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Jean-françois Ponge - One of the best experts on this subject based on the ideXlab platform.
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Chemical communication in springtails: a review of facts and perspectives
Biology and Fertility of Soils, 2019Co-Authors: Sandrine Salmon, Sylvie Rebuffat, Soizic Prado, Michel Sablier, Cyrille D’haese, Jean-françois PongeAbstract:The present knowledge on chemical communication in springtails (Collembola), one of the two most abundant invertebrate groups living in soil and environments in tight contact with soil (e.g. plant litter, moss), is reviewed here. Chemical communication in an environment where light is absent or dimmed becomes a prominent driver of trophic and non-trophic interactions between soil organisms at a time when better knowledge on the biological determinants of soil communities is required. Like insects and many other arthropods, Collembolan individuals of the same population intercommunicate by pheromones, which allow them signalling a risk or clustering in places favourable for feeding, mating, moulting and ovipositing. Olfaction is also used to select preferred food and mates. Researches so far conducted allowed discerning common trends in the role and chemical composition of odour blends used by Collembola. However, much more needs to be done before reaching straightforward conclusions about chemical communication issues at evolutionary and community levels, making this domain even more rewarding.
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Foraging patterns of soil springtails are impacted by food resources
Applied Soil Ecology, 2014Co-Authors: Matthieu Chauvat, Gabriel Perez, Jean-françois PongeAbstract:Movement of soil microarthropods associated to searching or foraging behaviour has received scanty attention and remained largely unexplored. However, rare studies on soil Collembola suggested that their exploratory behaviour is an important feature of population dynamics. In the current study based on a microcosm experiment, we tested the influence of food sources tied to a distant patch on the foraging behaviour of springtails. The microcosms consisted of five separate 5 cm sections bound together. Only the last part of the microcosms (section 5) differentiated the three treatments with no food (C), microflora (M) or microflora + plant (M + P). Collembola were introduced into the first section. The mean covered distance of total Collembolan differed between all the treatments. It continuously increased from 0.9 (±0.3) cm in C through 4.7 (±1.0) cm in M to 7.4 (±1.2) cm within M + P. Concomitantly, the mean covered distance was also influenced by the factor "life-form" with on average 7.3 cm covered by the epedaphic species which was 73.8% more than hemiedaphic and 82.5% more than euedaphic. Even if differences between life-forms were detected, our results also revealed differences of exploratory pattern between species belonging to the same life-form. Our study clearly shows that springtails are reactive to the quality of their environment, in particular food sources.
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Earthworms and Collembola relationships: effects of predatory centipedes and humus forms
Soil Biology and Biochemistry, 2005Co-Authors: Sandrine Salmon, Jean-jacques Geoffroy, Jean-françois PongeAbstract:Relationships between anecic earthworms (Lumbricus terrestris and Aporrectodea giardi) and the Collembolan species Heteromurus nitidus (Templeton, 1835), which is known to be attracted to earthworms, were investigated in an 8-week laboratory experiment. Our aims were (1) to assess whether earthworms influence the population dynamics of H. nitidus, and (2) to study pathways of influence and how earthworm effects are modified by humus forms and predators. Using microcosms with three defaunated humus forms, then provided with earthworms and predators, we intended to demonstrate that, amongst possible favourable effects of earthworms on springtail populations, earthworm activity may provide greater access and more pathways for springtails to explore soil and avoid predation. We expected that the effects of predators (centipedes) on the abundance of H. nitidus would increase from less (calcic mull) to more (moder) compact soil, and we hypothesized that earthworms would reduce predation pressure on H. nitidus by providing escape routes through increased macroporosity. Humus forms and earthworms only affected the population size of H. nitidus under high predation pressure, when Collembolan numbers were higher in calcic mull than in moder, and were increased by the presence of earthworms. These results corroborate the hypothesis that earthworms, by increasing soil macroporosity, improve the escape routes for Collembola and thus evade predation. In moder humus earthworms increased the density of H. nitidus whether predators were present or not, so we cannot exclude that earthworms were also directly beneficial to H. nitidus. However, the hypothesis of a functional relationship mediated by soil macroporosity seems relevant since it was supported by differences observed when considering body size. When two size classes were distinguished within populations of H. nitidus (1) the positive effect of earthworms in moder was observed only on larger Collembola (>1 mm), (2) the density of the larger Collembola was decreased by predation only in moder and not in mull, (3) the effects of predators on the smaller individuals were not influenced by the presence of earthworms whatever the humus form, and was not decreased by the presence of earthworms. Nevertheless, factors other than macroporosity may operate as the presence of earthworms in acidic mull led to an unexplained decrease in the abundance of small-sized H. nitidus.
