Centre for Research on Ecology and Forestry Applications

Global fluctuations in vegetation productivity are intricately tied to climatic variability, but how climate change will alter climatic limitations on productivity is unclear. Here, we used shapley additive explanation (SHAP), a novel technique based on game theory, for identifing the contributions of climatic factors to vegetation productivity. We also delineated climatic limitations on productivity and traced their temporal evolution during 1982–2018 using the SHAP values. The results identified that, in temperate, boreal, and polar zones, temperature primarily limited productivity during the early growing season, and temperature and radiation jointly limited productivity during the peack and late growing season. In contrast, water and radiation predominantly limited productivity mainly in arid and equatorial zones, respectively. We also observed an alleviated temperature but an intensified water limitations on productivity across different months. The alleviated temperature limitation was particularly notable in June for the northern hemisphere (July for the southern hemisphere), with the temperature‐constrained area decreasing significantly at a rate of 2.2‰/y (1.2‰/y). In contrast, the exacerbation of water limitation was most pronounced in June (September), with the water‐constrained area expanding significantly at a rate of 2.8‰/y (3.3‰/y). Our findings underscore the imperative for a more explicit incorporation of the impact of water limitation in understanding regional and global carbon dynamics under a warming climate.

The practice of cover crops has gained popularity as a strategy to improve agricultural sustainability, but its full potential is often limited by environmental trade-offs. Using meta-analytic and data-driven quantifications of 2302 observations, we optimized cover crop practices and evaluated their benefits for global agroecosystems. Cover crops have historically boosted crop yields, soil carbon storage, and stability, but also stimulated greenhouse gas emissions. However, combining them with long-term implementation (five years or more) and climate-smart practices (such as no-tillage) can enhance these services synergistically. A biculture of legume and non-legume cover crops, terminated 25 days before planting the next crop and followed by residue mulching, is the optimal portfolio. Such optimized practices are projected to increase agroecosystem multiservices by 1.25%, equivalent to annual gains of 97.7 million metric tons in crop production, 21.7 billion metric tons in carbon dioxide sequestration, and 2.41 billion metric tons in soil erosion reduction. By 2100, the continued implementation of optimized practices could mitigate climate-related yield losses and contribute to climate neutrality and soil stabilization, especially in harsh and underdeveloped areas. These findings underscore the promising potential of optimized cover crop practices to achieve the synergy in food security and environmental protection.

Tree-microbe interactions are essential for forest ecosystem functioning. Most plant–microbe research has focused on the rhizosphere, while composition of microbial communities in the phyllosphere remains underexplored. Here, we use 16S rRNA gene sequencing to explore differences between beech and Scots pine phyllospheric microbiomes at the European continental scale, map their functional profiles, and elucidate the role of host trees, forest features, and environmental factors such as climate and atmospheric deposition in phyllosphere microbiota assembly. We identified tree species and the associated foliar trait (specifically carbon:nitrogen ratio) as primary drivers of the bacterial communities. We characterized taxonomical and functional composition of epiphytic bacteria in the phyllosphere of beech and Scots pine across an environmental gradient from Fennoscandia to the Mediterranean area, with major changes in temperature and nitrogen deposition. We also showed that temperature and nitrogen deposition played a crucial role in affecting their assembly for both tree species. This study contributes to advancing our understanding on factors shaping phyllosphere microbial communities in beech and Scots pine at the European continental scale, highlighting the need of broad-scale comparative studies (covering a wide range of foliar traits and environmental conditions) to elucidate how phyllosphere microbiota mediates ecosystem responses to global change.

