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Mark Maraun - One of the best experts on this subject based on the ideXlab platform.
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free living nematodes as prey for higher trophic levels of forest Soil food webs
Oikos, 2014Co-Authors: Kerstin Heidemann, Stefan Scheu, Annika Hennies, Johanna Schakowske, Lars Blumenberg, Liliane Ruess, Mark MaraunAbstract:Nematodes are the most abundant invertebrates in Soils and are key prey in Soil food webs. Uncovering their contribution to predator nutrition is essential for understanding the structure of Soil food webs and the way energy channels through Soil systems. Molecular gut content analysis of consumers of nematodes, such as Soil Microarthropods, using specifi c DNA markers is a novel approach for studying predator – prey interactions in Soil. We designed new specifi c primer pairs (partial 18S rDNA) for individual Soil-living bacterial-feeding nematode taxa ( Acrobeloides buetschlii, Panagrellus redivivus, Plectus velox and Plectus minimus ). Primer specifi city was tested against more than 100 non-target Soil organisms. Further, we determined how long nematode DNA can be traced in the gut of predators. Potential predators were identifi ed in laboratory experiments including nine Soil mite (Oribatida, Gamasina and Uropodina) and ten springtail species (Collembola). Finally, the approach was tested under fi eld conditions by analyzing fi ve mite and three collembola species for feeding on the three target nematode species. Th e results proved the three primer sets to specifi cally amplify DNA of the respective nematode taxa. Detection time of nematode DNA in predators varied with time of prey exposure. Further, consumption of nematodes in the laboratory varied with microarthropod species. Our fi eld study is the fi rst defi nitive proof that free-living nematodes are important prey for a wide range of Soil Microarthropods including those commonly regarded as detritivores. Overall, the results highlight the eminent role of nematodes as prey in Soil food webs and for channelling bacterial carbon to higher trophic levels.
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resource availability as driving factor of the reproductive mode in Soil Microarthropods acari oribatida
PLOS ONE, 2014Co-Authors: Katja Wehner, Stefan Scheu, Mark MaraunAbstract:The availability of high quality resources is an important factor driving community structure and reproductive mode of animals. Parthenogenetic reproduction prevails when resources are available in excess, whereas sexuality correlates with resource shortage. We investigated the effect of resource availability on the community structure of oribatid mites in a laboratory experiment. Availability of food resources was increased by addition of glucose to leaf litter and reduced by leaching of nutrients from leaf litter. Experimental systems were incubated at three different temperatures to establish different regimes of resource exploitation. Community structure of oribatids and numbers of eggs per female were measured over a period of ten months. We expected the density of oribatid mites to decline in the reduced litter quality treatment but to increase in the glucose treatment. Both effects were assumed to be more pronounced at higher temperatures. We hypothesized sexual species to be less affected than parthenogenetic species by reduced resource quality due to higher genetic diversity allowing more efficient exploitation of limited resources, but to be outnumbered by parthenogenetic species in case of resource addition due to faster reproduction. In contrast to our hypotheses, both sexual and parthenogenetic oribatid mite species responded similarly with their densities declining uniformly during incubation. The parthenogenetic Brachychthoniidae and Tectocepheus dominated early in the experiment but were replaced later by parthenogenetic Desmonomata and Rhysotritia. In parthenogenetic species the number of eggs per female increased during the experiment while the number of eggs in sexual females remained constant or decreased slightly; in general, egg numbers were higher in sexual than in parthenogenetic species. The results indicate that for sustaining oribatid mite populations other resources than litter and associated saprotrophic microorganisms are needed. They also indicate that there are two groups of parthenogenetically reproducing species: exploiters of easily available resources and consumers of leaf litter associated resources.