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Changes in species assemblages and diets of Collembola along a gradient of metal pollution
Applied Soil Ecology, 2003Co-Authors: Servane Gillet, Jean-françois PongeAbstract:Springtails (Hexapoda: Collembola) are known to live in a wide range of soil conditions, but changes occurring in their communities under the influence of heavy metal pollution are still poorly documented. The present study was undertaken in order to discern main coenological trends along a gradient of metal pollution, downwind of a zinc smelter located in the north of France. Three sites were compared within an abandoned field planted with poplar 20 years ago. The total zinc content of the topsoil varied from 4000 to 35 000 mg/kg according to distance to the smelter outlet. Changes in humus forms (shift from mull to mor) and in the degree of opening of the poplar stand (mainly caused by death or stunting of planted trees in the vicinity of the smelter) explained most of the observed variation in abundance and species composition. Sun species living at the ground surface appeared at the most polluted sites where poplar declined and was replaced by a sward of metal-tolerant herb species. The increase in abundance of the whole Collembolan community was mainly due to Mesaphorura macrochaeta, the gut contents of which indicated that this species avoided the root mat and fed mainly in the mineral soil underneath. Shifts in food habits and/or in habitat were observed in several other common species, pointing to the importance of avoidance behaviour as a mechanism by which Collembolan species may endure heavy metal pollution.
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Interaction between humus form and herbicide toxicity to Collembola (Hexapoda)
Applied Soil Ecology, 2002Co-Authors: Jean-françois Ponge, Ipsa Bandyopadhyaya, Valérie MarchettiAbstract:Laboratory experiments were conducted using intact Collembolan communities, exposed to Madit D-(R) a phenylurea herbicide (active ingredient isoproturon). Effects were investigated using two distinct humus types, an acid Dysmoder and a neutral Eumull. Within two weeks, no effect of the herbicide was displayed by the Eumull population, while the Dysmoder population was stimulated. When animals were able to escape from the herbicide through a perforated wall separating two compartments filled with natural soil, the behavior of Collembolan communities exhibited interactive (non-additive) effects of humus type and herbicide application. The combination of an acid soil (supposedly providing greater tolerance to organic pollutants) with a neutral soil, increased biodiversity of Collembola, but caused the disappearance of some acido-sensitive species, pointing to complex relationships between pesticides, soils and soil organisms. Parallel experiments with single species demonstrated that at the recommended dose Madit D-(R) may cause avoidance effects, but no toxicity.
Sandrine Salmon - One of the best experts on this subject based on the ideXlab platform.
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Chemical communication in springtails: a review of facts and perspectives
Biology and Fertility of Soils, 2019Co-Authors: Sandrine Salmon, Sylvie Rebuffat, Soizic Prado, Michel Sablier, Cyrille D’haese, Jean-françois PongeAbstract:The present knowledge on chemical communication in springtails (Collembola), one of the two most abundant invertebrate groups living in soil and environments in tight contact with soil (e.g. plant litter, moss), is reviewed here. Chemical communication in an environment where light is absent or dimmed becomes a prominent driver of trophic and non-trophic interactions between soil organisms at a time when better knowledge on the biological determinants of soil communities is required. Like insects and many other arthropods, Collembolan individuals of the same population intercommunicate by pheromones, which allow them signalling a risk or clustering in places favourable for feeding, mating, moulting and ovipositing. Olfaction is also used to select preferred food and mates. Researches so far conducted allowed discerning common trends in the role and chemical composition of odour blends used by Collembola. However, much more needs to be done before reaching straightforward conclusions about chemical communication issues at evolutionary and community levels, making this domain even more rewarding.
