Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    '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.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Current refinement(s):

Records 1 - 20 / 94

  • help
  • print

    Print search results

  • export

    Export search results

  • alert
    We will mail you new results for this query: keywords==succession
Check title to add to marked list
Symmetric assembly and disassembly processes in an ecological network
Tylianakis, Jason M. ; Martínez-García, Laura B. ; Richardson, Sarah J. ; Peltzer, Duane A. ; Dickie, Ian A. - \ 2018
Ecology Letters 21 (2018)6. - ISSN 1461-023X - p. 896 - 904.
Community assembly - ecosystem development - mutualist network - mycorrhizal symbiosis - preferential attachment - retrogression - succession
The processes whereby ecological networks emerge, persist and decay throughout ecosystem development are largely unknown. Here we study networks of plant and arbuscular mycorrhizal fungal (AMF) communities along a 120 000 year soil chronosequence, as they undergo assembly (progression) and then disassembly (retrogression). We found that network assembly and disassembly were symmetrical, self-reinforcing processes that together were capable of generating key attributes of network architecture. Plant and AMF species that had short indirect paths to others in the community (i.e. high centrality), rather than many direct interaction partners (i.e. high degree), were best able to attract new interaction partners and, in the case of AMF species, also to retain existing interactions with plants during retrogression. We then show using simulations that these non-random patterns of attachment and detachment promote nestedness of the network. These results have implications for predicting extinction sequences, identifying focal points for invasions and suggesting trajectories for restoration.
Demographic drivers of functional composition dynamics
Muscarella, Robert ; Lohbeck, Madelon ; Martínez-Ramos, Miguel ; Poorter, Lourens ; Rodríguez-Velázquez, Jorge Enrique ; Breugel, Michiel van; Bongers, Frans - \ 2017
Ecology 98 (2017)11. - ISSN 0012-9658 - p. 2743 - 2750.
community-weighted mean traits - leaf phosphorus - seed size - specific leaf area - succession - tropical forests - wood density

Mechanisms of community assembly and ecosystem function are often analyzed using community-weighted mean trait values (CWMs). We present a novel conceptual framework to quantify the contribution of demographic processes (i.e., growth, recruitment, and mortality) to temporal changes in CWMs. We used this framework to analyze mechanisms of secondary succession in wet tropical forests in Mexico. Seed size increased over time, reflecting a trade-off between colonization by small seeds early in succession, to establishment by large seeds later in succession. Specific leaf area (SLA) and leaf phosphorus content decreased over time, reflecting a trade-off between fast growth early in succession vs. high survival late in succession. On average, CWM shifts were driven mainly (70%) by growth of surviving trees that comprise the bulk of standing biomass, then mortality (25%), and weakly by recruitment (5%). Trait shifts of growing and recruiting trees mirrored the CWM trait shifts, and traits of dying trees did not change during succession, indicating that these traits are important for recruitment and growth, but not for mortality, during the first 30 yr of succession. Identifying the demographic drivers of functional composition change links population dynamics to community change, and enhances insights into mechanisms of succession.

Complementarity and selection effects in early and mid-successional plant communities are differentially affected by plant-soil feedback
Jing, Y. ; Bezemer, T.M. ; Putten, W.H. van der - \ 2015
biodiversity effect - biodiversity-productivity relationship - complementary effect - plant-soil feedback - plant-soil interactions - selection effect - soil biota - succession
1. Many studies that provided evidence for a positive relationship between plant diversity and productivity have proposed that this effect may be explained by complementarity among species in resources utilization, or selection of particularly productive species in high-diversity plant communities. Recent studies have related the higher productivity in diverse plant communities to suppression of pathogenic soil biota. If soil biota plays a role in diversity–productivity relationships, the question remains about how they may influence complementarity and selection effects. 2. Here we examine how complementarity and selection effects may depend on soil biota using a plant–soil feedback approach. We used monocultures and mixtures of early successional plant species, which are known to have mostly negative plant–soil feedback effects, and mid-successional plant species, which generally have neutral plant–soil feedback. 3. We found that plant–soil feedback effects differed between monocultures and mixed plant communities, as well as between early and mid-successional plants. This resulted in a significant interaction effect between diversity and successional stage. In monocultures, plant–soil feedback tended to be negative for early and positive for mid-successional plant species. Interestingly, the community feedback responses of the mixed communities were opposite, being positive for early and negative for mid-successional community. 4. Plant–soil feedback differentially affected complementarity and selection effects of early and mid-successional plant communities: it enhanced complementarity effects of early and decreased selection effects of mid-successional species. 5. Synthesis. Soil biota that drive plant–soil feedback effects can influence the diversity–productivity relationship not only through decreased biomass production in monocultures compared to mixtures, but also through influencing complementarity and selection effects among species in mixed plant communities. Our results reveal that biodiversity–productivity relationships depend on plant–soil feedback interactions, which depend on the successional position of the plant. We propose that including successional position and trait-based analyses of plant–soil feedback in diversity-functioning studies will enhance understanding consequences of biodiversity loss for productivity and other ecosystem processes.
