Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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Impact of trophic ecologies on the whereabouts of nematodes in soil
Quist, Casper W. - \ 2017
Wageningen University. Promotor(en): Jaap Bakker, co-promotor(en): Hans Helder. - Wageningen : Wageningen University - ISBN 9789463430814 - 129
nematoda - spatial distribution - soil fauna - biota - trophic levels - food webs - soil ecology - soil biology - farming systems - soil types (ecological) - geostatistics - ruimtelijke verdeling - bodemfauna - trofische graden - voedselwebben - bodemecologie - bodembiologie - bedrijfssystemen - bodemtypen (ecologisch) - geostatistiek

Soil life is highly diverse, and ecologically intricate due to myriad of biotic interactions that take place. Terrestrial nematodes have a high potential to serve as an effective and policy-relevant indicator group for ecosystem functioning and soil biodiversity. The work described in this thesis contributed to the robust mapping of nematode communities at scales relevant in both agronomic and environmental contexts. The overarching aim of the work described in this thesis was to contribute to a sound exploration of the potential of nematode communities as an indicator group for the biological condition of soils. Therefore, the distributions of a wide range of nematode taxa were studied, within and between trophic groups and in soils conditioned by various plant species and/or farming systems.

In Chapter 2 nematode taxon-specific qPCR assays were used to pinpoint responses of nematode communities to invasive plant species Solidago gigantea in two invaded ecosystems: semi-natural grasslands and riparian floodplains. Nematode communities and fungal biomass were examined in adjacent invaded and uninvaded patches. The dominant presence of the invasive plant causes a decrease of plant species-richness and diversity, and an about twofold increase of fungal biomass. Only the density of a single group of fungivorous nematodes (Aphelenchoididea) increased, whereas the densities of two other, phylogenetically distinct lineages of fungivorous nematodes, Aphelenchidae and Diphtherophoridae, were unaffected by the local increase in fungal biomass. Apparently S. gigantea induces a local asymmetric boost of the fungal community, and only Aphelenchoididae were able to benefit from this change induced by the invasive plant.

In Chapter 3 the outcome is shown of a test whether farming system effects are mirrored in compositional changes in nematode communities. The long-term impact of three farming systems (conventional, integrated and organic) on nematode communities was investigated at the Vredepeel, an experimental farm in the southeastern part of The Netherlands. The results showed that organic farming causes specific shifts in nematode community composition, exceeding the usually large crop-related assemblage shifts. Strongest effects were observed for the (putative) bacterivore Prismatolaimus, which was relatively common in organic fields and nearly absent in conventional and integrated farming. A reverse effect was observed for Pristionchus; this necromenic bacterivore and facultative predator made up about 7 – 21% of the total nematode community in integrated and conventional farming, whereas it was nearly absent from organic fields. The observed farming system effects suggest that specific nematode taxa might be indicative for the impact of farming practices on soil biota. Knowledge of spatial distribution patterns of soil organisms with distinct trophic preferences will contribute to our understanding of factors that maintain and regulate soil biodiversity, and is essential information to design soil sampling strategies with predictable accuracies.

Chapter 4 deals with microscale patchiness of 45 nematode taxa (at family, genus or species-level) in arable fields and semi-natural grasslands, on marine clay, river clay or sandy soils. Contrary to our expectations, an increase of the number of cores per composite sample above 3, did not result in more accurate detection for any of the taxa under investigation (range of number of cores per composite sample: 3, 6, 12 or 24). Neither system nor soil type did influence microscale distribution. The insights in the spatial distribution of nematodes at microscale presented here, sheds light on the impact of trophic preferences on the spatial distribution of individual nematode taxa, and will allow for the design of statistically sound soil sampling strategies.

Chapter 5 shows belowground distribution patterns of 48 nematode taxa in 12 visually homogeneous fields (each 100 x 100 m) on three soil types (marine clay, river clay and sand) and two land-use types (arable and natural grasslands) across the Netherlands. Over 35,000 nematode-taxon specific qPCR assays allowed us to quantitative analyse nematode taxa at family, genus or species level in over 1,200 soil samples. A sampling scheme was optimized for Bayesian geostatistical analysis (Integrated nested Laplace approximations; INLA). Multivariate analysis show soil type and land-use related differences in the nematode community composition, which underline the effects of environmental filtering and niche partitioning of nematodes. All individual nematode taxa together show a wide range of degrees of spatial variabilities were found (expressed by the range-parameter and the spatial variance parameter (s2spatial). No general effects were detected of soil characteristics or nematode traits (cp-value, trophic group, weight) on the spatial distribution parameters. The relatively high percentages of unexplained spatial variability – 92.5% of the variation for the range-parameter and 74% for spatial variance (s2spatial) – point at a major role of stochasticity for variability of nematode densities within fields. This study adds empirical evidence that distribution patterns of terrestrial nematodes, in areas without noticeable gradients, are driven by neutral / stochastic processes, within the boundaries set by the environment.