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feeding preferences among dark pigmented fungal taxa dematiacea indicate limited trophic niche differentiation of oribatid mites oribatida acari
Pedobiologia, 2005Co-Authors: Katja Schneider, Mark MaraunAbstract:Summary Trophic niche differentiation may explain the high diversity of Soil animal species. However, trophic niches of Soil invertebrate species are little understood and it appears that different decomposer Soil animal species prefer similar food substrates. Soil Microarthropods, such as collembolans and oribatid mites, preferentially feed on dark pigmented fungi (“Dematiacea”) but their feeding preferences among different dark pigmented fungal species are little studied. In this study, we offered eight dark pigmented fungal taxa ( Alternaria alternata , Bipolaris spicifera , Chloridium sp., Cladosporium sp., Codinea sp., Oidiodendron sp., Phialophora verrucosa , Ulocladium sp.) and two little pigmented fungal species ( Aureobasidium pullulans and Mortierella ramanniana ) to 10 species of oribatid mites. Despite the overall trend of oribatid mites to prefer two of the dark pigmented fungi ( Alternaria alternata and Ulocladium sp.), feeding preferences significantly differed between the oribatid mite species. Achipteria coleoptrata , Carabodes sp., Liacarus subterraneus , Oribatella quadricornuta and Steganacarus magnus strongly preferred Alternaria alternata and Ulocladium sp.; Hypochthonius rufulus preferred Phialophora verrucosa . Species with low feeding preferences, Eupelops torulosus and Oribatula tibialis, preferentially fed on Ulocladium sp. and Codinea sp., respectively. The other species ( Nothrus silvestris , Platynothrus peltifer ) had no clear feeding preferences. The results support that trophic niche differentiation in oribatid mite species is limited, but may contribute to the high diversity of Soil animal species.
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trophic niche differentiation in Soil Microarthropods oribatida acari evidence from stable isotope ratios 15n 14n
Soil Biology & Biochemistry, 2004Co-Authors: Katja Schneider, Stefan Scheu, Sonja Migge, Roy A Norton, Reinhard Langel, August Reineking, Mark MaraunAbstract:Abstract The large number of animals that coexist in Soil without any clear niche differentiation has puzzled biologists for a long time. We investigated stable isotope ratios (15N/14N) in a diverse group of Soil Microarthropods, oribatid mites, to evaluate trophic niche differentiation. The natural variation of the stable isotopes 15N/14N was measured in 36 species/taxa from four beech and beech-oak forests. Signatures of δ15N formed a gradient spanning over 12 δ units suggesting that (a) different species occupy different trophic niches and (b) oribatid mites span three to four trophic levels. This study for the first time documented strong trophic niche differentiation in decomposer Microarthropods. The results suggest that trophic niche differentiation within taxonomic groups significantly contributes to the high diversity of Soil animal taxa.
Stefan Scheu - One of the best experts on this subject based on the ideXlab platform.
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Response of Collembola and Acari communities to summer flooding in a grassland plant diversity experiment
2018Co-Authors: Odette González-macé, Stefan ScheuAbstract:Flooding frequency is predicted to increase during the next decades in Europe. Therefore, it is important to understand how short-term disturbance events affect Soil biota providing essential ecosystem functions and uncover factors modulating their response such as plant community composition. Here we report on the response of Soil microarthropod communities (Collembola and Acari) to a severe summer flood in 2013, which affected major parts of central Europe. Collembola and Acari density and Collembola and Oribatida richness were strongly affected by the flood, but they recovered within three months. Effects of plant community composition on Soil Microarthropods disappeared after the flood, presumably due to homogenization of the field, but the effects of plant community were in a stage of being reasserted three months after the flood. Widespread, surface living and generalistic microarthropod species recolonized the field quickly. Prostigmata and Oribatida were more resilient or recovered to flooding than Astigmata and Gamasida. Long-term impacts, however, remain unknown and deserve further investigation.
