References of "Carnol, Monique"
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See detailla qualité des sols, un capital
Carnol, Monique ULg; Krüger, Inken ULg; Malchair, Sandrine ULg et al

in Le grand livre de la Forêt 2017 (2017)

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See detailMapping Soil Organic Carbon stocks and estimating uncertainties at the regional scale following a legacy sampling strategy (Southern Belgium, Wallonia)
Chartin, Caroline; Stevens, Antoine; Goidts, Esther et al

in Geoderma Regional (2017), 9

The quantification and the spatialisation of reliable SOC stocks (Mg C ha− 1) and total stock (Tg C) baselines and associated uncertainties are fundamental to detect the gains or losses in SOC, and to ... [more ▼]

The quantification and the spatialisation of reliable SOC stocks (Mg C ha− 1) and total stock (Tg C) baselines and associated uncertainties are fundamental to detect the gains or losses in SOC, and to locate sensitive areas with low SOC levels. Here, we aim to both quantify and spatialize SOC stocks at regional scale (southern Belgium) based on data from one non-design-based or model-based sampling scheme. To this end, we developed a computation procedure based on Digital Soil Mapping techniques and stochastic simulations (Monte-Carlo) allowing the estimation of multiple (here, 10,000) independent spatialized datasets. The computation of the prediction uncertainty accounts for the errors associated to both the estimations of i) SOC stocks and ii) parameters of the spatial model. Based on these 10,000 individuals, median SOC stocks and 90% prediction intervals were computed for each pixel, as well as total SOC stocks and their 90% prediction intervals for selected sub-areas and for the entire study area. Hence, a Generalised Additive Model (GAM) explaining 69.3% of the SOC stock variance was calibrated and then validated (R2 = 0.64). The model overestimated low SOC stock (below 50 Mg C ha− 1) and underestimated high SOC stock (especially those above 100 Mg C kg− 1). A positive gradient of SOC stock occurred from the northwest to the center of Wallonia with a slight decrease on the southernmost part, correlating to the evolution of precipitation and temperature (along with elevation) and dominant land use. At the catchment scale higher SOC stocks were predicted on valley bottoms, especially for poorly drained soils under grassland. Mean predicted SOC stocks for cropland and grassland in Wallonia were of 26.58 Tg C (SD 1.52) and 43.30 Tg C (2.93), respectively. The procedure developed here allowed to predict realistic spatial patterns of SOC stocks all over agricultural lands of southern Belgium and to produce reliable statistics of total SOC stocks for each of the 20 combinations of land use/agricultural regions of Wallonia. This procedure appears useful to produce soil maps as policy tools in conducting sustainable management at regional and national scales, and to compute statistics which comply with specific requirements of reporting activities. [less ▲]

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See detailStreptomyces from Moonmilk, an Untapped Source of New Bioactive Compounds
Martinet, Loïc ULg; Maciejewska, Marta; Adam, Delphine ULg et al

Poster (2017, May 24)

Moonmilk speleothems of limestone caves host a rich microbiome, among which Actinobacteria represent one of the most abundant phyla. Ancient medical texts reported that moonmilk had therapeutical ... [more ▼]

Moonmilk speleothems of limestone caves host a rich microbiome, among which Actinobacteria represent one of the most abundant phyla. Ancient medical texts reported that moonmilk had therapeutical properties, thereby suggesting that its filamentous endemic actinobacterial population might be a source of natural products useful in human treatment. In this work, a screening approach was undertaken in order to isolate cultivable Actinobacteria from moonmilk of the Grotte des Collemboles in Belgium, to evaluate their taxonomic profile, and to assess their potential in biosynthesis of antimicrobials. Phylogenetic analysis revealed that all 78 isolates were exclusively affiliated to the genus Streptomyces and clustered into 31 distinct phylotypes displaying various pigmentation patterns and morphological features. Phylotype representatives were tested for antibacterial and antifungal activities and their genomes were mined for secondary metabolite biosynthetic genes coding for non-ribosomal peptide synthetases (NRPSs), and polyketide synthases (PKS). The moonmilk Streptomyces collection was found to display strong inhibitory activities against a wide range of reference organisms, as 94, 71, and 94% of the isolates inhibited or impaired the growth of Gram-positive, Gram-negative bacteria, and fungi, respectively. Interestingly, 90% of the cave strains induced strong growth suppression against the multi-drug resistant Rasamsonia argillacea, a causative agent of invasive mycosis in cystic fibrosis and chronic granulomatous diseases. We are currently identifying molecules responsible for the observed antimicrobial activities which, next to few known bioactive compounds, also reveals many active compounds with molecular masses that do not correspond to known antibiotic deposited in web biomolecules databases such as KNapSAcK, Pubchem, Chemspider. The challenge is to increase the production yields of these unknown compounds, and purify them to further characterize their structure by NMR. Overall, our work supports the common belief that moonmilk might effectively treat various infectious diseases thanks to the presence of a highly diverse population of prolific antimicrobial producing Streptomyces, and thus may indeed constitute a promising reservoir of potentially novel active natural compounds. [less ▲]