At 20 °C antibiotic exposure led to a loss of gut microbiome evenness. Gram-negative bacteria targeted by colistin were not globally affected. At 20 °C nanoplastic exposure reduced relative abundance of Actinobacteria and Firmicutes. Wolbachia genus controlled compositional shifts under nanoplastic addition. At 22 °C nanoplastic exposure reduced abundance, increased evenness, and changed gut microbiome composition. Nanoplastics and antibiotics are among the most abundant chemical pollutants of soils, but their interplay with global warming remains poorly understood. The springtail Folsomia candida (Class Collembola) is a standard model for ecotoxicological assays with potential as a bioindicator of xenobiotics. Little is known, however, about their gut microbiome and how it might respond to warming and these pollutants. We exposed populations of F. candida to nanoplastics and antibiotic under two temperatures. The antibiotic treatment consisted of colistin addition, and the nanoplastic treatment consisted of polystyrene particles (50 mg kg−1 and 0.1 g kg−1 of dry soil, respectively). Both treatments were incubated at 20 and 22 °C for two months, and the bacterial gut microbiomes of springtails were then sequenced. Exposure to nanoplastics at 20 °C decreased the abundance of the dominant bacterial phyla and families, and decreased the evenness of the gut microbiome. At 22 °C, however, the abundances and evenness of the dominant families increased. Surprisingly, Gramnegative bacteria targeted by colistin were not globally affected. And at genus-level, the endosymbiont Wolbachia controlled the compositional shifts under nanoplastic addition, potentially driving the gut microbiome. Our results also indicated that warming was a major driver modulating the impacts of the antibiotic and nanoplastics. We illustrate how the gut microbiomes of springtails are sensitive communities responsive to xenobiotics and provide evidence of the need to combine multiple factors of global change operating simultaneously if we are to understand the responses of communities of soil arthropods and their microbiomes.

Chronic reductions in soil moisture combined with high air temperatures can modify tree carbon and water relations. However, little is known about how trees acclimate their foliar structure to the individual and combined effects of these two climate drivers. We used open-top chambers to determine the multi-year effects of chronic air warming (+5°C) and soil moisture reduction (-50%) alone and in combination on the foliar anatomy of two European tree species. We further investigated how these climate drivers affected the relationship between foliar anatomy and physiology/chemistry in young downy oak and European beech trees. After 4 years, reduced soil moisture led to development of thinner leaves with a narrower epidermis and lower gas exchange for oak and beech, but to a lesser extent in the latter. In contrast, prolonged warming did not affect the anatomical and physiological/chemical traits in either species. Warming also did not exacerbate the impacts of dry soils, highlighting soil moisture as the key driver in leaf anatomical shifts. While soil moisture altered oak foliar anatomy, and the physiology and chemistry of both species, our work revealed a limited acclimation potential towards more drought-and heat-tolerant leaves as conditions become drier and warmer, suggesting potentially high vulnerability of both species to future climate predictions.

Temperature and water availability significantly influence mosquito population dynamics. We have developed a method, integrating experimental data with insights from mosquito and thermal biology, to calculate the basic reproduction number (RM) for urban mosquito species Aedes albopictus and Aedes aegypti. RM represents the number of female mosquitoes produced by one female during her lifespan, indicating suitability for growth. Environmental conditions, including temperature, rainfall and human density, influence RM by altering key mosquito life cycle traits. Validation using data from Spain and Europe confirms the approach’s reliability. Our analysis suggests that temperature increases may not uniformly benefit Ae. albopictus proliferation but could boost Ae. aegypti expansion. We suggest using vector RM maps, leveraging climate and environmental data, to predict areas susceptible to invasive mosquito population growth. These maps aid resource allocation for intervention strategies, supporting effective vector surveillance and management efforts.

