Pedro Jose Rey

Sustainable management is essential for maintaining biodiversity, ecosystem services, and the long-term resilience of Mediterranean olive systems. Yet, the adoption of biodiversity-friendly practices remains limited despite growing evidence of their environmental, social, and economic benefits. Understanding the drivers of stakeholders’ decision-making is critical for designing locally adapted policy interventions that support sustainable transitions in olive cultivation. We surveyed 104 stakeholders engaged in olive cultivation, including farmers, advisors, researchers, commercial actors, representatives of environmental organisations, educational institutions, and public authorities across four major European olive-producing countries: Spain, Italy, Portugal, and Greece. Responses concerning management practices and perceived constraints were more frequently associated with production-related characteristics, particularly professional role, cultivation intensity, and time investment in the olive sector, than by socio-demographic factors. However, perceived importance scores for biodiversity, ecosystem services, and external support were consistently high across all stakeholder groups. Environmental pressures, including climate-related stressors, soil degradation, and pest outbreaks, emerged as the most frequently reported challenges, alongside economic uncertainty, administrative complexity, and limited access to knowledge exchange and implementation support. Stakeholders identified agroecological management, biodiversity and ecosystem service support, market and technological innovation, and social and institutional transformation as key opportunities for accelerating sustainable transitions. These findings suggest that high perceived importance of biodiversity and ecosystem services can coexist with substantial constraints on sustainable management. They highlight the relevance of policies that address financial risks and administrative burdens, improve access to support, and strengthen locally adapted advisory services and knowledge-exchange networks under the Common Agricultural Policy.

Pollination is a key ecological process sustaining biodiversity and food security, yet global patterns of plant–pollinator specialization remain unresolved. Using a global dataset of quantitative plant–pollinator networks (>3,400 networks, >110,000 interactions), we show that specialization is latitudinally structured, but not as a single directional pattern. We find no consistent monotonic increase or decrease in specialization towards the Equator. Instead, network-level and pollinator specialization peak at low northern latitudes near the tropical–subtropical boundary, whereas plant specialization is hemispherically asymmetric. Climate is most often the best-supported predictor of specialization compared with latitude, biodiversity and environmental productivity. Network-level specialization declines with increasing mean annual temperature, with strong group-specific differences. Precipitation exerts nonlinear effects: plant specialization peaks at intermediate precipitation but is lower at the wettest sites, whereas pollinator specialization is lower at intermediate precipitation, although often in interaction with temperature. Pollinator groups diverge strongly, especially in contrasting precipitation-related patterns between birds and insects. These findings show that global plant–pollinator specialization is structured by latitude and climate in complex and taxon-specific ways, with implications for uneven responses of pollination networks to future climatic change.

Aridity alters soil carbon (C), nitrogen (N) and phosphorus (P) stoichiometry, yet the implications of these processes for soil microbial functional traits and potentials at the genomic level remain poorly synthesized. Here we combine measurements of soil C, N and P pools and ratios with shotgun metagenomes from 200 natural ecosystems spanning major biomes worldwide. Across sites, increased aridity is associated with lower soil C:N and N:P (and C:P) ratios and with a coordinated shift in microbial functional potential. Genes linked to catabolic resource acquisition—including carbohydrate-active enzymes and pathways for degradation of plant litter and organophosphorus compounds—are declined as C becomes relatively scarce. In contrast, genes supporting anabolic investment in growth and drought resistance, such as RNA transcription, protein synthesis and intracellular transport, are increased. These patterns indicate that aridity-related change in soil elemental ratios is coupled to a broad shift from catabolic to anabolic strategies in soil microbiomes. By linking soil elemental ratios to microbial functional traits across biomes, our study provides a framework for anticipating how climate-driven drying may reorganize microbial metabolism with consequences for carbon and nutrient cycling.

Microbes, as the planet's most abundant and diverse organisms, drive soil functions globally and are vulnerable to environmental stressors triggered by global change. Yet, knowledge regarding the impacts of multiple environmental stressors on their functional profiles as well as the consequences for soil functionality largely remains unknown. Here, we analyze two global-scale datasets including information on soil metagenomics and multiple environmental stressors. We find that across terrestrial ecosystems worldwide, up to 60% of all functional genes significantly shift when soil microbes experience the high-level of concurrent stressors. In this regard, the relative abundances of genes involved in microbial growth are negatively linked to the increasing number of stressors. Conversely, those genes linked to stress resistance and energy production exhibit positive responses. Taken together, our findings highlight a significant restructuring of global soil functional microbiomes in response to multiple environmental stressors. Consequently, such restructuring drives community-level shifts in matter and energy reallocations, thereby impacting the maintenance of soil functionality under the projected global change.

Recovery debt (RD) quantifies the interim deficit of biodiversity and function during the recovery process after disturbance. Unlike typical recovery indices derived from data on experimental-control comparisons, RD further considers the target (reference) biodiversity level, modelling the rate at which it is approached over time. However, the application of the RD approach to active restoration has not been explicitly implemented to date. Here, we extend the RD framework to evaluate active ecological restoration in agricultural systems, defining the onset of recovery as the shift from intensive to wildlife-friendly management. We applied this approach to assess short-term pollinator recovery in 14 olive groves across a gradient of farming intensification and landscape complexity in southern Spain. Restoration actions included adopting low-intensity ground cover management and actively restoring field margins. At one, three, and five years post-restoration, we assessed community responses by quantifying bee abundance, species richness, plant–bee network properties, and flower visitation rates. Reference systems were defined by olive groves in complex landscapes with low-intensity herb cover management and organic farming practices. Following restoration, the RD of bee abundance decreased from 71% to 55%. We found no significant effects of pre-intervention agricultural management on RD. Instead, across sites, the reduction of the RD (i.e., recovery) of bee abundance, richness, network connectance and flower visitation rate was strongly mediated by the availability of high-quality semi-natural areas in the surrounding landscape and by the ecological contrast created by restoration interventions at both the farm and floral patch levels. RD for other network metrics showed no significant pattern of variation. Our study demonstrates that wildlife-friendly management and targeted habitat restoration can rapidly reduce recovery debt for bee abundance and function in permanent agroecosystems. However, the recovery of more complex interaction-network properties likely requires longer timescales.