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Shifts and linkages of functional diversity between above- and below-ground compartments along a flooding gradient
Functional Ecology, 2017Co-Authors: Corentin Abgrall, Matthieu Chauvat, Mickaël Hedde, Sandrine Salmon, Estelle Langlois, David Mouillot, Bruna Winck, Estelle ForeyAbstract:Trait-based approaches have the potential to reveal general and predictive relationships between organisms and ecosystem functioning. However, the mechanisms underlying the functional structure of communities are still unclear. Within terrestrial ecosystems, several studies have shown that many ecological processes are controlled by the interacting above- and below-ground compartments. However, few studies have used traits to reveal the functional relationships between plants and soil fauna. Mostly, research combining plants and soil fauna solely used the traits of one assemblage in predictive studies. Above-ground (plants) and below-ground (Collembola) compartments were sampled over a flooding gradient in northern France along the Seine River. First, we measured the effect of flooding on functional and taxonomic assembly within both communities. We then considered the linkages between plant and Collembolan species richness, community traits and assessed whether traits of both compartments converged at high flooding intensity (abiotic filtering) and diverged when this constraint is released (biotic filtering). Species richness of both taxa followed the same bell-shaped pattern along the gradient, while a similar significant pattern of functional richness was only observed for plants. Further analyses revealed a progressive shift from trait convergence to divergence for plants, but not for Collembola, as constraints intensity decreased. Instead, our results highlighted that Collembola traits were mainly linked to the variations in plant traits. This leads, within Collembola assemblages, to convergence of a subset of perception and habitat-related traits for which the relationship with plant traits was assessed. Synthesis. Using a trait-based approach, our study highlighted that functional relationships occur between above- and below-ground compartments. We underlined that functional composition of plant communities plays a key role in structuring Collembola assemblages in addition to the role of abiotic variables. Our study clearly shows that functional diversity provides a new approach to link the above- and below-ground compartments and might, therefore, be further considered when studying ecological processes at the interface between both compartments.
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Earthworms and Collembola relationships: effects of predatory centipedes and humus forms
Soil Biology and Biochemistry, 2005Co-Authors: Sandrine Salmon, Jean-jacques Geoffroy, Jean-françois PongeAbstract:Relationships between anecic earthworms (Lumbricus terrestris and Aporrectodea giardi) and the Collembolan species Heteromurus nitidus (Templeton, 1835), which is known to be attracted to earthworms, were investigated in an 8-week laboratory experiment. Our aims were (1) to assess whether earthworms influence the population dynamics of H. nitidus, and (2) to study pathways of influence and how earthworm effects are modified by humus forms and predators. Using microcosms with three defaunated humus forms, then provided with earthworms and predators, we intended to demonstrate that, amongst possible favourable effects of earthworms on springtail populations, earthworm activity may provide greater access and more pathways for springtails to explore soil and avoid predation. We expected that the effects of predators (centipedes) on the abundance of H. nitidus would increase from less (calcic mull) to more (moder) compact soil, and we hypothesized that earthworms would reduce predation pressure on H. nitidus by providing escape routes through increased macroporosity. Humus forms and earthworms only affected the population size of H. nitidus under high predation pressure, when Collembolan numbers were higher in calcic mull than in moder, and were increased by the presence of earthworms. These results corroborate the hypothesis that earthworms, by increasing soil macroporosity, improve the escape routes for Collembola and thus evade predation. In moder humus earthworms increased the density of H. nitidus whether predators were present or not, so we cannot exclude that earthworms were also directly beneficial to H. nitidus. However, the hypothesis of a functional relationship mediated by soil macroporosity seems relevant since it was supported by differences observed when considering body size. When two size classes were distinguished within populations of H. nitidus (1) the positive effect of earthworms in moder was observed only on larger Collembola (>1 mm), (2) the density of the larger Collembola was decreased by predation only in moder and not in mull, (3) the effects of predators on the smaller individuals were not influenced by the presence of earthworms whatever the humus form, and was not decreased by the presence of earthworms. Nevertheless, factors other than macroporosity may operate as the presence of earthworms in acidic mull led to an unexplained decrease in the abundance of small-sized H. nitidus.