In the final Chapter 6, I discuss the opportunities and challenges of the use of molecular tools in soil ecological research, the impact of trophic preferences on the whereabouts of nematodes, the use of nematode communities as indicator for soil condition and how this might be developed and applied to facilitate more sustainable ecosystem management.

Gehalte aan zware metalen in biota op stort- en referentielocaties in de Oosterschelde
Glorius, S.T. ; Heuvel-Greve, M.J. van den - \ 2016
IMARES (Rapport / IMARES C081/16) - 32 p.
heavy metals - mytilus edulis - crassostrea gigas - biota - sampling - eastern scheldt - zware metalen - bemonsteren - oosterschelde
Dit rapport beschrijft de resultaten van de metaalanalyses in mosselen Mytilus edulis en Japanse oesters Crassostrea gigas bemonsterd op verschillende locaties in de Oosterschelde. Hierbij wordt ingegaan op de jaarlijkse variatie in metaalconcentratie in mossel- en oesterweefsel en verschillen tussen type stort en referentielocaties en worden gehalten getoetst aan geldende milieukwaliteitsnormen.
Monitoring vooroeververdediging Oosterschelde en Westerschelde 2014
Tangelder, M. ; Heuvel-Greve, M.J. van den; Kluijver, M. de; Glorius, S.T. ; Jansen, H.M. - \ 2015
Yerseke : IMARES (Rapport / IMARES C102/15) - 141
oeverbescherming van rivieren - dijken - steenwerk - staal - aquatische ecosystemen - biota - metalen - ecotoxicologie - oosterschelde - westerschelde - nederland - riverbank protection - dykes - stonework - steel - aquatic ecosystems - metals - ecotoxicology - eastern scheldt - western scheldt - netherlands
Rijkswaterstaat bestort de vooroevers voor de dijken in de Ooster- en Westerschelde om de waterveiligheid te kunnen blijven waarborgen. Voor deze bestortingen wordt gebruik gemaakt van staalslakken, breukstenen en zeegrind. Om de gevolgen van het bestorten voor het plaatselijke onderwaterleven inzichtelijk te maken wordt monitoring uitgevoerd door IMARES in opdracht van Rijkswaterstaat. Hierbij wordt onderzoek gedaan naar hard substraat soorten (planten en dieren gevestigd op de harde oever), zacht substraat soorten (dieren die in het sediment op de vooroever leven) en mogelijke uitloging van zware metalen vanuit de vooroeverbestorting naar planten en dieren
Plant–soil feedbacks of exotic plant species across life forms: a meta-analysis
Meisner, A. ; Hol, W.H.G. ; Boer, W. de; Krumins, J.A. ; Wardle, D.A. ; Putten, W.H. van der - \ 2014
Biological Invasions 16 (2014)12. - ISSN 1387-3547 - p. 2551 - 2561.
serpentine grassland - invasive plants - native range - biota - communities - pathogens - traits - ecosystems - contribute - dependence
Invasive exotic plant species effects on soil biota and processes in their new range can promote or counteract invasions via changed plant–soil feedback interactions to themselves or to native plant species. Recent meta-analyses reveale that soil influenced by native and exotic plant species is affecting growth and performance of natives more strongly than exotics. However, the question is how uniform these responses are across contrasting life forms. Here, we test the hypothesis that life form matters for effects on soil and plant–soil feedback. In a meta-analysis we show that exotics enhanced C cycling, numbers of meso-invertebrates and nematodes, while having variable effects on other soil biota and processes. Plant effects on soil biota and processes were not dependent on life form, but patterns in feedback effects of natives and exotics were dependent on life form. Native grasses and forbs caused changes in soil that subsequently negatively affected their biomass, whereas native trees caused changes in soil that subsequently positively affected their biomass. Most exotics had neutral feedback effects, although exotic forbs had positive feedback effects. Effects of exotics on natives differed among plant life forms. Native trees were inhibited in soils conditioned by exotics, whereas native grasses were positively influenced in soil conditioned by exotics. We conclude that plant life form matters when comparing plant–soil feedback effects both within and between natives and exotics. We propose that impact analyses of exotic plant species on the performance of native plant species can be improved by comparing responses within plant life form.