Species-specific plant-soil feedback effects on above-ground plant-insect interactions
Kos, M. ; Tuijl, M.A.B. ; Roo, J. de; Mulder, P.P.J. ; Bezemer, T.M. - \ 2015
Journal of Ecology 103 (2015)4. - ISSN 0022-0477 - p. 904 - 914.
below-ground herbivory - pyrrolizidine alkaloids - senecio-jacobaea - multitrophic interactions - community composition - tyria-jacobaeae - responses - succession - pathogens - nutrients
1.Plant–soil feedback (PSF) effects on plant performance strongly depend on the plant species that conditioned the soil. Recent studies have shown that PSF can change above-ground plant–insect interactions via soil-mediated changes in plant quality, but whether these effects depend on species-specific soil conditioning is unknown. We examined how PSF effects of several plant species influence above-ground plant–aphid interactions. 2.We grew ragwort (Jacobaea vulgaris) in field soil conditioned specifically by 10 plant species, belonging to three functional groups (grasses, forbs and legumes), in a multispecies mixture of the conditioned soils and in control (unconditioned) field soil. We measured plant biomass, concentrations of primary (amino acids) and secondary (pyrrolizidine alkaloids) metabolites in phloem exudates, and performance of the generalist aphid Brachycaudus cardui and the specialist Aphis jacobaeae. 3.We observed that plant species, via species-specific effects on soil fungal communities, exerted unique plant–soil effects on J. vulgaris biomass, amino acid concentrations in phloem exudates and aphid performance. The direction and magnitude of the species-specific PSF effects on aphid performance differed between both aphid species. PSF effects on soil fungal communities, plant biomass and A. jacobaeae performance also differed between grasses, forbs and legumes, with soil conditioning by forbs resulting in lowest plant biomass and aphid performance. 4.Synthesis. Our study provides novel evidence that PSF effects on above-ground plant–insect interactions are highly species specific. Our results add a new dimension to the rapidly developing research fields of PSF and above-below-ground interactions, and highlights that these fields are tightly linked.
Root responses of grassland species to spatial heterogeneity of plant–soil feedback
Hendriks, M. ; Visser, E.J.W. ; Visschers, I.S.G. ; Aarts, B.H.J. ; Caluwe, H. de; Smit-Tiekstra, A.E. ; Putten, W.H. van der; Kroon, H. de; Mommer, L. - \ 2015
Functional Ecology 29 (2015)2. - ISSN 0269-8463 - p. 177 - 186.