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See detailDoes tree species richness attenuate the effect of experimental irrigation and drought on decomposition rate in young plantation forests?
Rahman, Md Masudur ULg; Verheyen, Kris; Castagneyrol, Bastien et al

Poster (2017, April 27)

Expected changes in precipitation in Europe due to climate change are likely to affect soil organic matter (OM) transformation. In forests, increasing tree species diversity might modulate the effect of ... [more ▼]

Expected changes in precipitation in Europe due to climate change are likely to affect soil organic matter (OM) transformation. In forests, increasing tree species diversity might modulate the effect of changed precipitation. We evaluated the effect of tree species richness on the decomposition and stabilization rate in combination with reduced precipitation (FORBIO, Belgium) and irrigation treatment (ORPHEE, southern France) in young (6-8 yr.) experimental plantations. The species richness were one to four in FORBIO and one to five in ORPHEE. Twenty four rainout shelters of 3 m × 3 m were built around oak and beech trees in FORBIO plantation to impose a reduced precipitation treatment, whereas four of the eight blocks (175 m×100 m) in ORPHEE plantation was subjected to irrigation treatment. These treatments resulted in about 4% less soil moisture in FORBIO and about 7% higher soil moisture in ORPHEE compared to control. Commercially available green and rooibos tea bags were buried in the soil at 5-7 cm depth to measure two decomposition indices, known as ‘tea bag index’ (TBI). These TBI are (i) decomposition rate (k) and (ii) stabilization rate (S). The results showed no species richness effect on TBI indices in both reduced precipitation and irrigation treatment. In FORBIO, reduced precipitation resulted in decreased k and increased S compared to control around the beech trees only. In ORPHEE, both k and S were higher in the irrigation treatment compared to control. Overall, TBI indices were higher in FORBIO than ORPHEE and this might be explained by the sandy soils and poor nutrient content at the ORPHEE site. These results suggest that OM decomposition rate may be slower in drier condition and OM stabilization rate may be slower or faster in drier condition, depending on the site quality. The absence of tree species effects on OM transformation indicates that tree species richness would not be able to modulate the effects of changed precipitation patterns in young plantations. We conclude that in young afforestations, soil moisture has more influence on OM transformation than tree species richness. [less ▲]

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See detailAssessment of the Potential Role of Streptomyces in Cave Moonmilk Formation
Maciejewska, Marta; Adam, Delphine; Naomé, Aymeric ULg et al

in Frontiers in Microbiology (2017), 8

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See detailIntegrating biological indicators in a Soil Monitoring Network (SMN) to improve soil quality diagnosis – a study case in Southern Belgium (Wallonia)
Krüger, Inken ULg; Chartin, Caroline; van Wesemael, Bas et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2017), 31(S1),

Soil organisms and their activities are essential for soil ecosystem functioning and they can thus be used as pertinent indicators of soil quality. Recent efforts have been undertaken to include ... [more ▼]

Soil organisms and their activities are essential for soil ecosystem functioning and they can thus be used as pertinent indicators of soil quality. Recent efforts have been undertaken to include biological indicators of soil quality into regional/national monitoring networks. Objectives. The aim of this study was to provide a first dataset of six biological indicators and two eco-physiological quotients for two landscape units in Wallonia. These spatial units are characterized by homogeneous climate conditions, soil type, land-use and management (here, grasslands in the Ardennes, and croplands in the Loam Region). Method. Respiration potential, microbial biomass carbon and nitrogen, net nitrogen mineralization, metabolic potential of soil bacteria and earthworm abundance were measured at a total of 60 sites in two different landscape units (LSU). Variability within each LSU was studied. Data was synthesized through calculation of a comprehensive score and presentation as radar plots. Results. All selected biological indicators were significantly higher under grassland than under cropland soils, highlighting the biological indicators’ power of discrimination between main land use types. Variability within LSU depended on the biological indicator and was generally higher in grassland than in cropland soils. Each site could unambiguously be assigned to its landscape unit based on its calculated comprehensive score. Radar plots allowed an assessment of the distribution of values within a landscape unit at a glance. Conclusions. The pilot-study defined the first baseline values for agricultural soils in Wallonia and laid the foundation for a monitoring network of biological soil quality. [less ▲]

