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The aim of this study was to assess the effects of bark stripping caused by sika deer (Cervus nippon [Temminck]) on the production and structure of young Norway spruce (Picea abies L. Karst) forest stands (41–43 years). Production parameters, structure, diversity, and the dynamics of radial growth in selected forest stands in relation to climatic conditions were evaluated. Similar to other production parameters, stand volumes showed lower values on research plots heavily damaged by bark stripping (290 m3 ha−1) compared to stands with lower tree stem damages (441 m3 ha−1). A significant decrease in stem volume was recorded for trees with stem circumference damage higher than 1/3 of the stem circumference. In most cases, the trees were damaged between the ages of 10–23 years, specifically the radial growth was significantly lowered in this period. The diameter increment of damaged trees dropped to 64% of the healthy counterparts in this period. Bark stripping damages reached up to 93% of the stem circumference with a mean damage of 31%. Stem rot was found on 62% of damaged trees. In our study area, with respect to the terms of climatic conditions, precipitation had a higher effect on radial growth of the Norway spruce compared to temperature. The main limiting climatic factor of tree growth was the lack of precipitation within a growing season, particularly in June of the current year.

For the monitoring of wild boar interactions with conspecific carcasses, seven wild boar carcasses were placed in different sites in the Czech Republic during winter season. Data were collected by camera traps. In total, 732 visits were recorded of wild boars at the carcass sites. Direct contact with the carcass was detected in 81% of the records. Cannibalism was observed in 9.8% of all recorded visits. The first direct contact was observed on average 30 days after the carcass had been placed in its respective site. Cannibalism was observed on average after 70 days. The effect of sex-age class on direct contact was not proven in our study. The presented findings show that cannibalism in wild boar can play a substantial role in the ASF epidemic.These results highlighted the importance of the removal of infected carcasses from the habitat, which is crucial for African swine fever eradication. K E Y W O R D S African swine fever, camera-trapping, cannibalism, wild boar behaviour S U PP O RTI N G I N FO R M ATI O N Additional supporting information may be found online in the Supporting Information section. How to cite this article: Cukor J, Linda R, Václavek P, Mahlerová K, Šatrán P, Havránek F. Confirmed cannibalism in wild boar and its possible role in African swine fever transmission. Transbound Emerg Dis.

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Sycamore maple (Acer pseudoplatanus L.) is a fast-growing tree species that produces economically attractive timber, provides ecological services and has high site adaptability, but it is only a minor component of European forests. This paper describes production, structure and diversity of sycamore-dominated forest stands that originated by succession on former agricultural lands in the Orlické hory Mts., the Czech Republic. The partial objectives were to determine impact of climatic factors on the radial growth of sycamore maple and evaluate the effect of game on natural regeneration. The number of sycamore seeds on the ground was on average 9-34 seeds m -2 and seedling mortality reached on average 89% caused by damage of hare and drought. Density of natural regeneration ranged from 1,532 to 4,244 recruits ha -1 , but growth dynamic was strongly influenced by ungulate browsing (69%) with the largest losses in sycamore (96%). Analyses of climatic effects showed a significantly close relationship with growth of sycamore in submontane areas, being especially sensitive to extremely dry and cold winters or very high summer temperatures. Radial growth was more significantly influenced by monthly temperatures compared to precipitation, but increasing sum of annual precipitation was main positive driver factor of diameter increment. Radial growth had the strongest relationship with weather conditions in July and October of previous year and March of the current year. Stand volume ranged from 378 to 545 m 3 ha -1 at age around 75 years, while sycamore accounted for 32-82%. The horizontal structure of the tree layer was mostly random to aggregated; resembling the clumped spatial pattern of natural regeneration. Besides their wood production, these stands fulfil many ecosystem functions that are associated with high ecological stability, high structural differentiation and medium to high species diversity.

Soil organic carbon (SOC) is a great component of the global carbon cycle and plays significant role in terms of climatic changes and agricultural land-use. An important management concern is the extent of SOC stocks sequestration when farmland is converted to forest stands. We have reviewed the literature about changes in SOC stock in relation to altitude and stand age and sought differences between former agricultural land and origin forest stands. Accumulation of SOC was monitored in 17 examples (41 samples) in 9 locations across the all Czech Republic with focus on the main tree species Norway spruce (Picea abies [L.] Karst.). Results showed a significant increase of SOC stock in an afforested farmland with increasing stand age. Another factor was the altitude. With increasing altitude, the carbon stock in our model gradually decreased. From the data analyzed comparing forest stand and former agricultural land, similar carbon sequestration was documented for both variants with higher SOC for forest stands. However, other conditions affecting SOC stock should be taken into consideration, especially silvicultural management, topography, disturbances, soil properties and cultivation. The general tendencies of SOC changes at the investigated sites are comparable to those in other studies across the Europe.

The paper deals with development of the natural regeneration of even-aged spruce-beech forests during their transformation to uneven-aged stands with diversified structure at the Jedlový důl area in the Protected Landscape Area Jizerské hory Mts., Czech Republic. Shelterwood management system and free felling policy based on selection principles has been applied there since 1979 with the support of admixed tree species of the natural species composition, especially silver fir (Abies alba Mill.). The research was focuses on structure and development of natural regeneration with the emphasis on ungulate damage and interaction with tree layer from 1979 to 2015. In the course of 36 years, the regeneration structure was diversified towards the close-to-nature tree species composition, spatial and age structure. The number of regeneration recruits increased in average from 941 to 41,669 ind ha -1. During this period share of European beech (Fagus sylvatica L.) significantly (p < 0.01) increased (by 53.6%), while the share of Norway spruce (Picea abies [L.] Karst.) decreased (by 51.5%), such as damage caused by ungulate (by 61.4%) with the highest loses on sycamore maple (Acer pseudoplatanus L.), rowan (Sorbus aucuparia L.) and silver fir. Moreover, the parent trees had a significant negative influence on natural regeneration at smaller spacing (within a 1 -5 m radius from the stem). Both, regeneration potential and effective role of the tree layer during the forest transformation has been confirmed as important prerequisites for ongoing forest transformation.

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