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Climate change-induced windfalls and droughts exacerbate bark beetle outbreaks, severely impacting forest ecosystems. Despite extensive research on bark beetle infestation patterns, the question regarding the optimal spatial grid (SG) size for analyzing this phenomenon remains unresolved. The protective potential of natural forest complexity against bark beetles has been underestimated. We used remotely sensed data to fit Generalized Linear Models and structural equation models to explore the direct and environment-mediated effects of mixed forest cover (MFC) on Norway spruce forest infestation in central Europe. We assessed the effectiveness of various spatial grids (from 100 m to 1 km) for studying infestation by Ips typographus. We found a strong non-linear decline in infestation with increasing MFC across different spatial scales. The relationship between infestation and temperature was positive, while elevation had a negative effect on infestation, with higher infestation rates observed below 900 m. Direct effects of environmental predictors on infestation were significant at SGs of 100 m, 300 m, 400 m, and 500 m, but insignificant at 200 m and 1000 m SGs. Slope positively influenced infestation at 300 m and 400 m SGs. MFC exhibited significant indirect effects on infestation mediated by elevation, temperature, potential evapotranspiration, slope, and heat load index. Landscape variables played a significant role in the models at high-resolution spatial grids, whereas climate variables were influential in models at lower spatial grids of infestation data. We argue that mixed forest facilitates cooling, preserves water, enriches symbiotic fungal community, alleviating tree drought stress and mitigating infestation risk. Broad-leave trees' non-host volatiles presumably disrupt olfactory signals, impeding beetles' ability to locate host trees effectively. Our results underscore the potential of increasing mixed forest cover as a self-sustainable silvicultural measure for forest protection against I. typographus and for mitigating the effects of climate change. • Mixed forest cover has a direct negative effect on beetle infestation in forests. • Selected env. predictors, mediate negative effects of mixed forest on infestation. • Elevation and temperature are the prime drivers of infestation patterns in forests. • Lower elevation and higher temperature increase susceptibility to infestation. • The relationships between infestation and env. predictors are scale dependent. [ABSTRACT FROM AUTHOR]

Scope: This multi-omic study investigates the bidirectional interactions between gut microbiota and silymarin metabolism, highlighting the differential effects across various age groups. Silymarin, the extract from Silybum marianum (milk thistle), is commonly used for its hepatoprotective effects., Methods and Results: An in vitro fermentation colon model was used with microbiota from 20 stool samples obtained from healthy donors divided into two age groups. A combination of three analytical advanced techniques, namely proton nuclear magnetic resonance ( 1 H NMR), next-generation sequencing (NGS), and liquid chromatography-mass spectrometry (LC-MS) was used to determine silymarin microbial metabolites over 24 h, overall metabolome, and microbiota composition. Silymarin at a low diet-relevant dose of 50 µg mL -1 significantly altered gut microbiota metabolism, reducing short-chain fatty acid (acetate, butyrate, propionate) production, glucose utilization, and increasing alpha-diversity. Notably, the study reveals age-related differences in silymarin catabolism. Healthy elderly donors (70-80 years) exhibited a significant increase in a specific catabolite associated with Oscillibacter sp., whereas healthy young donors (12-45 years) showed a faster breakdown of silymarin components, particularly isosilybin B, which is associated with higher abundance of Faecalibacterium and Erysipelotrichaceae UCG-003., Conclusion: This study provides insights into microbiome functionality in metabolizing dietary flavonolignans, highlighting implications for age-specific nutritional strategies, and advancing our understanding of dietary (poly)phenol metabolism., (© 2024 The Author(s). Molecular Nutrition & Food Research published by Wiley‐VCH GmbH.)