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See detailSoil organic carbon fractionation for improving agricultural soil quality assessment – a case study in Southern Belgium (Wallonia)
Trigalet, Sylvain; Chartin, Caroline; Krüger, Inken ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2017), 21(S1),

Description of the subject. The paper presents and discusses a method for fractionating bulk soil organic carbon (SOC) in meaningful SOC fractions to better assess SOC status and its related soil ... [more ▼]

Description of the subject. The paper presents and discusses a method for fractionating bulk soil organic carbon (SOC) in meaningful SOC fractions to better assess SOC status and its related soil ecosystem functions. Objectives. The objective is to perform an evaluation of ecosystem functions of soil organic matter at plot scale and compare it to the normal operative range of the local agro-ecological region. Method. By separating carbon associated with clay and fine silt particles (stable carbon with slow turnover rate, < 20 μm) and carbon non-associated with this fraction (labile and intermediate carbon with higher turnover rates, ≥ 20 μm), effects of management can be detected more efficiently at different scales. Conclusions. Soil organic carbon fractions, used as proxies for soil ecosystem functions, can be helpful because they represent SOC functional pools. This paper proposes to apply fractionation on samples taken at plot and regional scale. It is therefore possible to establish a normal operative range for a specific agro-region for comparison with the values in individual plots. This allows drawing a baseline for SOC fractions status in a specific agricultural unit. This approach provides valuable information to study and evaluate the impact of agricultural management in the context of enhancing soil quality and functions. [less ▲]

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See detailIntegrating biological indicators in a monitoring network to improve soil quality diagnosis – a case study in Southern Belgium
Krüger, Inken ULg; Chartin, Caroline; van Wesemael, Bas et al

Conference (2016, July 21)

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See detailStocks de Carbone Organique et des incertitudes
Chartin, Caroline; Krüger, Inken ULg; Carnol, Monique ULg et al

Conference (2016, July 05)

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See detailL’intégration d’indicateurs biologiques dans un réseau de surveillance des sols afin d’améliorer le diagnostic de la qualité du sol – une étude de cas dans le sud de la Belgique (Wallonie)
Krüger, Inken ULg; Chartin, Caroline; van Wesemael, Bas et al

Poster (2016, July 05)

Les organismes du sol et leurs activités sont essentiels pour le fonctionnement de l’écosystème du sol et ils peuvent donc servir comme indicateurs de la qualité du sol. Des efforts ont récemment été ... [more ▼]

Les organismes du sol et leurs activités sont essentiels pour le fonctionnement de l’écosystème du sol et ils peuvent donc servir comme indicateurs de la qualité du sol. Des efforts ont récemment été menés pour intégrer les indicateurs biologiques de la qualité du sol dans les réseaux de surveillance régionaux/nationaux. Le but de cette étude était de déterminer des gammes de valeurs pour six indicateurs biologiques et deux quotients éco-physiologiques pour les sols agricoles. La respiration potentielle, la biomasse microbienne (carbone et azote), la minéralisation nette de l’azote, la diversité métabolique des bactéries du sol, l’abondance des vers de terre, le quotient microbien et le quotient métabolique ont été mesurés dans 60 sites dans des régions agricoles contrastées (différents types de sol et climat) et différentes utilisations de sol (prairies et cultures) sélectionnés d’un réseau de surveillance du carbone organique du sol (CARBOSOL). Les liens entre indicateurs biologiques et paramètres chimiques (le pH du sol, carbone organique total, soluble, labile et stable) sont analysés. Quatre des six indicateurs biologiques sélectionnés (respiration potentielle, biomasse microbienne (carbone et azote) et diversité métabolique des bactéries du sol) sont significativement plus élevés sous prairies que sous cultures. Les gammes de valeurs sont plus larges sous prairies que sous cultures. Les indicateurs biologiques sélectionnés ne sont pas significativement influencés par la région agricole. Les meilleures corrélations avec les paramètres chimiques ont été trouvées pour la respiration potentielle et la biomasse microbienne (carbone et azote). L’étude définit des gammes de valeurs pour les sols agricoles à l’échelle régionale (Wallonie) séparées par utilisation de sol (prairies et cultures) et présente une base solide pour l’établissement d’un réseau de surveillance de la qualité biologique du sol. [less ▲]