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free living nematodes as prey for higher trophic levels of forest Soil food webs
Oikos, 2014Co-Authors: Kerstin Heidemann, Stefan Scheu, Annika Hennies, Johanna Schakowske, Lars Blumenberg, Liliane Ruess, Mark MaraunAbstract:Nematodes are the most abundant invertebrates in Soils and are key prey in Soil food webs. Uncovering their contribution to predator nutrition is essential for understanding the structure of Soil food webs and the way energy channels through Soil systems. Molecular gut content analysis of consumers of nematodes, such as Soil Microarthropods, using specifi c DNA markers is a novel approach for studying predator – prey interactions in Soil. We designed new specifi c primer pairs (partial 18S rDNA) for individual Soil-living bacterial-feeding nematode taxa ( Acrobeloides buetschlii, Panagrellus redivivus, Plectus velox and Plectus minimus ). Primer specifi city was tested against more than 100 non-target Soil organisms. Further, we determined how long nematode DNA can be traced in the gut of predators. Potential predators were identifi ed in laboratory experiments including nine Soil mite (Oribatida, Gamasina and Uropodina) and ten springtail species (Collembola). Finally, the approach was tested under fi eld conditions by analyzing fi ve mite and three collembola species for feeding on the three target nematode species. Th e results proved the three primer sets to specifi cally amplify DNA of the respective nematode taxa. Detection time of nematode DNA in predators varied with time of prey exposure. Further, consumption of nematodes in the laboratory varied with microarthropod species. Our fi eld study is the fi rst defi nitive proof that free-living nematodes are important prey for a wide range of Soil Microarthropods including those commonly regarded as detritivores. Overall, the results highlight the eminent role of nematodes as prey in Soil food webs and for channelling bacterial carbon to higher trophic levels.
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resource availability as driving factor of the reproductive mode in Soil Microarthropods acari oribatida
PLOS ONE, 2014Co-Authors: Katja Wehner, Stefan Scheu, Mark MaraunAbstract:The availability of high quality resources is an important factor driving community structure and reproductive mode of animals. Parthenogenetic reproduction prevails when resources are available in excess, whereas sexuality correlates with resource shortage. We investigated the effect of resource availability on the community structure of oribatid mites in a laboratory experiment. Availability of food resources was increased by addition of glucose to leaf litter and reduced by leaching of nutrients from leaf litter. Experimental systems were incubated at three different temperatures to establish different regimes of resource exploitation. Community structure of oribatids and numbers of eggs per female were measured over a period of ten months. We expected the density of oribatid mites to decline in the reduced litter quality treatment but to increase in the glucose treatment. Both effects were assumed to be more pronounced at higher temperatures. We hypothesized sexual species to be less affected than parthenogenetic species by reduced resource quality due to higher genetic diversity allowing more efficient exploitation of limited resources, but to be outnumbered by parthenogenetic species in case of resource addition due to faster reproduction. In contrast to our hypotheses, both sexual and parthenogenetic oribatid mite species responded similarly with their densities declining uniformly during incubation. The parthenogenetic Brachychthoniidae and Tectocepheus dominated early in the experiment but were replaced later by parthenogenetic Desmonomata and Rhysotritia. In parthenogenetic species the number of eggs per female increased during the experiment while the number of eggs in sexual females remained constant or decreased slightly; in general, egg numbers were higher in sexual than in parthenogenetic species. The results indicate that for sustaining oribatid mite populations other resources than litter and associated saprotrophic microorganisms are needed. They also indicate that there are two groups of parthenogenetically reproducing species: exploiters of easily available resources and consumers of leaf litter associated resources.