nutrient heterogeneity - temporal variation - individual plants - community - growth - plasticity - diversity - availability - succession - microbes
Plant roots selectively forage for soil nutrients when these are heterogeneously distributed. In turn, effects of plant roots on biotic and abiotic conditions in the soil, which result in so-called plant–soil feedback can be heterogeneously distributed as well, but it is unknown how this heterogeneity affects root distribution, nutrient uptake and plant biomass production. Here, we investigate plant root distribution patterns as influenced by spatial heterogeneity of plant–soil feedback in soil and quantify consequences for plant nitrogen uptake and biomass production. We conditioned soils by four grassland plant species to obtain ‘own’ and ‘foreign’ soils that differed in biotic conditions similar as is done by the first phase of plant–soil feedback experiments. We used these conditioned soils to create heterogeneous (one patch of own and three patches of foreign soils) or homogeneous substrates where own and foreign soils were mixed. We also included sterilized soil to study the effect of excluding soil biota, such as pathogens, symbionts and decomposers. We supplied 15N as tracer to measure nutrient uptake. In nonsterile conditions, most plant species produced more biomass in heterogeneous than in homogeneous soil. Root biomass and 15N uptake rates were higher in foreign than own soil patches. These differences between heterogeneous and homogeneous soil disappeared when soil was sterilized, suggesting that the effects in nonsterilized soils were due to species-specific soil biota that had responded to soil conditioning. We conclude that plants produce more biomass when own and foreign soils are patchily distributed than when mixed. We show that this enhanced productivity is due to nutrient uptake being overall most efficient when own and foreign soils are spatially separated. We propose that spatial heterogeneity of negative plant–soil feedback in species diverse plant communities may provide a better explanation of overyielding than assuming that plant–soil feedback effects are diluted.
Bedrijfsovername : checklist bedrijfsopvolging en -overdracht
Turenhout, M.N.J. ; Taal, C. ; Haan, H. de - \ 2014
Wageningen : LEI Wageningen UR (LEI 14-092) - 19
visserij - vissersschepen - vissers - bedrijfsopvolging - taxatie - financieren - controlelijsten - fisheries - fishing vessels - fishermen - succession - valuation - financing - checklists
Deze publicatie voorziet in een checklijstlijst voor bedrijfsopvolging en –overdracht ten aanzien van de Nederlandse kottersector. Aandacht wordt geschonken aan: algemene vragen, waardebepaling, financiering en fiscale aspecten. Toegevoegd zijn relevante literatuur en websites.
Unravelling reward value: the effect of host value on memory retention in Nasonia parasitic wasps
Hoedjes, K.M. ; Kralemann, L.E.M. ; Vugt, J.J.F.A. van; Vet, L.E.M. ; Smid, H.M. - \ 2014
Animal Behaviour 96 (2014). - ISSN 0003-3472 - p. 1 - 7.
long-term-memory - sex-ratio - natural variation - pieris-rapae - drosophila - quality - vitripennis - succession - preference - behavior
Learning can be instrumental in acquiring new skills or optimizing behaviour, but it is also costly in terms of energy and when maladaptive associations are formed: the balance between costs and benefits affects memory dynamics. Numerous studies have demonstrated that memory dynamics of animal species depend on the value of the reward during conditioning, even when animals are inexperienced with this reward. How an animal perceives reward value depends on a number of aspects, including the quantity or quality of the reward in terms of energy or fitness for the animal, the internal state of the animal and previous experience. The reliability of the learned association is another aspect, which can be assessed through the frequency of experiences, or through perception of inherent properties of the reward. The reward in oviposition learning of parasitic wasps is a host to parasitize. Different host species can differ in their reward value. This study focused on a specific aspect of reward value, namely host value, i.e. the number and size of emerging offspring, and tested the effect on oviposition learning in parasitic wasps of the genus Nasonia. We conditioned parasitic wasps of the species Nasonia vitripennis and Nasonia giraulti using three different host species as a reward, which differed greatly in their value as a host. However, for both parasitic wasp species, the resulting memory formation was independent of the value of the host. We discuss factors that may be responsible for this observation.
Disturbance–diversity relationships for soil fauna are explained by faunal community biomass in a salt marsh
Thakur, M.P. ; Berg, M.P. ; Eisenhauer, N. ; Langevelde, F. van - \ 2014
Soil Biology and Biochemistry 78 (2014). - ISSN 0038-0717 - p. 30 - 37.
