Biology subjects

Mueller, J.

Publications and source records attributed to Mueller, J..

At least 19 recordsLinked to original sources

bioRxiv2026

Viscoelastic liquid lassos extend the defensive reach of termite soldiers

Small animals face a severe size asymmetry when defending themselves against larger predators. Soldiers of Nasutitermes termites overcome this constraint by ejecting tens of nanoliters of secretion through a cephalic nozzle, the nasus. High-speed imaging in the field, rheometry, micro-CT, flow simulation, behavioral assays, and scaled experiments reveal a multistage defense. A near-linear nasus and shear-thinning secretion support rapid ejection. Lateral head oscillation at 5-30 Hz couples with rope-coiling instability to distribute the filament as loops and meanders, a ``liquid lasso,'' reaching up to three body lengths. After deposition, the apparent extensional viscosity increases 8- 80-fold, delaying breakup as the secretion cures into a persistent adhesive. The lasso coats the sensory and grooming structures of predatory ants, and tethers them to the substrate. Synthetic experiments show that nozzle geometry, orientation, height, and oscillatory motion jointly control ejection and coverage, providing design principles for deploying small volumes of time-evolving viscoelastic materials.

biophysics↗

bioRxiv2026

Rewiring central carbon metabolism reveals a trade-off between yield and production rate in poly-γ-glutamic acid synthesis by Bacillus subtilis

Improving carbon yield and process time is a key requirement for the industrially viable production of biopolymers. During poly-{gamma}-glutamic acid production with Bacillus subtilis, a considerable fraction of the carbon source is diverted into by-products. These originate from accumulating pyruvate, constraining carbon flux towards glutamate synthesis. Disrupting by-product pathways reduces their secretion, but the underlying imbalance at the pyruvate node persists. Here, we rewired the central carbon metabolism to redirect glycolytic flux from pyruvate formation towards oxaloacetate and 2-oxoglutarate in an improved medium. Deletion of pyruvate kinase combined with heterologous expression of phosphoenolpyruvate carboxylase established an alternative anaplerotic entry route into the TCA cycle. Subsequent disruption of gluconeogenetic reactions (OF5) reduced by-product formation by 81% and increased {gamma}-PGA yield to 0.41 g g-1 glucose, but lowered the glucose uptake rate. Alternatively, disruption of the TCA cycle downstream of 2-oxoglutarate combined with enhanced glutamate synthesis (OF4.2) increased substrate uptake and improved the {gamma}-PGA production rate by 39% compared to the wild type, while product and by-product titers remained comparable. Both strategies thus revealed a trade-off between improved yield or production rate. Subsequent 13C metabolic flux analysis and intracellular metabolite profiling revealed distinct carbon routing phenotypes. While strain OF5 maintained carbon within the TCA cycle, OF4.2 cycled carbon between oxaloacetate, malate and pyruvate, thereby altering redox and energy balances. These results highlight the need for coordinated control of carbon flux, redox metabolism and energy supply for improving {gamma}-PGA synthesis, and identify the oxaloacetate-malate-pyruvate node as a promising strain engineering target.

microbiology↗

bioRxiv2026

Forest biodiversity benefits from warmer microclimate, but only in colder regions

The diversity of many forest-dwelling organisms depends on forest structure, but it remains unknown to which degree this is mediated by microclimatic temperature, and whether microclimatic buffering is universally beneficial for forest biodiversity. In 234 broad-leaved forest plots across nine climatically differing regions in Germany, we measured micro- and macroclimatic temperatures, canopy cover, and deadwood volume after experimental manipulations of forest structure through thinning operations and gap cuts. We surveyed 21 taxonomic groups, representing plants, bacteria, fungi, and animals, to assess how their diversity depended on the predictors. Multi-taxon diversity, and diversity of ten separate taxonomic groups, increased from closed to open canopies. Only necrophagous beetles were more diverse in closed stands. These effects of canopy cover on diversity were partly mediated by microclimatic temperatures. Thereby, diversity responses to microclimatic temperature depended on the macroclimatic context. In regions with colder summers, locally warmer microclimates in canopy gaps had strong positive effects on biodiversity, while these effects were not found in regions with warmer summers. Consequently, management strategies aimed at multi-taxon forest diversity conservation should be chosen based on the regional climate, favoring canopy gaps primarily in colder regions, and taking future climate warming into consideration.

