Scientific basis for developing key environmental criteria of FSC forest certification standard

Abstract

Developing certification criteria requires solid scientific knowledge. An extensive review of scientific literature was carried out by the author for WWF Finland. The aim of the study is to improve eight key environmental criteria of the Finnish FSC –standard in the revision process. Altogether 200 scientific articles and reports were reviewed and their main findings presented in a report that is published by WWF Finland in March 2018. The review was mainly based on Finnish and Swedish research articles and reports supported by some Norwegian and Estonian articles. The articles were selected by the author according to their usefulness for developing measurable criteria and indicators for the FSC –standard. Based on the results of the review conclusions and suggestions were made for developing current criteria more efficient for protecting biological diversity, soils and waters. The knowledge, conclusions and suggestions are used in the revision negotiations between environmental organizations and forest industries. Key findings are: Forest buffer zones 20-30 meters wide are ecologically efficient for protecting aquatic habitats, as well as riparian forest habitats in most cases. Also around protected spruce mires 20-30 meter wide are well justified for buffering microclimatical changes. Saving naturally dead trees in all forest operations is the most cost-effective way to increase the volume and diversity of dead wood in managed forests. Spared dead trees should be primarily over 20 cm thick. In the areas with high conservation values the target for the volume of dead wood should be over 20 m3/ha. This kind of areas should cover 10-30 % of forest landscapes. Minimum of 5-10 % of the stand volume should be left in final fellings as retention trees. retention trees should be at least 20 cm thick at breast height. Higher levels of retention ought to be used in areas of high conservation values. Several key biotope types were suggested to be added in the FSC criteria as they were currently lacking. It is ecologically well justified to retain 30 % of the volume of slash and stumps in energy wood harvesting. In forest fertilization 20-30 m wide buffer zones should be left along watercourses, and 50 m when the fertilizers are spread from air. The most significant water quality impacts of soil preparation are caused by maintenance ditching and ditch-mounding on peatlands and fine textured mineral soils. On high risk areas continuous cover forest management should be used. On controlled burning areas 10-20% of the stand volume should be left as retention trees to provide a longer continuity of fire scarred and dead trees. Keto-Tokoi, P. 2018. Science-based recommendations for developing environmental criteria of the Finnish FSC forest certification standard. Report of WWF Finland. Unpublished report in Finnish.