African swine fever (ASF) has caused the swine industry of the Russian Federation substantial economic losses over the last 7 years, and the disease spread from there to a number of neighbouring countries. Wild boar has been involved in the spread of the disease both at local and at transboundary levels. Understanding ASF dynamics in wild boars is prerequisite to preventing the spread and to designing and applying effective surveillance and control plans. The reproductive ratio (R ) is an epidemiological indicator commonly used to quantify the extent of disease spread. Here, it was estimated in nine spatio-temporal clusters of ASF in wild boar cases in the Russian Federation (2007-2013). Clusters were defined by exploring the maximum distance of association of ASF cases using K Ripley analysis and spatio-temporal scan statistics. A maximum spatial association of 133 km in wild boar cases was identified which is within de the conventional radius of surveillance zone (100-150 km). The mean range value of R = 1.58 (1.13-3.77) was lower compared to values previously estimated for ASF transmission within farms but similar to early estimates between farm (R = 2-3), in domestic pigs using notification data in the Russian Federation. Results obtained provide quantitative knowledge on the epidemiology of ASF in wild boars in the Russian Federation. They identify the ASF transmission rate value in affected natural wild populations, for the first time, which could provide basis for modelling ASF transmission and suggest that current surveillance radius should be reviewed to make surveillance in wild nature more targeted and effective.

No abstract

20Forest dieback is one of the most widespread responses to global-change drivers such as

No abstract

No abstract

The aim of the study was to investigate dynamics and pattern of natural regeneration and the influence of seedbed and light on germination and initial seedling survival of Scots pine (Pinus sylvestris L.) during three growing seasons. Four 5-m 2 plots in a natural Scots pine forest in central Spain were randomly established at the beginning of the regeneration process. Germination and seedling survival were recorded in 100 regeneration sampling subplots (0.25 m 2 ) per plot, while seedbed type and the relative light intensity reaching the forest floor was characterised in 1-m 2 subplots. The spatial correlations between survival, light conditions and organic matter depth were analysed through crossvariograms. Germination and survival were highly variable both within and between plots (ranging from 0 to 89%) and affected by high summer temperatures (33-35°C) in 2003. The spatial pattern characterisation of survival by Ripley's K function showed a dominant cluster distribution. Occurrence tended to be clumped when abundance was greater than 15 seedlings, whereas for lower densities, seedlings were randomly distributed. Seedlings and herbs occupied the same sites where environmental conditions were appropriate for them to live. Spatial association occurred frequently for light and organic matter depth. Results suggested that the Scots pine seedlings in our study in central Spain preferred moderate light conditions (Global Site Factor <0.40). Thus, if this forest is to be naturally regenerated with Scots pine, the shelterwood system (whereby some mother trees are left to provide shelter for at least 5 years), along with mechanical disturbance of the seedbeds, would promote seed germination, as long as a seed source is present. However, regeneration success is affected by year-to-year conditions.

-Coppices are currently at a turning point: traditional uses have been abandoned and silviculture must be redefined according to new uses. Thinning to improve the development of trees is often the silvicultural treatment chosen. This paper attempts to assess the changes in forest structural diversity induced by different thinning regimes applied in coppice stands of Quercus pyrenaica and Quercus faginea. Structural diversity is analysed through spatial pattern, crown dimensions, vertical and horizontal differentiation and foliage height diversity. Moderate and heavy thinning have similar effects on stand structure, but the effects of light thinning are quite different for both species. The spatial pattern shows a greater regularity as the intensity of the thinning regime increases. The response of Q. pyrenaica to thinning is noticeable both in tree height and crown diameter, whilst in the case of Q. faginea, trees reacted to thinning by developing epicormic sprouts on the stem from the base of the crown. Vertical differentiation shows opposite trends in both species: increasing the intensity of thinning leads to an increase in vertical differentiation with Q. pyrenaica, but to a greater homogenisation shortly after thinning with Q. faginea. A neighbourhood analysis using Gadow's differentiation index is able to provide useful information on the changes in microstructure, while foliage height diversity index can be used to describe complex changes in the vertical structure of the stand. coppice / Quercus pyrenaica / Quercus faginea / structural diversity / thinning Résumé -L'effet des éclaircies sur la diversité structurale des taillis. Aujourd'hui, les taillis se trouvent à une phase de changement : on a renoncé à leur usage traditionnel, et alors la sylviculture est obligée de les redéfinir selon les nouveaux usage qu'on propose. Le recours aux éclaircies pour améliorer le croissance des arbres est le traitement de préférence. Ce travail a pour but l'identification des changements qui se sont produits dans la diversité structurale du peuplement, et qui ont été induits par l'application des divers types d'éclaircies sur les taillis de Quercus pyrenaica y Quercus faginea. La diversité structurale est étudiée avec l'analyse du modèle de répartition des tiges, de la taille des cimes, de la différenciation tant horizontale que verticale et des variations de hauteur du feuillage. Les éclaircies moyennes et fortes ont à peu près le même effet sur la structure du peuplement, mais l'effet des éclaircies plus légères est bien différent dans les deux espèces. Le modèle spatial montre une plus grande régularité au fur et à mesure que l'intensité de l'éclaircie augmente. La réponse de Quercus pyrenaica à l'éclaircie est bien évidente tant en ce qui concerne la croissance en hauteur que le diamètre de la cime. Mais pour Quercus faginea, les arbres vont réagir d'une autre façon, avec l'émission de bourgeons adventifs dès la partie inférieure de la couronne. La différenciation verticale va montrer deux tendances diffé...

No abstract