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• Primary production was estimated by using indices (EVI and NDWI) derived by MODIS. • We perform an ex-ante and ex-post analysis of a fire disturbance in a wetland. • EVI and NDWI time series show a similar trend before and after the fire. • After the fire EVI and NDWI are positive correlated. • There is no correlation between indices and climatic data (temperature and precipitation) Fire disturbance is an intrinsic component of the Mediterranean biome playing an important role in ecosystem dynamics and processes. However, frequent and severe anthropogenic wildfires can be detrimental to natural ecosystems, particularly in small natural protected areas, where they may hamper the flow of ecosystem services (ES). While post-fire dynamics of individual ES are heavily context-dependent, the primary productivity of the ecosystem can be regarded as a generic driver of several provisioning and regulating ES, as it represents the amount of energy available to plants for storage, growth, and reproduction, which drives future ecosystem structure and functions. The aim of this study was to evaluate the effect of anthropogenic wildfire on the primary productivity of a rare wetland ecosystem in the Natura 2000 site "Torre Guaceto" in Southern Europe. Productivity was estimated by calculating a 15-year time series of vegetation indices (EVI and NDWI) from remotely sensed MODIS imagery. Our results in terms of PP trends may be relevant to assess the change in ecosystems services provided by wetlands. Interactions between wildfire, ecosystem productivity and climate were then analyzed. During the selected period, climate did not play a significant effect on primary productivity, which was mainly driven by post-fire vegetation recovery. Findings of the present study demonstrate that the wildfire affecting the Natural Protected Area of Torre Guaceto in summer 2007 had a major effect on primary productivity, inducing the regeneration of Phragmites australis and the replacement of old individuals by structurally and functionally better ones. [ABSTRACT FROM AUTHOR]

Masting is the highly variable and synchronous production of seeds by plants. Masting can have cascading effects on plant population dynamics and forest properties such as tree growth, carbon stocks, regeneration, nutrient cycling, or future species composition. However, masting has often been missing from forest models. Those few that simulate masting have done so using relatively simple empirical rules, and lack an implementation of process-based mechanisms that control such events. Here we review more than 200 published papers on mechanistic formulations of masting, and summarize how the main processes involved in masting and their related patterns can be incorporated in forest models at different degrees of complexity. Our review showed that, of all proximate causes of masting, resource acquisition, storage and allocation were the processes studied most often. Hormonal and genetic regulation of bud formation, floral induction, and anthesis were less frequently addressed. We outline the building blocks of a general process-based model of masting that can be used to improve the oversimplified functions in different types of forest models, and to implement them where missing. A complete implementation of masting in forest models should include functions for resource allocation and depletion, and for pollination, as regulated by both forest structure and weather in the years prior to seed production. When models operate at spatio-temporal scales mismatched with the main masting processes, or if calibration data are not available, simulation can be based on parameterizing masting patterns (variability, synchrony, or frequency). Also, observed masting patterns have the potential to be used as “reality checks” for more process-based forest models wishing to accurately reproduce masting as an emergent phenomenon. [ABSTRACT FROM AUTHOR]

Interest in coppices is growing due to the need to replace fossil fuels with renewable energy sources. In Italy, beech covers one million hectares, half of which originated by coppicing. This study tested which factors drive the presence and growth of beech resprouts, with a focus on fertility, cutting intensity, age, and size at time of coppicing. We analyzed 509 stools in 24 stands coppiced between 1 and 26 years before sampling. We fitted Generalized Linear Mixed Models of the probability of sprouting and height of the tallest resprout for each stool as a function of elevation, slope, aspect, bedrock, precipitation, temperature, age at coppicing, time since coppicing, residual shoot density, the sum, average and coefficient of variation of the diameter of cut shoots, and type of stool treatment. Of all harvested stools, 249 (49%) had sprouted with an average of 7.6 resprouts per stool. Height of the tallest resprout on each stool ranged from 3 to 800 cm, mainly as a function of time since coppicing. Resprout mortality was on average 1.4% per plot. Sprouting decreased with decreasing site fertility, increasing precipitation, and increasing size of cut stems. Leaving one or more shoots on the stool after felling produced a high proportion of sprouting stools (82%). Although based on a limited sample, our quantitative analysis of the driving factors of sprouting in beech can be used to support silvicultural decisions in over-mature beech coppices, and to optimize trade-offs between ecosystem services such as biomass production, biodiversity, and hydro-geologic protection. [ABSTRACT FROM AUTHOR]

