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Fungal diversity as a key driver of soil multifunctionality along a European latitudinal gradient
Han, Xingguo; Domenech-Pascual, Anna; Donhauser, Jonathan; Zohner, Constantin M.; Mo, Lidong; Crowther, Thomas W.; Casas-Ruiz, Joan Pere; Jordaan, Karen; Ramond, Jean-Baptiste; Romaní, Anna M.; Prieme, Anders; Frossard, Aline (Elsevier, 2025-12)
Soils harbor a vast diversity of microorganisms and play a crucial role in global carbon and nutrients cycles. Yet, the extent and drivers of variations in soil microbial diversity and functioning across environmental gradients at continental scales remain poorly understood. Here, we investigated the diversity and network complexity of prokaryotic and fungal communities and their relationships with soil multifunctionality (SMF) – an integrative index for C-, N- and P-cycling functions – along a 3,000-km latitudinal transect across Europe (37° to 62°N), spanning biomes from Mediterranean drylands, temperate to boreal forests. We found that SMF followed a hump-shaped latitudinal pattern, peaking at mid-latitude temperate forests and declining toward the southern Mediterranean drylands and northern boreal forests. Fungal alpha-diversity, together with mean annual precipitation (MAP), mean annual temperature (MAT), and soil pH and C/N ratio, were key contributors to SMF across latitudes, while prokaryotic alpha-diversity had little effect. Both prokaryotic and fungal communities were predominantly structured by dispersal limitation, land cover, climate and soil properties, with fungal communities more strongly limited by spatial dispersion. Our study highlights the significant role of fungal diversity in sustaining SMF along the European latitudinal gradient and demonstrates the importance of both large-scale climatic and biogeographical factors and local edaphic and land cover variables in shaping microbial diversity. Our findings offer valuable insights for the conservation of ecosystem functions.
Intra-island variation in wind patterns on sub-Antarctic Marion Island
Schoombie, Janine; Craig, K.J. (Kenneth); Goddard, Kyle Andrew; Hedding, D.W. (David William); Nel, W.; Le Roux, Peter Christiaan (University of Pretoria, 2025-10)
Sub-Antarctic Marion Island provides a critical habitat for pelagic species, yet its terrestrial ecosystem faces increasing threats from climate change. Despite being situated in one of the windiest regions globally, the impact of changing wind patterns at the intra-island scale remains poorly understood. Existing datasets lack the spatial resolution necessary to capture fine-scale wind dynamics across the island. This study aimed to address this gap by presenting high-resolution wind speed and direction data to investigate the effects of wind on terrestrial systems. We present two complementary datasets: (1) wind measurements collected from 17 stations distributed across the island between May 2018 and March 2021, and (2) computational fluid dynamics (CFD) simulations providing wind vectors and associated properties at a 30 × 30 m resolution for heights up to 200 m above ground level. The data reveal significant differences in wind speed and direction across different geographical sectors of Marion Island. Notably, anemometers situated in the south recorded more frequent gale-force winds, while the western stations experienced calmer conditions. By using the observed wind direction frequencies, a weighted average vector plot was generated from the CFD simulations, providing an island-scale representation of spatial wind patterns across the island. These datasets offer valuable insights into variations in wind patterns, including upstream and downstream effects, and serve as a crucial resource for studying wind-driven processes affecting the landscape and ecosystem, such as seed dispersal.
Plant trait matching occurs in facilitative interactions across global drylands
Smit, Imke C.; Le Roux, Peter Christiaan; Soliveres, Santiago; Gross, Nicolas; Le Bagousse-Pinguet, Yoann; Saiz, Hugo; Abedi, Mehdi; Ahumada, Rodrigo; Arroyo, Antonio I.; Asensio, Sergio; Benoit, Richard; Blaum, Niels; Bu, Chongfeng; Eldridge, David; Fajardo, Alex; Farzam, Mohammad; Fateh, Amghar; García-Gómez, Miguel; Gaitán, Juan J.; Gonzalez, Sofia; Gozalo, Beatriz; Greenville, Aaron C.; Guirado, Emilio; Hering, Robert; Leder, Cintia V.; Li, Xinhao; Liu, Jushan; Louw, Michelle Anne; Manzaneda, Antonio J.; Marais, Eugene; Martínez-Valderrama, Jaime; Mendoza, Betty J.; Mora, Juan P.; Moreno, Gerardo; Ochoa, Victoria; Oñatibia, Gastón R.; Peter, Guadalupe; Pueyo, Yolanda; Quiroga, Emiliano; Rahmanian, Soroor; Rey, Pedro J.; Rolo, Victor; Plaza, César; Sarig, Shlomo; Selyari, Javad; Travers, Samantha; Valencia, Enrique; Wang, Deli; Wang, Lixin; Wardle, Glenda; Yahdjian, Laura; Zaady, Eli; Zhang, Yuanming; Zhou, Xiaobing; Maestre, Fernando T. (Wiley, 2025)
