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Emerald ash borer (EAB) has killed millions of ash trees in the United States and Canada, yet impacts on terrestrial- aquatic linkages are largely unknown. Ash tree death along streams creates canopy gaps, increasing light to riparian plants and potentially affecting organic matter subsidies. Six EAB-related canopy gaps along streams across a gradient of timing of EAB invasion in Michigan were characterized for coarse woody material (CWM), terrestrial and aquatic leaf litter and their associated bacterial communities, and macroinvertebrates upstream, downstream, and at the center of the gap. Stream sites downstream of EAB-related canopy gaps had significantly lower dissolved oxygen and macroinvertebrate diversity than sites upstream and at the gaps. Yet there was no difference in CWM or aquatic leaf litter, likely due to downstream movement of organic matter from upstream riparian sources. Low abundance bacterial amplicon sequence variants unique to gap or forest were detected in leaves and leaf litter, suggesting that EAB-related canopy gaps altered leaf-associated bacterial communities. Overall, EAB invasion indirectly impacted some variables, while organic matter dynamics were resistant to change. Key words: Emerald ash borer, terrestrial-aquatic linkages, leaf litter, aquatic communities, Introduction Invasive species are a critical natural resource concern, due to their environmental and economic repercussions (Vitousek et al. 1997; McGeoch and Jetz 2019). Forest invasive species cause an array [...]

Silphinae (Staphylinidae; carrion beetles) are important contributors to the efficient decomposition and recycling of carrion necromass. Their community composition is important for the provision of this ecosystem function and can be affected by abiotic and biotic factors. However, investigations are lacking on the effects of carrion characteristics on Silphinae diversity. Carrion body mass may affect Silphinae diversity following the more individuals hypothesis (MIH). The MIH predicts a higher number of species at larger carrion because higher numbers of individuals can be supported on the resource patch. Additionally, biotic factors like carrion species identity or decomposition stage, and the abiotic factors elevation, season and temperature could affect Silphinae diversity. To test the hypotheses, we collected Silphinae throughout the decomposition of 100 carcasses representing 10 mammal species ranging from 0.04 to 124 kg. Experimental carcasses were exposed in a mountain forest landscape in Germany during spring and summer of 2021. We analysed Silphinae diversity using recently developed transformation models that considered the difficult data distribution we obtained. We found no consistent effect of carrion body mass on Silphinae species richness and, therefore, rejected the MIH. Carrion decomposition stage, in contrast, strongly influenced Silphinae diversity. Abundance and species richness increased with the decomposition process. Silphinae abundance increased with temperature and decreased with elevation. Furthermore, Silphinae abundance was lower in summer compared to spring, likely due to increased co‐occurrence and competition with dipteran larvae in summer. Neither carrion species identity nor any abiotic factor affected Silphinae species richness following a pattern consistent throughout the seasons. Our approach combining a broad study design with an improved method for data analysis, transformation models, revealed new insights into mechanisms driving carrion beetle diversity during carrion decomposition. Overall, our study illustrates the complexity and multifactorial nature of biotic and abiotic factors affecting diversity. [ABSTRACT FROM AUTHOR]

Ephemeral resource patches (ERPs) – short lived resources including dung, carrion, temporary pools, rotting vegetation, decaying wood, and fungi – are found throughout every ecosystem. Their short‐lived dynamics greatly enhance ecosystem heterogeneity and have shaped the evolutionary trajectories of a wide range of organisms – from bacteria to insects and amphibians. Despite this, there has been no attempt to distinguish ERPs clearly from other resource types, to identify their shared spatiotemporal characteristics, or to articulate their broad ecological and evolutionary influences on biotic communities. Here, we define ERPs as any distinct consumable resources which (i) are homogeneous (genetically, chemically, or structurally) relative to the surrounding matrix, (ii) host a discrete multitrophic community consisting of species that cannot replicate solely in any of the surrounding matrix, and (iii) cannot maintain a balance between depletion and renewal, which in turn, prevents multiple generations of consumers/users or reaching a community equilibrium. We outline the wide range of ERPs that fit these criteria, propose 12 spatiotemporal characteristics along which ERPs can vary, and synthesise a large body of literature that relates ERP dynamics to ecological and evolutionary theory. We draw this knowledge together and present a new unifying conceptual framework that incorporates how ERPs have shaped the adaptive trajectories of organisms, the structure of ecosystems, and how they can be integrated into biodiversity management and conservation. Future research should focus on how inter‐ and intra‐resource variation occurs in nature – with a particular focus on resource × environment × genotype interactions. This will likely reveal novel adaptive strategies, aid the development of new eco‐evolutionary theory, and greatly improve our understanding of the form and function of organisms and ecosystems. [ABSTRACT FROM AUTHOR]