Data in: Reduced predation and energy flux in soil food webs by introduced tree species

The introduction of non-native tree species has become a global concern and may disrupt native communities and related ecosystem functions. Soil food webs regulate organic matter decomposition and nutrient cycling in forests with their feeding activities, but evaluating the consequences of tree species introduction on soil invertebrates is challenging due to the complex trophic structure and wide range in body size of soil invertebrates. Here, we employed an energetic food web approach and estimated the energy flux in soil food webs using a four-node model including soil meso- and macrofauna decomposers and predators. We examined pure and mixed stands of native European beech (Fagus sylvatica), introduced Douglas fir (Pseudotsuga menziesii), and native range-expanding Norway spruce (Picea abies) across site conditions. Compared to native forests, introduced tree species reduced the total mass of macrofauna predators by 92% at sandy sites but not that of decomposers, suggesting trophic d..., Soil samples were taken to evaluate the population density of soil meso- and macrofauna between November 2017 and January 2018. At an equidistance from trees of the same (pure stands) or different species (mixed stands), two small (⌀ 5 cm) and two large (⌀ 20 cm) soil cores were taken at a distance of approximately 10 m close to the center of each plot. Soil cores were separated into litter (OL/F), 0–5 cm, and 5–10 cm depth and transported to the laboratory for extraction of soil meso- and macrofauna using heat. Mesofauna (Acari, Collembola, Diplura, Pauropoda, Protura, Symphyla) were extracted from small cores, and Pseudoscorpionida and macrofauna were extracted from large cores. The extracted animals were collected in 50% diethylene glycol and then transferred into 70% ethanol for determination.
Animal taxa were first sorted and assigned into functional groups. Adults of soil microarthropods (Collembola, Mesostigmata, and Oribatida) were identified to species level, and other soil inv..., , # Data in Reduced predation and energy flux in soil food webs by introduced tree species

[https://doi.org/10.5061/dryad.7sqv9s52c](https://doi.org/10.5061/dryad.7sqv9s52c)

## Description of the data and file structure

The data include fresh mass, energy flux, and local biodiversity of soil mesofauna (decomposer, predator) and macrofauna (decomposer, predator).  

### Files and variables

#### File: \_Lu2024-Biomass_and_energy_flux_in_temperate_forests.csv

**Description:** 

##### Variables

* id_forest: 1 to 5 coding for forest type (Douglas, Douglas-Beech, Beech, Spruce-Beech, Spruce)
* id_quintet: one of the eight study sites (1-8)
* Q_groups: quintet groups, Q1-4 (loamy sites), Q5-8 (sandy sites)
* mass_macrodecomposer: fresh mass in ug m-2 of macrofauna decomposer
* mass_mesodecomposer: fresh mass in ug  m-2
* mass_macropredator: fresh mass in ug  m-2
* mass_mesopredator: fresh mass in ug  m-2
* mass_total: fresh mass in ug m-2
* flux_macrodecomposer: energy flux in Joule m-2 h-...,