Data from: Effects of two key plant trait spectra on litter layer properties and habitat provision functions
Abstract
Plant litter harbours a wide range of organisms, such as soil animals, microbes, vascular plants (including their seeds and seedlings), mosses, and lichens. While it is well-recognised that litter drives carbon and nutrient cycling through their traits related to the plant resource economics spectrum (PES), their explanatory power for predicting the litter-dwelling biological community has been very low. In this era of biodiversity change, litter habitat provisioning functions for myriad organisms should receive more research attention.
A conceptual multivariate trait space defined by a physical trait axis related to the litter size and shape spectrum (SSS) and a biochemical trait axis (PES) has been proposed to explain habitat as well as nutrition functions for soil organisms. We aim to improve the explanatory power of litter traits for the litter-dwelling animal communities by testing this concept, and by connecting fundamental traits related to size and shape of single litter particles (i.e., leaf litter units) with litter and litter layer properties more directly related to habitat quality (e.g., moisture regime, habitat space).
We tested the concept by using 16 woody species commonly observed in NW Europe, and examined how different traits or trait axes determine the litter and litter layer properties directly related to habitat quality for soil animals. In addition, we assessed in a field experiment with litter layers in mesocosms how this new trait framework explains the soil invertebrate community as an actual example of linking litter traits and host function to other organisms.
The two plant trait spectra together accounted for > 60% of the variance in litter quality in a principal component analysis. SSS-related traits strongly explained litter layer habitat-related properties, such as water-holding capacity and litter bulk density. The SSS axis and these SSS-associated properties more strongly determined soil animal communities assembled over seven weeks in the field experiment, surpassing the effects of the PES axis.
Synthesis. This study has provided the first empirical evidence for the litter trait space defined by both SSS and PES spectra occupied by wide-ranging plant species, and its utility to explain litter layer properties related to the physical environment and associated habitat provisioning function. We suggest that this trait-based SSS-PES framework will help us to disentangle mechanisms underpinning real-world interactions between aboveground vegetation and belowground communities.
Dataset DOI: 10.5061/dryad.76hdr7t74
Description of the data and file structure
litter_variables sheet
The data sheet of litter variables includes all litter variables, including litter traits, single litter and litter pack properties, of the plant species we used in the study.
Chemical traits include
- nitrogen content (% of dry mass),
- phosphorus content (% of dry mass),
- tannin content (% of dry mass),
- lignin content (mg g-1),
- carbon-to-nitrogen ratio (C:N), and
- pH.
Physical traits include
- leaf area (cm2),
- leaf volume (cm3),
- leaf thickness (mm),
- leaf curliness (mm),
- specific leaf area (SLA, cm2 g-1),
- leaf tissue density (LTD, mg cm-3),
- leaf dry matter content (LDMC, mg g-1),
- leaf dissection index (DI), and
- petiole width (mm).
PC1 and PC2 are the first and second axis of a principal component analysis (PCA) using these chemical and physical traits of single litter particles.
Single litter and litter pack properties include litter drying rate (LDR) after water saturation, change in curliness with drying after water saturation (mm), litter bulk density (g cm-3), LDR of litter pack after water saturation and change in litter bulk density with drying after water saturation (g cm-3).
Abbreviations of single litter and litter pack properties are as follows:
- LDR_litter = litter drying rate of single litter particle,
- LDR_litterpack = litter drying rate of litter pack,
- Curliness_temp = temporal variability in curliness,
- Litter_density = litter bulk density,
- Litter_density_temp = temporal variability in litter bulk density.
- Species ID is an abbreviation of each woody species name.
community_data sheet
The data sheet of community data includes abundance data of each soil animal taxon, the total abundance of all taxa, mesofauna and macrofauna, and taxa richness of each container in the litter incubation experiment. Macrofauna taxa includes Araneae, Chilopoda, Coleoptera, Coleoptera larvae, Diplopoda, Diptera larvae, Hemiptera, Isopoda, Lepidoptera larvae and Opiliones, while mesofauna includes Astigmata, Collembola, Mesostigmata, Oribatida, Prostigmata and Pseudoscorpiones. Core_area means each container size (cm2) incorporated as an offset term in generalised linear mixed model (GLMM). Species ID is generally just an abbreviation of each woody species name, but there are exeptions: LCB = C. betulus in large-size containers (see SI. 2), SCB = C. betulus in small-size containers, LTD = *T. distichum *in large-size containers, and STD = *T. distichum *in small-size containers.
SI1_curliness and SI1_litter_bulk_density sheets
The data sheets of SI1_curliness and SI1_litter_bulk_density include the raw data for the figures in the support information, which describe the change in curliness (after 0, 0.5, 1, 2, 4, 6 and 8 h) and litter bulk density of litter packs (0, 3, 6, 9, 27, 51 and 75 h) after water saturation. Species are shown in abbreviations of woody species names. Rep shows replications in each data set. Type shows AD (Angiosperm Deciduous), AE (Angiosperm Evergreen), GD (Gymnosperm Deciduous) and GE (Gymnosperm Evergreen).