Publications of Monique Carnol
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See detailStreptomyces from Moonmilk, an Untapped Source of New Bioactive Compounds
Martinet, Loïc ULiege; Maciejewska, Marta; Adam, Delphine ULiege 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 ULiege; 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 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 ULiege; Chartin, Caroline; van Wesemael, Bas et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2017), 21(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 ULiege 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 detailAssessment of the Potential Role of Streptomyces in Cave Moonmilk Formation
Maciejewska, Marta; Adam, Delphine; Naomé, Aymeric ULiege et al

in Frontiers in Microbiology (2017), 8

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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 detailLes sols, richesses cachées de la planète
Garré, Sarah ULiege; Carnol, Monique ULiege; Cornelis, Jean-Thomas ULiege

Speech/Talk (2015)

Toute forme de vie sur terre doit beaucoup aux sols. Aussi discrets que dynamiques, vitaux que complexes, les sols sont des réacteurs bio-physico-chimiques, situés à l’interface entre les roches, la ... [more ▼]

Toute forme de vie sur terre doit beaucoup aux sols. Aussi discrets que dynamiques, vitaux que complexes, les sols sont des réacteurs bio-physico-chimiques, situés à l’interface entre les roches, la végétation, l’air et l’eau. L’étude de cette ressource non renouvelable, soumise à des pressions croissantes, requiert une approche interdisciplinaire, indispensable pour une gestion raisonnée et durable des écosystèmes. Comment sont définis les sols, comment les étudions-nous, comment aborder leur diversité et leurs fonctionnalités ? Quels secrets ont-ils à nous livrer ? La leçon inaugurale abordera la formation des sols, leur diversité ainsi que leurs fonctions écologiques. La variété des organismes au sein des sols et la notion de qualité des sols seront évoquées à travers la triangulation biodiversité – fonctions – services écosystémiques. Des techniques innovantes, permettant d’étudier cette interface extrêmement complexe et diversifiée, seront présentées et le fonctionnement ainsi que l’intérêt des sols seront illustrés par des exemples concrets issus de recherches récentes. [less ▲]

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See detailThe role of tree species diversity in drought resistance of oak and beech sapling
Rahman, Md Masudur ULiege; Verheyen, Kris; Carnol, Monique ULiege

Poster (2015, March 21)

Drier condition during the growing season have been predicted in the future. It has been suggested that diverse forest could maintain productivity and provide better ecosystem services under stress ... [more ▼]

Drier condition during the growing season have been predicted in the future. It has been suggested that diverse forest could maintain productivity and provide better ecosystem services under stress condition such as drought. However, those studies focused mainly on mature forest and little known about young forest. Oak and beech are the important species in European forestry, and may face a strong challenge in the future. Drought effects on young ( ̴5yr) oak and beech saplings in monoculture and mixed with other species are not known. Moreover, single studies evaluating both above- and below-ground ecosystem response to drought are scarce. A two-year manipulative field experiment has been planned to answer the following questions. (i) Can species mixtures improve oak and beech sapling performances under drought conditions? (ii) What are the mechanisms underlying ecosystem functioning and sapling performance in mixed species stands subjected to drought? A 3m × 3m rainout shelter will be placed only in growing season in Zedelgem sites of FORBIO experimental platform (http://www.treedivbelgium.ugent.be/pl_forbio.html). Tree diversity vary from 1 to 4 species and about 50% of precipitation will be taken off. Both aboveground sapling performance and belowground microbial properties and biogeochemical processes will be investigated. We will present the design of the experimental tree species diversity plantation of Zedelgem site, the setting of the drought experiment and planned analysis [less ▲]

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See detailMicrobial biomass increases with tree species diversity in European forest soils
Carnol, Monique ULiege; Baeten, Lander; Bosman, Bernard ULiege et al

Conference (2015)

Increasing tree species diversity in forests might contribute to ecosystem-service maintenance, as well as to the reconciliation of regulating, provisioning and supporting services within the frame of ... [more ▼]