Partitioning of perfluorooctanesulfonate and perfluorohexanesulfonate in the aquatic environment after an accidental release of aqueous film forming foam at Schiphol Amsterdam Airport
Kwadijk, C.J.A.F. ; Kotterman, M.J.J. ; Koelmans, A.A. - \ 2014
Environmental Toxicology and Chemistry 33 (2014)8. - ISSN 0730-7268 - p. 1761 - 1765.
perfluorinated surfactants - perfluoroalkyl acids - firefighting foam - organic-compounds - water - sulfonate - sediment - sorption - biota - fate
In the summer of 2008, an accidental release of Aqueous Film Forming Foam (AFFF) took place at Schiphol Amsterdam Airport (The Netherlands). After the release, water, fish and sediment samples were collected and analyzed for perfluoroalkyl sulfonates (PFSA). In situ perfluorooctane sulfonate (PFOS) KD values, BAF and BSAF values showed a remarkable agreement among reference and impacted sites, 10 weeks after the incident as well as after 3 years.
Biochars produced from individual grassland species differ in their effect on plant growth
Voorde, T.F.J. van de; Noppen, F. van; Nachenius, R.W. ; Prins, W. ; Mommer, L. ; Bezemer, T.M. ; Groenigen, J.W. van - \ 2014
Basic and Applied Ecology 15 (2014)1. - ISSN 1439-1791 - p. 18 - 25.
litter decomposition - soil - chemistry - jacobaea - vulgaris - quality - traits - rates - biota
Biochar, pyrolyzed biomass, has been shown to be a promising way to improve plant productivity and soil quality. Biochar characteristics and its effect on plant performance depend strongly on the type of feedstock from which it is made. However, whether biochars produced from individual grassland species differ in their characteristics and effects on plant growth when applied to soil is poorly understood. The aim of this study was to examine how soil application of pyrolyzed and non-pyrolyzed biomass originating from different grassland species influences plant performance. We measured the growth of the forb Jacobaea vulgaris in soil amended with pyrolyzed or non-pyrolyzed biomass of seven different plant species, and in control soil without amendments. The characteristics (nutrient content, C:N) and effects on plant growth of both pyrolyzed and non-pyrolyzed biomass differed significantly between species from which the biomass originated (‘feedstock species’). For most feedstock species there was no relationship between the effects that the pyrolyzed and the non-pyrolyzed biomass had on plant performance. Our results show that pyrolyzed grassland species differ in their characteristics and their effect on plant growth when amended to soil. This shows that it is important to test what the effect of pyrolysing a chosen feedstock is on a species before applying it on a larger scale and that potentially biochar with predefined effects could be designed for specific purposes.
Selective alteration of soil food web components by invasive Giant goldenrod (Solidago gigantea) in two distinct habitat types
Quist, C.W. ; Vervoort, M.T.W. ; Megen, H.H.B. van; Gort, G. ; Bakker, J. ; Putten, W.H. van der; Helder, J. - \ 2014
Oikos 123 (2014)7. - ISSN 0030-1299 - p. 837 - 845.
exotic plant invasions - nematode communities - alien plants - ergosterol - biota - diversity - biodiversity - extraction - canadensis - feedbacks
Apart from relatively well-studied aboveground effects, invasive plant species will also impact the soil food web. So far, most research has been focusing on primary decomposers, while studies on effects at higher trophic levels are relatively scarce. Giant goldenrod Solidago gigantea, native to North America, is a widespread and common invasive species in most European countries. We investigated its impact on plant communities and on multiple trophic levels of the soil food web in two contrasting habitats: riparian zones and semi-natural grasslands. In 30 pairs of invaded and uninvaded plots, floristic composition, pH, fungal biomass and the densities of 11 nematode taxa were determined by using a quantitative PCR-based method. In the two habitats, the invader outcompeted both rare and dominant plant species. Belowground, S. gigantea invasion reduced pH, increased overall fungal biomass as well as the density of a single lineage of fungivorous nematodes, the family Aphelenchoididae. The densities of two other, phylogenetically distinct lineages of fungivorous nematodes, Aphelenchidae and Diphtherophoridae, were unaffected by the local increase in fungal biomass. Apparently this plant species induces a local asymmetric boost of the fungal community, and only Aphelenchoididae were able to benefit from this invader-induced change. The alternative explanation – the results are explained by a subtle, S. gigantea-induced 0.1–0.2 units decrease of pH – seems unlikely, as pH optima for nematode taxa are relatively broad. Thus, apart from readily observable aboveground effects, the invasive plant species S. gigantea affects fungal biomass as well as a specific part of the fungivorous nematode community in a soil type-independent manner.