Premise: Insect herbivory is a major biotic factor shaping plant populations and driving the evolution of defensive traits. Polyploidy (whole‐genome duplication) often induces substantial phenotypic and genotypic changes that may affect species interactions, including herbivory. However, natural variation in herbivory responses and the drivers of resistance and tolerance across heteroploid lineages remain poorly understood. Methods: We conducted a bioassay to quantify variation in plant damage and tolerance to locust herbivory across multiple diploid and allotetraploid populations of the Brachypodium distachyon species complex, a model system comprising two diploid species ( B. distachyon and B. stacei ) and their allotetraploid derivative ( B. hybridum ). For each species, we also examined which plant functional traits were associated with resistance and tolerance to herbivory. Results: Herbivory reduced maternal fitness across the species complex, although its magnitude depended on species and the fitness component considered. Our results do not support enhanced herbivory resistance or tolerance in the allotetraploid lineage: Levels of plant damage in B. hybridum were comparable to those of one diploid parent ( B. distachyon ), and diploid B. distachyon had higher tolerance than B. hybridum for two of three fitness estimators. Variation in resistance was associated with differences in plant traits, particularly C:N ratio and silica content. In B. distachyon , tolerance was negatively associated with silica and water content, suggesting allocation trade‐offs between resistance‐ and tolerance‐related traits. Conclusions: Overall, our findings indicate that variation in herbivory responses across Brachypodium populations is more closely linked to population history and trait differentiation than to polyploid formation per se.

Drivers of non-native plant success in drylands are poorly understood. Here we identify functional differences between dryland native and non-native perennial plants and assess how biotic, abiotic and anthropogenic factors shape the success of the latter. On the basis of plant community and functional trait data from 98 sites across 25 countries, we report a total of 41 non-native plant species at 31 sites. Non-natives tend towards faster growth strategies than natives. Non-native plant richness is higher at sites with greater grazing pressure and under environmental conditions associated with higher soil fertility, decomposition and fungal richness—conditions that tend to occur in less arid regions—and lower where native plant and herbivore richness are greater. Non-native plant cover correlates positively with grazing pressure and negatively with native plant richness. Taken together, our results suggest that non-native plant success in drylands is facilitated when high grazing pressure coincides with elevated resource availability. Such context-dependence of non-native plant success and linkages with native plant and herbivore diversity highlight the need for managing grazing and conserving biodiversity across the world’s drylands.

Pesticide use and habitat loss are major anthropogenic drivers of bee decline, raising global concerns about impaired crop pollination. However, the relative importance of these stressors and their combined impact on bee assemblages comprising species with different traits, such as body size or nesting strategy, remains unknown. Here we addressed these key knowledge gaps in a global quantitative synthesis analysing bee assemblage data from 681 crop fields across three continents. We found that both local pesticide hazards and decreasing proportions of semi-natural habitats in surrounding landscapes negatively affected wild bee abundance and species richness in crop fields, while pesticides additionally reduced functional and phylogenetic diversity. Semi-natural habitat availability did not buffer against these negative pesticide effects, nor did we identify any specific traits rending bees more vulnerable to one of the two drivers. Our findings highlight the pressing need to reduce non-target effects of pesticide use and emphasize that conservation and restoration of semi-natural habitats successfully promote wild bees, but are insufficient strategies to mitigate pesticide-driven losses of wild bee pollinators from crop fields.

Drought is the main abiotic stress that impacts biomass productivity and grain yield in crops. Dehydrins are part of the Late Embryogenesis Abundant protein family. They are typically upregulated under water-limited conditions, playing a key role in plant response and adaptation to stressful environments. However, the specific function of dehydrins and their relationship with plant functional traits and drought-related physiology remain poorly understood. Brachypodium distachyon L. is a well-studied monocot model plant for temperate grasses, yet DHN proteins in Brachypodium have not been extensively researched. To our knowledge, this is the first functional validation in Brachypodium of a dehydrin gene (BdDHN3) demonstrating a causal improvement in drought tolerance, together with a comparative analysis of BdDHN3 expression across 11 genetically distinct lines. Thus, we first examined variations in the expression level of the BdDHN3 gene among 11 genetically distinct B. distachyon inbred lines to assess the genetic consistency of gene expression. Second, we generated transgenic plants with overexpression constructs in the Bd21 line to analyze drought response at both the functional and genetic expression levels. On average, BdDHN3 expression was 447.2 times higher under drought conditions compared to the control across B. distachyon lines. Overexpression of BdDHN3 resulted in enhanced drought tolerance, as plants overexpressing BdDHN3 retained more water, exhibited lower cell damage, and had higher proline contents under water stress conditions compared to wild-type (WT) plants. These findings suggest that BdDHN3 may play an important role in the plant response to drought stress. Given its proximity and gene synteny to other significant temperate cereal crops, our results indicate that DHN3 proteins may also be relevant for temperate grasses with socio-economic importance.