Ungulate browsing shapes climate change impacts on forest biodiversity in Hungary

Abstract

9 Abstract Climate change can result in a slow disappearance of forests dominated by less 10 drought-tolerant native European beech (Fagus sylvatica) and oak species (Quercus spp.) 11 and further area expansion of more drought-tolerant non-native black locust (Robinia 12 pseudoacacia) against those species in Hungary. We assumed that the shift in plant species 13 composition was modified by selective ungulate browsing. Thus, we investigated which 14 woody species are selected by browsing game. We have collected data on the species 15 composition of the understory and the browsing impact on it in five different Hungarian 16 even-aged forests between 2003 and 2005. Based on these investigations the non-native 17 Robinia pseudoacacia living under more favourable climatic conditions was generally 18 preferred (Jacobs' selectivity index: D = 0.04 ± 0.77), while the native Fagus sylvatica 19 and Quercus spp. (Q. petraea, Q. robur), both more vulnerable to increasing aridity, were 20 avoided (D =-0.37 ± 0.11; -0.79 ± 0.56; -0.9 ± 0.16; respectively) among target tree 21 species. However, economically less or not relevant species, e.g. elderberry (Sambucus 22 spp.), blackberry (Rubus spp.) or common dogwood (Cornus sanguinea) were the most 23 preferred species (D = 0.01 ± 0.71; -0.12 ± 0.58; -0.2 ± 0.78, respectively). Our 24 results imply that biodiversity conservation, i.e. maintaining or establishing a multi-species 25 understory layer, can be a good solution to reduce the additional negative game impact on 26 native target tree species suffering from drought. Due to preference for Robinia pseudo-27 acacia selective browsing can decelerate the penetration of this species into native forest 28 habitats. We have to consider the herbivorous pressure of ungulates and their feeding 29 preferences in planning our future multifunctional forests in the light of climate change 30 impacts.

Drivers of temporal changes in temperate forest plant diversity vary across spatial scales

“…Decreases in all three diversity measures of diversity were related to high game densities. Similar patterns were observed by Katona et al (2013) and Jenkins et al (2014), who attributed decreases in species richness at high browsing pressure to selective damage of plants preferred by game for feeding. Such selective feeding may result in increased cover of ferns, a pattern in accordance with our results.…”

“…Similar patterns were observed by Katona et al . () and Jenkins et al . (), who attributed decreases in species richness at high browsing pressure to selective damage of plants preferred by game for feeding.…”

How important is supplementary feed in the winter diet of red deer? a test in Hungary

“…Th e feeding program should take into consideration the natural dietary preferences and diet choice of the red deer about which much is known (M á trai and Kabai 1989, Gebert and Verheyden-Tixier 2001, Szemethy et al 2003. Finally, it is very important to evaluate the status of the entire forest area based on the availability and quality of food supply in the understory layer (Katona et al 2013). We emphasise that the use of feeding plots is only partly determined by the supplementary food itself, as the natural food supply off ered to red deer by other patches of the habitat should be much more important.…”

Forest biodiversity in a changing climate: which logic for conservation strategies?

“…How these species shifts are moderated and influenced by game populations and their browsing activities is the main research question of the contribution from Katona et al (2013). The authors analysed data of understory species composition and browsing impact from five different even-aged forest ecosystems in Hungary.…”