Fast recovery of Norway spruce trees after thinning from above on a drained peatland forest site

Part of:
12:30, Wednesday 29 Jun 2022 (1 hour 30 minutes)
Salle polyvalente (SH-4800)   Virtual session
This session is in the past.

Click below to enter the virtual room.

Enter virtual room

Are you a speaker or staff?

Access for speakers and staff

Continuous cover forestry (CCF) has been promoted as an environmentally sustainable option for drained peatlands. The CCF management has also been challenged due to potential lower tree growth compared to traditional even-aged management, especially with suppressed trees that are released during thinning.

Our objective was to quantify the time lag of stem growth response after CCF thinning with suppressed Norway spruce trees. We also tested if carbon uptake of these trees increases immediately after thinning.    

We used tree increment cores from suppressed Norway spruce trees to estimate the impact of thinning from above on the delay and quantity of diameter growth and photosynthesis. The study was conducted in Lettosuo experimental site, where part of the stand was thinned according to CCF principles, and the other part was left as a control. We used δ13C measurements to quantify how reduced between tree competition alters the photosynthetic rate and stomatal conductance ratio of sampled trees. Those sampled trees from the thinned area were then compared to those from the control area.

Our results show that there was an average delay of 2 years with a moderate increase in the diameter increment of the suppressed trees after thinning, while during years 3 and 4 after thinning, the increase in the diameter was much greater. In contrast to that delay, we found that the photosynthetic rate increased immediately after thinning, as shown by the instant 2.5‰ change in δ13C during the following summer. 


Natural Resources Institute Finland (Luke)
Principal Scientist


Session detail
Allows attendees to send short textual feedback to the organizer for a session. This is only sent to the organizer and not the speakers.
To respect data privacy rules, this option only displays profiles of attendees who have chosen to share their profile information publicly.