The correlation between the changes in climate, the intensity of spruce decline and the abundance of of spruce bark beetles in 'Golija' Nature Park

Abstract

The paper presents the results of the research on the correlation between changes in microclimate, the intensity of spruce decline and active abundance of its two economically most significant harmful insects-eight-toothed (Ips typographus) and six-toothed (Pityogenes chalcographus) spruce bark beetles (Coleoptera: Curculionidae) in Golija Nature Park whose pure and mixed conifer stands are dominated by spruce. The route method and ocular inspection were applied to study the presence and determine the intensity of spruce decline-both of individual trees and groups of trees in the management units of Dajićke planine, Kolješnica, Golija and Brusničke šume. Population dynamics of the two species of bark beetles and their active abundance were monitored by the method of trapping with barrier traps and the use of combined pheromone dispensers-PCIT Ecolure. Although the decline of individual conifer trees, primarily of spruce, had already been present in certain areas of these management units for several decades, it reached epidemic proportions due to extreme adverse climatic conditions in the period between 2011 and 2012 and culminated in 2015. A large number of physiologically weakened trees raised the population levels of secondary harmful insects and the number or the active abundance of the two investigated species of insects reached a peak in 2016. The inability to take appropriate and timely remedial measures in the areas under stricter protection regimes greatly contributed to this situation.

Mites Associated with the European Spruce Bark Beetle Ips typographus (Linnaeus, 1758) in Europe, with New Evidence for the Fauna of Serbia

“…Biotic and abiotic disturbances associated with climate change currently pose the greatest threat to coniferous forests in Europe [1][2][3][4]. In Serbia, a sharp decline in coniferous forests has been observed since 2012 [5][6][7][8][9][10]. The main reason for this decline was droughts that occurred during growing seasons and caused damage of 116,290 m 3 with a percentage of 89% dead spruces and fir [11].…”