Consequences of plant–soil feedbacks in invasion
Suding, K.N. ; Harpole, W.S. ; Fukami, T. ; Kulmatiski, A. ; MacDougall, A.S. ; Stein, C. ; Putten, W.H. van der - \ 2013
Journal of Ecology 101 (2013)2. - ISSN 0022-0477 - p. 298 - 308.
microbial community structure - acacia-longifolia - biota - restoration - pathogens - dynamics - ecology - accumulation - invasiveness - coexistence
1. Plant species can influence soil biota, which in turn can influence the relative performance of plant species. These plant–soil feedbacks (PSFs) have been hypothesized to affect many community-level dynamics including species coexistence, dominance and invasion. 2. The importance of PSFs in exotic species invasion, although widely hypothesized, has been difficult to determine because invader establishment necessarily precedes invader-mediated PSFs. Here, we combine a spatial simulation model of invasion that incorporates PSFs with a meta-analysis that synthesizes published case studies describing feedbacks between pairs of native and exotic species. 3. While our spatial model confirmed the link between positive soil feedbacks (‘home’ advantage) for exotic species and exotic species spread, results were dependent on the initial abundance of the exotic species and the equivalence of dispersal and life history characteristics between exotic and native species. 4. The meta-analysis of 52 native–exotic pairwise feedback comparisons in 22 studies synthesized measures of native and exotic performance in soils conditioned by native and exotic species. The analysis indicated that the growth responses of native species were often greater in soil conditioned by native species than in soil conditioned exotic species (a ‘home’ advantage). The growth responses of exotic species were variable and not consistently related to species soil-conditioning effects. 5. Synthesis. Overlaying empirical estimates of pairwise PSFs with spatial simulations, we conclude that the empirically measured PSFs between native and exotic plant species are often not consistent with predictions of the spread of exotic species and mono-dominance. This is particularly the case when exotic species are initially rare and share similar dispersal and average fitness characteristics with native species. However, disturbance and other processes that increase the abundance of exotic species as well as the inclusion of species dispersal and life history differences can interact with PSF effects to explain the spread of invasive species
Simultaneous extraction and determination of HBCD isomers and TBBPA by ASE and LC-MSMS in fish
Dam, G. ten; Pardo, O. ; Traag, W.A. ; Lee, M.K. van der; Peters, R.J.B. - \ 2012
Journal of Chromatography. B, Analytical technologies in the biomedical and life sciences 898 (2012). - ISSN 1570-0232 - p. 101 - 110.
brominated flame retardants - enantiomer-specific accumulation - tandem mass-spectrometry - hexabromocyclododecane diastereoisomers - tetrabromobisphenol - biota
Since the EFSA enquired a call for data for TBBPA and HBCD in 2009, the analytical determination of these compounds in food became of regulatory interest. Therefore, a method for the simultaneous determination of TBBPA and the three major HBCD stereoisomers was developed. Conventional techniques like soxhlet, ASE, GPC, sulphuric acid digestion, and acidified silica SPE are generally used in sample pre-treatment while detection is mostly performed by LC–MSMS. A combined analysis of HBCD and TBBPA is problematic due to the hydroxyl groups in the TBBPA molecule. However, using a specific mesh-size sodium sulphate in ASE extraction and an acid silica column combined with a Sep-pack Plus silica cartridge for purification resulted in recoveries between 80% and 110% for all compounds. The accuracy and reproducibility determined using proficiency test samples were 104% and 4% for the sum of the HBCD isomers. Typical limits of detection were 0.01 ng/g product or 0.004 ng on column, while the linear dynamic range is between 0.01 ng and 10 ng on column. Levels of TBBPA and HBCD isomers were determined in eel samples. TBBPA was occasionally detected and only marginally above the quantification limit of 0.05 ng/g, whereas total amounts of HBCD were between 0.2 and 150 ng/g with a-HBCD being the dominant HBCD isomer.