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invasion of a deciduous forest by earthworms changes in Soil chemistry microflora Microarthropods and vegetation
Soil Biology & Biochemistry, 2007Co-Authors: Nico Eisenhauer, Stephan Partsch, D Parkinson, Stefan ScheuAbstract:Abstract Ecosystems of northern North America existed without earthworm fauna until European settlers arrived and introduced European species. The current extent of invasion by some of these species, Lumbricus terrestris L., Octolasion tyrtaeum Savigny and Dendrobaena octaedra Savigny, into an aspen forest in the Canadian Rocky Mountains and the effects of the invasion on Soil chemistry, microflora, Soil Microarthropods and vegetation were investigated. Densities of earthworm species, Soil structure, plant coverage and abundance were determined along three transects starting at the edge of the forest. At locations with L. terrestris, litter was incorporated into the Soil, and where O. tyrtaeum was present, organic layers were mixed with mineral Soil layers. Organic layers disappeared almost entirely when both species occurred together. Carbon and nitrogen concentrations were reduced in organic layers in the presence of L. terrestris and O. tyrtaeum. Microbial biomass and basal respiration were reduced when L. terrestris and O. tyrtaeum were present, presumably due to resource competition and habitat destruction. Microarthropod densities and the number of microarthropod species were strongly reduced in the presence of O. tyrtaeum (−75% and −22%, respectively), probably through mechanical disturbances, increasing compactness of the Soil and resource competition. The coverage of some plant species was correlated with earthworm abundance, but the coverage of others was not. Despite harsh climatic conditions, the invasion of boreal forest ecosystems by mineral Soil dwelling earthworm species is proceeding and strongly impacts Soil structure, Soil chemistry, microorganisms, Soil Microarthropods and vegetation.
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trophic niche differentiation in Soil Microarthropods oribatida acari evidence from stable isotope ratios 15n 14n
Soil Biology & Biochemistry, 2004Co-Authors: Katja Schneider, Stefan Scheu, Sonja Migge, Roy A Norton, Reinhard Langel, August Reineking, Mark MaraunAbstract:Abstract The large number of animals that coexist in Soil without any clear niche differentiation has puzzled biologists for a long time. We investigated stable isotope ratios (15N/14N) in a diverse group of Soil Microarthropods, oribatid mites, to evaluate trophic niche differentiation. The natural variation of the stable isotopes 15N/14N was measured in 36 species/taxa from four beech and beech-oak forests. Signatures of δ15N formed a gradient spanning over 12 δ units suggesting that (a) different species occupy different trophic niches and (b) oribatid mites span three to four trophic levels. This study for the first time documented strong trophic niche differentiation in decomposer Microarthropods. The results suggest that trophic niche differentiation within taxonomic groups significantly contributes to the high diversity of Soil animal taxa.
Nico Eisenhauer - One of the best experts on this subject based on the ideXlab platform.
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Plant Soil feedbacks (PSF) as affected by Soil Microarthropods
2018Co-Authors: Eliska Kutakova, Simone Cesarz, Zuzana Münzbergová, Nico EisenhauerAbstract:Kuťáková, E.; Cesarz, S.; Münzberová, Z. & Eisenhauer, N. 2018. Soil Microarthropods alter the outcome of plant-Soil feedback experiments. Scientific Reports in press. DOI: 10.1038/s41598-018-30340-wSee the reference (Materials and Methods) for a detailed description of the PSF experiment and the individual measured variables.Plant data measured in the feedback phase refer to the mean values of plant individuals in each microcosm.Nematode counts refer to the numbers of individuals per gram Soil dry weight (the actual numbers of determined nematodes being extrapolated to the total nematode counts in the respective sample).