Ecological theory predicts that herbivory should be weaker on islands than on mainland based on the assumption that islands have lower herbivore abundance and diversity. However, empirical tests of this prediction are rare, especially for insect herbivores, and those few tests often fail to address the mechanisms behind island–mainland divergence in herbivory. In particular, past studies have not addressed the relative contribution of top‐down (i.e. predator‐driven) and bottom‐up (i.e. plant‐driven) factors to these dynamics. To address this, we experimentally excluded insectivorous vertebrate predators (e.g. birds, bats) and measured leaf traits associated with herbivory in 52 populations of 12 oak (Quercus) species in three island–mainland sites: The Channel Islands of California vs. mainland California, Balearic Islands vs. mainland Spain, and the island Bornholm vs. mainland Sweden (N = 204 trees). In each site, at the end of the growing season, we measured leaf damage by insect herbivores on control vs. predator‐excluded branches and measured leaf traits, namely: phenolic compounds, specific leaf area, and nitrogen and phosphorous content. In addition, we obtained climatic and soil data for island and mainland populations using global databases. Specifically, we tested for island–mainland differences in herbivory, and whether differences in vertebrate predator effects or leaf traits between islands and mainland contributed to explaining the observed herbivory patterns. Supporting predictions, herbivory was lower on islands than on mainland, but only in the case of Mediterranean sites (California and Spain). We found no evidence for vertebrate predator effects on herbivory on either islands or mainland in any study site. In addition, while insularity affected leaf traits in some of the study sites (Sweden‐Bornholm and California), these effects were seemingly unrelated to differences in herbivory. Synthesis. Our results suggest that vertebrate predation and the studied leaf traits did not contribute to island–mainland variation patterns in herbivory, calling for more nuanced and comprehensive investigations of predator and plant trait effects, including measurements of other plant traits and assessments of predation by different groups of natural enemies.

Tree phenology, the timing of periodic biological events in trees, is highly sensitive to climate change. Previous studies have indicated that forest greening can impact the local climate by modifying the seasonal surface energy budget. However, the understanding of tree phenological responses to forest greening at large spatial scales remains limited. Utilizing satellite‐derived phenological and leaf area index data spanning from 2001 to 2021, herein we show that forest greening led to earlier spring and autumn phenology in both temperate and boreal forests. Our findings demonstrated that forest greening during winter and spring contributed to a reduction in surface albedo, resulting in biophysical warming and consequently advancing spring leaf phenology. Conversely, forest greening in summer and autumn induced biophysical cooling through increased evapotranspiration, leading to an earlier onset of autumn leaf phenology. Our findings highlight the significant impact of forest greening‐induced local seasonal climate changes on shaping tree phenology in temperate and boreal forests. It is crucial to consider these greening‐induced alterations in microclimate conditions when modeling changes in tree phenology under future climate warming scenarios.

Background Deadwood contains a large reservoir of carbon and nutrients in forest ecosystems, its decomposition has considerable effects on forest soil chemistry and biota. Tree functional group and nutrient inputs both have a significant influence on wood decomposition rates. However, little is known about how these factors interactively influence soil biogeochemistry through wood decomposition. Methods We examined the effects of nitrogen (N) and phosphorus (P) addition on wood decomposition of different angiosperm and gymnosperm tree species in a three-year period in a subtropical forest. We explored the outcomes for the underlying soil nutrients, microbial biomass, and saprotrophic fungal communities. Result We found that P addition, rather than N, significantly increased total C, P, as well as microbial biomass C and P concentrations in the soil beneath deadwood. These effects were particularly pronounced in the soil beneath angiosperm wood compared to gymnosperm wood, likely related to the higher decomposition rates of angiosperm wood and its sensitivity to P. Similarly, the presence and abundance of soil saprotrophic fungal communities was strongly associated with P addition, where specific fungal responses were more pronounced under angiosperm wood than gymnosperm wood. Conclusion Our study underscores the pivotal role of tree functional group in modulating the response of soil nutrient dynamics and fungal community structure beneath decomposing wood in a subtropical forest. These insights are critical for developing predictive models of soil nutrient cycles, which can help manage forest ecosystems more effectively in the face of global environmental changes.