ecology↗

bioRxiv2026

Sample coverage standardization ranks species richness of saproxylic beetles across European tree genera

Aims In forest ecosystems, tree species composition and diversity are fundamental drivers of biodiversity and many species are closely associated to specific tree species as hosts. Saproxylic diversity across tree species may be shaped by interactions between ecological and environmental factors, such as resource availability. However, a throughout and unbiased quantification of diversity across tree species is missing. We investigated patterns an drivers of saproxylic beetle diversity across European tree genera while accounting for differences in sampling effort. Location Europe Methods We used a large dataset, of 25 studies, comprising 500,000 deadwood-dependent beetles, representing 1041 saproxylic beetle species, sampled from 29 tree genera. We accounted for sampling effort by estimating diversity using coverage-based standardization across Hill numbers. We than used linear models to identify drivers of saproxylic beetle diversity across tree genera and assessed differences in community composition using Nonmetric Multidimensional Scaling (NMDS). Additionally, the most abundant beetle families were identified for a subset of 14 genera. Results Quercus supported the highest richness of infrequent, frequent, and highly frequent species, while Fagus exhibited the highest observed (unstandardized) species richness. Beetle communities were less differentiated when focusing on infrequent species, whereas tree genera were separated when focusing on frequent and highly frequent species. In addition, we found that resource availability and maximum tree height best predicted infrequent beetle diversity, whereas resource availability was the main driver of frequent species. In contrast, the same analyses for unstandardized data indicated postglacial occurrence as an important factor for infrequent species. Main conclusions Although resource availability supported the species area hypothesis, standardized data revealed higher richness on smaller trees, partly contradicting this pattern. Our results highlight the importance of accounting for sampling bias and promoting tree diversity, particularly oaks, to sustain saproxylic beetle diversity.

ecology↗

bioRxiv2026

The Scm FCS finger binds the Pcl Tudor domain to link canonical PRC1 and PRC2.1 in Drosophila

Canonical Polycomb Repressive Complex 1 (PRC1) was previously reported to selectively associate with Polycomb Repressive Complex 2.1 (PRC2.1) in cross-linking-based affinity purification experiments from Drosophila embryos, but the molecular basis of this interaction has remained unresolved. Here, we established an affinity-purification strategy using cryo-milled Drosophila embryos that recovers intact canonical PRC1 together with the complete PRC2.1 complex without chemical cross-linking. Using AlphaFold3 to systematically model interactions between canonical PRC1 and PRC2.1 subunits, we identified a single high-confidence interface between the FCS finger of the canonical PRC1 accessory subunit Sex comb on midleg (Scm) and the atypical Tudor domain of the PRC2.1 accessory subunit Polycomblike (Pcl). Recombinant Scm FCS finger and Pcl Tudor domain formed a stable complex in vitro, as demonstrated by size-exclusion chromatography and native mass spectrometry. Structure-guided mutagenesis validated the predicted interface: point mutations in either interaction partner abolished complex formation, whereas complementary charge-reversal mutations restored binding. These findings identify the Scm-Pcl interaction as the molecular basis for the selective association between canonical PRC1 and PRC2.1 in Drosophila and reveal that communication between these complexes is mediated by a direct interaction between these accessory subunits.

biochemistry↗

bioRxiv2025

Salicylic acid-induced alkalinization of the apoplast requires TRANSMEMBRANE KINASE 1 and results in growth attenuation