Mountain forests provide important ecosystem services, such as protection against natural hazards, carbon sequestration, and plant and animal biodiversity. Natural disturbances occurring in forests can alter the provision of ecosystem services to local and offsite communities, but their influence on multiple service tradeoffs has rarely been analyzed. Our aim is to analyze the effect of avalanche frequency on the provision of ecosystem services in a mountain forest in the Italian Alps. We sampled tree and understory vegetation, soil carbon, and intensity of the browsing damage at 10 plots at each of the following observation sites: (1) an active avalanche track (“recent disturbance”), (2) an area last disturbed in 1959 by avalanches (“old disturbance”), occupied now by a dense aspen forest, and (3) the regularly managed spruce–fir stand (“control”). We computed metrics of plant diversity (Shannon and evenness indices), aboveground and belowground carbon stocks, and a browsing index on regeneration and shrubs as a proxy for ungulate habitat. Finally, we assessed the ability of forests in each site to mitigate rockfall hazard. In our study, higher avalanche frequency was associated with lower carbon stock, higher species diversity, and lower protection against rockfall. Of all species found in the avalanche track, 54% were exclusive to that site. After 50 years, the post-disturbance stand provided a very high protection effect against rockfall, but was temporarily unsuitable for wild ungulate habitat, due to the high tree density and lack of open areas. Species richness and diversity were lower in older than in more recently disturbed sites, and not significantly different than the control stand. The control stand fulfilled the requirements for minimal protection against rockfall, but may lose its effectiveness in the near future due to senescence or disturbance-related mortality of canopy trees. Elucidating the tradeoffs between ecosystem services and disturbance frequency will support managers in planning management actions (e.g., avalanche protection measures), and assess tradeoffs between the need to mitigate risks in the most vulnerable areas and the opportunity to improve the provision of ecosystem services where some disturbance can be allowed to occur. [ABSTRACT FROM AUTHOR]

Abstract: Regeneration of non fire-adapted conifers following crown fires on the European Alps is often delayed or unsuccessful. Fire may limit establishment by eliminating seed trees, altering soil properties, or modifying microsite and soil conditions via disturbance legacies. However, the effect of soil legacies on post-fire establishment has rarely been discussed. We analyzed the abundance of Scots pine regeneration in a 257ha wildfire in an inner-alpine forest. Our aims were (1) to model fire intensity at the soil surface and topsoil heating along a gradient of increasing fire severities; (2) to assess the differences in soil properties along the fire severity gradient; (3) to model the effect of disturbance and soil legacies on the density of pine seedlings. We reconstructed fire behavior and soil heating with the First Order Fire Effects Model (FOFEM), tested the effect of fire severity on soils by nonparametric distributional tests, and modeled seedling density as a function of site, disturbance and soil legacies by fitting a GLM following a variable selection procedure. Topsoil heating differed markedly between the moderate and high severity fires, reaching temperatures high enough to strongly and permanently alter soil properties only in the latter. High fire severity resulted in decreased soil consistency and wet aggregate stability. Burned soils had lower organic matter and cations than those unburned. Pine seedlings favored low-fertility, eroded, and chemically poor sites. Establishment was facilitated by the presence of coarse woody debris, but hampered by increasing distance from the seed source. These results suggest that in dry, inner-alpine valleys, fire residuals and soil legacies interact in determining the success of Scots pine re-establishment. High severity fire can promote favorable soil conditions, but distance from the seed source and high evaporation rates of bare soils must be mitigated in order to ensure a successful restoration. [Copyright &y& Elsevier]