Increasing tree species diversity in forests might contribute to ecosystem-service maintenance, as well as to the reconciliation of regulating, provisioning and supporting services within the frame of multifunctional and sustainable forestry. Individual tree species influence biogeochemical cycling through element deposition (throughfall, litterfall), and through microbial activities in the soil. Yet, the influence of mixing tree species on these ecosystem processes 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 a tree diversity gradient of 1 to 5 tree 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. We analysed the impact of tree species diversity and the role of other controlling factors on the metabolic diversity of soil bacteria (BIOLOG Ecoplate), soil microbial biomass (fumigation-extraction) and potential nitrification (shaken soil slurry) in the forest floor and the upper organo-mineral soil horizon. Mean values of microbial biomass carbon ranged from 3264 (Italy) to 8717 (Finland) mg kg-1 in the forest floor. Statistical models predict microbial biomass to increase in both horizons by 7-8% with each step increase in tree diversity. Increased proportion of conifers was linked to a decrease in the metabolic diversity of soil bacteria. These tree diversity effects could be linked to soil drivers, such as pH, total and labile carbon and nitrogen. [less ▲]

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See detailTree species diversity effects on soil microbial biomass, diversity and activity across European forest types
Carnol, Monique ULiege; Baeten, Lander; Bosman, Bernard ULiege et al

Conference (2014, December)

Increasing tree species diversity in forests might contribute to ecosystem-service maintenance, as well as to the reconciliation of regulating, provisioning and supporting services within the frame of ... [more ▼]

Increasing tree species diversity in forests might contribute to ecosystem-service maintenance, as well as to the reconciliation of regulating, provisioning and supporting services within the frame of multifunctional and sustainable forestry. Individual tree species influence biogeochemical cycling through element deposition (throughfall, litterfall), and through microbial activities in the soil. Yet, the influence of mixing tree species on these ecosystem processes 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 a tree diversity gradient of 1 to 5 tree 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. We analysed the impact of tree species diversity and the role of other controlling factors on the metabolic diversity of soil bacteria (BIOLOG Ecoplate), soil microbial biomass (fumigation-extraction) and potential nitrification (shaken soil slurry) in the forest floor and the upper organo-mineral soil horizon. Mean values of microbial biomass carbon ranged from 240 (Poland) to 1762 (Germany) mg kg-1 in the forest floor and from 4197 (Italy) to 11207 (Finland) mg kg-1 in the upper organo-mineral horizon. Tree diversity and soil water content were important controlling factors. Statistical models predict microbial biomass to increase in both horizons by 7-8% with each step increase in tree diversity. Metabolic diversity of soil bacteria (% of substrates used) showed high variability both within and between sites. Further results analysed with mixed linear models will be presented and discussed. [less ▲]

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See detailEffect of tree species mixture on earthworm communities on a continental scale
De Wandeler, Hans; Baeten, Lander; Carnol, Monique ULiege et al

Poster (2014, December)

The belowground food web represents a major part of associated biodiversity in forest ecosystems, and plays a significant role in the ecosystem processes of litter decomposition and nutrient turnover ... [more ▼]

The belowground food web represents a major part of associated biodiversity in forest ecosystems, and plays a significant role in the ecosystem processes of litter decomposition and nutrient turnover. Past research has demonstrated overwhelming evidence of strong tree species identity effects on earthworm communities. It has been proposed that increased plant community diversity would be beneficial to the abundance and diversity of the belowground food web, but effects of tree species diversity on earthworm communities have seldom been reported, and are inconclusive. In this study at continental scale we evaluated whether tree species diversity positively affects earthworm biomass and diversity. For this purpose the FunDivEUROPE Exploratory Platform was used with 209 plots in 6 regions well spread over Europe with a low within-region site variability, but a within-region tree species diversity gradient from monocultures to 3 or 4 species plots. In every plot earthworms were sampled using a combined method of mustard extraction and hand sorting of litter and a soil monolith. Data are being analysed with multivariate tools and mixed effects models. First results suggest only limited influence of tree diversity on the biomass of earthworm communities at continental scale. Tree diversity effects are weak, context specific and interacting with tree identity. In nutrient poor soils we found a negative tree diversity effect on earthworm biomass when deciduous monocultures are enriched with coniferous species, while in rich soils we found a positive tree diversity effect which could be related with the food security this provides to the earthworm community. [less ▲]

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See detailEffects of long term soil organic matter restitution mode on soil heterotrophic respiration and soil biological properties.
Buysse, Pauline ULiege; Carnol, Monique ULiege; Malchair, Sandrine ULiege et al

Poster (2011, July)

Soil heterotrophic respiration (SHR) is the process by which CO2 is released during organic matter decomposition. It is generally expected that SHR can act as a positive feedback to global warming ... [more ▼]

