Loading...
Photo shows an earthworm and a horn mite on the forest floor

Soil food webs are an essential part of terrestrial ecosystems and closely linked to aboveground systems. In soil, animals act as decomposer of dead organic matter, as root feeders or as ecosystem engineers, which improve soil structure by mixing soil layers. Despite their important role, we know little about these creatures and their interactions due to their small size, high diversity, but also their cryptic life.


We investigate the effect of forest land use on the structure of and trophic interactions in soil animal communities. The goals of this project are two-fold: First, we characterise the animal communities of the soil and litter layer in differently managed forests and record shifts in abundance, diversity and biomass over time. We then use these data to study trophic relationships of key species, their trophic position and food resources.


We are examining inter-annual shifts in soil animal communities. Species fluctuate between years due to changing abiotic (temperature, precipitation) and biotic factors (changes in competitive interactions, predation or facilitation).

Hypotheses

  • Generally, dominance and trophic structure in the soil animal communities vary little in time, and variations with forest type / land-use intensity are consistent in time.
  • Temporal variations are more pronounced in larger soil animal taxa and increase with trophic level.

Methods

Soil Macrofauna (Fig.1) and Mesofauna (Fig.2) will be extracted from litter and soil separately using the high gradient canister technique (Fig. 3A). Earthworms will be extracted by the mustard method. Soil animals will be identified to species level and abundance, diversity and biomass will be recorded.
Information on microorganisms is essential for the analysis of trophic links in soil animal food webs.

Therefore, microbial biomass will be measured by substrate-induced respiration (SIR) and microbial phospholipid fatty acid (PLFA) patterns using biomarker fatty acids.



We aim to follow energy fluxes from basal resources, such as fungi, bacteria and plants, through the decomposer food web up to predators, thereby uncovering differences in energy fluxes with management intensity and forest type. We will analyse major groups of meso- and macrofauna at community level, including Collembola, Oribatida, Gamasida, Lumbricida, Diplopoda/Isopoda and Araneida.

Hypotheses

  • Energy fluxes vary little between differently managed beech forests, but differ between deciduous (beech) and coniferous forests; this pattern is consistent in time.
  • Energy is channeled in similar ways through meso- and macrofauna, reflecting food web compartmentalisation; patterns are similar in beech forests of different age, but differ between beech and coniferous forests.

Methods

As δ13C signatures in amino acids differ between bacteria, fungi and plants due to different biosynthetic pathways, a fingerprinting approach using δ13C values of essential amino acids can differentiate basal resources in consumers. The relative consumption of these resources can be quantified using mixing models. The trophic position of consumers can be calculated using δ15N values of so-called ‘trophic’ and ‘source’ amino acids; the former are strongly enriched with each trophic transfer, whereas the latter are not or only slightly enriched, reflecting the isotopic signature of the basal resource. The trophic position can be calculated from the isotopic difference between these amino acids more accurately than by using bulk isotopic signatures.

Compound-specific analysis of δ13C in marker fatty acids for bacteria, fungi and plants can also provide information on energy fluxes from different basal resources to consumers, thereby complementing compound-specific analysis of amino acids.


The aim of this project is to analyse the response of decomposer communities and the soil food web to forest gap formation as strong disturbance and the presence of deadwood which provides additional niches for the decomposer community. The approach opens the perspective for understanding the stability and long-term recovery of major functions of soil animal communities as well as the recovery of soil animal communities at species level after strong disturbances.

Hypotheses

  • The response of soil animal communities to forest gap formation varies between functional groups of soil invertebrates and is most pronounced in detritivores (rather than predators).
  • The response of soil animal communities to forest gap formation varies with forest type / land-use intensity and is most pronounced in forest ecosystems of low management intensity, i.e. increases from natural to mature to young beech to coniferous forests.