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Using structural equation modeling to test established theory and develop novel hypotheses for the structuring forces in Soil food webs
Pedobiologia, 2015Co-Authors: Yuanhu Shao, Nico Eisenhauer, Dima Chen, Weixin Zhang, Xueyong Pang, Guo-liang Xu, Shenglei FuAbstract:Abstract Understanding the structuring elements of Soil food webs is a major challenge for ecologists. Given the complex nature of Soil food webs, common treatment-based experiments and bivariate data analyses can only capture part of that complexity. Structural equation model (SEM) is a promising multivariate technique that may help understand direct and indirect relationships in complex Soil food webs. As bacterial and fungal energy channels, as well as bottom–up and top–down forces operate simultaneously, we used SEM to explore the complex interactions among multiple trophic levels in Soil food webs. Further, SEM allowed us to test established theory and to refine and derive hypotheses regarding the structuring forces of Soil food webs. We studied detritus-based Soil food webs in a 55-year-old subtropical Illicium verum forest ecosystem by sampling different important Soil food web components, including main Soil microbial groups, Soil nematodes, and Soil Microarthropods. The SEM results confirmed established theory by showing the central role of the fungal energy channel, and bottom–up effects were more important for the structure of the food web than top–down forces in the studied subtropical forest Soil. In addition, we could derive some novel and refined hypotheses regarding important feeding links in Soil food webs. For instance, we provide hypotheses on feeding preferences of different groups of Soil biota and on the strength of bottom–up versus top–down effects in forest Soil food webs. Overall, we highlight that SEM provides a framework to understand complex interactions and energy pathways in Soil food webs in a multivariate context, test established theory, and propose novel experimental tests.
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Global change belowground: Impacts of elevated CO2, nitrogen, and summer drought on Soil food webs and biodiversity
Global Change Biology, 2012Co-Authors: Nico Eisenhauer, Kally Worm, Simone Cesarz, Robert Koller, Peter B ReichAbstract:The world's ecosystems are subjected to various anthropogenic global change agents, such as enrichment of atmospheric CO2 concentrations, nitrogen (N) deposition, and changes in precipitation regimes. Despite the increasing appreciation that the consequences of impending global change can be better understood if varying agents are studied in concert, there is a paucity of multi-factor long-term studies, particularly on belowground processes. Herein, we address this gap by examining the responses of Soil food webs and biodiversity to enrichment of CO2, elevated N, and summer drought in a long-term grassland study at Cedar Creek, Minnesota, USA (BioCON experiment). We use structural equation modeling (SEM), various abiotic and biotic explanatory variables, and data on Soil microorganisms, protozoa, nematodes, and Soil Microarthropods to identify the impacts of multiple global change effects on drivers belowground. We found that long-term (13-year) changes in CO2 and N availability resulted in modest alterations of Soil biotic food webs and biodiversity via several mechanisms, encompassing Soil water availability, plant productivity, and – most importantly – changes in rhizodeposition. Four years of manipulation of summer drought exerted surprisingly minor effects, only detrimentally affecting belowground herbivores and ciliate protists at elevated N. Elevated CO2 increased microbial biomass and the density of ciliates, microarthropod detritivores, and gamasid mites, most likely by fueling Soil food webs with labile C. Moreover, beneficial bottom-up effects of elevated CO2 compensated for detrimental elevated N effects on Soil microarthropod taxa richness. In contrast, nematode taxa richness was lowest at elevated CO2 and elevated N. Thus, enrichment of atmospheric CO2 concentrations and N deposition may result in taxonomically and functionally altered, potentially simplified, Soil communities. Detrimental effects of N deposition on Soil biodiversity underscore recent reports on plant community simplification. This is of particular concern, as Soils house a considerable fraction of global biodiversity and ecosystem functions.