The phytohormone salicylic acid (SA) has a key role in regulating plant growth and stress response. In the past, most of the growth-related SA functions have been explained by crosstalk with the master growth regulator auxin. By affecting polarity of auxin transporters, SA changes auxin distribution in the root and inhibits growth of the main root and activates lateral root formation. However, only recently there is evidence emerging that SA impacts growth processes independently of nuclear auxin signalling, possessing yet unknown mechanistic functions. Here we show that SA activity depends on TRANSMEMBRANE KINASE 1 (TMK1) resulting in apoplast alkalinization and growth restriction. SA treatment prevents phosphorylation and activation of plasma membrane (PM) H+-ATPases at the cell surface and does not depend on the auxin receptor Auxin Binding Protein 1 (ABP1). We suggest that alkalinization of the apoplast by SA serves as mechanism to balance stress response and growth.

plant biology↗

bioRxiv2025

Development of a Novel Methyl Cellulose Hydrogel with Physiologically-Relevant Controlled Ethanol Release for Cervical Dysplasia Ablation

Cervical cancer is a leading cause of death in women in low- and middle-income countries (LMICs) and disproportionately affects women of minority populations in the US, primarily due to a lack of infrastructural support for specialized care. A promising treatment which meets accessibility requirements is ethyl cellulose (EC)-ethanol ablation--inducing necrotic cell death through application of ethanol to kill precancerous cells. While previous work focused on injecting EC-ethanol to ablate high-grade dysplasia (which can reach depths up to 5 mm below the tissue surface), low-grade dysplasia requires a different delivery method as it is much more superficial (reaching depths of only 1-3 mm). Here, we have developed a topical gel for local ethanol ablation of low-grade dysplasia with minimal damage to healthy cervical tissue. We investigated several gellants, including methyl cellulose (MC), EC, and Pluronic(R) F-127, to develop an ethanol gel that meets parameters for low cost and topical ease of use. Formulations with F-127 did not form gels with ethanol. Formulations with EC and MC were gel-forming. The MC-based formulations formed more uniform and stable gels that hold their own weight while still being spreadable at both room and body temperatures, key criterion for local cervical application. The optimal formulation contained 70% ethanol, 20% water, and 10% MC. One gram of this formulation represents approximately 5{cents} material cost, and formulated gels were stable for one week at least when stored at 4, 22, 30, and 37 {degrees}C. Additionally, the MC gel achieved localized ablation within 5 minutes after application to cervical cancer cells in-vitro. Taken together, we have developed a low-cost, efficacious, MC-based ethanol gel fit for translational testing to treat low-grade cervical dysplasia. This gel may provide a novel treatment option for women in LMICs, without causing major side effects or loss of healthy cervical tissue. Translational Impact StatementWe have developed a low-cost, efficacious, methyl cellulose-based ethanol gel fit for translational testing to topically treat low-grade cervical dysplasia. This addresses the need for a novel and accessible treatment option for women in low- and middle-income countries, which will not cause major side effects or loss of healthy cervical tissue. Ethics StatementAll work herein are the authors own original work. Authors have no conflicts of interest to disclose. Primary funding for the project was startup funds provided by the University of Maryland. All data available upon request.

bioengineering↗

bioRxiv2025

Chemical proteomics decrypts the kinases that shape the dynamic human phosphoproteome

Mass-spectrometry-based phosphoproteomics enables the analysis of thousands of protein phosphorylation events across the human proteome. However, there is a lack of scalable, hypothesis-free, and statistically sound approaches for discovering, evaluating, and falsifying kinase::substrate relationships (KSRs). Here, we developed a new concept termed potency-coherence analysis. By measuring and integrating 17 million peptidoform-specific dose-response curves for 133 kinase inhibitors with known targets and affinities, we could critically re-evaluate published KSRs and discover thousands of potency-coherent and motif-plausible new KSRs for 96 human kinases. Application of these high-confidence KSRs enabled the estimation of kinase and signaling pathway activities in cancer patient biopsies. This unified and extendable framework has been implemented in ProteomicsDB to aid researchers in understanding the human phosphoproteome in health and disease.

systems biology↗

bioRxiv2025

Multi-strain Analysis of Pseudomonas putida Reveals the Metabolic and Genetic Diversity of the Species.