Soil inoculation method determines the strength of plant-soil interactions
Voorde, T.F.J. van de; Ruijten, M. ; Putten, W.H. van der; Bezemer, T.M. - \ 2012
Soil Biology and Biochemistry 55 (2012). - ISSN 0038-0717 - p. 1 - 6.
vesicular-arbuscular mycorrhizal - senecio-jacobaea - community composition - feedback - biota - microorganisms - rhizosphere - succession - diversity - dynamics
There is increasing evidence that interactions between plants and biotic components of the soil influence plant productivity and plant community composition. Many plant–soil feedback experiments start from inoculating relatively small amounts of natural soil to sterilized bulk soil. These soil inocula may include a variety of size classes of soil biota, each having a different role in the observed soil feedback effects. In order to examine what may be the effect of various size classes of soil biota we compared inoculation with natural field soil sieved through a 1 mm mesh, a soil suspension also sieved through a 1 mm mesh, and a microbial suspension sieved through a 20 µm mesh. We tested these effects for different populations of the same plant species and for different soil origins. Plant biomass was greatest in pots inoculated with the microbial suspension and smallest in pots inoculated with sieved soil, both in the first and second growth phase, and there was no significant population or soil origin effect. Plant-feeding nematodes were almost exclusively found in the sieved soil treatment. We show that processing the soil to obtain a microbial suspension reduces the strength of the soil effect in both the first and second growth phase. We also show that the results obtained with inoculating sieved soil and with a soil suspension are not comparable. In conclusion, when designing plant–soil feedback experiments, it is crucial to consider that soil inoculum preparation can strongly influence the observed soil effect.
The curse of the black box
Cortois, R. ; Deyn, G.B. de - \ 2012
Plant and Soil 350 (2012)1-2. - ISSN 0032-079X - p. 27 - 33.
arbuscular mycorrhizal fungi - plant-soil feedbacks - biodiversity - diversity - agroecosystems - productivity - management - community - maize - biota
Background Soil is a foremost provider of (agro-)ecosystem services, making plant-soil interactions pivotal in agriculture research. The functioning of soils entails complex interactions between soil biota and the abiotic soil environment and is therefore often considered as a ‘black box’. The study of Verbruggen et al. (this volume) tries to crack the black box open by examining the role of soil microbial communities from conventional and organic farming fields for the growth of Zea mays and phosphorous retention in the soil. Scope In this commentary on the paper of Verbruggen et al. (2011) we use the study to illustrate that investigating soils, and specifically the role of soil biota in ecosystem functioning, is not straightforward, given the overwhelming soil biodiversity and the complexity of soil as a habitat. We discuss the key elements that need to be considered in order to translate results of highly controlled experiments with inoculated soil biota to their functioning in the field. Conclusions Verbruggen et al. contribute to our understanding of the functional role of AMF in agro-ecosystems. Yet the results only allow us to merely speculate about the realized functional role of AMF communities in the field, a very interesting avenue for future research.
Driver-pressure-impact and response-recovery chains in European rivers: observed and predicted effects on BQEs
Feld, C.K. ; Dahm, V. ; Lorenz, A. ; Logez, M. ; Marzin, A. ; Verdonschot, P.F.M. ; Michels, H.C.U. ; Keizer-Vlek, H.E. - \ 2011
Brussel : European Commission - 227
stroomgebieden - aquatische ecologie - ecologisch herstel - rivieren - biota - databanken - europa - watersheds - aquatic ecology - ecological restoration - rivers - databases - europe
The report presented in the following is part of the outcome of WISER’s river Workpackage WP5.1 and as such part of the module on aquatic ecosystem management and restoration. The ultimate goal of WP5.1 is to provide guidance on best practice restoration and management to the practitioners in River Basin Management. Therefore, a series of analyses was undertaken, each of which used a part of the WP5.1 database in order to track two major pathways of biological response: 1) the response of riverine biota to environmental pressures (degradation) and 2) the response of biota to the reduction of these impacts (restoration). This report attempts to provide empirical evidence on the environment-biota relationships for both pathways.