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the action of an animal ecosystem engineer identification of the main mechanisms of earthworm impacts on Soil Microarthropods
Pedobiologia, 2010Co-Authors: Nico EisenhauerAbstract:Abstract Non-trophic interactions are shaping Soil food web structure and functions. Particularly, the action of ecosystem engineers, such as earthworms, are likely to fundamentally impact the abiotic and biotic properties of their environment. The present study aimed to identify the main mechanisms through which earthworms belonging to varying ecological groups – epigeic, endogeic and anecic species – affect Soil Microarthropods by reviewing the literature on this topic and by performing meta-analyses. Earthworm ecological groups differed considerably in their impacts on Microarthropods, whereas effects did not vary significantly between microarthropod taxa at the habitat scale. Inconsistent impacts of epigeic species on Soil Microarthropods are most likely due to differences in earthworm densities. Effects can thus be positive in the case of moderate densities or negative in the case of high densities and associated distinct changes in the physical structure of the upper Soil organic layers. By contrast, impacts of endogeic earthworms appeared to be mainly negative and were primarily due to competition with Microarthropods for food resources. Consequently, negative impacts on Soil Microarthropods intensified with increasing earthworm density and biomass. This interaction between endogeic earthworms and Microarthropods is better referred to as amensalism due to the competitive predominance of earthworms. Impacts of anecic earthworm species differed significantly from that of endogeic ones; they were neutral at the habitat scale and positive on the microhabitat scale. Moreover, impacts were independent of earthworm densities due to the quasi-territorial behaviour of anecic earthworms. Positive effects were mainly attributed to the formation of stable microhabitats by anecic species; namely burrows/middens, rich in nutrients and microorganisms. The present study points to the relevance of the non-trophic biotic interactions that drive the composition of belowground food webs by identifying the most essential mechanisms underlying the impacts of animal ecosystem engineers on Soil Microarthropods. Moreover, as earthworms emerge as important biological invaders, the results of the present study may help to fully appreciate, estimate and model the consequences of this momentous global change phenomenon. Particularly, the spread of exotic epigeic and endogeic earthworm species likely threatens Soil microarthropod density, diversity and functions.
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invasion of a deciduous forest by earthworms changes in Soil chemistry microflora Microarthropods and vegetation
Soil Biology & Biochemistry, 2007Co-Authors: Nico Eisenhauer, Stephan Partsch, D Parkinson, Stefan ScheuAbstract:Abstract Ecosystems of northern North America existed without earthworm fauna until European settlers arrived and introduced European species. The current extent of invasion by some of these species, Lumbricus terrestris L., Octolasion tyrtaeum Savigny and Dendrobaena octaedra Savigny, into an aspen forest in the Canadian Rocky Mountains and the effects of the invasion on Soil chemistry, microflora, Soil Microarthropods and vegetation were investigated. Densities of earthworm species, Soil structure, plant coverage and abundance were determined along three transects starting at the edge of the forest. At locations with L. terrestris, litter was incorporated into the Soil, and where O. tyrtaeum was present, organic layers were mixed with mineral Soil layers. Organic layers disappeared almost entirely when both species occurred together. Carbon and nitrogen concentrations were reduced in organic layers in the presence of L. terrestris and O. tyrtaeum. Microbial biomass and basal respiration were reduced when L. terrestris and O. tyrtaeum were present, presumably due to resource competition and habitat destruction. Microarthropod densities and the number of microarthropod species were strongly reduced in the presence of O. tyrtaeum (−75% and −22%, respectively), probably through mechanical disturbances, increasing compactness of the Soil and resource competition. The coverage of some plant species was correlated with earthworm abundance, but the coverage of others was not. Despite harsh climatic conditions, the invasion of boreal forest ecosystems by mineral Soil dwelling earthworm species is proceeding and strongly impacts Soil structure, Soil chemistry, microorganisms, Soil Microarthropods and vegetation.
Martin Holmstrup - One of the best experts on this subject based on the ideXlab platform.
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Soil Microarthropods are only weakly impacted after 13 years of repeated drought treatment in wet and dry heathland Soils
Soil Biology & Biochemistry, 2013Co-Authors: Martin Holmstrup, Jesper Givskov Sorensen, Inger Kappel Schmidt, Pia L Nielsen, Sharon Mason, A Tietema, Andrew R Smith, Thomas Bataillon, Claus Beier, Bodil K EhlersAbstract:Studies of biological responses in the terrestrial environment to rapid changes in climate have mostly been concerned with aboveground biota, whereas less is known of belowground organisms. The present study focuses on mites and springtails of heathland ecosystems and how the microarthropod community has responded to simulated climate change in a long-term field experiment. Increased temperature and repeated drought was applied for 13 years to field plots located in Wales, The Netherlands and Denmark representing sites of contrasting climatic conditions with respect to precipitation and temperature. This approach provided an opportunity to study biological responses on a local (within sites) and regional scale. Warming treatments increasing night time temperature (0.3–1 °C higher than ambient at 5 cm Soil depth) had no detectable effects on the microarthropod communities. Increased intensity and frequency of drought had only weak persistent effects on springtail species composition, but practically no effect on major mite groups (Oribatida, Prostigmata or Mesostigmata) suggesting that ecosystem functions of Microarthropods may only be transiently impacted by repeated spring or summer drought.