Pseudomonas putida is a gram-negative bacterial species increasingly utilized in biotechnology due to its robust growth, ability to degrade aromatic compounds, solvent tolerance, and genetic tractability. In this study, we report a comprehensive multi-strain analysis of 164 P. putida strains. We performed whole-genome sequencing and hybrid assembly for 40 strains, contributing a [~]8% increase to the available genomic data for P. putida. Furthermore, high-throughput phenotypic profiling using the Biolog phenotype microarray system for 24 strains on 190 unique carbon sources, along with 15 aromatic compounds not present on Biolog plates, yielded 4,920 unique strain-phenotype measurements. These data were leveraged to curate GEMs for 24 representative strains, including a refined model for strain KT2440, which comprised 1,480 genes and 2,191 metabolites, achieving a prediction accuracy of 91.2% in carbon utilization. Systematic comparison of genomes and GEMs revealed both conserved core pathways and significant allelic and functional divergence across strains, highlighting strain-specific variation in aromatic degradation. While pathways for protocatechuate and phenylacetate degradation were widely conserved, metabolic capabilities for compounds such as ferulate, phenol, and cresols varied markedly, suggesting adaptation to distinct ecological niches. Alleleome analysis of enzymes such as PcaI and PcaJ revealed distinct, functionally similar clades, indicating possible convergent evolution or horizontal gene transfer. These results provide computable resources and models for selecting P. putida strains with desired traits for biomanufacturing and bioremediation and offer insights into the evolution and phylogeny of the P. putida species.

bioengineering↗

bioRxiv2025

Cysteine availability tunes ubiquitin signaling via inverse stability of LRRC58 E3 ligase and its substrate CDO1

Cellular responses to amino acid fluctuations often hinge on ubiquitin-mediated control of metabolic enzymes, yet the underlying E3 ligase pathways remain incompletely defined. Using quantitative proteomics and active cullin-RING ligase (CRL) profiling, we identify LRRC58 as a cysteine-responsive substrate receptor whose stability increases sharply under cysteine starvation. Proteomics reveals an inverse relationship between LRRC58 and the metabolic enzyme cysteine dioxygenase 1 (CDO1), suggesting a cysteine-linked regulatory axis. Biochemical reconstitution and cryo-EM structures show that LRRC58 forms an active CUL2-or CUL5-based CRL that selectively positions CDO1 for ubiquitylation at Lys8. By contrast, targeted protein degradation via the VHL-based CRL is achieved by recruitment of a distinct surface of CDO1, and more promiscuous ubiquitylation independent of Lys8. Together, our proteomics-guided discovery pipeline, cellular stability studies, and structural analyses uncover a metabolically-tuned LRRC58-CDO1 pathway that links cysteine availability to selective proteasomal turnover, reveals principles of metabolite-regulated CRL activity, and showcases mechanisms distinguishing endogenous and targeted protein degradation.

biochemistry↗

bioRxiv2025

GLYATL1 is associated with metabolic and epigenetic changes and with endocrine resistance in luminal breast cancer

Estrogen receptor alpha (ER)-positive luminal breast cancer is commonly treated with aromatase inhibitors (AI) to block estrogen signaling; however, resistance frequently develops, limiting therapy success. We observed that GLYATL1 (Glycine-N-Acyltransferase Like 1) expression is upregulated in AI-resistant breast cancer cell models and in patients undergoing AI therapy, correlating with poorer survival. Here we demonstrate that GLYATL1 promotes resistance to estrogen deprivation by elevating succinate levels and altering epigenetic histone marks associated with active transcription. Knockdown or knockout of GLYATL1 reverses these effects and reduces proliferation under estrogen-deprived conditions. Notably, GLYATL1 expression is positively regulated by estrogen receptor alpha signaling independently of estrogen. These findings reveal GLYATL1 as a metabolic and epigenetic mediator of endocrine therapy resistance, suggesting it as a potential target to overcome AI resistance in luminal breast cancer.