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The impact of earthworms on the abundance of Collembola: improvement of food resources or of habitat?
Biology and Fertility of Soils, 2004Co-Authors: Sandrine SalmonAbstract:I assessed the direct influence of earthworm excretions, and the impact of earthworms through their action on the soil structure (increased macroporosity), on the population dynamics of the Collembolan species Heteromurus nitidus . The intestinal content of Collembola arising from cultures on different soil types was observed, and two experimental cultures of H. nitidus were run: (1) a culture performed on an inert substrate supplied either with earthworm casts or with soil as food resource, (2) an experiment using microcosms with cores of two humus forms (moder and calcic mull), in the presence or absence of earthworms. The observation of gut contents revealed that H. nitidus feeds on excrements, the composition of which (ratio organic matter/mineral matter) varies according to the humus form where it lived. Slightly aged (10–15 days) organo-mineral casts of earthworms appeared to be a better food than calcic mull aggregates or organic material from moder. Densities of H. nitidus cultured in cores of calcic mull were higher than in moder, except when cores of moder were inhabited by an anecic earthworm for 2 months. The humus form strongly influenced populations of H. nitidus , firstly because densities of predators were higher in moder than in calcic mull, and probably also because of soil macroporosity. It was concluded that earthworms would affect predation on H. nitidus by creating a network of interconnected macropores in which Collembola can move and find shelter.
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Earthworm excreta attract soil springtails: laboratory experiments on Heteromurus nitidus (Collembola : Entomobryidae)
Soil Biology and Biochemistry, 2001Co-Authors: Sandrine Salmon, Jean-françois PongeAbstract:Microarthropods are often found more abundantly in soils with earthworms than in soils without. Earthworms probably create a favourable environment for microarthropods but few studies have aimed to explain this earthworm effect. The soil Collembolan (Hexapoda) Heteromurus nitidus, living in soils at pH > 5 only and thus rich in earthworms, is particularly attracted by earthworms in humus cores. The effect of earthworms on the distribution of H. nitidus can be mediated either by direct contact or by odour perception. Two experimental designs were used to determine the pathway of attraction. The first set of experiments studied the effect of direct contact with earthworm excreta on the distribution of H. nitidus. The mixture of urine and mucus of the lumbricid earthworms Aporrectodea giardi and Alollobophora chlorotica significantly attracted H. nitidus as compared to deionized water while fresh earthworm casts were not preferred to calcic mull made of older casts. The same experiment involving direct contact with mucus and methyl blue showed that Collembola sucked on mucus/urine, indicating that the interaction of Collembola and earthworms was at least partly trophic. The second experiment demonstrated that H. nitidus was attracted by the odour of Aporrectodea giardi at short distance. The odour of excreta (mucus, urine and casts) of Aporrectodea giardi also attracted H. nitidus but this attraction was weaker and did not occur constantly, possibly due to interactions with light and aggregation pheromones. We conclude that the prominent pathway by which earthworms could attract H. nitidus in the field is through direct contact with earthworm mucus and urine. The acid-intolerant distribution of this species in the field could be partly explained by a trophic interaction with some earthworm species.
Matthieu Chauvat - One of the best experts on this subject based on the ideXlab platform.
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Functional Collembolan assemblages induce different plant responses in Lolium perenne
Plant and Soil, 2020Co-Authors: Bruna R. Winck, Matthieu Chauvat, Sekou F. M. Coulibaly, Mathieu Santonja, Enilson Luiz Saccol De Sá, Estelle ForeyAbstract:Background and aims Interactions between functional groups of soil fauna and plants are poorly explored although they drive functional processes such as nutrient availability and therefore plant performance. Here, we investigated the separated and combined effects of two Collembolan functional groups on soil properties and growth of Lolium perenne , a typical grass species from temperate grasslands. Methods Under microcosm conditions, we established four treatments based on the presence and combination of two Collembolan functional groups: (1) control without Collembola; (2) epedaphic species; (3) euedaphic species; (4) epedaphic + euedaphic species. After five months of experiment, we measured the effect of those treatments on both nutritional and morphological variables of L. perenne and on soil properties. Results Collembolan presence stimulated plant performance. Individuals of L. perenne growing with euedaphic species presented higher numbers of leaves and nutrient contents compared with individuals growing with epedaphic species. Further, the combination of both Collembolan functional groups enhanced plant performance and soil nutrient availability, demonstrating that a functionally diversified soil fauna assemblage cause overyielding of ecological processes. Conclusion Our results provide evidences of complementarity interactions between different functional groups of soil fauna causing overyielding of primary production.