Methods

Following the design of the common ‘Forest Gap Experiment’ (FOX) four types of experimental plots will be established within different forest types: undisturbed dense forest, dense forest with deadwood on the forest floor, forest gap with deadwood on the forest floor, and forest gap without deadwood. In each of the experimental plots the soil fauna (Figs 1 & 2) will be extracted from litter and soil using a high gradient canister technique (Fig. 3) and diversity, abundance and biomass will be measured. Earthworms will be extracted by the mustard method and microbial biomass will be measured by the substrate-induced respiration (SIR).

Fig. 3. Sampling methods to extract soil animals. High gradient canister technique for soil samples.

Our project LitterLinks examines the community composition and trophic structure of soil animals, and their microbial resources as related to variations in environmental factors, including forest types and land-use intensity.

  • We showed that species composition, abundance and biomass of soil animal communities are strongly influenced by abiotic factors such as soil pH or climatic conditions (Bluhm et al., 2016; Pollierer & Scheu, 2017), pointing to the importance of regional environmental conditions, while soil animal communities are surprisingly resistant against changes in forest land-use intensity (Pollierer et al., 2021).
  • Using a comprehensive toolbox of methods, such as bulk stable isotope analyses (Erdmann et al., 2012; Klarner et al., 2017), fatty acid analyses (Ferlian & Scheu, 2014; Ferlian et al., 2015), molecular gut content analyses (Günther et al., 2014) and compound-specific isotope analyses of amino acids (Pollierer & Scheu, 2021), we showed changes in energy fluxes from basal resources to animal consumers in different forest types at the level of species.
  • Energy fluxes through microbial channels were more pronounced in coniferous compared to beech forests, with most mesofauna species feeding on saprotrophic and not ectomycorrhizal fungi (but see Bluhm et al., 2019). However, despite variations in leaf litter and microbial community composition (Pollierer et al., 2015), trophic niches of soil animal species were consistent across different forest types, presumably due to feeding at specific microsites (Ferlian et al., 2012; Pollierer & Scheu, 2021).
  • Deprivation of root-derived resources in a trenching experiment heavily decreased microbial biomass as well as abundance and biomass of soil animals, in particular mesofauna, indicating their major role in fuelling soil webs (Bluhm et al., 2019; 2021). However, only minor changes in community composition of soil microbes and animals suggest non-specific links to root-derived resources.

For references see ‘Publications’.