cancer biology↗

bioRxiv2025

Microclimatic heterogeneity is associated with forest structural complexity and biodiversity

Forest microclimates, their dependence on forest structure, and their impact on biodiversity are crucial for future forest management under climate change. However, standard approaches for measuring forest microclimates do not capture within-plot heterogeneity, which, according to the habitat heterogeneity hypothesis, is a key driver of local biodiversity. We quantified horizontal and vertical microclimatic heterogeneity within 30 broad-leaved forest plots in Central Europe using a three-dimensional design with high spatial resolution. Moreover, we examined whether microclimatic heterogeneity differs among silvicultural treatments and whether it can be predicted using forest structure indices derived from laser scanning. Additionally, we explored the relationship between microclimatic heterogeneity and biodiversity. In the understory of canopy gaps, warm and cold habitats co-existed in close proximity, leading to a high horizontal microclimatic heterogeneity. In closed stands with high structural complexity, we found steep gradients of increasing temperature and vapor pressure deficit from the ground to the canopy during mid-day. Canopy cover and forest structural complexity were strong indicators of microclimatic heterogeneity. We found positive relationships between herb layer temperature heterogeneity and the diversity of plants, Hymenoptera, and Diptera. Our results demonstrate that single-point measurements fail to capture the substantial microclimatic heterogeneity within plots, potentially misrepresenting the conditions experienced by forest species. However, laser scanning provides reliable indicators for within- plot microclimatic heterogeneity. With canopy gaps featuring high horizontal microclimatic heterogeneity and promoting the biodiversity of several taxonomic groups, we argue that managing forests for maximized temperature buffering should not be the only strategy to conserve forest biodiversity. HighlightsO_LIHigh small-scale horizontal microclimatic heterogeneity in canopy gaps C_LIO_LISteep vertical microclimatic gradients in closed-canopy forests C_LIO_LICanopy cover and structural complexity: indicators for microclimatic heterogeneity C_LIO_LIPositive relationship between herb layer temperature heterogeneity and biodiversity C_LI

ecology↗

bioRxiv2025

The Invisible Heterogeneity of a Forest -- Beta Diversity of Volatiles

Forest structural heterogeneity affects biodiversity, yet how changes in forest structure influence the spatial patterns of forest chemical heterogeneity remains poorly understood. Volatile organic compounds (VOCs) create invisible chemical landscapes that influence forest ecosystem processes, but whether VOC {beta}-diversity patterns respond to silviculture or disturbance caused heterogeneity remains unknown. We quantified how enhanced structural beta complexity (ESBC) treatments affect VOC {beta}-diversity patterns and investigated potential drivers and ecological effects in temperate production forests. Using the experimental BETA-FOR framework, we sampled ambient forest air at the forest floor and 1 m heights across 234 forest patches in six German regions using Tenax/Carboxen adsorbent traps analyzed via TD-GCMS. Results from generalized linear beta regression models showed that {beta}-diversity of VOCs increased significantly at 1 m height in ESBC forests compared to control forests, but this increase was not significant at the forest floor. In contrast to studies on plants, fungi and animals, the main driver for increasing beta-diversity in VOCs was not the heterogeneity of canopy openness, but the amount of deadwood. Using saproxylic beetles as a test group, we found that saproxylic beetle community dissimilarity increased with VOC dissimilarity, but only for forest floor VOCs. Our finding adds a new component to the framework of habitat heterogeneity, the invisible gradient of volatile diversity utilized by many forest organisms. Furthermore, we provide the first evidence that enhancing the heterogeneity of forests, and particularly of the dead wood, increase not only the structural heterogeneity but also the volatile {beta}-diversity.