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Shifts and linkages of functional diversity between above- and below-ground compartments along a flooding gradient
Functional Ecology, 2017Co-Authors: Corentin Abgrall, Matthieu Chauvat, Mickaël Hedde, Sandrine Salmon, Estelle Langlois, David Mouillot, Bruna Winck, Estelle ForeyAbstract:Trait-based approaches have the potential to reveal general and predictive relationships between organisms and ecosystem functioning. However, the mechanisms underlying the functional structure of communities are still unclear. Within terrestrial ecosystems, several studies have shown that many ecological processes are controlled by the interacting above- and below-ground compartments. However, few studies have used traits to reveal the functional relationships between plants and soil fauna. Mostly, research combining plants and soil fauna solely used the traits of one assemblage in predictive studies. Above-ground (plants) and below-ground (Collembola) compartments were sampled over a flooding gradient in northern France along the Seine River. First, we measured the effect of flooding on functional and taxonomic assembly within both communities. We then considered the linkages between plant and Collembolan species richness, community traits and assessed whether traits of both compartments converged at high flooding intensity (abiotic filtering) and diverged when this constraint is released (biotic filtering). Species richness of both taxa followed the same bell-shaped pattern along the gradient, while a similar significant pattern of functional richness was only observed for plants. Further analyses revealed a progressive shift from trait convergence to divergence for plants, but not for Collembola, as constraints intensity decreased. Instead, our results highlighted that Collembola traits were mainly linked to the variations in plant traits. This leads, within Collembola assemblages, to convergence of a subset of perception and habitat-related traits for which the relationship with plant traits was assessed. Synthesis. Using a trait-based approach, our study highlighted that functional relationships occur between above- and below-ground compartments. We underlined that functional composition of plant communities plays a key role in structuring Collembola assemblages in addition to the role of abiotic variables. Our study clearly shows that functional diversity provides a new approach to link the above- and below-ground compartments and might, therefore, be further considered when studying ecological processes at the interface between both compartments.
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Forest plant community as a driver of soil biodiversity. A large-scale assessment on Collembolan assemblages through stand density experimental manipulation
2014Co-Authors: Ludovic Henneron, M. Aubert, F. Bureau, Y. Dumas, François Ningre, Sandrine Perret, C. Richter, Philippe Balandier, Matthieu ChauvatAbstract:Plant-soil interactions are increasingly recognized to play a major role for terrestrial ecosystems functioning. However, few studies to date have focused on long-term dynamic ecosystems such as forests. Indeed, forest ecosystems are vertically stratified by multiple vegetation strata and the canopy cover manipulation through contrasted stand density management strategies could alter the overall architecture of forest plant community. Very little is known about the cascading effect on soil biodiversity and ecosystem function such as litter decomposition. The aim of this study was to assess the response of a major group of soil fauna, namely Collembola, to oak stand density experimental manipulation. A total of 33 stands distributed over a large geographic area were studied covering a wide gradient of stand density, i.e. stand basal area from 2.5 to 43.7 m2.ha-1, stand age, i.e. 18 to 171-year-old, and pedoclimatic context conditions. Our results shown that the response of Collembolan assemblages to stand density was highly dependent on stand age. Indeed, Collembolan abundance and diversity tend to decrease with stand density reduction in young stands while no response was observed in old stands. Further, a substantial shift of Collembolan species composition was observed within young stands and this was strongly associated with contrasted responses among functional groups. Hemiedaphic and euedaphic species abundance and diversity were strongly depleted by stand density reduction whereas epedaphic abundance was unaffected. In contrast, epedaphic diversity tended to be enhanced by stand density reduction. Patterns of Collembolan assemblages response to stand density was consistent among pedoclimatic contexts, i.e. mull vs moder. Exploratory analysis using causal diagrams, i.e. path analyses, highlights that those changes were mainly related to understorey vegetation, microclimatic and soil pH condition alterations. These changes of Collembolan assemblages could have important functional implications, especially on microbial respiration process through their grazing activities.
