Maraun, Mark

[["dc.bibliographiccitation.artnumber","e0207141"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","PLOS ONE"],["dc.bibliographiccitation.volume","13"],["dc.contributor.author","Winter, Marlena"],["dc.contributor.author","Haynert, Kristin"],["dc.contributor.author","Scheu, Stefan"],["dc.contributor.author","Maraun, Mark"],["dc.date.accessioned","2019-07-09T11:49:40Z"],["dc.date.available","2019-07-09T11:49:40Z"],["dc.date.issued","2018"],["dc.description.abstract","Global change processes affect seasonal dynamics of salt marshes and thereby their plant and animal communities. However, these changes have been little investigated for microarthropod communities. We studied the effect of seasonality and changes in sea level on oribatid mites in the natural salt marsh and on artificial islands in the back-barrier environment of the island Spiekeroog (Wadden Sea, Germany). Three zones of the artificial islands were filled with transplanted sods from the lower salt marsh zone and thereby exposed to three different inundation frequencies. We hypothesized that oribatid mite communities will differ along the natural salt marsh vegetation zones [upper salt marsh (USM), lower salt marsh (LSM), pioneer zone (PZ)], which are influenced by different tidal regimes. Accordingly, total oribatid mite densities declined from the USM and LSM to the PZ. Similarly, oribatid mite species compositions changed along the salt marsh transect and also responded to variations in inundation frequency in LSM on artificial islands with typical species of the USM, LSM and PZ being Multioppia neglecta (USM), Hermannia pulchella (LSM), Zachvatkinibates quadrivertex (LSM, PZ) and Ameronothrus schneideri (LSM, PZ). Oribatid mite density in the salt marsh and on the artificial islands was at a maximum in winter and spring; this was due in part to high density of juveniles, pointing to two reproductive periods. We hypothesized that oribatid mite trophic structure changes due to variations in abiotic (e.g., tidal dynamics, temperature) and biotic conditions (e.g., resource availability). Stable isotope (15N, 13C) and neutral lipid fatty acid analyses indicated that oribatid mite species have different diets with e.g., Z. quadrivertex feeding on macroalgae and fungi, A. schneideri feeding on microalgae and bacteria, and Scheloribates laevigatus and M. neglecta feeding on dead organic matter, bacteria and fungi. Overall, the results indicate that oribatid mite species in salt marshes are affected by changes in environmental factors such as inundation intensity, with the effects being most pronounced in species with narrow trophic niches and limited niche plasticity. The results also indicate that oribatid mite communities of the LSM respond little to short-term (one year) changes in inundation frequency."],["dc.identifier.doi","10.1371/journal.pone.0207141"],["dc.identifier.pmid","30408121"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15737"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59603"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.orgunit","Zentrum für Biodiversität und Nachhaltige Landnutzung"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","570"],["dc.title","Seasonal dynamics and changing sea level as determinants of the community and trophic structure of oribatid mites in a salt marsh of the Wadden Sea"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e0189645"],["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","PloS one"],["dc.bibliographiccitation.lastpage","20"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Haynert, Kristin"],["dc.contributor.author","Kiggen, Mirijam"],["dc.contributor.author","Klarner, Bernhard"],["dc.contributor.author","Maraun, Mark"],["dc.contributor.author","Scheu, Stefan"],["dc.date.accessioned","2019-07-09T11:45:04Z"],["dc.date.available","2019-07-09T11:45:04Z"],["dc.date.issued","2017"],["dc.description.abstract","Mesofauna taxa fill key trophic positions in soil food webs, even in terrestrial-marine boundary habitats characterized by frequent natural disturbances. Salt marshes represent such boundary habitats, characterized by frequent inundations increasing from the terrestrial upper to the marine pioneer zone. Despite the high abundance of soil mesofauna in salt marshes and their important function by facilitating energy and carbon flows, the structure, trophic ecology and habitat-related diet shifts of mesofauna species in natural salt marsh habitats is virtually unknown. Therefore, we investigated the effects of natural disturbance (inundation frequency) on community structure, food web complexity and resource use of soil mesofauna using stable isotope analysis (15N, 13C) in three salt marsh zones. In this intertidal habitat, the pioneer zone is exposed to inundations twice a day, but lower and upper salt marshes are less frequently inundated based on shore height. The mesofauna comprised 86 species / taxa dominated by Collembola, Oribatida and Mesostigmata. Shifts in environmental disturbances influenced the structure of food webs, diversity and density declined strongly from the land to the sea pointing to the importance of increasing levels of inundation frequency. Accordingly, the reduced diversity and density was associated by a simplification of the food web in the pioneer zone as compared to the less inundated lower and upper salt marsh with a higher number of trophic levels. Strong variations in δ15N signatures demonstrated that mesofauna species are feeding at multiple trophic levels. Primary decomposers were low and most mesofauna species functioned as secondary decomposers or