Original scientific paper
https://doi.org/10.15177/seefor.16-14
The Role of Tree Mortality in Vitality Assessment of Sessile Oak Forests
Imre Berki
; University of West Hungary, Institute of Environmental and Earth Sciences, Bajcsy-Zsilinszky 4., H-9400 Sopron, Hungary
Ervin Rasztovits
; National Agricultural Research and Innovation Centre, Forest Research Institute, Várkerület 30/A, H-9600 Sárvár, Hungary
Norbert Móricz
; National Agricultural Research and Innovation Centre, Forest Research Institute, Várkerület 30/A, H-9600 Sárvár, Hungary
László Kolozs
; National Food Chain Safety Office, Keleti Károly 24., H-1024 Budapest, Hungary
Abstract
Background and Purpose: The drought-induced vitality loss of sessile oak (Quercus petraea (Matt.) Liebl.) has been continuously observed in Hungary for more than three decades. The decrease in stand density as a consequence of drought-induced mortality has not been taken into consideration in most of the monitoring methods.
Materials and Methods: Forest stands without any forest intervention during the last 30 years were selected. Quadrats were designated for the analysis in 18 sessile oak stands along a climatic transect in which foliage transparency and stand density were measured. Drought stress was defined by the water balance approach. By combining the foliage transparency and the relative stand density, a new cumulative assessment method of stand level vitality was introduced to get a more realistic picture about the effects of long-term drought (lasting for several decades) on the sessile oak forests in South-East Europe.
Results: The calculated health status (100% - vital; 0% - dead) of the sessile oak stands was between 70-90% in the moist South-West Hungary and below 50% close to its xeric limit. The individual tree-based vitality assessment method gave considerably higher values on 17 out of 18 sites.
Conclusions: Forest monitoring should also consider stand level-based tree mortality in oak forests while assessing health condition especially close to its xeric limit. The proposed new method provides a more realistic picture about the effects of climate change on sessile oak stands particularly for forest managers interested in changing in the wood stock of forests.
Keywords
Quercus petraea (Matt.) Liebl.; drought; mortality; stand density; forest monitoring
Hrčak ID:
170298
URI
Publication date:
9.12.2016.
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