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See detailMetal binding to the N-terminal cytoplasmic domain of the PIB ATPase HMA4 is required for metal transport in Arabidopsis.
Laurent, Clémentine ULg; Lekeux, Gilles ULg; Ukuwela, Ashwinie A et al

in Plant Molecular Biology (2016), 90

PIB ATPases are metal cation pumps that transport metals across membranes. These proteins possess N- and C-terminal cytoplasmic extensions that contain Cys- and His-rich high affinity metal binding ... [more ▼]

PIB ATPases are metal cation pumps that transport metals across membranes. These proteins possess N- and C-terminal cytoplasmic extensions that contain Cys- and His-rich high affinity metal binding domains, which may be involved in metal sensing, metal ion selectivity and/or in regulation of the pump activity. The PIB ATPase HMA4 (Heavy Metal ATPase 4) plays a central role in metal homeostasis in Arabidopsis thaliana and has a key function in zinc and cadmium hypertolerance and hyperaccumulation in the extremophile plant species Arabidopsis halleri. <br />Here, we examined the function and structure of the N-terminal cytoplasmic metal-binding domain of HMA4. We mutagenized a conserved CCTSE metal-binding motif in the domain and assessed the impact of the mutations on protein function and localization in planta, on metal-binding properties in vitro and on protein structure by Nuclear Magnetic Resonance spectroscopy. <br />The two Cys residues of the motif are essential for the function, but not for localization, of HMA4 in planta, whereas the Glu residue is important but not essential. These residues also determine zinc coordination and affinity. Zinc binding to the N-terminal domain is thus crucial for HMA4 protein function, whereas it is not required to maintain the protein structure. <br />Altogether, combining in vivo and in vitro approaches in our study provides insights towards the molecular understanding of metal transport and specificity of metal P-type ATPases. [less ▲]

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See detailBiotic homogenization can decrease landscape-scale forest multifunctionality
van der Plas, Fons; Manning, Pete; Soliveres, Santiago et al

in Proceedings of the National Academy of Sciences (2016), 113(13), 3557-62

Many experiments have shown that local biodiversity loss impairs the ability of ecosystems to maintain multiple ecosystem functions at high levels (multifunctionality). In contrast, the role of ... [more ▼]

Many experiments have shown that local biodiversity loss impairs the ability of ecosystems to maintain multiple ecosystem functions at high levels (multifunctionality). In contrast, the role of biodiversity in driving ecosystem multifunctionality at landscape scales remains unresolved. We used a comprehensive pan-European dataset, including 16 ecosystem functions measured in 209 forest plots across six European countries, and performed simulations to investigate how local plot-scale richness of tree species (α-diversity) and their turnover between plots (β-diversity) are related to landscape-scale multifunctionality. After accounting for variation in environmental conditions, we found that relationships between α-diversity and landscape-scale multifunctionality varied from positive to negative depending on the multifunctionality metric used. In contrast, when significant, relationships between β-diversity and landscape-scale multifunctionality were always positive, because a high spatial turnover in species composition was closely related to a high spatial turnover in functions that were supported at high levels. Our findings have major implications for forest management and indicate that biotic homogenization can have previously unrecognized and negative consequences for large-scale ecosystem multifunctionality. [less ▲]

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See detailSoil organic carbon fractionation for improving agricultural soil quality diagnosis in different management practices.
Trigalet, Sylvain; Chartin, Caroline; Krüger, Inken ULg et al

Conference (2016)

Preserving ecosystem functions of soil organic matter (SOM) in soils is a key challenge. The need for an efficient diagnosis of SOM state in agricultural soils is a priority in order to facilitate the ... [more ▼]