predators including second order predators or scavengers. The results document that major decomposer taxa, such as Collembola and Oribatida, are more diverse than previously assumed and predominantly dwell on autochthonous resources of the respective salt marsh zone. The results further suggest that Mesostigmata mostly adopt an intraguild predation lifestyle. The high trophic position of a large number of predators suggests that intraguild predation is of significant importance in salt marsh food webs. Presumably, intraguild predation contributes to stabilizing the salt marsh food web against disturbances."],["dc.identifier.doi","10.1371/journal.pone.0189645"],["dc.identifier.pmid","29240806"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15029"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59156"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","570"],["dc.subject.mesh","Animals"],["dc.subject.mesh","Biodiversity"],["dc.subject.mesh","Food Chain"],["dc.subject.mesh","Germany"],["dc.subject.mesh","Humans"],["dc.subject.mesh","Predatory Behavior"],["dc.subject.mesh","Soil"],["dc.subject.mesh","Wetlands"],["dc.title","The structure of salt marsh soil mesofauna food webs - The prevalence of disturbance"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","873"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Nature communications"],["dc.bibliographiccitation.volume","8"],["dc.contributor.author","Brandt, Alexander"],["dc.contributor.author","Schaefer, Ina"],["dc.contributor.author","Glanz, Julien"],["dc.contributor.author","Schwander, Tanja"],["dc.contributor.author","Maraun, Mark"],["dc.contributor.author","Scheu, Stefan"],["dc.contributor.author","Bast, Jens"],["dc.date.accessioned","2019-07-09T11:44:34Z"],["dc.date.available","2019-07-09T11:44:34Z"],["dc.date.issued","2017-10-12"],["dc.description.abstract","Sex is beneficial in the long term because it can prevent mutational meltdown through increased effectiveness of selection. This idea is supported by empirical evidence of deleterious mutation accumulation in species with a recent transition to asexuality. Here, we study the effectiveness of purifying selection in oribatid mites which have lost sex millions of years ago and diversified into different families and species while reproducing asexually. We compare the accumulation of deleterious nonsynonymous and synonymous mutations between three asexual and three sexual lineages using transcriptome data. Contrasting studies of young asexual lineages, we find evidence for strong purifying selection that is more effective in asexual as compared to sexual oribatid mite lineages. Our results suggest that large populations likely sustain effective purifying selection and facilitate the escape of mutational meltdown in the absence of sex. Thus, sex per se is not a prerequisite for the long-term persistence of animal lineages.Asexual reproduction is thought to be an evolutionary dead end in eukaryotes because deleterious mutations will not be purged effectively. Here, Brandt and colleagues show that anciently asexual oribatid mites in fact have reduced accumulation of deleterious mutations compared to their sexual relatives."],["dc.identifier.doi","10.1038/s41467-017-01002-8"],["dc.identifier.pmid","29026136"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14820"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59038"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","2041-1723"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","570"],["dc.title","Effective purifying selection in ancient asexual oribatid mites."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e0214233"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","PLOS ONE"],["dc.bibliographiccitation.volume","14"],["dc.contributor.author","Bluhm, Sarah L."],["dc.contributor.author","Eitzinger, Bernhard"],["dc.contributor.author","Ferlian, Olga"],["dc.contributor.author","Bluhm, Christian"],["dc.contributor.author","Schröter, Kristina"],["dc.contributor.author","Pena, Rodica"],["dc.contributor.author","Maraun, Mark"],["dc.contributor.author","Scheu, Stefan"],["dc.date.accessioned","2019-07-09T11:51:02Z"],["dc.date.available","2019-07-09T11:51:02Z"],["dc.date.issued","2019"],["dc.description.abstract","The input of plant leaf litter has been assumed to be the most important resource for soil organisms of forest ecosystems, but there is increasing evidence that root-derived resources may be more important. By trenching roots of trees in deciduous and coniferous forests, we cut-off the input of root-derived resources and investigated the response of microorganisms using substrate-induced respiration and phospholipid fatty acid (PLFA) analysis. After one and three years, root trenching strongly decreased microbial biomass and concentrations of PLFAs by about 20%, but the microbial community structure was little affected and the effects were similar in deciduous and coniferous forests. However, the reduction in microbial biomass varied between regions and was more pronounced in forests on limestone soils (Hainich) than in those on sandy soils (Schorfheide). Trenching also reduced microbial biomass in the litter layer but only in the Hainich after one year, whereas fungal and bacterial marker PLFAs as well as the fungal-to-plant marker ratio in litter were reduced in the Schorfheide both after one and three years. The pronounced differences between forests of the two regions suggest that root-derived resources are more important in fueling soil microorganisms of base-rich forests characterized by mull humus than in forests poor in base cations characterized by moder soils. The reduction in microbial biomass and changes in microbial community characteristics in the litter layer suggests that litter microorganisms do not exclusively rely on resources from decomposing litter but also from roots, i.e. from resources based on labile recently fixed carbon. Our results suggest that both bacteria and fungi heavily depend on root-derived resources with both suffering to a similar extent to deprivation of these resources. Further, the results indicate that the community structure of microorganisms is remarkably resistant to changes in resource supply and adapts quickly to new conditions irrespective of tree species composition and forest management."