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The front-wave velocity of African swine fever (ASF) virus spread is depicted through a retrospective spatial and temporal analyses of wild boar outbreaks from Jan. 2014 to Jan. 2022 in Estonia, Latvia, Lithuania and Eastern Poland-regions responsible for more than 50% of all wild boar cases in the EU. The study uses empirical semivariograms in a universal kriging model to assess spatial autocorrelation in notification dates and identifies a discernable large-scale spatial trend. The critical parameter of ASF front-wave velocity was identified (Mean = 66.33 km/month, SD = 163.24) in the whole study area, and explored the variations across countries, wild boar habitat suitability, seasons, and the study period. Statistical differences in front-wave velocity values among countries and temporal clusters are explored, shedding light on potential factors influencing ASF transmission dynamics. The implications of these findings for surveillance and control strategies are discussed.

There is an increasing interest in restoring degraded forests, which occupy half of the forest areas. Among the forms of restoration, passive restoration, which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management, is gaining attention. Natural dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions, composition and abundance of species, and the successional character of these species. Here, we study the natural dynamics of a mixed forest located in central Spain, which maintained an open forest structure, due to intensive use, until grazing and cutting were banned in the 1960s. The most frequent woody species in this forest are Fagus sylvatica, Quercus petraea, Quercus pyrenaica, Ilex aquifolium, Sorbus aucuparia, Sorbus aria and Prunus avium, with contrasting shade and drought tolerance. These species are common in temperate European deciduous forest and are found here near their southern distribution limit, except for Q. pyrenaica. In order to analyze forest dynamics and composition, three inventories were carried out in 1994, 2005 and 2015. Our results show that, despite the Mediterranean influence, the natural dynamics of this forest has been mainly determined by different levels of shade tolerance. After the abandonment of grazing and cutting, Q. pyrenaica expanded rapidly due to its lower shade tolerance, whereas after canopy closure and forest densification, shade-tolerant species gained ground, particularly F. sylvatica, despite its lower drought and late-frost tolerance. If the current dynamics continue, F. sylvatica will overtake the rest of the species, which will be relegated to sites with shallow soils and steep slopes. Simultaneously, all the multi-centennial beech trees, which are undergoing a rapid mortality and decline process, will disappear.

Aim of study: We aimed at identifying differences in the response to water shortage between Eucalyptus globulus clones. Area of study: Field trials were established in SW Spain. Material and methods: Potted plants from six clones were grown in a greenhouse for 35 days under two watering regimes. Two clones were F0 genotypes and the other four were F1 (hybrid) genotypes, including one inbred clone. Differences in stomatal conductance, hydraulic traits, growth and specific leaf area (SLA) were analyzed. Main results: Water shortage decreased SLA, growth in height and leaf area and leaf-specific hydraulic conductivity (KLmax). We measured the highest growth in F1 genotypes and the lowest in the clone in which SLA was lowest. The inbred clone showed the highest growth reduction under water shortage. There was substantial hysteresis between leaf water potential (Y) and native embolism, most probably a result of combined cavitation and refilling. High losses of hydraulic conductance were compatible with high stomatal conductances. Maximum values of stomatal conductance decreased with the soil water content estimated from predawn Y and were lowest in the inbred clone, showing less plasticity and a diminished ability to cope with high temperatures, which could explain its poor development under field conditions. Research highlights: Soil water content and predawn Y appeared as critical factors controlling stomata closure, while stomatal conductance and SLA could be useful to predict differences in growth and survival from early trials.

Biodiversity is essential for the functioning of ecosystems and the provision of services. In recent years, the role of plantations in mitigating climate change through carbon sequestration has been highlighted. In the Mediterranean area, high-density poplar plantations in short-rotation with resprouting management (SRC) have been established for biomass purposes on mostly irrigated agricultural land, coexisting with rainfed and irrigated agricultural crops. This study aims to assess the contribution of these plantations to this type of agroforest ecosystem in terms of biodiversity. For this purpose, both flora and fauna diversity were evaluated both within and outside of the plantation. Additionally, the accumulated carbon in the biomass, as well as in the accompanying vegetation within the plantation, was assessed. Different indices were used to evaluate both the intrinsic diversity of the forest plantation and the degree of substitution and complementarity between the different communities of the landscape. Our findings reveal distinct biodiversity patterns in the land-use scenarios sampled. Specifically, we observed significantly higher flora-species richness in SRC plantations than in the adjacent agricultural land, whereas fauna richness showed a similar but slightly higher level in the forested area. A moderate level of complementarity between land uses was found for insects and mammals (around 45 %), contrasting with high complementarity for birds (87 %) and flora (90 %). This suggests substantial turnover and replacement among these ecological environments. Our results indicate that a second rotation (4 year) plantation could accumulate a total of 61.6 Mg C ha-1, and even though adventitious flora represents <2 % of the total carbon accumulated, its importance in providing ecosystem services is considerable. Hence, these findings evidence the fact that SRC poplar plantations can enhance biodiversity in Mediterranean agroforest ecosystems and actively contri

The sensitivity of tree growth to climate is conditioned by several variables, often intermingled, such as the origin of the forest (natural vs. artificial), tree age, tree size and tree-to-tree competition. The effect of these variables is usually inferred from average growth series obtained at the stand level, thus ignoring the differences at the individual tree level and their drivers. Our objective is to disentangle the effects of stand origin, age, size, competition and social status on the sensitivity of tree growth to climate, including the effects of extreme climatic events, such as droughts, on resistance and resilience, and also to show the advantages of using a tree-level approach. To this end, we compared four stands of Pinus sylvestris with contrasting characteristics: young afforested, young of natural origin, old afforested and old of natural origin. We analyzed differences in growth sensitivity to climate at both stand and tree levels to compare both approaches. Our results show the great complexity of the relationships of the variables considered with the sensitivity of growth to climate. All these variables are important and with strong interactions between them, which makes their effects not unidirectional and strongly dependent on the site conditions. While the stand approach hides these interactions, the tree-level approach makes it possible to analyze them in detail. In general, the sensitivity of growth to climate increases with age, diameter, afforested origin, decreasing competition and higher social status; growth resistance increases with age, decreasing diameter, afforested origin, decreasing competition and higher social status; and growth resilience increases with age, diameter, natural origin, decreasing competition and higher social status. We show the usefulness of the analysis of data at individual tree level, which, combined with the joint analysis at stand level, allows us to obtain more accurate and detailed information.