species-diversity - intermediate disturbance - richness - productivity - coexistence - succession - patterns - competition - collembola - dynamics
Disturbance–diversity relationships have long been studied in ecology with a unimodal relationship as the key prediction. Although this relationship has been widely contested, it is rarely tested for soil invertebrate fauna, an important component of terrestrial biodiversity. We tested disturbance–diversity relationships for soil meso- and macrofauna in a salt marsh where periodic sea water inundation and cattle grazing occur as stressors. We hypothesized a unimodal inundation frequency–diversity relationship, whereas we expected grazing to overrule the effects of inundation frequency due to its large effects on the habitat of soil fauna. We found a negative relationship between inundation frequency and diversity at the ungrazed sites and no relationship at the grazed sites. Moreover, we found a negative relationship between community biomass and diversity for soil fauna that may have caused this negative disturbance–diversity relationship. Community biomass at the intermediate inundation frequency increased due to the dominance of Orchestia gammarellus (a macro-detritivore species), which could exploit low quality litters at the ungrazed sites. We highlight that the negative relationship between faunal community biomass and faunal diversity may influence disturbance–diversity relationships and illustrate that total biomass distribution of feeding guilds of soil fauna can improve our understanding of the soil fauna response to stressors in salt marshes.
Salt-marsh erosion and restoration in relation to flood protection on the Wadden Sea barrier island Terschelling
Loon-Steensma, J.M. van; Slim, P.A. ; Decuyper, M. ; Hu, Zhan - \ 2014
Journal of Coastal Conservation 18 (2014)4. - ISSN 1400-0350 - p. 415 - 430.
north norfolk - vegetation - succession - herbivory - estuary - defense - field
This paper explores the impact of erosion and restoration measures on habitat development and on wave damping by a small salt marsh nestled alongside a dike on the Wadden island of Terschelling. The aim is to advance knowledge about the benefits and possible side-effects of salt-marsh restoration. Analysis of a time series of aerial photographs from 1944 to 2010 indicates that the salt marsh decreased steadily in size after maintenance of accretion works was terminated. In the western part of the marsh, which is accessible to sheep, vegetation is low (5–15 cm) and dominated by Salicornia europaea and by Spartina anglica. In the most intensively grazed parts, vegetation is very scarce. The eastern, inaccessible part of the salt marsh is covered by dense patches of the shrubby perennial Atriplex portulacoides and Spartina anglica (15–25 cm in height). SWAN wave models show that wave height at this location is significantly affected by the areal extent of the salt marsh as well as by the vegetation. High or dense vegetation are in the models nearly as effective in damping waves (with an initial height of 0.15 and 0.5 m) as widening the salt-marsh area by 350 m. A low density of low plants, as observed in the grazed part of the marsh, has almost no wave-damping effect. Even under conditions of sea level rise, a broader salt marsh vegetated with high plants significantly affects modelled wave height. Therefore, salt-marsh restoration is an adaptation measure worth exploring, though an array of effect types must be considered.
Zonnehoeve draagt over met nieuwe rechtsvormen : wordt vervolgd : bedrijfscontinuïteit in de biologische landbouw : deel 34
Alebeek, F.A.N. van; Stokkers, R. ; Boxtel, M. van - \ 2014
Ekoland 34 (2014)4. - ISSN 0926-9142 - p. 26 - 27.
multifunctionele landbouw - biologische landbouw - biologisch-dynamische landbouw - agrarische bedrijfsvoering - ondernemerschap - agrarisch eigendomsrecht - vennootschappen - bedrijfsopvolging - multifunctional agriculture - organic farming - biodynamic farming - farm management - entrepreneurship - farmers' rights - partnerships - succession
Complexe multifunctionele bedrijven: hoe draag je die in z’n geheel over? In het vorige nummer de theorie, nu de praktijk. Zonnehoeve in Zeewolde wordt overgedragen aan meerdere ondernemers, en werkt daarbij met in de landbouw ongebruikelijke rechtsvormen.