Doc
Bluhm S. L., Eitzinger B., Bluhm C., Ferlian O., Heidemann K., Ciobanu M., Maraun M., Scheu S. (2021): The Impact of Root-Derived Resources on Forest Soil Invertebrates Depends on Body Size and Trophic Position. Frontiers in Forests and Global Change 4:622370. doi: 10.3389/ffgc.2021.622370
More information:  doi.org
Doc
Die Reduktion von wurzelbürtigem Energiefluss beeinflusst die mikrobielle Biomasse nicht aber die Gemeinschaft
Bluhm S. L., Eitzinger B., Ferlian O., Bluhm C., Schröter K., Pena R., Maraun M., Scheu S. (2019): Deprivation of root-derived resources affects microbial biomass but not community structure in litter and soil. PLoS ONE 14 (3): e0214233. doi: 10.1371/journal.pone.0214233
More information:  doi.org
Doc
Beintaster (Protura) sind einzigartig: Erste Hinweise auf eine spezielle Ernährung mit Ektomykorrhizen bei Bodenarthropoden
Bluhm S. L., Potapov A. M., Shrubovych J., Ammerschubert S., Polle A., Scheu S. (2019): Protura are unique: first evidence of specialized feeding on ectomycorrhizal fungi in soil invertebrates. BMC Ecology 19:10. doi: 10.1186/s12898-019-0227-y
More information:  doi.org
Doc
Molekulare Analyse der Ernährung von Hundertfüssern (Chilopoda)
Eitzinger B. (2013): Molecular analysis of centipede predation. Dissertation, University of Goettingen
More information:  ediss.uni-goettingen.de
Doc
Bodennahrungsnetze sichtbar machen: Neue PCR Testverfahren zur Bestimmung von Beute-DNA im Darminhalt von räuberischen Gliederfüßern der Bodenschicht
Eitzinger B., Micic A., Körner M., Traugott M., Scheu S. (2013): Unveiling soil food web links: New PCR assays for detection of prey DNA in the gut of soil arthropod predators. Soil Biology and Biochemistry 57 (943–945). doi: 10.1016/j.soilbio.2012.09.001
More information:  doi.org
Doc
Einsatz von molekularer Darminhaltsanalyse zur Überprüfung der Eignung von Functional Response Modelle zur Vorhersage von Räuber-Beute-Interaktionen bei bodenlebenden Gliederfüßern
Eitzinger B., Rall B. C., Traugott M., Scheu S. (2018): Testing the validity of functional response models using molecular gut content analysis for prey choice in soil predators. Oikos 127 (7), 915-926. doi: 10.1111/oik.04885
More information:  doi.org
Doc
Auswirkungen von Beutequalität und Räuberkörpergröße auf Beute-DNA-Detektionserfolg in Hundertfüssern
Eitzinger B., Unger E. M., Traugott M., Scheu S. (2014): Effects of prey quality and predator body size on prey DNA detection success in a centipede predator. Molecular Ecology 23 (15), 3767–377. doi: 10.1111/mec.12654
More information:  doi.org
Doc
Analysing trophic interactions in centipedes (Chilopoda, Myriapoda) using fatty acid patterns: effects of life stage,forest type and season
Ferlian O. (2011): Analysing trophic interactions in centipedes (Chilopoda, Myriapoda) using fatty acid patterns: effects of life stage,forest type and season. Thesis, University Göttingen
Doc
Ferlian O. (2014): Soil animal food webs in temperate forests: effects of forest management on trophic structure as indicated by molecular gut content, stable isotope and fatty acid analyses. Dissertation, University Goettingen
More information:  ediss.uni-goettingen.de
Doc
Nahrungsressourcen von verschiedenen Regenwurm-Arten anhand von komponenten-spezifischen Stabile-Isotopen-Analysen
Ferlian O., Cesarz S., Marhan S., Scheu S. (2014): Carbon food resources of earthworms of different ecological groups as indicated by 13C compound-specific stable isotope analysis. Soil Biology and Biochemistry 77, 22–30. doi: 10.1016/j.soilbio.2014.06.002
More information:  doi.org
Doc
Unterschiede in Nahrungsressourcen bei Springschwänzen anhand von Fettsäure- und Stabile-Isotopen-Analysen
Ferlian O., Klarner B., Langeneckert A. E., Scheu S. (2015): Trophic niche differentiation and utilisation of food resources in collembolans based on complementary analyses of fatty acids and stable isotopes. Soil Biology and Biochemistry 82, 28–35. doi: 10.1016/j.soilbio.2014.12.012