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responses of springtail and mite populations to prolonged periods of Soil freeze thaw cycles in a sub arctic ecosystem
Applied Soil Ecology, 2007Co-Authors: Heidi Sjursen Konestabo, Anders Michelsen, Martin HolmstrupAbstract:The effect of temperature changes on Soil communities is an important aspect when estimating the effects of a predicted climate change. The aim of this investigation was to increase knowledge on how freeze-thaw cycles alter the Soil microarthropod community in the sub-arctic. The abundance of springtails and mites was investigated after three seasons of prolonged periods of freeze-thaw cycles in the field, and the presence or absence of migration barriers, at two different field sites. Dome shaped transparent plastic greenhouses were successfully used as a novel method to increase freeze-thaw cycle frequencies in the Soil. At a fellfield site, freeze-thaw treatment did not lead to significant differences in the five main Soil faunal groups, but increased abundance were seen in a number of separate taxa. There was no freeze-thaw treatment effect on Soil microbial biomass or Soil nutrients, although treatments interacted as inorganic N increased in the separate freeze-thaw and migration barrier treatments. By contrast, at a glade site responses were strong due to more pronounced increases in the number of freeze-thaw cycles. The highest numbers of Collembola after 2 years of treatment were found in the freeze-thaw plots, in combination with migration barriers. The freeze-thaw treatment here also resulted in more Oribatida, microbial biomass C and dissolved organic C. A common hypothesis is that an increased number of freeze-thaw cycles would result in elevated winter mortality in Microarthropods due to increased risk of inoculative freezing. However, we observed no increased mortality due to freeze-thaw events. Rather, there was a stimulation of Soil Microarthropods and microbial biomass, perhaps due to a prolonged period of microbial and faunal activity when the Soil is repeatedly frozen and thawed compared to a constantly frozen Soil.
Bodil K Ehlers - One of the best experts on this subject based on the ideXlab platform.
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Soil Microarthropods are only weakly impacted after 13 years of repeated drought treatment in wet and dry heathland Soils
Soil Biology & Biochemistry, 2013Co-Authors: Martin Holmstrup, Jesper Givskov Sorensen, Inger Kappel Schmidt, Pia L Nielsen, Sharon Mason, A Tietema, Andrew R Smith, Thomas Bataillon, Claus Beier, Bodil K EhlersAbstract:Studies of biological responses in the terrestrial environment to rapid changes in climate have mostly been concerned with aboveground biota, whereas less is known of belowground organisms. The present study focuses on mites and springtails of heathland ecosystems and how the microarthropod community has responded to simulated climate change in a long-term field experiment. Increased temperature and repeated drought was applied for 13 years to field plots located in Wales, The Netherlands and Denmark representing sites of contrasting climatic conditions with respect to precipitation and temperature. This approach provided an opportunity to study biological responses on a local (within sites) and regional scale. Warming treatments increasing night time temperature (0.3–1 °C higher than ambient at 5 cm Soil depth) had no detectable effects on the microarthropod communities. Increased intensity and frequency of drought had only weak persistent effects on springtail species composition, but practically no effect on major mite groups (Oribatida, Prostigmata or Mesostigmata) suggesting that ecosystem functions of Microarthropods may only be transiently impacted by repeated spring or summer drought.