Dendrochronology of Atriplex portulacoides and Artemisia maritima in Wadden Sea salt marshes
Decuyper, M. ; Slim, P.A. ; Loon-Steensma, J.M. van - \ 2014
Journal of Coastal Conservation 18 (2014)3. - ISSN 1400-0350 - p. 279 - 284.
wood anatomy - chenopodiaceae - competition - succession - herbivory - defense
The study uses a rather unusual method, dendrochronology, to investigate the growth and survival of Atriplex portulacoides L. and Artemisia maritima L. on salt marshes at two field sites on the Dutch North Sea barrier islands of Terschelling and Ameland. By providing information on longevity of these typical salt-marsh shrubs, dendrochronology offers an indirect way to investigate the influence of management regime – grazing in this case – on marsh quality and areal extent. Diminishment of salt marshes is a continuing concern in the northern Netherlands. The two shrub species studied here, A. portulacoides and A. maritima, are common to salt marshes. With their extensive roots and branches, they facilitate sedimentation and stabilize salt marshes. Using dendrochronology, this study found that annual growth rings could be identified to determine shrub age and growth. In A. portulacoides these rings took the form of a narrow band of terminal parenchyma. In A. maritima they were made up of unlignified marginal parenchyma together with higher vessel density at the beginning of the growing season. Growth rings indicated that intense grazing was clearly detrimental to the survival of A. portulacoides at the Terschelling site. However, grazing facilitated survival of A. maritima at the Ameland site by reducing light and nutrient competition from grasses. No growth trends could be found, however, as the lifespan for both species is short and many other influences on shrub growth could be identified.
Independent variations of plant and soil mixtures reveal soil feedback effects on plant community overyielding
Hendriks, M. ; Mommer, L. ; Caluwe, H. de; Smit-Tiekstra, A.E. ; Putten, W.H. van der; Kroon, H. de - \ 2013
Journal of Ecology 101 (2013)2. - ISSN 0022-0477 - p. 287 - 297.
diversity-productivity relationships - grassland experiment - species coexistence - biodiversity - rhizosphere - competition - mechanisms - succession - dynamics
1. Recent studies have shown that the positive relationship between plant diversity and plant biomass ('overyielding') can be explained by soil pathogens depressing productivity more in low than in high diverse plant communities. However, tests of such soil effects in field studies were constrained by experimental limitations to manipulate soil community composition independent of plant community composition. Here, we report of an experiment where feedback effects to plants were tested for both plant and soil monocultures and mixtures. 2. Our results demonstrate that overyielding is the result of plant species in mixture being more growth-limited by 'own' soil biota than by soil biota of other plant species. This effect disappeared when the soils had been sterilized by gamma-irradiation. Mixing plants themselves did not result in overyielding except when grown in the soil of one of the species (Leucanthemum vulgare), where growth of one species disproportionally increased in mixture compared to monoculture. 3. Soil nutrient availability could not explain differences in growth between the non-sterilized soils. Therefore, our results suggest that plant species-specific soil biota rather than the plants have contributed to the plant community overyielding. 4. Species biomass ranking in mixtures highly differed between non-sterilized soils of different histories of soil conditioning, whilst the ranking was more consistent in sterilized soil. Sterilized soils of different origin differed significantly in nutrient availability. These results suggest that shifts in competitive hierarchies depend on plant species-specific interactions influenced by soil biota and cannot be induced by mineral nitrogen. 5. Synthesis. Our results show that overyielding in four plant species mixtures can be due to species-specific interactions between plants and their specific soil biota. Neither mixing the plant species alone nor the differential responses of species to mineral nitrogen influenced community productivity, but mixing soil biota did.
