Analysis of drought stress in the forests of Orava region during period 2015-2021

The aim of this work was the analysis of the occurrence of drought, which was determined by the deficit of precipitation and the deficit of soil moisture in the time period 2015 till 2021 in the Orava region, in the comparison with the extent of damage caused by the drought and important biotic pests on the adult forests, which had been registered by the foresters of the Lesy SR, the state corporation. The Orava region was chosen because of the long-term spruce forests decline and the occurrence of more severe drought, which had been rare in the past there. The long-term soil water deficit can expressively weaken the forests, what was finally confirmed in our work. The biotic malign factors Ips typographus L., Pityogenes chalcographus L. and Armilaria sp. were chosen for their high multitudes and for their predisposition to continue in the process of the degradation of woods, as the secondary, respectively the tertiary malign factor beside the drought. The condition of forest vegetation has the long-term feedback to the bad availability of soil moisture, which depends on the specific species resistance to the drought stress. The ascertained results confirm the suitability of the chosen methodology for the drought monitoring, because its outputs are in good agreement with the reports of drought impacts by the end employers. The soil water deficit correlates with deficit of precipitation. It was registered, that the occurrence of important biotic pests in the dry periods is more frequent and the warnings and precautions are inevitable.