ecology↗

bioRxiv2025

Forest vertical and horizontal temperature similarity drives arthropod communities in a managed temperate forest

Manipulating the canopy structure is the core tool of silviculture operation, and with that, changing the light availability alters temperature dynamics from the forest floor to the canopy. This should affect communities of ectothermic organisms such as insects, but we lack information on insect distributions in the complex 3D space of forests. Therefore, we set up temperature loggers and insect traps vertically (flight-interception traps) and horizontally (pitfall traps) in forests with experimental thinning and gap felling 8 years after the intervention. By metabarcoding, we identified [~]10,600 Operational Taxonomic Units (OTUs) from 44 orders including [~]2450 arthropods assigned to species in our 426 samples. Arthropod community similarity matrices were quantified along the Hill numbers accounting for rare to dominant species and under consideration of incomplete samples. Arthropod communities were shaped by stratification (height above ground 0 m, 2 m, 10 m, 15 m), and by temperature similarity. Average nighttime temperature was the most important temperature variable for overall arthropod community similarity metrics. Restricted to flight interception traps, flying insect communities responded to daily temperature maximum and nighttime average temperature. Restricted to pitfall traps, on the other hand, arthropod communities were shaped by the overall temperature metric only when focusing on rare species. Additionally, all communities were strongly affected by season. Our results implies that management interventions establish different temperature heterogeneity within forest patches, which ultimately could drive species community similarity when including all arthropods in the area between forest floor and canopy.

ecology↗

bioRxiv2025

Old growth attributes by chain saw: how between-patch heterogeneity changes the metacommunities of beetles in temperate forests

Metacommunity theory has expanded our understanding of how spatial dynamics and local interactions influence species communities. Different assembly archetypes, reflecting different roles of species differences, habitat differences, and dispersal have been described, but we lack empirical studies specifically in terrestrial habitats testing which archetype is most important. In a replicated design we experimentally enhanced structural between-patch heterogeneity in homogeneous production forests and developed a statistical framework controlling for sample incompleteness to detect different metacommunity processes. Meta-analyses on >100K individuals of >1.3K beetle species showed an increase of [~]60 species in heterogenized forests at {gamma}-level promoted by increasing -diversity consistent with the mass-effect and an increase of {beta}-diversity by [~]10% supporting species-sorting. Additionally, we tested {beta}-deviations from random assembly as a proxy of neutral processes. Findings indicate that enhancing structural heterogeneity can shift forests from patch-dynamics dominance towards mass-effect and species-sorting, offering a promising pathway to restore biodiversity in managed landscapes.

ecology↗

bioRxiv2025

Enhanced forest heterogeneity drives stronger functional than taxonomic shifts in soil nematodes

Production forests are often managed primarily for timber production, leading to biotic homogenization and reduced biodiversity. To explore strategies that promote biodiversity while maintaining timber yields, we conducted a large-scale experiment in eight German forests. We manipulated structural {beta}-complexity, i.e., the heterogeneity of structural elements across forest patches, by experimentally introducing variation in canopy gaps and different types of deadwood across 156 plots of 50 x 50 m each, to investigate its effects on forest biodiversity. We analyzed soil nematode communities, which are important bioindicators and contributors to ecosystem processes, by assessing taxonomic and functional diversity across patch (), site ({gamma}), and between-patch ({beta}) scales using Hill-Chao numbers. Additionally, we tested whether environmental variables explain nematode diversity responses. Our results show that functional diversity is more responsive than taxonomic diversity, with increased {beta}-diversity of common and frequent taxa alongside simultaneous declines in - and {gamma}-diversity. This pattern suggests a shift toward more specialized nematode communities in response to the intervention. Moreover, we found that site-specific conditions, such as sand content and understory biomass, modulated these effects. Overall, our findings reveal complex, scale-dependent responses of nematode diversity to aboveground forest structural changes, emphasizing the need to consider environmental context in forest biodiversity management. This study represents an important first step toward understanding and enhancing soil biodiversity at management-relevant spatial scales.

