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Despite their ecological significance, non‐vascular photoautotrophs (NVPs) are frequently excluded from ecological experimental studies, leading to a limited comprehension of how their communities are affected by the ecosystem dynamics and an underestimation of their role in ecosystem functioning. We studied the impact of vascular plant taxonomic and functional diversity on three groups of ground NVPs (lichens, bryophytes, and cyanobacteria) within one of the longest‐running plant biodiversity experiments (Biodiversity and Ecosystem Function at Cedar Creek Ecosystem Science Reserve). Utilizing the permanent plot framework of this experiment, we analyzed the effects of almost 30 years of treatment across various levels of vascular plant taxonomic and functional diversity on NVPs. For each diversity level we documented NVP cover and richness. Using generalized linear models we evaluated the effect of vascular plant taxonomic and functional diversity, as well as environmental factors affected by vascular diversity (such as vascular plant cover, light penetration, soil nutrient content, and microtopography) on NVP richness and cover. Using these models, we conducted structural equation modeling analyses (SEM) that allowed us to differentiate the direct and indirect impacts of vascular plant taxonomic and functional diversity on NVPs. Our results showed that both lichen and bryophyte richness and cover decreased with higher vascular plant taxonomic and functional diversity, while cyanobacteria cover increased as a function of the same parameters. We also showed that microtopography serves as better predictor for lichens and bryophytes, while nutrient‐related factors perform better as predictors for cyanobacteria. Additionally, our findings indicate that NVP cover ranged from 0.001% to 100% (mean 15%) in the surveyed plots, representing a major, still ignored, component of the experimental plots. This study shows that vascular plant diversity directly and indirectly affects NVP communities, but the consequences of these effects at community and ecosystem levels are still to be explored. [ABSTRACT FROM AUTHOR]

Abstract: Parasitic infections are increasingly recognized as influential forces in the migratory behaviors of hosts ranging from butterflies to whales. In aquatic zooplankton, diel vertical migrations (DVMs) are among the most recurrent behaviors with implications for predator‐prey interactions, nutrient cycling, and energy flow, yet how parasitism affects such migrations remains an open question. Here, we tested the effects of sporangia cluster disease (SCD) on DVM of the large‐bodied Daphnia pulicaria, which is often considered a key component of lake food webs. By collecting depth‐specific zooplankton samples across diel cycles, between years, and among lakes, we show that infection is associated with strong inhibition of host DVM; while all Daphnia tended to occur deeper during the day, uninfected Daphnia and especially gravid individuals migrated to shallower waters at night. In contrast, infected hosts—which could comprise 40% of the population—were more likely to remain deep regardless of time of day. Among infected hosts, the intensity of SCD (sporangia count per host) predicted the degree of DVM inhibition. These observations—coupled with lab‐based assays showing that infected hosts exhibited fewer swimming movements and persisted at lower depths than uninfected conspecifics—suggest that parasite‐induced inhibition of DVM is a “sickness behavior” resulting from increasing morbidity and energy depletion as the infection intensifies toward host death. Considering the importance of large‐bodied Daphnia as regulators of water clarity and prey for fishes, parasite‐induced alterations of host migratory behavior have broad potential to affect the redistribution of energy and nutrients within lake ecosystems. [ABSTRACT FROM AUTHOR]

A core vulnerability in symbioses is the need for coordination between the symbiotic partners, which are often assumed to be closely physiologically integrated. We critically re-examine this assumed integration between symbionts in lichen symbioses, recovering a long overlooked yet fundamental physiological asymmetry in carbon balance. We examine the physiological, ecological, and transcriptional basis of this asymmetry in the lichen Evernia mesomorpha . This carbon balance asymmetry depends on hydration source and aligns with climatic range limits. Differences in gene expression across the E. mesomorpha symbiosis suggest that the physiologies of the primary lichen symbionts are decoupled. Furthermore, we use gas exchange data to show that asymmetries in carbon balance are widespread and common across evolutionarily disparate lichen associations. Using carbon balance asymmetry as an example, we provide evidence for the wide-ranging importance of physiological asymmetries in symbioses.