More information:  doi.org
Doc
Verschiebung von Nahrungsspektren räuberischer Bodentiere mit Waldnutzungstypen anhand von Fettsäure- und Stabile-Isotopen-Analysen
Ferlian O., Scheu S. (2014): Shifts in trophic interactions with forest type in soil generalist predators as indicated by complementary analyses of fatty acids and stable isotopes. Oikos 123 (10), 1182–1191. doi: 10.1111/j.1600-0706.2013.00848.x
More information:  doi.org
Doc
Nahrungsbeziehungen von Hundertfüßern anhand von Fettsäureanalysen: Unterschiede mit Individualentwicklung, Waldalter und Jahreszeit
Ferlian O., Scheu S., Pollierer M. M. (2012): Trophic interactions in centipedes (Chilopoda, Myriapoda) as indicated by fatty acid patterns: Variations with life stage, forest age and season. Soil Biology and Biochemistry 52, 33–42. doi: 10.1016/j.soilbio.2012.04.018
More information:  doi.org
Doc
Gong X., Chen T.-W., Zieger S. L., Bluhm C., Heidemann K., Schaefer I., Maraun M., Liu M., Scheu S. (2018): Phylogenetic and trophic determinants of gut microbiota in soil oribatid mites. Soil Biology and Biochemistry 123, 155-164. doi: 10.1016/j.soilbio.2018.05.011
More information:  doi.org
Doc
Prey spectrum of forest soil predators across a land-use gradient using molecular gut content analysis
Günther B. (2012): Prey spectrum of forest soil predators across a land-use gradient using molecular gut content analysis. Master thesis, University Goettingen
Doc
Variationen in der Beutewahl von Hundertfüssern in Waldböden
Günther B., Rall B. C., Ferlian O., Scheu S., Eitzinger B. (2014): Variations in prey consumption of centipede predators in forest soils as indicated by molecular gut content analysis. Oikos 123 (10), 1192–1198. doi: 10.1111/j.1600-0706.2013.00868.x
More information:  doi.org
Doc
Fettsäuremuster als Biomarker für trophische Interaktionen: Veränderungen nach Nahrungswechsel und Hungern
Haubert D., Pollierer M. M., Scheu S. (2011): Fatty acid patterns as biomarker for trophic interactions: Changes after dietary switch and starvation. Soil Biology & Biochemistry 43, 490-494. doi: 10.1016/j.soilbio.2010.10.008
More information:  doi.org
Doc
Klarner B. (2013): Changes in trophic structure of decomposer communities with land use in Central European temperate forests. Dissertation, University Goettingen
More information:  ediss.uni-goettingen.de
Doc
Aufzeigen von Veränderungen der Ernährungsweise von Bodentieren in Wäldern unterschiedlicher Bewirtschaftung mittels stabiler Isotope
Klarner B., Ehnes R. B., Erdmann G., Eitzinger B., Pollierer M. M., Maraun M., Scheu S. (2014): Trophic shift of soil animal species with forest type as indicated by stable isotope analysis. Oikos 123 (10), 1173–1181. doi: 10.1111/j.1600-0706.2013.00939.x
More information:  doi.org
Doc
Trophische Diversität und Nischentrennung in einer artenreichen Räubergilde; Natürliche Variation in stabilen Isotopenverhältnissen (13C/12C und 15N/14N) von Raubmilben (Acari, Mesostigmata) mitteleuropäischer Buchenwälder
Klarner B., Maraun M., Scheu S. (2013): Trophic diversity and niche partitioning in a species rich predator guild – Natural variations in stable isotope ratios (13C/12C, 15N/14N) of mesostigmatid mites (Acari, Mesostigmata) from Central European beech forests. Soil Biology and Biochemistry 57, 327–333. doi: 10.1016/j.soilbio.2012.08.013
More information:  doi.org
Doc
Kompartimentierung und Energie-Kanäle im Bodentier-Nahrungsnetz untersucht mit stabiler Isotopen- und Fettsäuremuster-Analyse
Maraun M. (2012): Compartmentalization and energy channels within the soil animal food web investigated by stable isotope and fatty acid analyses. Dissertation, University Goettingen
More information:  ediss.uni-goettingen.de
Doc
Analysing the litter food web: Molecular detection of springtails (Insecta: Collembola) in arthropod predators
Micic A.(2009): Analysing the litter food web: Molecular detection of springtails (Insecta: Collembola) in arthropod predators. Thesis, Technische Universität Darmstadt