Preserving ecosystem functions of soil organic matter (SOM) in soils is a key challenge. The need for an efficient diagnosis of SOM state in agricultural soils is a priority in order to facilitate the detection of changes in soil qualityas a result of changes in management practices. The nature of SOM is complex and cannot readily be monitored due to the heterogeneity of its components. Assessment of the SOM level dynamics, typically characterized as the bulk soil organic carbon (SOC), can be refined by taking into account carbon pools with different turnover rates and stability. Fractionating bulk SOC in meaningful soil organic fractions helps to better diagnose SOC status. By separating carbon associated with clay and fine silt particles (stable carbon with slow turnover rate) and carbon nonassociated with this fraction (labile and intermediate carbon with higher turnover rates), effects of management can be detected more efficiently at different spatial and temporal scales. Until now, most work on SOC fractionation has focused on small spatial scales along management or time gradients. The present case study focuses on SOC fractionation applied in order to refine the interpretation of organic matter turnover and SOC sequestration for regional units in Wallonia with comparable climate, management and, to a certain extent, soil conditions. In each unit, random samples from specific land uses are analyzed in order to assess the Normal Operative Ranges (NOR) of SOC fraction contents for each unit and land use combination. Thus, SOC levels of the different fractions of a specific field in a given unit can be compared to its corresponding NOR. It will help to better diagnose agricultural soil quality in terms of organic carbon compared to a bulk SOC diagnosis. [less ▲]

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See detailEstimating Soil Organic Carbon stocks and uncertainties for the National inventory Report - a study case in Southern Belgium
Chartin, Caroline; Stevens, Antoine; Krüger, Inken ULg et al

Conference (2016)

As many other countries, Belgium complies with Annex I of the United Nations Framework Convention on Climate Change (UNFCCC). Belgium thus reports its annual greenhouse gas emissions in its national ... [more ▼]

As many other countries, Belgium complies with Annex I of the United Nations Framework Convention on Climate Change (UNFCCC). Belgium thus reports its annual greenhouse gas emissions in its national inventory report (NIR), with a distinction between emissions/sequestration in cropland and grassland (EU decision 529/2013). The CO2 fluxes are then based on changes in SOC stocks computed for each of these two types of landuse. These stocks are specified for each of the agricultural regions which correspond to areas with similar agricultural practices (rotations and/or livestock) and yield potentials. For Southern Belgium (Wallonia) consisting of ten agricultural regions, the Soil Monitoring Network (SMN) ‘CARBOSOL’ has been developed this last decade to survey the state of agricultural soils by quantifying SOC stocks and their evolution in a reasonable number of locations complying with the time and funds allocated. Unfortunately, the 592 points of the CARBOSOL network do not allow a representative and a sound estimation of SOC stocks and its uncertainties for the 20 possible combinations of land use/agricultural regions. Moreover, the SMN CARBIOSOL is based on a legacy database following a convenience scheme sampling strategy rather than a statistical scheme defined by design-based or model-based strategies. Here, we aim to both quantify SOC budgets (i.e. How much?) and spatialize SOC stocks (i.e. Where?) at regional scale (Southern Belgium) based on data from the SMN described above. To this end, we developed a computation procedure based on Digital Soil Mapping techniques and stochastic simulations (Monte-Carlo) allowing the estimation of multiple (10,000) independent spatialized datasets. This procedure accounts for the uncertainties associated to estimations of both i) SOC stock at the pixelscale and ii) parameters of the models. Based on these 10,000 individual realizations of the spatial model, mean SOC stocks and confidence intervals can be then computed at the pixel scale, for selected sub-areas (i.e. the 20 landuse/agricultural region combinations) and for the entire study area. [less ▲]

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See detailDrivers of earthworm incidence and abundance across European forests
De Wandeler, Hans; Sousa-Silva, Rita; Ampoorter, Evy et al

in Soil Biology & Biochemistry (2016), 99

Earthworms have a significant influence on the structure, composition and functioning of forest ecosystems, but in spite of their role as ecosystem engineers, little is known on the factors controlling ... [more ▼]

Earthworms have a significant influence on the structure, composition and functioning of forest ecosystems, but in spite of their role as ecosystem engineers, little is known on the factors controlling their distribution across European forests. Optimised sampling techniques, as well as more advanced statistical tools and geographical information systems have facilitated studies at the landscape scale. But these, and even larger-scale studies, are scarce due to data limitations, taxonomic inconsistencies and practical issues in linking existing databases. In this continental-scale field-based study we used boosted regression tree modelling to identify and evaluate the relative importance of environmental factors explaining earthworm incidence (presence/absence) and abundance (density and biomass) in European forests. To parameterise our models earthworms were sampled in six forest landscapes along a latitudinal gradient from the boreal north to the Mediterranean south in spring or autumn of 2012, together with several environmental variables. Earthworms were sampled using a combined method of mustard extraction and hand sorting of litter and a soil monolith, after which they were weighed and identified to functional group (epigeic, endogeic and anecic). We found that litter- and soil-related variables best explained earthworm incidence and biomass in European forests, leaving only a minor role to climaterelated variables. Among the litter related variables, understory vegetation played an important role in explaining earthworm incidence and abundance. The relative importance of explanatory variables differed between models for incidence, density and biomass and between earthworm functional groups. Our results suggested that threshold values for soil C:N ratio, forest floor pH and understory plant biomass and plant nutrient concentrations have to be attained before earthworms can occur. Beyond these threshold values, variables like soil C:N ratio, tree litter C:P ratio and forest floor mass further explain earthworm biomass. Mechanisms behind these observations are discussed in the light of future earthworm distribution modelling at continental scale. [less ▲]