Mapping the production of Ecosystem Services (ES) is imperative for sustainable ecosystem management. Likewise, incorporating expert knowledge enhances ES research. Here, we calculate eight multi-temporal ES indicators for mainland Portugal using a spatial modelling approach. These indicators are then integrated into the novel ASEBIO index—Assessment of Ecosystem Services and Biodiversity—which depicts a combined ES potential based on CORINE Land Cover, using a multi-criteria evaluation method with weights defined by stakeholders through an Analytical Hierarchy Process (AHP). Outputs from the modelling show how ES have changed in Portugal in relation to land use changes, including trade-offs between 1990 and 2018. The composed ASEBIO index is compared against the stakeholders’ valuation of ES potential for the year 2018. The results reveal a significant mismatch between the ES potential perceived by stakeholders and the models, with stakeholder estimates being 32.8% higher on average. All the selected ES were overestimated by the stakeholders. Drought regulation and erosion prevention have the highest contrasts, while water purification, food production and recreation are the most closely aligned among both approaches. Providing the first national overview about the status of multiple ES over a 28 year-period, our findings highlight potential disparities between data-driven and stakeholder-based evaluations. Therefore, we suggest the need for integrative strategies that consider scientific models with expert knowledge for more effective ES assessments and land-use planning. This approach could help bridge the gap between data-driven models and human perspectives, resulting in more balanced and inclusive decision-making.

With ongoing global warming, increasing water deficits promote physiological stress on forest ecosystems with negative impacts on tree growth, vitality, and survival. How individual tree species will react to increased drought stress is therefore a key research question to address for carbon accounting and the development of climate change mitigation strategies. Recent tree‐ring studies have shown that trees at higher latitudes will benefit from warmer temperatures, yet this is likely highly species‐dependent and less well‐known for more temperate tree species. Using a unique pan‐European tree‐ring network of 26,430 European beech ( Fagus sylvatica L. ) trees from 2118 sites, we applied a linear mixed‐effects modeling framework to (i) explain variation in climate‐dependent growth and (ii) project growth for the near future (2021–2050) across the entire distribution of beech. We modeled the spatial pattern of radial growth responses to annually varying climate as a function of mean climate conditions (mean annual temperature, mean annual climatic water balance, and continentality). Over the calibration period (1952–2011), the model yielded high regional explanatory power ( R ² = 0.38–0.72). Considering a moderate climate change scenario (CMIP6 SSP2‐4.5), beech growth is projected to decrease in the future across most of its distribution range. In particular, projected growth decreases by 12%–18% (interquartile range) in northwestern Central Europe and by 11%–21% in the Mediterranean region. In contrast, climate‐driven growth increases are limited to around 13% of the current occurrence, where the historical mean annual temperature was below ~6°C. More specifically, the model predicts a 3%–24% growth increase in the high‐elevation clusters of the Alps and Carpathian Arc. Notably, we find little potential for future growth increases (−10 to +2%) at the poleward leading edge in southern Scandinavia. Because in this region beech growth is found to be primarily water‐limited, a northward shift in its distributional range will be constrained by water availability.

Plants synthesize a broad array of specialized chemical compounds that mediate their interactions with the surrounding environment. Some of this chemical diversity is functional and subject to natural selection, but the factors underlying chemical evolution at the intraspecific level remain largely unknown. Here, we combined chemical, environmental and genetic data to investigate the effect of aridity on the expression of chemotypes in the invasive shrub Senecio pterophorus . We studied the variation in pyrrolizidine alkaloids (PAs), a group of specialized metabolites widespread across the families Boraginaceae, Asteraceae and Fabaceae, from native populations spanning a cline of aridity and from three cross‐continental introductions, under natural and common garden conditions. We examined whether the relationship between chemistry and aridity was compatible with a process of adaptive differentiation using a method that partitions the variance and covariance by controlling for the population neutral genetic structure. We found a consistent shift from retrorsine‐like to seneciphylline‐like compounds under increasing aridity in both natural and controlled conditions in coherence with the biosynthetic pathways. This pattern was independent of the neutral genetic structure and occurred along the environmental gradient in the native range and in a convergent manner in all nonnative regions, which suggests adaptive differentiation in response to aridity. Our findings show that the diversity of PAs in S. pterophorus has been partially shaped by aridity. Investigating how abiotic factors influence chemical evolution is key to elucidating the plant responses in future climate scenarios and the cascading effects on other trophic levels.

