Environmental Health: A Global Access Science Source | Year: 2012
The magic word complexity has been buzzing around in science, policy and society for quite some time now. There seems to be a common feel for a new way of doing things, for overcoming the limits of tradition. From the combined perspective of critical complexity thinking and environment and health practice we want to contribute to the development of alternative routines that may help overcome the limitations of traditional environment and health science. On the one hand traditional environment and health science is too self-confident with respect to potential scientific insight in environment and health problems: complexity condemns us to limited and ambiguous knowledge and the need for simplification. A more modest attitude would be more realistic from that point of view. On the other hand from a problem solving perspective more boldness is required. Waiting for Godot (perfect undisputed knowledge) will not help us with respect to the challenges posed to society by environment and health problems. A sense of urgency is legitimate: the paralysis by traditional analysis should be resolved. Nevertheless this sense of urgency should not withhold us from investing in the problem solving quality of our endeavour; quality takes time, fastness from a quality perspective often leads us to a standstill. We propose the concept of critical complexification of environment and health practice that will enable the integration of relevant actors and factors in a pragmatic manner. We will illustrate this with practical examples and especially draw attention to the practical complexities involved, confronting us not only with fundamental questions, but also with fundamental challenges. © 2012 Keune; licensee BioMed Central Ltd.
Maes D.,Research Institute for Nature and Forest INBO |
Vanreusel W.,Natuurpunt |
Jacobs I.,Natuurpunt |
Berwaerts K.,Vlinderwerkgroep Natuurpunt |
Van Dyck H.,Catholic University of Louvain
Biological Conservation | Year: 2012
Red Lists are used to assess the extinction risk of species based on quantitative IUCN criteria. For the compilation of a new Red List of butterflies in Flanders (north Belgium), we collated ca 800,000 distribution records and applied the IUCN Red List criteria to this small region (ca 135,00km 2). We also explored the effect of spatial resolution on the outcome of the Red List assessment by alternatively using 1×1km 2 and 5×5km 2 grid cells for geographic range size and trend calculations. We determined conservation hot spots in Flanders based on the Red List status of the species composition in each grid cell. The new Red List classified 20 butterflies (out of 68 resident species) as Regionally Extinct, six as Critically Endangered, five as Endangered, seven as Vulnerable and seven as Near Threatened. The remaining 23 species were classified as Least Concern. Using coarse instead of fine grain grid cells would have classified ten species in a lower Red List category. Compared with the previous Red List, nine species were classified in a lower and 12 in a higher threat category. In total, 218 1×1km 2 grid cells were considered as (very) high butterfly conservation priority sites. The application of the new IUCN criteria in a small region such as Flanders resulted in a Red List that offered challenging opportunities for the conservation of butterflies in particular and biodiversity in general. © 2011 Elsevier Ltd.
Blicharska M.,Swedish University of Agricultural Sciences |
Van Herzele A.,Research Institute for Nature and Forest INBO
Forest Policy and Economics | Year: 2015
This paper addresses the long-standing debate over the conservation and management of the Białowieza Forest in North-eastern Poland, frequently referred to as the last, large, close-to-natural, temperate, lowland forest in Europe. With the present research we aim to document how particular conceptualisations of "forest" shaped the debate and the fate of the Białowieza Forest. Based on our reconstruction and analysis of argumentation, three dominant discourses could be distinguished, each offering different concepts of forest and people-forest relationships: 1. 'managerial' - with foresters presented as stewards of the forest, actively managing it for sustainable outcomes; 2. 'livelihood' - considering the forest as local heritage and underlining its role in fulfilling people's needs; and 3. 'primaeval' - highlighting the forest's intrinsic value and natural processes, being an international concern. The three discourses remained remarkably stable over the past two decades, but their status of institutionalisation evolved, which in turn influenced their hegemony and power. Importantly, our study demonstrates the active role of parties involved in the debate as they used particular concepts (their own, those of others or new ones) for strategic purposes. We conclude that both the achieved hegemony of a discourse and the particular ways by which its concepts are mobilised by actors may play a decisive role in shaping debate and its policy outcomes. We suggest that future research should focus more on the role of actors in strategically using particular forest-related concepts in concrete situations and to what effects. © 2015 Elsevier B.V.
van Herzele A.,Research Institute for Nature and Forest INBO |
Aarts N.,Wageningen University
Policy Sciences | Year: 2013
Social research that informs the implementation of natural resource policies is frequently driven by the logic of the policy system itself. A prevailing concern with achieving policy outcomes can lead, however, to lack of attention to equally important aspects, for example the challenges the policy instruments present to those they are targeting and the consequences this might have for government-citizen relationships. To help guide research into these issues we have developed a situational-interactional approach to interpretive policy analysis that seeks to examine the processes involved when people collectively make sense of government instruments. The theoretical basis is provided to a large extent by Luhmann's theory of self-referential social systems. In addition, we operationalise the concepts of interactional framing and resemiotisation to capture the active work of the citizens in sense-making processes. We then apply our situational-interactional analysis to small-scale forest ownership in Flanders. Analysis of data from focus groups with forest owners reveals how interactions build on each other in the co-development of particular strategies to cope with government intervention. Finally, we discuss two future directions for research. First, the forest owners find themselves in an inescapable relationship with the government, and feel their autonomy is threatened. Government intervention, therefore, will almost necessarily lead to resistance. Second, forest groups enhance compatibility between the government system and the forest owners, but rather than narrowing the gap between the two worlds they tend to emphasise it. © 2012 Springer Science+Business Media, LLC.