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Foraging patterns of soil springtails are impacted by food resources
Applied Soil Ecology, 2014Co-Authors: Matthieu Chauvat, Gabriel Perez, Jean-françois PongeAbstract:Movement of soil microarthropods associated to searching or foraging behaviour has received scanty attention and remained largely unexplored. However, rare studies on soil Collembola suggested that their exploratory behaviour is an important feature of population dynamics. In the current study based on a microcosm experiment, we tested the influence of food sources tied to a distant patch on the foraging behaviour of springtails. The microcosms consisted of five separate 5 cm sections bound together. Only the last part of the microcosms (section 5) differentiated the three treatments with no food (C), microflora (M) or microflora + plant (M + P). Collembola were introduced into the first section. The mean covered distance of total Collembolan differed between all the treatments. It continuously increased from 0.9 (±0.3) cm in C through 4.7 (±1.0) cm in M to 7.4 (±1.2) cm within M + P. Concomitantly, the mean covered distance was also influenced by the factor "life-form" with on average 7.3 cm covered by the epedaphic species which was 73.8% more than hemiedaphic and 82.5% more than euedaphic. Even if differences between life-forms were detected, our results also revealed differences of exploratory pattern between species belonging to the same life-form. Our study clearly shows that springtails are reactive to the quality of their environment, in particular food sources.
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Establishment of bioenergy crops on metal contaminated soils stimulates belowground fauna
Biomass and Bioenergy, 2014Co-Authors: Matthieu Chauvat, Mickaël Hedde, Gabriel Perez, Isabelle LamyAbstract:Soils of contaminated agrosystems represent potential arable land surfaces for the production of non-alimentary crops. The aim of this study is to monitor changes in belowground biodiversity (Collembola), potentially occurring following establishment of perennial biomass crop systems on contaminated agricultural land. We selected, within an agricultural trial, two different biomass crops, miscanthus (Miscanthus x giganteus) and switchgrass (Panicum virgatum) and an annual wheat crop (Triticum sp.) used as a control. About 20-fold more individuals were found under miscanthus and switchgrass than under wheat. The highest mean number of species was found under miscanthus being 30% greater than in switchgrass and 424% than in annual wheat. Furthermore, abundance and species richness of the three Collembolan life-forms (epedaphic, hemiedaphic, and euedaphic) differed between the crops leading to distinctly different assemblages. On metal contaminated soils, perennial bioenergy crops have the potential to increase belowground faunal diversity and abundance with the identity of crops as a critical factor driving soil animal assemblages.
Jérôme Cortet - One of the best experts on this subject based on the ideXlab platform.
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Contrasting homogenization patterns of plant and Collembolan communities in urban vegetable gardens
Urban Ecosystems, 2019Co-Authors: Sophie Joimel, Christophe Schwartz, Noëlie Maurel, Benjamin Magnus, Nathalie Machon, Jérémie Bel, Jérôme CortetAbstract:Urban biotic homogenization is one of the foremost challenges for conservation of biodiversity in urban green areas. Urban gardening is a common practice in many industrialised and developing countries. The ability of urban vegetable gardens to support biodiversity, however, has yet to be studied in depth. To investigate the responses of flora and soil fauna to urbanization, we surveyed the taxonomic and functional composition of plant and Collembolan communities, in addition to soil parameters, in 15 urban vegetable gardens across three large French cities. The vegetation was identified in six plots of 1 × 1 m in each urban vegetable garden and Collembolan were extracted from one intact soil core sampled in the center of each plot (5 cm depth, 6 cm diameter). We found contrasting effects of urbanization on plants and Collembola biodiversity. The taxonomic and functional composition of the soil fauna was more similar within cities than among cities, which was driven by similarities in soil parameters. In contrast, plant communities were functionally similar among cities. Understanding the effects of urbanization on soil biodiversity could have implications for the management of urban ecosystems, in particular that of urban soils.