Aim of study: We aimed at identifying differences in the response to water shortage between Eucalyptus globulus clones. Area of study: Field trials were established in SW Spain. Material and methods: Potted plants from six clones were grown in a greenhouse for 35 days under two watering regimes. Two clones were F0 genotypes and the other four were F1 (hybrid) genotypes, including one inbred clone. Differences in stomatal conductance, hydraulic traits, growth and specific leaf area (SLA) were analyzed. Main results: Water shortage decreased SLA, growth in height and leaf area and leaf-specific hydraulic conductivity (KLmax). We measured the highest growth in F1 genotypes and the lowest in the clone in which SLA was lowest. The inbred clone showed the highest growth reduction under water shortage. There was substantial hysteresis between leaf water potential (Y) and native embolism, most probably a result of combined cavitation and refilling. High losses of hydraulic conductance were compatible with high stomatal conductances. Maximum values of stomatal conductance decreased with the soil water content estimated from predawn Y and were lowest in the inbred clone, showing less plasticity and a diminished ability to cope with high temperatures, which could explain its poor development under field conditions. Research highlights: Soil water content and predawn Y appeared as critical factors controlling stomata closure, while stomatal conductance and SLA could be useful to predict differences in growth and survival from early trials.

Key message: Abies alba Mill.–Pinus uncinata Ramond. ecotone dynamics are examined along both altitudinal and protection level gradients by combining field inventories and Landsat data. An upward expansion of A. alba to the subalpine belt is observed in the last decades as a result of stand maturation after logging cessation. Context: High-mountain forests constitute sensitive locations to monitor the impacts of global change on tree-species composition and ecotone dynamics. In this study, we focus on the Spanish Pyrenees where silver fir (Abies alba Mill.) coexists with mountain pine (Pinus uncinata Ramond.) forming montane-subalpine ecotones. Aims: The main goal of this study is to assess the spatiotemporal dynamics of the silver fir–mountain pine ecotone and its underlying driving factors. Methods: We reconstructed the spatial distribution and dynamics of the species by combining remote sensing imagery and field plot data from 1989 to 2015, employing support vector machine techniques for image classification. Using variance analysis and mixed effects models, we then analyzed the evolution of basal area and replacement index, a measure of relative change in species composition, over time and altitude range. Additionally, we explored their relationship with site factors and protection level (National Park vs. protection buffer zone). Results: Silver fir has expanded its distribution in both the National Park and the protection buffer zone, whereas mountain pine has remained stable. Both species exhibit increased basal area associated with stand maturation and a higher level of protection. The replacement index indicates a rise in silver fir in the understory on North-facing slopes, attributed to stand densification. These findings are particularly noticeable in the area with the highest level of protection. Conclusion: The cessation of traditional land uses has led to ongoing stand densification, promoting succession and favoring the increased abundance of silver f

Process-based models and empirical modelling techniques are frequently used to (i) explore the sensitivity of tree growth to environmental variables, and (ii) predict the future growth of trees and forest stands under climate change scenarios. However, modelling approaches substantially influence predictions of the sensitivity of trees to environmental factors. Here, we used tree-ring width (TRW) data from 1630 beech trees from a network of 70 plots established across European mountains to build empirical predictive growth models using various modelling approaches. In addition, we used 3-PG and Biome-BGCMuSo process-based models to compare growth predictions with derived empirical models. Results revealed similar prediction errors (RMSE) across models ranging between 3.71 and 7.54 cm2 of basal area increment (BAI). The models explained most of the variability in BAI ranging from 54 % to 87 %. Selected explanatory variables (despite being statistically highly significant) and the pattern of the growth sensitivity differed between models substantially. We identified only five factors with the same effect and the same sensitivity pattern in all empirical models: tree DBH, competition index, elevation, Gini index of DBH, and soil silt content. However, the sensitivity to most of the climate variables was low and inconsistent among the empirical models. Both empirical and process-based models suggest that beech in European mountains will, on average, likely experience better growth conditions under both 4.5 and 8.5 RCP scenarios. The process-based models indicated that beech may grow better across European mountains by 1.05 to 1.4 times in warmer conditions. The empirical models identified several drivers of tree growth that are not included in the current process-based models (e.g., different nutrients) but may have a substantial effect on final results, particularly if they are limiting factors. Hence, future development of process-based models may build upon our findi

Se presenta un análisis de la afección por muérdago (Viscum album subsp. austriacum) en los principales hospedadores de las masas de pinares españolas (P. halepensis, P. nigra, P. pinaster y P. sylvestris) durante el periodo 2005 ¿ 2020, así como su tendencia bajo los efectos del cambio global. Se comprueba un aumento del daño a lo largo del periodo de estudio y una expansión ascendente en altitud. Se pone en relieve la importancia del cambio climático y mantenimiento de las redes de seguimiento de daños.