Intra- and interspecific plant-soil interactions, soil legacies and priority effects during old-field succession
Voorde, T.F.J. van de; Putten, W.H. van der; Bezemer, T.M. - \ 2011
Journal of Ecology 99 (2011)4. - ISSN 0022-0477 - p. 945 - 953.
senecio-jacobaea l - arbuscular mycorrhizal communities - pyrrolizidine alkaloids - grassland communities - feedback - diversity - ragwort - rhizosphere - ecology - biota
1. Legacy effects of plant influences on abiotic and biotic soil properties can result in priority effects that influence the structure and composition of plant communities. To better understand the role of these plant–soil interactions, here we expand the concept of plant–soil feedbacks from a within-species approach (intraspecific plant–soil feedback) to a between-species approach (interspecific plant–soil interactions). 2. In a greenhouse experiment, we tested how the early successional Jacobaea vulgaris affects its own performance and the performance of 30 co-occurring plant species via changes in abiotic and biotic soil conditions. In addition, we examined the reciprocal effect of the co-occurring species on J. vulgaris. 3. Our study had three important results. First, J. vulgaris exhibits strong negative plant–soil feedback. Secondly, there were large differences among the co-occurring species in interspecific plant–soil effects on J. vulgaris growth. Approximately, half the species reduced J. vulgaris performance, whereas the other half had no effect. Thirdly, soil conditioned by J. vulgaris had a positive or neutral effect on the growth of the co-occurring species. 4. To test the soil effects of entire plant communities, in 10 old-fields that differed in time since abandonment we recorded the identity of all plants surrounding J. vulgaris individuals. We calculated the weighted soil effect of this community on J. vulgaris and the reciprocal effect of J. vulgaris on the community. There was a positive linear relationship between time since abandonment and the weighted feedback effect of J. vulgaris on the plant community. 5. We suggest three mechanisms how the legacy of plant–soil interactions may enhance the rate of succession through priority effects: early successional plant species exert negative plant–soil feedback; co-occurring plant species cause negative interspecific plant–soil effects to the early successional species; and the early successional species have overall positive interspecific plant–soil effects on the co-occurring plant species. 6.Synthesis. The performance of an early successional species can be reduced directly by the legacy effects of intraspecific plant–soil feedback, as well as indirectly by the legacy effects of both intra- and interspecific plant–soil interactions. These intra- and interspecific plant–soil interactions can prioritize transitions of plant species in plant communities
Comparison of quantification methods for the analysis of polychlorinated alkanes using electron capture negative ionisation mass spectrometry
Rusina, T. ; Korytar, P. ; Boer, J. de - \ 2011
International Journal of Environmental Analytical Chemistry 91 (2011)4. - ISSN 0306-7319 - p. 319 - 332.
chain chlorinated paraffins - n-alkanes - environmental-samples - chemical-ionization - group patterns - fish samples - polychloroalkanes - standards - biota
Four quantification methods for short-chain chlorinated paraffins (SCCPs) or polychlorinated alkanes (PCAs) using gas chromatography electron capture negative ionisation low resolution mass spectrometry (GC-ECNI-LRMS) were investigated. The method based on visual comparison of congener group patterns of external standards used for quantification and fish samples was very sensitive for the choice of the quantification standard. Two other methods used the existing relation of the response factors with the chlorine content of SCCP mixtures for quantification. Results from the three methods above deviated from nominal values less than 20%. This was ~50% when individual PCA standards were applied for quantification of SCCPs. The deviation is probably caused by the fact that only C10 carbon chain length standards with 5-9 chlorine atoms could be used. However, quantification using individual PCA standards is a promising method provided more standards will become commercially available. The clear advantage is that the standards are defined, which makes quantification comparable between different laboratories. Application of all four quantification methods to the analysis of four different fish samples gave results that agreed with the median values within ±40%
Plant-soil feedback: Experimental approaches, statistical analyses and biological interpretations
Brinkman, E.P. ; Putten, W.H. van der; Bakker, E.J. ; Verhoeven, K.J.F. - \ 2010
Journal of Ecology 98 (2010)5. - ISSN 0022-0477 - p. 1063 - 1073.
vesicular-arbuscular mycorrhiza - grass ammophila-arenaria - community - diversity - pathogens - growth - succession - nematodes - dynamics - biota
1. Feedback between plants and soil organisms has become widely recognized as a driving force of community composition and ecosystem functioning. However, there is little uniformity in quantification and analysis of plant–soil feedback effects. Meta-analysis suggested that the various experimental methods tend to result in different feedback values. Yet, a direct comparison of the different experimental approaches and their statistical analyses is lacking. 2. We used currently applied methods to calculate plant–soil feedback value ranges and compared their statistical analyses to those based on actual biomass data. Then, we re-analysed a case study to compare plant–soil feedback values obtained under the same environmental conditions, but using different experimental approaches: soil sterilization, addition of soil inoculum, and soil conditioning by ‘own’ vs. ‘foreign’ plant species. 3. Different measures to calculate plant–soil feedback values were more variable in positive than in negative feedback values. Analysis of calculated feedback values that are based on treatment averages can lead to a serious inflation of type I errors. 4. In our case study, both the strength and the direction of the feedback effects depended on the experimental approach that was chosen, leading to diverging conclusions on whether feedback to a certain soil was positive or negative. Soil sterilization and addition of soil organisms yielded larger feedback than comparison of own and foreign soil. 5. Synthesis. The ecological interpretation of plant–soil feedback effects strongly depends on the experimental procedure. When the research question focuses on the strength and the sign of plant–soil feedback, soil sterilization (presumed that the side effect of increased nutrient availability can be controlled) or addition of soil inoculum is to be preferred. When the research question concerns the specificity of soil feedback effects, plant performance can be better compared between own and foreign soil. We recommend that when using calculated feedback values, the original data need to be presented as well in order to trace the cause of the effect.