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Urban and industrial land uses have a higher soil biological quality than expected from physicochemical quality
Science of the Total Environment, 2017Co-Authors: Sophie Joimel, Christophe Schwartz, Mickaël Hedde, Sayuri Kiyota, Paul Henning Krogh, Johanne Nahmani, Guenola Peres, Alan Vergnes, Jérôme CortetAbstract:Despite their importance both in soil functioning and as soil indicators, the response of microarthropods to various land uses is still unclear. The aim of this study is to assess the effect of land use on microarthropod diversity and determine whether a soil's biological quality follows the same physicochemical quality-based gradient from forest, agriculture-grassland, agriculture-arable land, vineyards, urban vegetable gardens to urban, industrial, traffic, mining and military areas. A database compiling the characteristics of 758 communities has been established. We calculated Collembola community indices including: species richness, Pielou's evenness index, Collembolan life forms, the abundance of Collembola and of Acari, the Acari/Collembola abundance ratio, and the Collembolan ecomorphological index. Results show that agricultural land use was the most harmful for soil microarthropod biodiversity, whilst urban and industrial land uses give the same level of soil biological quality as forests do. Furthermore, differences between the proportions of Acari and ecomorphological groups were observed between land uses. This study, defining soil microarthropod diversity baselines for current land uses, should therefore help in managing and preserving soil microarthropod biodiversity, especially by supporting the preservation of soil quality.
C A M Van Gestel - One of the best experts on this subject based on the ideXlab platform.
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bioavailability and ecological effects of cadmium on folsomia candida willem in an artificial soil substrate as influenced by ph and organic matter
Applied Soil Ecology, 1997Co-Authors: T Crommentuijn, A Doornekamp, C A M Van GestelAbstract:The validity of the pore-water hypothesis was studied by determining the bioavailability and toxicity of cadmium to the Collembolan species Folsomia candida, in artificial soils with different pH and different organic matter content. Cadmium solubility, cadmium accumulation by individuals and effects on survival, growth and population-increase were determined. Water soluble cadmium concentrations, at comparable total soil concentrations, increased with decreasing pH and decreasing organic matter content of the soil. No consistent pattern in accumulation of cadmium by Collembola was found for the different treatments. The variation in LC50 values and EC50 values for growth and population increase, increased when effects were expressed as soluble concentrations instead of total concentrations in the soil. When expressed as internal concentrations the variation decreased except for population increase at different pHs. It may, therefore, be concluded that the bioavailability of cadmium to F. candida is not predicted by the water soluble concentration and that Collembolan sensitivity is not only determined by the internal cadmium concentration but also by differences in soil characteristics. This hampers a straight-forward prediction of metal toxicity using the pore-water hypothesis.
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the influence of soil moisture content on the bioavailability and toxicity of cadmium for folsomia candida willem Collembola isotomidae
Ecotoxicology and Environmental Safety, 1997Co-Authors: C A M Van Gestel, A M F Van DiepenAbstract:Abstract For Collembola living in the upper soil and litter layers, soil moisture is a primary factor for survival. In addition, a shortage or surplus of moisture might interact with other stress factors, such as persistent pollutants. The aim of this study therefore was to investigate the response of the Collembolan species Folsomia candida to cadmium at different soil moisture contents. Tests were performed in an artificial soil substrate at soil moisture levels of 25, 35, 45, and 55%, corresponding with 74, 103, 132, and 162% of field capacity, respectively. Cadmium sorption to the soils, estimated from water-soluble concentrations, was not significantly affected by soil moisture content. Significant effects of soil moisture content were found for the toxicity of cadmium on body weight of F. candida after 4 and 6 weeks. EC 50 s did, however, not differ by more than a factor of 2. Reproduction in the controls was strongly affected by soil moisture content, but EC 50 s for the effect of cadmium on reproduction did not differ for the different moisture levels. Cadmium concentrations in the animals were not significantly affected by soil moisture content. From this study it can be concluded that, within the range chosen, soil moisture content does not have a great influence on the bioavailability and toxicity of cadmium for the Collembolan F. candida.