Doc
Zeitliche Dynamik und Varianz von Phospholipiden aus Boden und Streu in verschiedenen Wäldern und Regionen Deutschlands und der Einfluss von Landnutzung
Pollierer M. M., Ferlian O., Scheu S. (2015): Temporal dynamics and variation with forest type of phospholipid fatty acids in litter and soil of temperate forests across regions. Soil Biology& Biochemistry 91, 248-257. doi: 10.1016/j.soilbio.2015.08.035
More information:  doi.org
Doc
Diversität und funktionelle Struktur von Bodentiergemeinschaften legen nahe, dass Bodentier-Nahrungsnetze gegenüber Änderungen in der Waldnutzung gepuffert sind
Pollierer M. M., Klarner B., Ott D. Digel C., Ehnes R. B., Eitzinger B., Erdmann G., Brose U., Maraun M., Scheu S. (2021): Diversity and functional structure of soil animal communities suggest soil animal food webs to be buffered against changes in forest land use. Oecologia 196, 195–209. doi: 10.1007/s00442-021-04910-1
More information:  doi.org
Doc
Bestimmende Faktoren und zeitliche Fluktuation von Collembola Gemeinschaften und Reproduktionsweise in unterschiedlichen Waldtypen und Regionen
Pollierer M. M., Scheu S. (2017): Driving factors and temporal fluctuation of Collembola communities and reproductive mode across forest types and regions. Ecology and Evolution 7 (12), 4390-4403. doi: 10.1002/ece3.3035/10.1002/ece3.3035
More information:  doi.org
Doc
Stabile Isotope von Aminosäuren weisen darauf hin, dass Zersetzer-Mikroarthropoden im Boden sich hauptsächlich von saprotrophen Pilzen ernähren
Pollierer M. M., Scheu S. (2021): Stable isotopes of amino acids indicate that soil decomposer microarthropods predominantly feed on saprotrophic fungi. Ecosphere 12 (3), e03425. doi: 10.1002/ecs2.3425
More information:  doi.org
Doc
Trophischer Transfer von Marker-Fettsäuren von der basalen Ressource zum Prädator
Pollierer M. M., Scheu S., Haubert D. (2010): Taking it to the next level: Trophic transfer of marker fatty acids from basal resource to predators. Soil Biology & Biochemistry 42, 919-925. doi: 10.1016/j.soilbio.2010.02.008
More information:  doi.org
Doc
Phylogenetic diversity as proxy for functional diversity
Unger E. M. (2015): Phylogenetic diversity as proxy for functional diversity. Master thesis, University Göttingen
Doc
Auswirkungen von Landnutzung auf die Nematodengesellschaften in Wäldern gemäßigter Breiten
Wagner K. (2010): Auswirkungen von Landnutzung auf die Nematodengesellschaften in Wäldern gemäßigter Breiten. Thesis, HU Berlin
Doc
Basal resources and trophic level of macrofauna decomposers in beech and spruce forests as indicated by amino acid isotopes of carbon and nitrogen
Zusammensetzung von basalen Ressourcen und dem trophischen Level von Makrofauna Zersetzern in Buchen und Fichtenwald, wie von stabilen Isotopen von Kohlenstoff und Stickstoff in Aminosäuren angegeben
Wenglein R. (2021): Basal resources and trophic level of macrofauna decomposers in beech and spruce forests as indicated by amino acid isotopes of carbon and nitrogen. Master thesis, University Göttingen

Project in other funding periods

Centipede on a brown leaf
LitterLinks (Contributing project)
#Animals  #Soil biology & Element Cycling  #2011 – 2014  #2008 – 2011  #Biodiversity […]
Photo shows a springtail on the forest floor
LitterLinks (Contributing project)
#Animals  #Soil biology & Element Cycling  #2017 – 2020  #Biodiversity […]

Scientific assistants

Prof. Dr. Stefan Scheu
Project manager
Prof. Dr. Stefan Scheu
Georg-August-Universität Göttingen
Dr. Melanie Maraun
Employee
Dr. Melanie Maraun
Georg-August-Universität Göttingen
Dr. Sarah Bluhm
Employee
Dr. Sarah Bluhm
Georg-August-Universität Göttingen
André Junggebauer
Employee
André Junggebauer
Georg-August-Universität Göttingen
Prof. Dr. Mark Maraun
Employee
Prof. Dr. Mark Maraun
Georg-August-Universität Göttingen
Xue Pan
Employee
Xue Pan
Georg-August-Universität Göttingen
Top