Plant-soil feedback of native and range expanding plant species is insensitive to temperature
Grunsven, R.H.A. van; Veenendaal, E.M. ; Bezemer, T.M. ; Putten, W.H. van der - \ 2010
Oecologia 162 (2010)4. - ISSN 0029-8549 - p. 1059 - 1069.
climate-change - changing climate - environmental characteristics - population-dynamics - ammophila-arenaria - co2 enrichment - pathogens - community - world - biota
Temperature change affects many aboveground and belowground ecosystem processes. Here we investigate the effect of a 5°C temperature increase on plant–soil feedback. We compare plant species from a temperate climate region with immigrant plants that originate from warmer regions and have recently shifted their range polewards. We tested whether the magnitude of plant–soil feedback is affected by ambient temperature and whether the effect of temperature differs between these groups of plant species. Six European/Eurasian plant species that recently colonized the Netherlands (non-natives), and six related species (natives) from the Netherlands were selected. Plant–soil feedback of these species was determined by comparing performance in conspecific and heterospecific soils. In order to test the effect of temperature on these plant–soil feedback interactions, the experiments were performed at two greenhouse temperatures of 20/15°C and 25/20°C, respectively. Inoculation with unconditioned soil had the same effect on natives and non-natives. However, the effect of conspecific conditioned soil was negative compared to heterospecific soil for natives, but was positive for non-natives. In both cases, plant–soil interactions were not affected by temperature. Therefore, we conclude that the temperature component of climate change does not affect the direction, or strength of plant–soil feedback, neither for native nor for non-native plant species. However, as the non-natives have a more positive soil feedback than natives, climate warming may introduce new plant species in temperate regions that have less soil-borne control of abundance
Plant-soil interactions in the expansion and native range of a poleward shifting plant species
Grunsven, R.H.A. van; Putten, W.H. van der; Bezemer, T.M. ; Berendse, F. ; Veenendaal, E.M. - \ 2010
Global Change Biology 16 (2010)1. - ISSN 1354-1013 - p. 380 - 385.
climate-change - ammophila-arenaria - enemy release - feedback - succession - diversity - pathogens - biota - communities - herbivores
Climate warming causes range shifts of many species toward higher latitudes and altitudes. However, range shifts of host species do not necessarily proceed at the same rates as those of their enemies and symbionts. Here, we examined how a range shifting plant species performs in soil from its original range in comparison with soil from the expansion range. Tragopogon dubius is currently expanding from southern into north-western Europe and we examined how this plant species responds to soil communities from its original and expansion ranges. We compared the performance of T. dubius with that of the closely related Tragopogon pratensis, which has a natural occurrence along the entire latitudinal gradient. Inoculation with the rhizosphere soil from T. dubius populations of the original range had a more negative effect on plant biomass production than inoculation with rhizosphere soil from the expansion range. Interestingly, the nonrange expander T. pratensis experienced a net negative soil effect throughout this entire range. The effects observed in this species pair may be due to release from soil born enemies or accumulation of beneficial soil born organisms. If this phenomenon applies broadly to other species, then range expansion may enable plants species to show enhanced performance
Hoe snel bereiken doelsoorten een nieuw gegraven loop?
