Remmers, S. | bioRxiv Science

bioRxiv2026

Respirometry dataset for oxygen consumption measurements in carabid beetles

OverviewThis dataset originates from a preliminary respirometry study on carabid beetles from the Elbe Estuary (Northern Germany), encompassing species from freshwater and saltmarsh habitats along a salinity gradient. The study was designed to establish and validate a workflow for measuring oxygen consumption, including chamber setup, sensor recording, drift correction, and calculation of absolute and mass-specific metabolic rates. Oxygen consumption was measured for five species (Carabus auratus, Carabus granulatus, Limodromus assimilis, Poecilus versicolor and Pterostichus niger) using sealed glass vials connected to an optical oxygen system. The dataset provides individual-level measurements and serves primarily as a methodological reference for future respirometry studies on ground-dwelling arthropods. The O2 consumption rates of carabid beetles showed interspecific differences and followed metabolic scaling theory, revealing an inverse relationship between body mass and mass-specific metabolic rates across species (Figure 3). O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=127 SRC="FIGDIR/small/720111v1_fig3.gif" ALT="Figure 3"> View larger version (17K): org.highwire.dtl.DTLVardef@e0bc7eorg.highwire.dtl.DTLVardef@771dadorg.highwire.dtl.DTLVardef@3d7327org.highwire.dtl.DTLVardef@530ab1_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure 3:C_FLOATNO Oxygen consumption rates of Carabid species per (a) animal in [ml O2 h-1] and as (b) mass-specific consumption rate [ml O2 h-1 g-1]. Points represent mean oxygen consumption per individual (C. auratus: n = 2; L. assimilis: n = 6; P. versicolor: n = 7; P. niger: n = 6). C_FIG

physiology↗

bioRxiv2025

Diversity and Functional Roles of Carabid Beetles across Salinity Gradients in Marshlands

Marsh ecosystems represent ecotones of high ecological significance where terrestrial and aquatic systems converge, governed by strong gradients in salinity and flooding. These environments sustain specialised communities and perform vital ecosystem functions such as carbon sequestration or nutrient cycling. This study examined carabid beetle (Coleoptera: Carabidae) assemblages across freshwater and saltwater marshes along the Elbe estuary in northern Germany to assess how environmental conditions shape patterns of abundance, diversity, and functional traits. Over 17,000 individuals representing 84 species were collected between March and October 2024. Despite similar species richness between marsh types, community composition differed markedly (Bray-Curtis dissimilarity: 0.92), reflecting environmental filtering along the salinity gradient. Freshwater marshes exhibited greater overall functional richness, while saltwater marshes supported more functionally even and divergent trait distributions, indicating stronger niche specialization under saline stress. Seasonal activity was bimodal in both habitats but peaked earlier in freshwater sites. A generalized linear mixed model revealed significant positive relationships between carabid activity abundance and functional richness of both dispersal- and preference-based traits. These findings demonstrate that salinity and flooding regimes drive distinct taxonomic and functional assemblages, with trait diversity underpinning ecosystem resilience and functioning. The study establishes an ecological baseline for future monitoring of marshland biodiversity and highlights the necessity of conserving functionally diverse communities to maintain the ecological integrity of tidal and floodplain marshes under changing environmental conditions.

ecology↗