Tropical secondary forest management influences frugivorous bat composition, abundance and fruit consumption in Chiapas, Mexico
Vleut, I. ; Levy-Tacher, S.I. ; Boer, W.F. de; Galindo-Gonzalez, J. - \ 2013
PLoS One 8 (2013)10. - ISSN 1932-6203
rain-forest - community structure - neotropical forest - foraging habitat - scattered trees - seed dispersal - eating bats - succession - vegetation - diversity
Most studies on frugivorous bat assemblages in secondary forests have concentrated on differences among successional stages, and have disregarded the effect of forest management. Secondary forest management practices alter the vegetation structure and fruit availability, important factors associated with differences in frugivorous bat assemblage structure, and fruit consumption and can therefore modify forest succession. Our objective was to elucidate factors (forest structural variables and fruit availability) determining bat diversity, abundance, composition and species-specific abundance of bats in (i) secondary forests managed by Lacandon farmers dominated by Ochroma pyramidale, in (ii) secondary forests without management, and in (iii) mature rain forests in Chiapas, Southern Mexico. Frugivorous bat species diversity (Shannon H’) was similar between forest types. However, bat abundance was highest in rain forest and O. pyramidale forests. Bat species composition was different among forest types with more Carollia sowelli and Sturnira lilium captures in O. pyramidale forests. Overall, bat fruit consumption was dominated by early-successional shrubs, highest late-successional fruit consumption was found in rain forests and more bats consumed early-successional shrub fruits in O. pyramidale forests. Ochroma pyramidale forests presented a higher canopy openness, tree height, lower tree density and diversity of fruit than secondary forests. Tree density and canopy openness were negatively correlated with bat species diversity and bat abundance, but bat abundance increased with fruit abundance and tree height. Hence, secondary forest management alters forests’ structural characteristics and resource availability, and shapes the frugivorous bat community structure, and thereby the fruit consumption by bats
Biotic plant-soil feedbacks across temporal scales
Kardol, P. ; Deyn, G.B. de; Laliberté, E. ; Mariotte, P. ; Hawkes, C.V. - \ 2013
Journal of Ecology 101 (2013)2. - ISSN 0022-0477 - p. 309 - 315.
temperate tree - succession - community - responses - facilitation - strategies - grassland - diversity - pathogens - dynamics
1. Plant effects on soil biota can result in feedbacks affecting plant performance, with consequences for plant community and ecosystem dynamics on short and long time-scales. In addition, the strength and direction of plant-soil feedbacks depend on temporal shifts in abiotic environmental conditions. 2. We synthesize current knowledge on temporal aspects of plant-soil feedbacks and present new ideas to better understand and predict the effects of plant-soil feedbacks on community and ecosystem properties across temporal scales. 3. Explaining short-term temporal feedback dynamics requires us to better understand mechanistic linkages between plants, soil organisms and locally available resources. On the other hand, we need to refine our understanding of the context-dependency of plant-soil feedbacks, as the strength and direction of feedback interactions are influenced by 'external' temporal ecosystem dynamics, such as variation in soil resource availability after disturbance or during succession. 4. Synthesis. Based on our synthesis of temporal aspects of plant-soil feedbacks, we suggest three main avenues for future research: (i) how plant-soil feedbacks changes with ontogeny, (ii) how plant and soil organism traits drive temporal variation in plant-soil feedbacks and (iii) how environmental changes across temporal scales alter the strength and direction of plant-soil feedbacks.
Intestinal Microbiota of Infants With Colic: Development and Specific Signatures
Weerth, C. de; Fuentes Enriquez de Salamanca, S. ; Puylaert, P.G.B. ; Vos, W.M. de - \ 2013
Pediatrics 131 (2013)2. - ISSN 0031-4005 - p. e550 - e558.
gastrointestinal-tract microbiota - human gut microbiome - phylogenetic microarray - bacterial - microflora - succession - diversity - life - age
OBJECTIVES:To provide a comprehensive analysis of the fecal microbiota in infants with colic, as compared with control infants, during their first 100 days of life.METHODS:Microbial DNA of >200 samples from 12 infants with colic and 12 age-matched control infants was extracted and hybridized to a phylogenetic microarray.RESULTS:Microbiota diversity gradually increased after birth only in the control group; moreover, in the first weeks, the diversity of the colic group was significantly lower than that of the control group. The stability of the successive samples also appeared to be significantly lower in the infants with colic for the first weeks. Further analyses revealed which bacterial groups were responsible for colic-related differences in microbiota at age 1 or 2 weeks, the earliest ages with significant differences. Proteobacteria were significantly increased in infants with colic compared with control infants, with a relative abundance that was more than twofold. In contrast, bifidobacteria and lactobacilli were significantly reduced in infants with colic. Moreover, the colic phenotype correlated positively with specific groups of proteobacteria, including bacteria related to Escherichia, Klebsiella, Serratia, Vibrio, Yersinia, and Pseudomonas, but negatively with bacteria belonging to the Bacteroidetes and Firmicutes phyla, the latter of which includes some lactobacilli and canonical groups known to produce butyrate and lactate.CONCLUSIONS:The results indicate the presence of microbial signatures in the first weeks of life in infants who later develop colic. These microbial signatures may be used to understand the excessive crying. The results offer opportunities for early diagnostics as well as for developing specific therapies
Potential vegetation markers – analytical pyrolysis of modern plant species representative of Neolithic SE Spain
Schellekens, J. ; Barbera, G.G. ; Buurman, P. - \ 2013
Journal of Archaeological Science 40 (2013)1. - ISSN 0305-4403 - p. 365 - 379.