Verdonschot, P.F.M. ; Didderen, K. - \ 2009
H2O : tijdschrift voor watervoorziening en afvalwaterbehandeling 42 (2009)9. - ISSN 0166-8439 - p. 29 - 31.
waterbeheer - waterlopen - herstel - ecosystemen - effecten - habitats - biota - monitoring - natuurbeheer - natuurtechniek - aquatische ecologie - ecologisch herstel - natuurontwikkeling - drenthe - water management - streams - rehabilitation - ecosystems - effects - nature management - ecological engineering - aquatic ecology - ecological restoration - nature development
Over de effecten van grootschalige beekherstelprojecten en de mate waarin dergelijke projecten bijdragen aan het behalen van natuur- en KRW-doelen is nog niet veel bekend. Onderzoekers van Alterra volgden de veranderingen in het ecosysteem van de in 2006 gegraven Geeserstroom in Drenthe. De resultaten tonen dat de beekfauna na twee jaar gekenmerkt wordt door kolonisten en dat het aantal echte beeksoorten achterblijft. Dit duidt op dispersieproblemen of het ontbreken van een geschikt leefmilieu voor de verwachte laaglandbeeksoorten
Bioaccumulatie in schelpdieren t.b.v. het Nader Onderzoek Nieuwe Merwede
Hoek-van Nieuwenhuizen, M. van; Kotterman, M.J.J. - \ 2008
IJmuiden : IMARES (Rapport / Wageningen IMARES C056/08) - 22
waterbodems - ecotoxicologie - herstel - biota - kwaliteitsnormen - referentienormen - ecologische risicoschatting - rivierengebied - zuid-holland - water bottoms - ecotoxicology - rehabilitation - quality standards - reference standards - ecological risk assessment
In 2008 is een beperkt Nader Onderzoek uitgevoerd m.b.t. de waterbodem van de Nieuwe Merwede met als doel een beslissing te kunnen ondersteunen of de waterbodem gesaneerd moet worden. Onderdeel van dit onderzoek is het inschatten van de ecologische risico’s aan de hand van bioaccumulatie van stoffen in organismen die in contact staan met de waterbodem, in dit geval Corbicula’s. IMARES is verzocht dit deelonderzoek uit te voeren. Dit rapport beschrijft de gemeten gehalten aan microcontaminanten in Corbicula’s afkomstig van verschillende locaties in de Nieuwe Merwede en de toetsing daarvan aan de op dit moment beschikbare biota-normen die afgeleid zijn voor de Kaderrichtlijn Water.
Plant species and functional group effects on abiotic and microbial soil properties and plant-soil feedback responses in two grasslands
Bezemer, T.M. ; Lawson, C.S. ; Hedlund, K. ; Edwards, A.R. ; Brooks, A.J. ; Igual, J.M. ; Mortimer, S.R. ; Putten, W.H. van der - \ 2006
Journal of Ecology 94 (2006)5. - ISSN 0022-0477 - p. 893 - 904.
fatty-acid analysis - community structure - diversity - rhizosphere - vegetation - biota - dynamics - biomass - succession - management
1 Plant species differ in their capacity to influence soil organic matter, soil nutrient availability and the composition of soil microbial communities. Their influences on soil properties result in net positive or negative feedback effects, which influence plant performance and plant community composition. 2 For two grassland systems, one on a sandy soil in the Netherlands and one on a chalk soil in the United Kingdom, we investigated how individual plant species grown in monocultures changed abiotic and biotic soil conditions. Then, we determined feedback effects of these soils to plants of the same or different species. Feedback effects were analysed at the level of plant species and plant taxonomic groups (grasses vs. forbs). 3 In the sandy soils, plant species differed in their effects on soil chemical properties, in particular potassium levels, but PLFA (phospholipid fatty acid) signatures of the soil microbial community did not differ between plant species. The effects of soil chemical properties were even greater when grasses and forbs were compared, especially because potassium levels were lower in grass monocultures. 4 In the chalk soil, there were no effects of plant species on soil chemical properties, but PLFA profiles differed significantly between soils from different monocultures. PLFA profiles differed between species, rather than between grasses and forbs. 5 In the feedback experiment, all plant species in sandy soils grew less vigorously in soils conditioned by grasses than in soils conditioned by forbs. These effects correlated significantly with soil chemical properties. None of the seven plant species showed significant differences between performance in soil conditioned by the same vs. other plant species. 6 In the chalk soil, Sanguisorba minor and in particular Briza media performed best in soil collected from conspecifics, while Bromus erectus performed best in soil from heterospecifics. There was no distinctive pattern between soils collected from forb and grass monocultures, and plant performance could not be related to soil chemical properties or PLFA signatures. 7 Our study shows that mechanisms of plant-soil feedback can depend on plant species, plant taxonomic (or functional) groups and site-specific differences in abiotic and biotic soil properties. Understanding how plant species can influence their rhizosphere, and how other plant species respond to these changes, will greatly enhance our understanding of the functioning and stability of ecosystems.
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