Late spring frosts, occurring after spring phenological events, pose a dire threat to tree growth and forest productivity. With climate warming, earlier spring phenological events have become increasingly common and led to plants experiencing more frequent and severe frost damage. However, the effect of late spring frosts after leaf-out on subsequent flowering phenology in woody species remains unknown. Utilizing 572,734 phenological records of 640 species at 5024 sites from four long-term and large-scale in situ phenological networks across the Northern Hemisphere, we show that late spring frosts following leaf-out significantly delay the onset of the subsequent flowering by approximately 6.0 days. Late-leafing species exhibit greater sensitivity to the frosts than early-leafing species, resulting in a longer delay of 2.5 days in flowering. Trees in warm regions and periods exhibit a more pronounced frost-induced flowering delay compared to those in cold regions and periods. A significant increase in the frequency of late spring frost occurrence is observed in recent decades. Our findings elucidate the intricate relationships among leaf-out, frost, and flowering but also emphasize that the sequential progression of phenological events, rather than individual phenological stages, should be considered when assessing the phenological responses to climate change.

Trees, which exist in the biosphere, serve as vital connectors among the atmosphere, hydrosphere, biosphere, and lithosphere. Tree growth is affected by Earth-system processes and records key interactions among Earth spheres. The periodicity and variability of wood formation are evident in the form and width of rings. The accurate dating, long annual to seasonal records, sensitivity to environmental changes, tree ring studies have played significant roles in examining the connections between climate changes and human society evolution. Although climate signals have received most of the attention in tree ring studies, the growth variance explained by climate is less than 50% for most sites. In addition to uncertainties arising from the nonlinear responses of trees, changes in core Earth system processes can lead to alterations in solar radiation, heat exchanges, precipitation redistribution, nutrition status, and geomorphic conditions, all of which may impact tree-ring formation. The gradual accumulation of tree-ring data worldwide, combined with Earth-system monitoring, allows for the decoding of such subtle information. Through the analysis of a large amount of tree-ring data at regional to global scale, new patterns can be uncovered, which are not discernible at local scales, and new processes and underlying mechanisms can be proposed. With the nature of connections in both space and time, we expect tree-ring data to be essential spatiotemporal tunnels linking Earth systems and helping address the challenges faced by Earth system science in understanding the complex interrelationships among biological, geochemical, climate, economic, and socio-ecological systems.

Aim Global warming has highlighted the importance of understanding the role of thermal tolerance as a driver of species distributions, especially for ectotherms. Here we analyse interactions between latitude, elevation and arboreality as predictors of geographic patterns of thermal tolerance in ants. Location The collected data are distributed globally. Methods We first tested the effect of latitude, elevation and its interactive effect on ant CTmax and CTmin. Second, we tested whether CTmax and CTmin are phylogenetic clustering. Finally, we tested whether CTmax and CTmin can be explained by nesting microhabitat (ground vs. tree‐nesting species) and whether the probability of occurrence of tree‐nesting species along thermal gradients helps explain the global pattern in ant CTmax. Results CTmax and CTmin displayed high and low phylogenetic signals respectively and therefore showed different responses to geographic gradients. Notably, we found that CTmax was higher in higher latitudes. This was explained by a lack of elevational turnover at high latitudes among tree‐nesting species, which are exposed to warmer microclimates and have higher CTmax compared with ground‐nesting species. CTmin decreased with elevation at low latitudes, but did not vary with elevation at higher latitudes. Main Conclusions Our findings highlight the important influence of arboreality on the macroecology of thermal tolerance, substantially modifying traditional notions of variation along latitudinal and elevation gradients.