ecology↗

bioRxiv2025

Enhancing structural heterogeneity in managed forest landscapes promotes gamma but not beta diversity in understorey plant communities

O_LIAlthough habitat heterogeneity is known to enhance local species diversity, the effects of management-driven structural heterogeneity on understorey plant communities across spatial scales remain poorly understood, despite their crucial role for forest biodiversity and ecosystem functioning. C_LIO_LITo analyse how forest understorey plant communities respond to an enhancement of structural heterogeneity in managed forests, we established 11 experimental sites consisting of two paired forest landscapes, an untreated homogenous control and a treatment district (ESBC). In treatment districts, structural heterogeneity was enhanced through different combinations of local patch-scale manipulations of light and deadwood features, leading to greater between-patch heterogeneity at the landscape scale. We performed a meta-analysis across these 11 sites using a Hill-Chao number and sample coverage standardisation framework. C_LIO_LIGamma diversity increased across taxonomic, functional and phylogenetic facets in structurally heterogeneous forests (ESBC districts) via higher alpha diversity. This effect was positively associated with heterogeneity in light availability between forest patches, but not with their mean light availability. In contrast, we found no support that species turnover among patches (i.e., beta diversity) significantly contributes on average to the observed increase in gamma diversity. However, both the direction and magnitude of beta diversity responses varied substantially among landscapes. C_LIO_LIOn average, structurally heterogeneous forests supported higher species richness for both open and closed forest habitat species. C_LIO_LISynthesis and applications: Our findings highlight the benefits of enhancing structural heterogeneity for understorey plant diversity in managed forest landscapes. Specifically, management strategies that create a spatial mosaic of interventions, such as combining single-tree removal with group felling, can increase the variety of light niches among forest patches, thereby supporting the conservation of a wide range of understorey plant species, including forest specialists. C_LI

ecology↗

bioRxiv2025

Enhancing experimentally the structural heterogeneity of forests increase soil fungal diversity but functional lifestyles in contrasting ways

Fungal communities in soils are highly diverse both in species and functions forming a major backbone of forest ecosystems. Recent observational high-throughput-sequencing studies have shown that fungal diversity is correlated with resource availability and climate across different spatial scales. However, the underlying mechanisms remain poorly understood. Across Germany, we experimentally manipulated 11 typically homogeneous, broadleaf production forests to increase their between-patch-heterogeneity (ESBC) and compared them with a control forest. In specific, we enhanced light availability via canopy openness and deadwood resources in the ESBC treatments. Fungal communities were determined by metabarcoding at 234 patches and analysed using a novel meta-analytical approach for pairwise comparisons of taxonomic and phylogenetic diversity along Hill numbers. We hypothesized that {gamma}-diversity is primarily driven by {beta}-diversity increasing with canopy mediated microclimate variability and secondarily by -diversity increasing with resource availability. Furthermore, we expected an increase in {gamma}-diversity by unique phylogenetic lineages supporting the insurance hypothesis. Our results showed a significant increase in {gamma}-diversity in ESBC forests, first by - and second by {beta}-diversity, both of which were influenced mainly by microclimate and not resource availability. The increase of phylogenetic diversity with ESBC was weak indicating functional similarity of species. Analysis of symbiotic, saprotrophic and parasitic fungal assemblages revealed contrasting effects of resource availability and microclimate across the scales. As in the UN Decade of Ecosystem Restoration many forest managers aim to increase the heterogeneity of forests and are simultaneously face rising tree mortality, our study provides first robust empirical evidence for the varying effects of forest gaps and deadwood on fungal diversity across -, {beta}-, {gamma}-scales for this major kingdom.

ecology↗