soil organic-matter - chemosystematic markers - gc/ms - pine - triterpenes - diterpenes - succession - chemistry - conifers - climate
A selection of plant species that may have been relevant for the Neolithic in the SW Mediterranean have been characterised with pyrolysis gas chromatography mass spectrometry (pyrolysis–GC/MS) in search for molecular vegetation markers. Roots and aerial parts were analysed separately for the following species: Anthyllis cytisoides, Asphodelus cerasiferus, Brachypodium retusum, Cistus albidus, Cistus clusii, Dorycnium pentaphyllum, Ephedra fragilis, Juniperus oxycedrus, Juniperus phoenicea, Olea europaea, Phillyrea angustifolia, Pinus halepensis, Pistacia lentiscus, Quercus coccifera, Rhamnus lycioides, Rosmarinus officinalis, Smilax aspera and Stipa tenacissima; furthermore domesticated plants were analysed, including wheat (Triticum aestivum, Triticum dicoccum, Triticum monococcum, Triticum timopheevi and Triticum turgidum), barley (Hordeum vulgare and H. vulgare Hulled) and legumes (Lathyrus cicera, Lathyrus sativus, Lens culinaris, Pisum sativa, Vicia ervilia, Vicia faba and Vicia sativa). This resulted in 290 potential markers. In addition, the organic matter of surface soils under different vegetation cover has been analysed to test the presence of the potential markers in the soil. Forty-six of the potential markers were detected in the soil organic matter, of which part have not been reported before. The results may be useful for interpretation of the organic matter composition of soils and plant remains, which can be valuable in archaeology.
Matgrass sward plant species benefit from soil organisms
Brinkman, E.P. ; Raaijmakers, C.E. ; Bakx-Schotman, J.M.T. ; Hannula, S.E. ; Kemmers, R.H. ; Boer, W. de; Putten, W.H. van der - \ 2012
Applied Soil Ecology 62 (2012). - ISSN 0929-1393 - p. 61 - 70.
restoration ecology - mycorrhizal fungi - borne fungi - fatty-acids - food-web - grassland - diversity - communities - succession - nematodes
Soil organisms are important in the structuring of plant communities. However, little is known about how to apply this knowledge to vegetation management. Here, we examined if soil organisms may promote plant species of characteristic habitats, and suppress plant species of disturbed habitats. We classified nineteen fields into four types: characteristic and disturbed matgrass swards and successfully and unsuccessfully restored fields. We recorded the vegetation composition and measured biotic and abiotic soil characteristics of the sites. In a pot experiment, we mixed non-sterilized (with soil organisms) or sterilized (without soil organisms) soil inoculum from each field with a common sterilized background soil. We planted seedlings of characteristic matgrass species Antennaria dioica and Nardus stricta, of disturbance indicators Deschampsia flexuosa and Agrostis capillaris, or a combination of the four species. At harvest, we measured root and shoot dry mass of all plants. The vegetation composition of characteristic matgrass swards differed from the disturbed and unsuccessfully restored fields. The successfully restored fields were intermediate. The composition of the nematode community tended to follow the same pattern. In the pot experiment, addition of soil organisms increased the biomass of A. dioica, N. stricta and D. flexuosa, but decreased the biomass of A. capillaris. However, the effect of soil organisms on plant biomass was not related to field type. A. dioica showed a large variation in biomass in non-sterilized, but not in sterilized soil. Soil organisms from some sites increased plant biomass, whereas soil organisms from other sites did not. The biomass of characteristic matgrass plants was lower in the presence of plants from disturbed swards, irrespective of the presence of soil organisms. Probably A. capillaris was so much larger than the other species, that this overruled effects of added soil organisms. Soil organisms promoted growth of plant species characteristic of matgrass swards, whereas they reduced growth of a plant species characteristic of disturbed fields. Soil organisms did not change the outcome of plant interactions, which was won by a disturbance indicator. Nevertheless, measurement of the growth stimulating capacity of a soil may be used to assess opportunities for reintroduction of characteristic plant species.