Munoz-Mas R.,Polytechnic University of Valencia |
Martinez-Capel F.,Polytechnic University of Valencia |
Garofano-Gomez V.,Polytechnic University of Valencia |
Mouton A.M.,Research Institute for Nature and Forest INBO
Environmental Modelling and Software | Year: 2014
Probabilistic Neural Networks (PNN) have been tested for the first time in microhabitat suitability modelling for adult brown trout (Salmo trutta L.). The impact of data prevalence on PNN was studied. The PNN were evaluated in an independent river and the applicability of PNN to assess the environmental flow was analysed. Prevalence did not affect significantly the results. However PNN presented some limitations regarding the output range. Our results agreed previous studies because trout preferred deep microhabitats with medium-to-coarse substrate whereas velocity showed a wider suitable range. The 0.5 prevalence PNN showed similar classificatory capability than the 0.06 prevalence counterpart and the outputs covered the whole feasible range (from 0 to 1), but the 0.06 prevalence PNN showed higher generalisation because it performed better in the evaluation and it allowed a better modulation of the environmental flow. PNN has demonstrated to be a tool to be into consideration. © 2014 Elsevier Ltd.
Cools N.,Research Institute for Nature and Forest INBO |
Vesterdal L.,Copenhagen University |
De Vos B.,Research Institute for Nature and Forest INBO |
Vanguelova E.,Japan Forestry and Forest Products Research Institute |
Hansen K.,IVL Swedish Environmental Reserach Institute Ltd
Forest Ecology and Management | Year: 2014
The C:N ratio is considered as an indicator of nitrate leaching in response to high atmospheric nitrogen (N) deposition. However, the C:N ratio is influenced by a multitude of other site-related factors. This study aimed to unravel the factors determining C:N ratios of forest floor, mineral soil and peat top soils in more than 4000 plots of the ICP Forests large-scale monitoring network. The first objective was to quantify forest floor, mineral and peat soil C:N ratios across European forests. Secondly we determined the main factors explaining this C:N ratio using a boosted regression tree analysis (BRT), including fifteen site and environmental variables.Ninety-five percent of the C:N ratios were between 16 and 44 in the forest floor, between 13 and 44 in the peat topsoil and between 10 and 32 in the mineral topsoil. Within the aerated forest floor and the mineral soil, the C:N ratios decreased with depth, while in the hydromorphic forest floor and the peats no clear trend with depth was observed.Tree species was clearly the most important explanatory variable for the C:N ratio in both forest floors and topsoils, while it was soil type in the deeper mineral soil layers. The lowest C:N ratios both in the forest floor and the top mineral soil were found in black locust (Robinia pseudoacacia L.) and black alder (Alnus glutinosa L.) stands, both N fixing tree species. While in the forest floor the highest C:N ratios were found in evergreen species like pine, cork oak (Quercus suber L.) and eucalyptus, the pine species and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) showed the highest C:N ratios in the mineral soil. The second most important explanatory variable in the forest floor and mineral topsoil was the biogeographical zoning (ecoregion). In the peat topsoil and in the deeper mineral soil layers it was the humus type. Deposition and climatic variables were of minor importance at the European scale.Further analysis for eight main forest tree species individually, showed that the influence of environmental variables on C:N ratios was tree species dependent. For Aleppo pine (Pinus halepensis Miller) and holm oak (Quercus ilex L.), both with a typical Mediterranean distribution, the relationship between N and S deposition and C:N ratio appeared to be positive. This study suggests that applying C:N ratios as a general indicator of the N status in forests at the European level, without explicitly accounting for tree species, is too simplistic and may result in misleading conclusions. © 2013 Elsevier B.V.
Van Herzele A.,Research Institute for Nature and Forest INBO |
van Woerkum C.,Wageningen University
Landscape and Urban Planning | Year: 2011
Whether in reports, face-to-face or online environments, maps are the most familiar tools for communication about landscape and urban plans. Apart from professional advantages to communicating with maps, there is also a widespread belief that citizens can participate more effectively if information is presented visually rather than in words. While we acknowledge that maps are proven and powerful tools for facilitating social interaction, we seek to illuminate how the tools themselves set the communicative conditions for that interaction. We use a mainstream example - the green structure for Ghent - to illustrate how the map participates in and shapes public debate. We suggest that assessing how maps " work" is a prerequisite for understanding the dynamics of a map-based interactional process and its consequences, which can help in turn to critically reflect on and, where appropriate, change the conditions of communication. © 2011 Elsevier B.V.