Changes in soil food web structure of the decomposer system with land use intensity in forest systems

Picture: The photo shows an earthworm and a horn mite on the forest floor.

Goals

In our project “LitterLinks“, we investigate the effect of forest land-use on structure of soil animal communities and their trophic interactions. 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 roles we know little about these creatures and their interactions, much due to their small size, high diversity but also their opaque lifestyle.

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

In our “trenching-experiment”, we want to investigate the importance of above-ground processes for structure of the soil food web. By cutting tree roots we stopped flow of root exsudates into soil, thereby reducing an important nutrient resource for mycorrhizal fungi and bacteria which will eventually alter the microbial and animal community.

Hypotheses

Land-use change alters composition of animal decomposer community in a predictable way.
Land-use change has only little effect on type and strength of trophic interaction between decomposer animals and their food resources.

Methods

We record abundance and diversity of soil animals using heat extraction of soil cores. To characterize land-use types we also record biotic and abiotic factors, such as microbial biomass, soi pH and litter mass.

To analyse trophic interactions we employ three different methods, which allow us to illustrate the soil food web in unmatched detail: We use stable isotope analysis (ratios of ¹³C/¹²C- and ¹⁵N/¹⁴N) to identify trophic level and basal resources of soil animals. Fatty acid analysis shows if a consumer is linked to the bacterial or fungal pathway in soil. PCR-based molecular gut content analysis detects prey DNA in the guts of animal consumers and allows species-specific tracking of trophic interactions. This method will also be used to screen guts of collembolan and oribatid mites for mycorrhizal fungi, soil algae and nematode prey and to assess their respective importance in differently managed forests. All these data will then be used to model whole food webs and to assess effect of land-use on structure and dynamcis of soil animal communities.

Picture: The collage includes five photos and a diagram. Photo one shows sample tubes in seven different colored collection containers in orange, yellow, blue, red, and green. Photo two shows a female scientist smiling at the camera in the forest. Photo three shows a female scientist smiling at the camera with a backpack on a rocky plateau, with forested slopes in the background. Photo four shows four scientists crouching on the forest floor smiling at the camera in front of a square piece of ground marked with low black dividers. Photo five shows laboratory utensils in a room and two hands, the right hand holding a pipette and the left hand holding a sample tube. The diagram contrasts forest-dwelling predatory insects and composting insects in a graph.

Publications

Effects of forest gap formation and deadwood enrichment on oribatid mites (Acari: Oribatida) vary between regions

Die Auswirkungen Waldlückenbildung und Totholzanreicherung auf die Mikroarthropoden im Boden variieren von Region zu Region

Junggebauer A., Gericke N. M., Krakau K.L., Bluhm S. L., Maraun M., Pollierer M. M., Scheu S. (2024): Effects of forest gap formation and deadwood enrichment on oribatid mites (Acari: Oribatida) vary between regions. Forest Ecology and Management 565: 122015. doi: 10.1016/j.foreco.2024.122015

Opening up new niche dimensions: The stoichiometry of soil microarthropods in European beech and Norway spruce forests

Die stöchiometrische Nische im Bodensystem: eine Untersuchung der Elementgehalte von Bodenmilben in Buchen- und Fichtenwäldern

Warnke L., Hertel D., Scheu S., Maraun M. (2023): Opening up new niche dimensions: The stoichiometry of soil microarthropods in European beech and Norway spruce forests. Ecology and Evolution 13, e10122. doi: 10.1002/ece3.10122

Collembola communities across forest ecosystems in Germany: Long-term dynamics and interrelationships with fungal food resources

Jüds M. (2023): Collembola communities across forest ecosystems in Germany: Long-term dynamics and interrelationships with fungal food resources. Dissertation, University Göttingen. doi: 10.53846/goediss-9896

Amino acid isotopes in functional assemblages of Collembola reveal the influence of vertical resource heterogeneity and root energy supply on trophic interactions in soil food webs

Der Einfluss von wurzelbasierter Energieversorgung und vertikaler Ressourcenheterogenität auf die trophische Struktur von Springschwanz-Gemeinschaften, untersucht mit komponentenspezifischer Analyse von Aminosäureisotopen.

Li Z., Bluhm S. L., Scheu S., Pollierer M. M. (2022): Amino acid isotopes in functional assemblages of Collembola reveal the influence of vertical resource heterogeneity and root energy supply on trophic interactions in soil food webs. Soil Biology and Biochemistry 174, 108815. doi: 10.1016/j.soilbio.2022.108815

The stoichiometric niche in soil systems: Investigating the elemental composition of soil mites in beech and spruce forests

Die stöchiometrische Nische im Bodensystem: eine Untersuchung der Elementgehalte von Bodenmilben in Buchen- und Fichtenwäldern

Warnke L. (2022): The stoichiometric niche in soil systems: Investigating the elemental composition of soil mites in beech and spruce forests. Bachelor thesis, University Göttingen

The impact of root-derived resources on forest soil invertebrates depends on body size and trophic position

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

Diversity and functional structure of soil animal communities suggest soil animal food webs to be buffered against changes in forest land use

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

Stable isotopes of amino acids indicate that soil decomposer microarthropods predominantly feed on saprotrophic fungi

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

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

Deprivation of root-derived resources affects microbial biomass but not community structure in litter and soil

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

Protura are unique: first evidence of specialized feeding on ectomycorrhizal fungi in soil invertebrates

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

Testing the validity of functional response models using molecular gut content analysis for prey choice in soil predators

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

Phylogenetic and trophic determinants of gut microbiota in soil oribatid mites

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

Driving factors and temporal fluctuation of Collembola communities and reproductive mode across forest types and regions

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

Temporal dynamics and variation with forest type of phospholipid fatty acids in litter and soil of temperate forests across regions

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

Phylogenetic diversity as proxy for functional diversity

Unger E. M. (2015): Phylogenetic diversity as proxy for functional diversity. Master thesis, University Göttingen

Trophic niche differentiation and utilisation of food resources in collembolans based on complementary analyses of fatty acids and stable isotopes

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

Shifts in trophic interactions with forest type in soil generalist predators as indicated by complementary analyses of fatty acids and stable isotopes

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

Effects of prey quality and predator body size on prey DNA detection success in a centipede predator

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

Variations in prey consumption of centipede predators in forest soils as indicated by molecular gut content analysis

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

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

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

Carbon food resources of earthworms of different ecological groups as indicated by 13C compound-specific stable isotope analysis

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

Trophic shift of soil animal species with forest type as indicated by stable isotope analysis

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

Unveiling soil food web links: New PCR assays for detection of prey DNA in the gut of soil arthropod predators

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

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

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

Molecular analysis of centipede predation

Molekulare Analyse der Ernährung von Hundertfüssern (Chilopoda)

Eitzinger B. (2013): Molecular analysis of centipede predation. Dissertation, University of Goettingen

Changes in trophic structure of decomposer communities with land use in Central European temperate forests

Klarner B. (2013): Changes in trophic structure of decomposer communities with land use in Central European temperate forests. Dissertation, University Goettingen

Trophic interactions in centipedes (Chilopoda, Myriapoda) as indicated by fatty acid patterns: Variations with life stage, forest age and season

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

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

Compartmentalization and energy channels within the soil animal food web investigated by stable isotope and fatty acid analyses

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

Fatty acid patterns as biomarker for trophic interactions: Changes after dietary switch and starvation

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

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

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

Taking it to the next level: Trophic transfer of marker fatty acids from basal resource to predators

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

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