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Fire is a significant agent for the development of boreal and hemiboreal forests, altering soil and light conditions, affecting seedbanks, and removing seed trees. Burned areas should be managed with care, as inappropriate techniques prolong the regeneration period and reduce the diversity and resilience of stands to disturbances. To study the effects of fire and postfire management on the successional changes in regeneration abundance, species composition and tree height sample plots were established in sandy pine forests in northwestern Estonia on areas burned 2 or 22 years ago. Five types of sample plots were established: (i) areas without fire damage, (ii) burned uncleared areas, (iii) burned forest areas cleared after forest fire, (iv) burned uncleared areas with live trees, and (v) burned uncleared areas with dead trees. Three main tree species common to hemiboreal forests were analyzed: Betula spp., Pinus sylvestris L., and Populus tremula L. Results showed that clearing burned areas after wildfire significantly reduced the abundance of regeneration compared with burned uncleared areas but favored height growth of P. sylvestris in later development. To regenerate and maintain mixed stands after wildfire, retaining some residual trees can facilitate regeneration compared with complete clearing, although a dense stand with live trees or a large amount of deadwood can hinder regeneration.

The main tenets of forest health management are to simultaneously maintain productivity and all native species over time, which will in turn maintain ecosystem services provided by the forest. Natural disturbances oppose the stable flow of materials, while removals of timber short-circuit the flow of organic materials to the deadwood pool and reduce the average age of stands and trees across the landscape. It is likely that natural forests possess some level of redundancy with respect to the amount of deadwood and older trees and stands that are needed to maintain forest health, making it safe to remove timber products from the forest. Although this safe level of harvest is not exactly known, using practices such as close-to-nature forestry or best management practices with regard to structural features left after harvesting can ensure adequate residuals and help maintain forest resilience to disturbance. Furthermore, natural and human disturbances are not totally additive because, by chance, some stands are harvested before they are disturbed by fire or wind, making stand and tree-age distributions somewhat resilient to human disturbance. Harvesting stands and trees over a range of ages in the forest matrix of the landscape, thus minimizing truncation of stand and tree-age distributions due to harvest, combined with a system of reserved/reference forests to serve as a baseline for the effects of forest management, is probably the best way to create resilient forests and maintain adequate habitat for native species at all spatial extents and productivity over time.

We compared the changes in aboveground biomass and initial recovery of C pools and CO2 efflux following fire disturbances in Scots pine (Pinus sylvesteris L.) stands with different time since stand-replacing fire. The study areas are located in hemiboreal vegetation zone, in north-western Estonia, in Vihterpalu. Six areas where the last fire occurred in the year 1837, 1940, 1951, 1982, 1997, and 2008 were chosen for the study. Our results show that forest fire has a substantial effect on the C content in the top soil layer, but not in the mineral soil layers. Soil respiration showed a chronological response to the time since the forest fire and the values were lowest in the area where the fire was in the year 2008. The respiration values also followed seasonal pattern being highest in August and lowest in May and November. The CO2 effluxes were lowest on the newly burned area through the entire growing season. There was also a positive correlation between soil temperature and soil respiration values in our study areas.