Data spaces are conceptualised as a trusted and secure distributed data ecosystem through which to exchange resources in the Web. Several efforts define guidance toward data space implementation, such as reference architectures and frameworks. As yet, the proposed data space solutions do not provide common and mature implementation options yet, and this gap between concept and implementation risks confusing users and developers. However, well-recognised organisations have been developing solutions and standards that address interoperability and good data exchange practices for decades, especially in the domain of geospatial information and remote sensing. Therefore, this paper compares the available solutions, providing the mapping and integration of the proposed blueprints to available interoperable standards. This concrete mapping, followed by a discussion with experts, results in a proposal of integrated reference data space building blocks, and an overview of the related standards and solutions. It is designed to support the effective practical implementation of data spaces and to guide future solution developments. This work can form the base for effective collaboration among different organisations, clearly identifying their scopes. A key role is apparent for standards and use cases from the remote sensing and geospatial domains, which have achieved wide adoption and maturity over the past years.

Different theories have been proposed to explain the phenotypic changes observed in island lineages, but it remains unclear if predictable evolutionary trajectories can be identified within island communities. Using a 3D functional space approach, we tested whether insular endemic species tend to evolve towards apparent holes in niche space (expecting niche filling) or tend to become generalists, that is, moving towards the centre of the functional space (expecting niche expansion). We tested these two hypotheses in 378 insular endemic species from 24 islands of 8 archipelagos, including 177 prehistoric anthropogenically extinct species. Analyses were conducted with and without accounting for species size difference. We found that 57% of island endemic species evolved towards more unoccupied regions of the global morphospace (i.e. more distinct body sizes compared to the ones of their ancestors), suggesting a tendency for niche filling. When adjusted traits for body size, we found that half of the endemic species (50%) showed more distinct trait values than their ancestors. Results also revealed that certain dietary niches (terrestrial herbivores and nectarivores) evolved distinct body sizes more frequently. Differences noted between islands and archipelagos suggest that biogeographic factors may influence evolutionary trajectory and interactions between these two hypotheses. Our study confirms that extinct species occupied specific niches that have been left vacant, suggesting that these evolutionary ‘oddities’ could be more sensitive to extinction. Overall, it calls for a global assessment of the avian functional diversity lost from recent extinctions. Read the free Plain Language Summary for this article on the Journal blog.

Resource demand by soil microorganisms critically influences microbial metabolism and then influences ecosystem resilience and multi-functionality. The ecological remediation of abandoned tailings is a topic of broad interest, yet our understanding of microbial metabolic status in restored soils, particularly at the aggregate scale, remains limited. This study investigated microbial resources within soil aggregates from revegetated tailings and applied a vector model of ecoenzymatic stoichiometry to examine how different vegetation patterns (grassland, forest, or bare land control) impact microbial resource limitation. Five-year vegetation restoration significantly elevated carbon (C) and nitrogen (N) concentrations and their stoichiometric ratios in soil aggregates (approximately 2-fold), although these increases were not translated to in the microbial biomass and its stoichiometry. The activities of C- and phosphorus (P)-acquiring extracellular enzymes in these aggregates increased substantially postvegetation, with the most pronounced escalation in macroaggregates (>0.25 mm). The vector model results indicated soil microbial metabolism was colimited by C and P, most acutely in microaggregates (<0.25 mm). This colimitation was exacerbated by monotypic vegetation cover but mitigated under diversified vegetation cover. Soil nutrient stoichiometric ratios in vegetation restoration controlled microbial resource limitation, overshadowing the impact of heavy metals. Our findings underscore that optimizing resource allocation within soil aggregates through strategic revegetation can enhance microbial metabolism in tailings, which advocates for the implementation of diverse vegetation covers as a viable strategy to improve the ecological development of degraded landscapes.