Soil heterotrophic respiration (SHR) is the process by which CO2 is released during organic matter decomposition. It is generally expected that SHR can act as a positive feedback to global warming, therefore leading to more CO2 release into the atmosphere. It is thus important to better understand this process. Particularly, agricultural soils may behave as important CO2 sources that are strongly influenced by soil and crop management (e.g. organic matter restitution modes, hereafter “OM-RM”). The present study aimed at determining if, after more than 50 years of application of different OM-RM, (1) significant differences of SHR fluxes can be observed between treatments, (2) SHR responses to temperature and soil moisture content can be affected by the OM-RM and (3) the experimental design is suitable to assess potential differences between treatments. The experimental field is situated in Liroux, near Gembloux in Belgium. At that site, a long term experiment with different OM-RM runs from 1959 onwards. For the present study, three contrasted treatments were considered: (1) exportation of all residues after harvest, (2) addition of manure once every three to four years and (3) restitution of residues after harvest. SHR flux measurements were carried out manually on fourteen occasions from 2 April to 30 July 2010, using a dynamic closed chamber system. Temperature and soil moisture content at 5 cm depth were also measured manually. Results showed that after more than 50 years of OM-RM application, no significant differences could be observed between the three treatments in terms of SHR fluxes and SHR responses to temperature or soil moisture, while the soil organic carbon content did vary significantly between them. The sensitivity to temperature was quite low in all treatments, with a mean Q10 value of 1,36. Besides, SHR fluxes were seen to be more responsive to increases in soil water content than to absolute soil moisture content values. Indeed, when soil moisture content increased between two consecutive measurement dates, the ratio of the corresponding SHR fluxes was larger than 1. Particularly dry conditions in 2010 may actually have caused the fluxes to be very low, making the assessment of differences between treatments more difficult. Moreover, soil dryness is likely to be responsible for the SHR flux increases after rain events, as caused by re-solubilization of organic compounds. Also, an important spatial variability was observed, which may have obscured the assessment of potential differences between treatments. Further investigations will consist in performing a new flux measurement campaign in 2011 that will take the spatial variability issue into account, and in monitoring microbial and soil properties in the different treatments, such as microbial biomass, metabolic activity and labile carbon. [less ▲]

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See detailEffects of long term soil organic matter restitution mode on soil heterotrophic respiration and soil biological properties.
Buysse, Pauline ULiege; Carnol, Monique ULiege; Malchair, Sandrine ULiege et al

Conference (2011, May 12)

For more than 50 years, an agricultural site divided in several plots is submitted to different organic matter restitution mode to the soil (crop residues, manure,...). The objectives of this study were ... [more ▼]

For more than 50 years, an agricultural site divided in several plots is submitted to different organic matter restitution mode to the soil (crop residues, manure,...). The objectives of this study were to determine (1) whether these different treatments may cause differences between treatments in terms of soil heterotrophic respiration, that would be of the same order of magnitude than differences in total soil organic carbon, (2) how temperature and soil moisture content affect soil heterotrophic respiration in the different treatments, and (3) how different soil biological properties (microbial biomass, metabolic diversity, labile carbon content) are affected in the different treatments. The results from a first measurement campaign carried out in 2010 are presented, together with the remaining questions at this stage of the study. [less ▲]

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See detailElement fluxes, forest floor characteristics and microbial activities under deciduous tree species after conversion of a Norway spruce (Picea abies (L.) Karst.) stand
Bazgir, Masoud ULiege; Guillaume, Patricia ULiege; Carnol, Monique ULiege

Poster (2011, March)

Forest management is currently confronted with major questions, such as how to adapt plantation forests to a changing world. This questioning is not only essential with regard to forest health and ... [more ▼]

Forest management is currently confronted with major questions, such as how to adapt plantation forests to a changing world. This questioning is not only essential with regard to forest health and productivity, but also within the frame of climate mitigation. As Norway spruce monocultures (Picea abies) have been planted in Europe beyond their assumed natural range, are subjected to forest decline and have negative impacts on ecological conditions, conversion into mixed stands has been suggested. Tree species can influence nutrient inputs, soil microbial activity, soil chemistry and nutrient cycling in forest ecosystems. These tree species effects on biogeochemical cycles may vary according to soil type, site characteristics and land use history. The objective of the present study was to quantify element fluxes in throughfall and seepage water, forest floor exchangeable element pools and nitrogen transformations, 12 years after conversion from Picea abies monocultures to a mixed forest stand. Measurements were performed under young and mature Picea abies, Alnus glutinosa (L.) Gaertn., Quercus robur L. and Sorbus aucuparia L. Thus trees have grown on the same site, sharing identical initial soil conditions and site history, so that potential effects on microbial processes and soil properties can be imputed to tree species. Results showed that conversion had a short term impact on nutrient budgets and nutrient cycling in the upper soil layer; in particular on input fluxes of acidifying cations, soil base saturation, net N mineralization and nitrification. [less ▲]

