14 research outputs found

    Microclimatic buffering by logging residues and forest edges reduces clear-cutting impacts on forest bryophytes

    No full text
    Question: The practice of extracting logging residues after clear-cutting for bioenergy purposes is spreading. Logging residues constitute a shelter in clear-cut areas and therefore concerns have been expressed that their removal could make the ground and its vegetation more exposed to extreme micro¬climatic conditions. We asked whether logging residues and forest edges can protect ground-dwelling forest bryophytes from fatal microclimate events following clear-cutting. Location: Boreal forests of central Sweden. Methods: Using transplants of eight forest floor bryophyte species we experimentally analysed the sheltering effect (less solar radiation and less wind) of logging residues and forest edges in seven clear-cut areas. Transplants were placed in two contrasting positions in each area; near a north-facing forest edge and in the centre of the clear-cut area. In each position, half of the transplants were covered by a layer of spruce branches and the other half was left uncovered. We estimated proportion of apparently living shoots (apparent vitality) and measured radial growth of transplants during one growing season. Results: Position in the clear-cut area, but not cover of spruce branches, clearly influenced radial growth. Vitality scores were higher among transplants covered with branches and the lowest apparent vitality was observed in uncovered transplants in the middle of clear-cut areas. The change in area of apparently liv¬ing shoots during the course of the experiment (growth minus mortality) was unaffected by branch cover close to the edge but positively affected in the centre of the clear-cut area. In general, the effect of branch cover on bryophytes was higher in the centre of clear-cut areas. Here, climatic measurements showed that branch cover buffers during periods of extreme microclimates. Conclusions: Extraction of logging residues after clear-felling may reduce the survival of some ground-dwelling forest organisms. The additional sheltering provided by branches was unimportant close to forest edges. We suggest smaller clear-cut areas, green-tree retention and other ways to make logged areas shadier and less windy to mitigate the reduced shelter caused by harvest of logging residues

    Rationalising the policy mess? Ex ante policy assessment and the utilisation of knowledge in the policy process

    No full text
    Procedures for the ex ante assessment of public policies are currently in vogue across the OECD. Their design is typically informed by a rational-instrumental model of problem solving, which assumes that knowledge is collected, evaluated, and then translated straightforwardly into ‘better policies’. But this model has been little affected by more than three decades of academic research which has demonstrated that the reality of everyday policy making is far messier. In this paper we analyse whether the uptake of ex ante assessment of policies is nonetheless capable of creating opportunities for policy deliberation and learning informed by new assessment knowledge. Drawing on an analysis of policy assessment procedures in three countries and the European Union, we find that there are several ways in which assessment knowledge is used in the policy process. Moreover, we argue that policy learning occurs despite, rather than because of, the instrumental design of new assessment procedures, which tends to act as a barrier to open deliberation and knowledge utilisation
    corecore