ZLV Online

The Norway spruce decline in the northern part of Moravia and Silesia has increased in last years. After the drought year 2015 there was a strong need to define areas where calamitous damage on forests is primarily caused by drought. Immediate solution was applied by combining existing maps provided by the Czech Meteorological Institute mainly for agricultural crops. For the definition of drought risk in forest ecosystem we have used the water balance maps for the years of 2012–2014 to comply the long-term effects of drought to tree species in combination with 2015 maps of soil drought indexes where we have counted approximate length and severity of the period with soil water content lower than 30% of standard usable soil water capacity. The estimate is still rough, and application of new models based on forest water balance should be developed in the near future.