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See detailJack-of-all-trades effects drive biodiversity-ecosystem multifunctionality relationships in European forests.
van der Plas, Fons; Manning, Peter; Allan, Eric et al

in Nature communications (2016), 7

There is considerable evidence that biodiversity promotes multiple ecosystem functions (multifunctionality), thus ensuring the delivery of ecosystem services important for human well-being. However, the ... [more ▼]

There is considerable evidence that biodiversity promotes multiple ecosystem functions (multifunctionality), thus ensuring the delivery of ecosystem services important for human well-being. However, the mechanisms underlying this relationship are poorly understood, especially in natural ecosystems. We develop a novel approach to partition biodiversity effects on multifunctionality into three mechanisms and apply this to European forest data. We show that throughout Europe, tree diversity is positively related with multifunctionality when moderate levels of functioning are required, but negatively when very high function levels are desired. For two well-known mechanisms, 'complementarity' and 'selection', we detect only minor effects on multifunctionality. Instead a third, so far overlooked mechanism, the 'jack-of-all-trades' effect, caused by the averaging of individual species effects on function, drives observed patterns. Simulations demonstrate that jack-of-all-trades effects occur whenever species effects on different functions are not perfectly correlated, meaning they may contribute to diversity-multifunctionality relationships in many of the world's ecosystems. [less ▲]

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See detailCarbon substrate utilization and microbial biomass in European forest soils are related to tree species diversity
Carnol, Monique ULg; Baeten, Lander; Bosman, Bernard ULg et al

Poster (2015, December)

Tree species influence biogeochemical cycling through element deposition (throughfall, litterfall), root decomposition and exudates, and through their influence on the microbial activities in the soil ... [more ▼]

Tree species influence biogeochemical cycling through element deposition (throughfall, litterfall), root decomposition and exudates, and through their influence on the microbial activities in the soil. Yet, the effect of mixing tree species on soil functioning is unclear, in particular concerning the microbial diversity and activity in soils. Here we synthesize results from the Exploratory Platform of the FunDivEUROPE project (http://www.fundiveurope.eu/). This network of 209 comparative plots covering tree diversity levels of 1 to 5 species was established in existing mature forests in 6 European regions. These six focal regions represent a gradient of major European forest types from boreal to Mediterranean forests. The aims of this study were to determine the soil microbial biomass and metabolic diversity of soil bacteria for these 6 European forest regions, presenting each a tree species richness gradient and to analyse the impact of tree species richness and the role of other controlling factors. We analysed the relation between tree species diversity, the proportion of coniferous tree species and soil factors (pH, soil organic carbon, water soluble carbon and nitrogen) and the carbon substrate utilisation pattern of soil bacteria (BIOLOG Ecoplate), soil microbial biomass (fumigation-extraction), hot water carbon and nitrogen in the forest floor and the upper mineral soil horizon (linear mixed models, GLM for multivariate abundance data, discriminant correspondence analysis). Mean values of microbial biomass carbon ranged from 3264 (Italy) to 8717 (Finland) mg kg-1 in the forest floor and from 465 (Italy) to 3748 (Finland) mg kg-1 in the mineral soil. Statistical models predicted microbial biomass to increase in both soil layers by 7-8% with each step increase in tree diversity. Increased proportion of conifers was linked to a decrease in the number of carbon substrates used by soil bacteria. The types of carbon sources used were dependent on region, proportion of conifers, soil pH and water-soluble carbon and nitrogen. [less ▲]

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See detailProjet CARBIOSOL: Vers une cartographie des indicateurs biologiques du sol en Région wallonne
Chartin, Caroline; Krüger, Inken ULg; Carnol, Monique ULg et al

Speech/Talk (2015)

Detailed reference viewed: 27 (2 ULg)