AIM : Plant functional traits can influence interaction outcomes between nurse and target plants through a “functional trait match”, which occurs when the traits of nurse plants ameliorate their environment, and target plants possess traits that allow them to benefit from this ameliorated environment. We investigated how the traits of putative nurse species affect interaction outcomes across global drylands and determined the functional match that promotes facilitation. We also investigated how grazing pressure and global climatic and edaphic gradients affected this trait match. LOCATION : Global drylands. TIME PERIOD : 2016–2019. MAJOR TAXA STUDIED : Vascular plants. METHODS : We used a collaborative survey conducted across 29 sites from five continents, where we gathered in situ co-occurrences of dominant species (‘nurses’) and other vascular plant species, as well as their functional traits [plant height and leaf dry matter content (LDMC)]. Climate, edaphic variables and grazing pressure were measured in situ or extracted from databases. We used a model building approach to determine the effect of dominant plant traits on interaction outcomes, and how the functional trait match between nurse and target species is affected by environmental variables. RESULTS : Tall dominant plants with conservative leaves generally had a greater positive effect on species richness and cover beneath their canopies, but these effects were strongly modulated by grazing pressure and soil pH. Target plants that were significantly associated with dominant plants tended to be shorter, and have more acquisitive leaves than dominant plants, regardless of environmental conditions. However, the difference in height and LDMC between dominant plants and negatively associated target plants was strongly affected by environmental conditions. MAIN CONCLUSIONS : Functional traits play a significant role in determining interaction outcomes between dryland plants. Facilitation in drylands is driven by a conservative-acquisitive trait match, a pattern observed regardless of grazing pressure, climate and soil conditions.
Sex-linked differentiation in commercially exploited fishes : rethinking population structure in dynamic marine environments
Gardiner, Courtney E.C.; Von der Heyden, Sophie; Matthee, Conrad A.; Nielsen, Einar E.; Pujolar, José M.; Castilho, Rita; Cunha, Regina L.; Robalo, Joana I.; Durholtz, Deon; Fairweather, Tracey P.; Kathena, Johannes N.; Henriques, Romina (Wiley, 2025)
Understanding how genomic structure links with ecological and evolutionary processes is critical for forecasting species responses to dynamic marine environments, especially in commercially exploited marine species, where fishing pressure can impact genomic integrity. Here we investigate Merluccius paradoxus, a commercially exploited demersal fish that appears to be undergoing a range expansion along the southern African coastline. Using whole-genome sequence data of individuals from across the species' distribution (n = 37), we reveal that sex-linked divergence, rather than geography, is the principal driver of genomic variation, challenging conventional assumptions of regional geographic population structure. Divergence was concentrated on autosomal regions (primarily large regions on Chromosomes 1 and 2), rather than known sex-determining (SD) regions (Chromosome 9), and did not have structural variants or extended linkage disequilibrium (LD). Instead, patterns were consistent with sex-specific directional selection acting on genes enriched for neuronal function, metabolism and muscle development, traits that are likely linked to behaviour, physiology and environmental tolerance. Males had reduced nucleotide diversity (π), low observed heterozygosity (Ho) and longer runs of homozygosity (ROH) in these regions, suggesting recent selective sweeps or a reduced effective population size (Ne). Together with spatial differences in sex distribution and genomic diversity metrics, results suggest that males and females may differ in both range dynamics and adaptive potential. As M. paradoxus continues to shift its distribution across geo-political boundaries, sex-biased adaptation may have important consequences for reproductive output, resilience and sustainable fisheries management under a changing climate. This study highlights the need to incorporate sex-linked genomic variation into conservation planning, particularly in transboundary systems vulnerable to cumulative pressures of fishing and environmental change.
Takeover vulnerability and the discipline of ESG overinvestment
Tunyi, Abongeh; Sagay, Ruth O.; Matemane, Matwale Reon (Wiley, 2026)
While takeovers serve a disciplinary role by replacing inefficient managers, the threat of takeovers may compel firms to divert attention from Environmental, Social and Governance (ESG) efforts as a strategic response to external pressure, especially when such firms are already overinvesting in ESG. We test this conjecture using a panel of 19,564 firm-year observations for NYSE and NASDAQ-listed firms from 1994 to 2019. Our findings indicate that ESG performance declines in the year preceding takeover attempts and, more generally, as firms' vulnerability to takeover bids increases. This effect is more pronounced in firms with prior ESG overinvestment, suggesting that firms respond to takeover threats by scaling back excess ESG initiatives. Further analysis reveals that this response is stronger in financially constrained firms, firms with more compliance-oriented and reputationally sensitive boards and firms where the CEO holds significant influence over the board. Conversely, the effect is weaker in firms led by highly capable managers and those with large shareholders, consistent with stronger governance constraining opportunistic ESG retrenchment under takeover pressure. Overall, our results suggest that firms' ESG decisions are shaped by takeover threats, with their response influenced by prior ESG investments, financial constraints and governance structure.