• Harmonised freely-available data is crucial to model forest impacts on climate change. • We summarise available datasets on forest functioning and underlying drivers. • Data for key demographic mechanisms are available at the short-term at EU level. • Lack of high-resolution harmonised EU data for genetic and physiological tree responses to climate change. • Need for Pan-European data integration effort. Climate change is expected to cause major changes in forest ecosystems during the 21st century and beyond. To assess forest impacts from climate change, the existing empirical information must be structured, harmonised and assimilated into a form suitable to develop and test state-of-the-art forest and ecosystem models. The combination of empirical data collected at large spatial and long temporal scales with suitable modelling approaches is key to understand forest dynamics under climate change. To facilitate data and model integration, we identified major climate change impacts observed on European forest functioning and summarised the data available for monitoring and predicting such impacts. Our analysis of c. 120 forest-related databases (including information from remote sensing, vegetation inventories, dendroecology, palaeoecology, eddy-flux sites, common garden experiments and genetic techniques) and 50 databases of environmental drivers highlights a substantial degree of data availability and accessibility. However, some critical variables relevant to predicting European forest responses to climate change are only available at relatively short time frames (up to 10-20 years), including intra-specific trait variability, defoliation patterns, tree mortality and recruitment. Moreover, we identified data gaps or lack of data integration particularly in variables related to local adaptation and phenotypic plasticity, dispersal capabilities and physiological responses. Overall, we conclude that forest data availability across Europe is improving, but further efforts are needed to integrate, harmonise and interpret this data (i.e. making data useable for non-experts). Continuation of existing monitoring and networks schemes together with the establishments of new networks to address data gaps is crucial to rigorously predict climate change impacts on European forests. [ABSTRACT FROM AUTHOR]

Overlaid to a general reduction of European beech and sessile oak tree growth over the recent decades in the Mediterranean Basin, tree-ring records from western Mediterranean populations display a stronger growth decrease than eastern populations. We investigate here to what extent the impact of sustained atmospheric circulation patterns in summertime can explain the observed spatial patterns of tree growth. We use Canonical Correlation Analysis, a statistical method that identifies the coupled patterns that are optimally correlated between two multivariate data sets. A general change in growth trends, shifting from a general increase during the period 1950–1981 to a decrease during the last three decades (1982–2012), can be attributed to increasing summer temperatures, which exert a dominant and negative influence on growth in both tree species across sites. However, summer precipitation has gained importance for growth, coinciding with the intensification of the geographical polarity in climate conditions across the Mediterranean Basin. This intensification during the last three decades can be traced back to a strengthening of the Summer North Atlantic Oscillation (SNAO), which imparts an east-west dipole to summer climate in this region. Under predicted persistent stronger SNAO in the future, western populations would face harsher summer conditions than central and eastern rear-edge populations, due to decreasing precipitation and increasing temperatures in the western Mediterranean Basin. These results evidence the determinant role that changes in the atmospheric circulation patterns may play in the persistence of rear-edge temperate deciduous forests in the near future. [ABSTRACT FROM AUTHOR]

Projections of landscape dynamics are uncertain, partly due to uncertainties in model formulations. However, quantitative comparative analyses of forest landscape models are lacking. We conducted a systematic comparison of all forest landscape models currently applied in temperate European forests (LandClim, TreeMig, LANDIS-II, iLand). We examined the uncertainty of model projections under several future climate, disturbance, and dispersal scenarios, and quantified uncertainties by variance partitioning. While projections under past climate conditions were in good agreement with observations, uncertainty under future climate conditions was high, with between-model biomass differences of up to 200 t ha−1. Disturbances strongly influenced landscape dynamics and contributed substantially to uncertainty in model projections (~25–40% of observed variance). Overall, model differences were the main source of uncertainty, explaining at least 50% of observed variance. We advocate a more rigorous and systematic model evaluation and calibration, and a broader use of ensemble projections to quantify uncertainties in future landscape dynamics. • The first systematic comparison of forest landscape models is presented. • Variance of model projections under several future scenarios is substantial. • Model differences explain most of the simulated variance. [ABSTRACT FROM AUTHOR]