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Forest regeneration within the treeline ecotone in the Giant Mountains under climate change
Cudlín, Ondřej ; Chumanová-Vávrová, Eva ; Edwards-Jonášová, Magda ; Heřman, Michal ; Štěpánek, Petr ; Cudlín, Pavel
Natural regeneration of mountain spruce forests began in the Giant Mountains 25 years ago after a reduction\nof severe and long-enduring air pollution. This process has been influenced by climatic change.\nThe aim of our contribution was to present background data for the potential elevational shift of spruce\nregeneration under conditions of climate change. These upslope shifts may also depend on constraints\nsuch as climate extremes, unfavourable soil conditions, absence of ectomycorrhizal symbionts, and lack of\nmicrosites suitable for seedlings. Since 2014, we have studied the main driving factors affecting Norway\nspruce regeneration, and in particular soil conditions, ectomycorrhizal symbionts, ground vegetation cover,\nand forest health, in six transects across the treeline ecotone located on a NW-to-NE transect through\nthe Giant Mountains. Microclimatic measurements showed that the mean difference in growing season\ntemperature between the montane spruce forests and forests at the treeline was −0.54°C. The model\nHADGEM2 predicted that in 20 years the temperature at the treeline will be similar to the current one at\nmontane elevations. The difference in prevailing soil types between the montane spruce forests and forests\nat the current treeline (i.e. podzol vs. ranker type) could be an important factor limiting success of the\nupslope spreading of spruce. Furthermore, areas covered by microsites favourable for natural spruce regeneration,\nespecially spruce litter patches, decaying wood, mosses, and Avenella flexuosa stands, were\nshown to decrease with increasing elevation. It is likely that spruce will move upslope in response to climate\nchange, but the process is likely to be slow or even blocked for some periods, especially by unfavourable\nsoil conditions and climatic extremes.
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Natural disturbances in central-european mountain spruce forests. A basis for forest restoration
Edwards-Jonášová, Magda ; Čermák, Martin
Risk of natural disturbances is a frequently discussed topic in the context of mountain spruce forests and global climate change. Recently, large-scale natural disturbances such as bark beetle outbreaks and windfalls have appeared relatively more frequently in Central-European mountain spruce (Picea abies L.) forests, which led to the enforcement of salvage logging even in some protected areas. Our study was performed as part of a long-term observation of recovery of spruce forests aff ected by bark beetle and windfall with and without interventions in two Central-European national parks, Šumava National Park in the Czech Republic and Tatra National Park in Slovakia. Th e results proved the ability of spruce forests to recover unassisted even from stand-replacing natural disturbances. Th eir biological legacies, which include standing and lying dead wood, are important for natural regeneration of tree species, and provide critical habitats for particular forest species. In comparison to natural disturbances, the artifi cial disturbances resulting from salvage logging destroyed a substantial part of the natural regeneration, which led to the need for artifi cial reforestation. Th us, the non-intervention strategy appears to be the best option for restoration of disturbed forests in the zone of mountain spruce forests. Based on our results, we propose that natural disturbances be considered as a basis for forest regeneration and restoration of their natural structure.
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Deposition ozone flux over a Norway spruce forest and correlation with
Zapletal, M. ; Cudlín, Pavel ; Chroust, P. ; Urban, Otmar ; Pokorný, Radek ; Edwards-Jonášová, Magda ; Czerný, Radek ; Janouš, Dalibor ; Taufarová, Klára ; Medlen, A. ; Večeřa, Zbyněk ; Mikuška, Pavel ; Skácel, F.
Measured and modelled results of ozone deposition and stomatal flux to a Norway spruce forest in locality Bílý Kříž in July and August 2008 were compared. Enhanced concentration of ozone decreased net ecosystem production, especially at higher temperatures and high intensity of global radiation.
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Natural regeneration of mountain spruce forests: 10 years after a bark-beetle outbreak
Jonášová, Magda
An extensive area of mountain spruce (Picea abies (L.) Karst.) forests in the Šumava National Park has been affected by a massive bark beetle (Ips typographus (L.)) outbreak since the middle of the 1990s. Parts of forests were left without interventions, while salvage logging was applied in other areas. The results indicated that a natural succession of mountain spruce forests after a bark beetle outbreak, if left without interventions, avoids a pioneer stage and direct recovery of the spruce forests is possible. Wind-dispersed pioneer species appeared temporarily in clear-cuts shortly after salvage logging, but their share in the whole regeneration was negligible after ten years. The height and age structure of spruce regeneration was reduced in clear-cuts. There was also a severe effect of salvage logging on ground layer vegetation compared to the bark-beetle outbreak itself.
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Central-European mountain spruce forests: regeneration of tree species after a bark beetle outbreak
Jonášová, Magda
Two different approaches were applied to mountain spruce (Picea abies) forests attacked by bark beetle in the Šumava National Park (Czech Republic): (1) a small portion of the stands was left without intervention, relying upon natural regeneration, and (2) traditional technical measures were adopted, in which attacked trees were felled and removed. The results confirmed that the original tree species of the mountain spruce forests regenerate well under dead canopy and the bark beetle outbreak could even be considered as a tool for the restoration of their natural character.
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