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2019"],["dc.identifier.doi","10.1371/journal.pone.0214233"],["dc.identifier.pmid","30921392"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16033"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16066"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59861"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.doi","10.1371/journal.pone.0214233.g001"],["dc.relation.doi","10.1371/journal.pone.0214233.g002"],["dc.relation.doi","10.1371/journal.pone.0214233.g003"],["dc.relation.doi","10.1371/journal.pone.0214233.g004"],["dc.relation.doi","10.1371/journal.pone.0214233.t001"],["dc.relation.doi","10.1371/journal.pone.0214233.t002"],["dc.relation.doi","10.1371/journal.pone.0214233.s001"],["dc.relation.doi","10.1371/journal.pone.0214233.s002"],["dc.relation.doi","10.1371/journal.pone.0214233.s003"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","570"],["dc.title","Deprivation of root-derived resources affects microbial biomass but not community structure in litter and soil"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.journal","Ecology and Evolution"],["dc.bibliographiccitation.lastpage","12"],["dc.contributor.author","Marian, Franca"],["dc.contributor.author","Sandmann, Dorothee"],["dc.contributor.author","Krashevska, Valentyna"],["dc.contributor.author","Maraun, Mark"],["dc.contributor.author","Scheu, Stefan"],["dc.date.accessioned","2019-07-09T11:43:35Z"],["dc.date.available","2019-07-09T11:43:35Z"],["dc.date.issued","2017"],["dc.description.abstract","We investigated how altitude affects the decomposition of leaf and root litter in the Andean tropical montane rainforest of southern Ecuador, that is, through changes in the litter quality between altitudes or other site-specific differences in microenvironmental conditions. Leaf litter from three abundant tree species and roots of different diameter from sites at 1,000, 2,000, and 3,000 m were placed in litterbags and incubated for 6, 12, 24, 36, and 48 months. Environmental conditions at the three altitudes and the sampling time were the main factors driving litter decomposition, while origin, and therefore quality of the litter, was of minor importance. At 2,000 and 3,000 m decomposition of litter declined for 12 months reaching a limit value of ~50% of initial and not decomposing further for about 24 months. After 36 months, decomposition commenced at low rates resulting in an average of 37.9% and 44.4% of initial remaining after 48 months. In contrast, at 1,000 m decomposition continued for 48 months until only 10.9% of the initial litter mass remained. Changes in decomposition rates were paralleled by changes in microorganisms with microbial biomass decreasing after 24 months at 2,000 and 3,000 m, while varying little at 1,000 m. The results show that, irrespective of litter origin (1,000, 2,000, 3,000 m) and type (leaves, roots), unfavorable microenvironmental conditions at high altitudes inhibit decomposition processes resulting in the sequestration of carbon in thick organic layers."],["dc.identifier.doi","10.1002/ece3.3189"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14584"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58921"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","2045-7758"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","570"],["dc.title","Leaf and root litter decomposition is discontinued at high altitude tropical montane rainforests contributing to carbon sequestration"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","321"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Ecology and Evolution"],["dc.bibliographiccitation.lastpage","337"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Pachl, Patrick"],["dc.contributor.author","Uusitalo, Matti"],["dc.contributor.author","Scheu, Stefan"],["dc.contributor.author","Schaefer, Ina"],["dc.contributor.author","Maraun, Mark"],["dc.date.accessioned","2021-04-14T08:30:57Z"],["dc.date.available","2021-04-14T08:30:57Z"],["dc.date.issued","2020"],["dc.description.abstract","Abstract The existence of old species‐rich parthenogenetic taxa is a conundrum in evolutionary biology. Such taxa point to ancient parthenogenetic radiations resulting in morphologically distinct species. Ancient parthenogenetic taxa have been proposed to exist in bdelloid rotifers, darwinulid ostracods, and in several taxa of acariform mites (Acariformes, Acari), especially in oribatid mites (Oribatida, Acari). Here, we investigate the diversification of Acariformes and their ancestral mode of reproduction using 18S rRNA. Because parthenogenetic taxa tend to be more frequent in phylogenetically old taxa of Acariformes, we sequenced a wide range of members of this taxon, including early‐derivative taxa of Prostigmata, Astigmata, Endeostigmata, and Oribatida. Ancestral character state reconstruction indicated that (a) Acariformes as well as Oribatida evolved from a sexual ancestor, (b) the