Effect of the size of retention tree groups on biodiversity in forest regeneration (RETREE)

• Objective and description of the project
  • Aims of the project
  • Collaboration
  • Study area
  • Thesis under work
• Funding
• RETREE researchers

Objective and description of the project

New management practices intended to ensure ecological sustainability of forestry have been developed during the past few years, although knowledge of their efficiency is limited. Consequently, science-based knowledge to support the development of such methods is urgently needed. The aim of this RETREE project is to contribute to the development of such harvesting methods that take biodiversity into consideration by optimising the location and size of retention tree groups according to biodiversity aspects. According to the FIBRE documentation assessment of forestry practices, development of new ones and research on special biotopes in forests to enhance ecologically sustainable forestry are key themes of the programme.

The specific aims of the project are:

1. to assess the effect of the size and other features of the retained tree groups in moist, paludified forest patches on their potential to maintain the original fauna and flora when surroundings are logged,
2. to establish where the critical thresholds are regarding population viability and size of tree groups,
3. to assess how various taxonomic groups survive within retained tree groups,
4. to develop models and guidelines regarding size, shape and positioning of retained tree groups.

The research is done in collaboration between the Univ. of Helsinki and the Finnish Forest Research Institute. The team consists of prof. Jari Niemelä (project leader, student supervisor, Univ. Helsinki), MSc Ilkka Vanha-Majamaa (co-supervisor, FFRI), PhD student Katja Matveinen (Univ. Helsinki) and PhD student Marja-Leena Heinilehto (Univ. Helsinki & FFRI).

The study area is in Heinävesi, eastern Finland, in forests owned by Stora-Enso where 12 moist patches of 0.2-0.6 ha each in mature forest were chosen in the spring of 1998 (plus 8 other patches to study their windfirmness). During 1998 pre-treatment sampling was done, the surroundings of the patches were cut in March 1999, and assessment of biotic changes began in the spring of 1999. Field work will be conducted during 1998-2001 (one year before treatments and three years after).

Two PhD thesis will be produced:
PhD student K. Matveinen (Effects of size of retention-tree patches on invertebrates) examines how the retained tree groups sustain populations of land snails, ground dwelling spiders and ground beetles. PhD student M-L. Heinilehto (Changes in vegetation following retention tree felling in mature spruce forest) aims at finding out the adequate size of a retained tree group to maintain plant species, and how regeneration of trees is affected by the size of the retained tree group.

The research is directly applicable in the development of tools and methodologies for the sustainable management of forest ecosystems by indicating how size of the retained tree-groups affects their potential to maintain original fauna and flora. Furthermore, the study will indicate the minimum size of viable retention tree patches. As recommended in FIBRE mid-term evaluation, the study area can serve as a useful demonstration site.

Funding

The research is funded by the Finnish biodiversity research programme (FIBRE)

RETREE researchers

Team leader:

Professor Jari Niemelä
Department of Ecology and Systematics,
P.O. Box 17, FIN-00014 University of Helsinki,
e-mail: jari.niemela@helsinki.fi,
tel: +358-9-191 28791, fax: +358-9-191 28701

Researchers funded by FIRBE:

MSc Katja Matveinen, PhD student
Department of Ecology and Systematics,
P.O. Box 17, FIN-00014 University of Helsinki,
e-mail: katja.matveinen@helsinki.fi,
tel: +358-9-1917376, fax: +358-9-19128701

MSc Marja-Leena Heinilehto, PhD student
Finnish Forest Research Institute,
P.O. Box 18, FIN-01301 Vantaa
e-mail: marja-leena.heinilehto@metla.fi,
tel: +358-9-857051, fax: +358-9-8572575

Other researchers:

MSc Ilkka Vanha-Majamaa, researcher
Finnish Forest Research Institute,
P.O. Box 18, FIN-01301 Vantaa
e-mail: ilkka.vanha-majamaa@metla.fi,
tel: +358-9-85705557, fax: +358-9-8572575