The importance of plant-soil interactions and plant life history traits for the population dynamics of Jacobaea vulgaris during old-field succession
Voorde, T.F.J. van de; Putten, W.H. van der; Bezemer, T.M. - \ 2012
Oikos 121 (2012)8. - ISSN 0030-1299 - p. 1251 - 1262.
ragwort senecio-jacobaea - grassland biodiversity - fertilizer application - community structure - species composition - individual plants - mown grassland - succession - feedback - ecology
We examined to what extent temporal dynamics of Jacobaea vulgaris cover in old-fields were related to plant–soil feedback, soil nutrients, seed availability and performance, and seedling establishment. Long-term measurements at an experimental field and in ten old-fields representing a chronosequence following land abandonment revealed a remarkably similar hump-shaped temporal pattern of J. vulgaris cover, which peaked at about five years after abandonment. In a plant–soil feedback study, J. vulgaris biomass of plants grown in soil from all chronosequence fields was lower than in sterilized control soil. However, biomass of J. vulgaris in the feedback study was lower when grown in soil collected from fields with a high density of J. vulgaris plants than in soil from fields with a low density of J. vulgaris. When plants were grown again in the conditioned soil, a strong negative plant–soil feedback response was observed for soils from all fields. These results indicate that soils from all stages of the chronosequence can develop a strong negative soil feedback to J. vulgaris, and that there is a positive relationship between J. vulgaris density and the subsequent level of control by the soil community. In a common-garden experiment with turfs collected from the chronosequence fields in which J. vulgaris was seeded, seedling establishment was significantly lower in turfs from older than from young fields. In a seed bank study the number of emerging seedlings declined with time since abandonment of the field. In conclusion, negative plant–soil feedback is an important factor explaining the hump-shaped population development of J. vulgaris. However, it is not operating alone, as propagule availability and characteristics, and competition may also be important. Thus, in order to explain its contribution to plant population dynamics, the role of biotic plant–soil interactions, soil nutrients and life history characteristics along successional gradients should be considered from a community perspective.
Can the negative plant-soil feedback of Jacobaea vulgaris be explained by autotoxicity?
Voorde, T.F.J. van de; Putten, W.H. van der; Bezemer, T.M. - \ 2012
Basic and Applied Ecology 13 (2012)6. - ISSN 1439-1791 - p. 533 - 541.
senecio-jacobaea - pyrrolizidine alkaloids - seed-germination - invasive plants - phenolic-acids - allelopathy - growth - succession - field - grassland
Field and bioassay studies with Jacobaeavulgaris (ragwort) have shown that plants grow poorly in soil originating from the rhizosphere of this species and that this can influence the dynamics of ragwort populations during secondary succession. In the present study we examined whether the negative effect of ragwort on conspecifics may be due to autotoxicity. First, we experimentally established that ragwort exerts negativeplant–soilfeedback. We subsequently examined the inhibitory effects on germination and seedling performance of different strengths of aqueous extracts made from shoot and root tissues of ragwort, and from soil in which ragwort had been growing. The effects of the extracts were tested for seedlings growing in sterilised soil or in glass beads with water. Finally, the inhibitory effect of entire root fragments on seedling performance was tested. We observed that performance of seedlings growing in glass beads was significantly reduced by the high and medium strength root and shoot extracts. Extracts made from soil did not differ significantly from the control, and seedlings growing in sterilised soil were also not affected by ragwort extracts. Seed germination was significantly reduced by the high strength shoot extract only. The root length of seedlings growing in water with root fragments was reduced significantly. We conclude that under laboratory conditions ragwort can be autotoxic and discuss the role that autotoxicity may play in influencing the dynamics of ragwort populations during secondary succession.
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.
Check title to add to marked list
<< previous | next >>

Show 20 50 100 records per page

Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.