Trophic niche variation in springtails across soil depth

Soil invertebrates move vertically to forage and avoid environmental stress. However, how invertebrates change their diet with depth is poorly understood, limiting our understanding of the trophic plasticity of soil invertebrates. Trophic consistency may be due to the existence of similar trophic niches at the microscale across soil layers (‘micro-scale feeding hypothesis’), but also due to feeding at certain depth despite moving between layers. To examine these alternatives, we conducted a microcosm experiment incubating springtails (Ceratophysella denticulata) in six separate forest soil layers (L, F/H, 0–3, 3–6, 6–9 and 9–12 cm depth of the mineral soil) and analyzed changes in Collembola stable isotope ratios (13C/12C, 15N/14N). As expected, 13C/12C and 15N/14N ratios in litter and soil organic matter increased with depth, whereas 13C/12C ratios of Collembola did not significantly differ across layers suggesting consistent basal resource use supporting the micro-scale feeding hypoth..., Soil cores (ø 5 cm) were taken in a beech forest in Dassel on October 18, 2022. Soils were separated into six depths: L-layer (litter; depth ~ 3 cm), F/H-layer (3 cm, fragmented litter and humus material), 0–3 cm, 3–6 cm, 6–9 cm, and 9–12 cm soil depth (Ah-layer). The soil texture was silt loam (clay 21%, silt 53%, and sand 26%). Samples were stored at -20°C for two weeks, and then freeze-dried for defaunation. Water was added to adjust moisture content to the level at sampling. Soil animals were inoculated by using 1-6-day old juveniles of Ceratophysella denticulata. After incubating for four weeks in 20°C for 4 weeks, bulk stable isotopes of litter and soil were measured after drying at 60°C and grinding samples in a ball mill (Retsch, MM200). Collembolans were extracted from the litter/soil using heat, kept in 50% diethylene glycol, and then transferred into 70% ethanol for storage. As the available dry weight of collembolans was smaller than 100 µg, the bulk stable isotope ratios of..., , # Data from: Trophic niches of springtail across soil depth in a lab microcosm experiment

[https://doi.org/10.5061/dryad.m37pvmd8s](https://doi.org/10.5061/dryad.m37pvmd8s)

This dataset includes results of a lab experiment testing the effects of depth on trophic niche of soil collembolans using bulk stable isotope analysis.

## Description of the data and file structure

The dataset \"data.for.Dryad_copy.csv\" includes C, N, and stable isotopic C and N ratios of soil from six layers, as well as isotopic ratios of collembolans that have incubated in each separated soil layers.

* Sample: unique identifier of each microcosm
* id_block: each of the five replicate block
* id_depth: each of the six depths: litter, F/H, 0-3, 3-6, 6-9, 9-12 (coded in A-F)
* animal_nr: number of collembolan individuals used for stable isotope analysis
* Weight_animal_mg: animal dry biomass (mg) used for bulk stable isotope analysis
* delta_15N.animal: delta 15N of Collembola
* delta_13C.animal: delta 13C of Col...,