primary mode of reproduction during evolution of Acariformes was sexual; however, species‐rich parthenogenetic taxa radiated independently at least four times (in Brachychthonioidea (Oribatida), Enarthronota (Oribatida), and twice in Nothrina (Oribatida), (c) parthenogenesis additionally evolved frequently in species‐poor taxa, for example, Tectocepheus, Oppiella, Rostrozetes, Limnozetes, and Atropacarus, and (d) sexual reproduction likely re‐evolved at least three times from species‐rich parthenogenetic clusters, in Crotonia (Nothrina), in Mesoplophora/Apoplophora (Mesoplophoridae, Enarthronota), and in Sphaerochthonius/Prototritia (Protoplophoridae, Enarthronota). We discuss possible reasons that favored the frequent diversification of parthenogenetic taxa including the continuous long‐term availability of dead organic matter resources as well as generalist feeding of species as indicated by natural variations in stable isotope ratios."],["dc.description.abstract","We investigated the radiation of Acariformes and reconstructed their ancestral mode of reproduction using 18S rDNA. We found that (a) Acariformes as well as Oribatida evolved from a sexual ancestor, (b) species‐rich parthenogenetic taxa radiated independently at least four times in Acariformes, (c) parthenogenesis additionally evolved frequently in species‐poor taxa/genera and (d) sexual reproduction likely re‐evolved at least three times from species‐rich parthenogenetic clusters image"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.1002/ece3.7047"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/17786"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/83431"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.notes.intern","Merged from goescholar"],["dc.notes.intern","In goescholar not merged with http://resolver.sub.uni-goettingen.de/purl?gs-1/17839 but duplicate"],["dc.relation.eissn","2045-7758"],["dc.relation.issn","2045-7758"],["dc.relation.orgunit","Zentrum für Biodiversität und Nachhaltige Landnutzung"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.subject.ddc","570"],["dc.title","Repeated convergent evolution of parthenogenesis in Acariformes (Acari)"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e0180915"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","PLOS ONE"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Klarner, Bernhard"],["dc.contributor.author","Winkelmann, Helge"],["dc.contributor.author","Krashevska, Valentyna"],["dc.contributor.author","Maraun, Mark"],["dc.contributor.author","Widyastuti, Rahayu"],["dc.contributor.author","Scheu, Stefan"],["dc.date.accessioned","2019-07-09T11:43:29Z"],["dc.date.available","2019-07-09T11:43:29Z"],["dc.date.issued","2017"],["dc.description.abstract","Conversion of tropical rainforests into plantations fundamentally alters ecological niches of animal species. Generalist predators such as centipedes (Chilopoda) may be able to persist in converted ecosystems due to their ability to adapt and switch to alternative prey populations. We investigated variations in community composition and trophic niches of soil and litter living centipedes in a range of ecosystems including rainforests, jungle rubber agroforests, and rubber and oil palm monocultures in two landscapes in Sumatra, Indonesia. Including information on environmental factors in the soil and litter habitat, we explored drivers shaping ecological niches of soil living invertebrate predators in one of the world's hotspots of rainforest conversion. Conversion of rainforests into agroforests and plantations was associated with a marked change in the composition of centipede communities. However, irrespective of major differences in habitat characteristics, changes in total abundances were small and the overall diversity and biomass of centipedes was similar in each of the systems investigated, suggesting that the number of ecological niches for this group of predators remains unchanged. By using stable isotope analysis (15N and 13C), we investigated trophic niche shifts of the centipede community; lower δ13C values of centipedes in oil palm plantations as compared to other ecosystems suggests that centipedes switch from decomposer prey to other prey, presumably understory associated herbivores, due to reduced availability of litter associated prey species. The results suggest that the ability to utilize alternative prey is a key feature enabling invertebrate predators to persist in ecosystems undergoing major structural changes due to anthropogenic land use change."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2017"],["dc.identifier.doi","10.1371/journal.pone.0180915"],["dc.identifier.pmid","28763453"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14544"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58895"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation","SFB 990: Ökologische und sozioökonomische Funktionen tropischer Tieflandregenwald-Transformationssysteme (Sumatra, Indonesien)"],["dc.relation","SFB 990 | B | B08: Struktur und Funktion des Zersetzersystems in Transformationssystemen von Tiefland-Regenwäldern"],["dc.relation","SFB 990 | B | B13: Impact of management intensity and tree enrichment of oil palm plantations on below- and aboveground invertebrates in Sumatra (Indonesia)"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","570"],["dc.subject.gro","sfb990_journalarticles"],["dc.title","Trophic niches, diversity and community composition of invertebrate top predators (Chilopoda) as affected by conversion of tropical lowland rainforest in Sumatra (Indonesia)."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]