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See detail20 ans d'études dans 2 bassins versants boisés en Ardenne
Guillaume, Patricia; Bosman, Bernard ULiege; Bazgir, Masoud et al

Diverse speeche and writing (2011)

En Région wallonne, de nombreux sols forestiers se caractérisent par un pH faible et une pauvreté en Ca, P et surtout Mg. Depuis 1991, dans le cadre d’études sur le dépérissement forestier et l’impact de ... [more ▼]

En Région wallonne, de nombreux sols forestiers se caractérisent par un pH faible et une pauvreté en Ca, P et surtout Mg. Depuis 1991, dans le cadre d’études sur le dépérissement forestier et l’impact de mesures de gestion forestière, le laboratoire d’Ecologie Végétale et Microbienne (ULg) étudie l’évolution des concentrations et des flux en éléments minéraux dans les principaux compartiments de deux bassins versants. Ce triptyque résume une partie de ces recherches. [less ▲]

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See detailTree species effects on soil microbial activities in a young stand
Guillaume, Patricia ULiege; Bazgir, Masoud; Carnol, Monique ULiege et al

Poster (2010, October)

Tree species effects on soil characteristics and biogeochemistry are mediated by several factors including microclimatic conditions, ground vegetation cover, quality and quantity of litter and roots ... [more ▼]

Tree species effects on soil characteristics and biogeochemistry are mediated by several factors including microclimatic conditions, ground vegetation cover, quality and quantity of litter and roots exudates, interception of atmospheric particules and aerosols, as well as secondary metabolites from litter. Moreover, the effects depend on the activities and characteristics of the microbial populations. Due to complex interactions, tree species effects on biogeochemical cycles may vary according to soil type, site characterisitcs and history, and climate. However, these questions about tree species effects on biogeochemical cycles are of central interest to forested ecosystems functions, such as soil quality (restoration) and soil water protection. This work is part of a long-term study on concentrations and fluxes in main compartments of 2 forested watersheds (Waroneu and Robinette, east Belgium) in relation with forest management. After 2 spruce generations, the Robinette catchment was partially clear-cut in 1996. Since 1998, this watershed is experiencing an ‘extensive’ afforestartion with a mixture of main and secondary tree species, adapted to specific site conditions. This site, provides the opportunity to study tree species effects on the same soil, with the same history. Morever, tree species have different ecological characteristics: N2 fixing species (Alnus glutinosa), secondary broadleaved species (Betula pendula, Sorbus aucuparia, Salix aurita), main broadleaved sepcies (Quercus robur and Fagus sylvatica) and spruce (Picea abies). Here, we analysed the effects of tree species on soil pH and soil microbial activities in the organic layer in relation to carbon and nitrogen cycles: microbial biomass, basal respiration, labile carbon, nitrogen net mineralisation and potential nitrification. Twelve years after plantation, our results showed differences below the different tree species: (1) a higher microbial biomass and a higher substrate use efficiency and organic matter accessbility for microbial populations below spruce as compared with other tree species; (2) higher pH and microbial biomass below secondary than below main broadleaved species; (3) an enhanced nitrification below alder; (4) a higher leaching of nitrate below broadleaved species than below spruce. These results show a short term impact of forest tree species on microbial activities in upper soil layers. Results are discussed in relation to ecological characteristics of tree species. [less ▲]

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See detailShort-term temperature impacts on soil CO2 fluxes: An incubation experiment with agricultural soil samples.
Buysse, Pauline ULiege; Goffin, Stéphanie ULiege; Carnol, Monique ULiege et al

in Geophysical Research Abstracts (2010, May 06), 12

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See detailLes services écosystémiques dans les forêts mélangés et pures: perception des utilisateurs et connaissances scientifiques
Carnol, Monique ULiege; Verheyen, Kris

in Forêt Wallonne (2010), 106(mai/juin 2010), 49-59

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See detailCarte blanche: Pédagogie universitaire: Moi j'enseigne, mais eux apprennent-ils?
Carnol, Monique ULiege

Article for general public (2010)

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