References of "Carnol, Monique"
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See detailMicroorganisms in Karsts: a case study in St Anne cave, Belgium
Carnol, Monique ULg; Willems, Luc ULg; Malchair, Sandrine ULg

Poster (2011, September 30)

Despite the importance of microorganisms as geochemical agents over geological times, their extended metabolic diversity and their essential role in element cycles (i.e. mineral dissolution, precipitation ... [more ▼]

Despite the importance of microorganisms as geochemical agents over geological times, their extended metabolic diversity and their essential role in element cycles (i.e. mineral dissolution, precipitation, oxido-reduction processes), microbial community composition and processes as well as their ecological role in karst environments are poorly known. While little was published on cave-dwelling microorganisms until the early 1990s, it is now recognized that microorganisms may mediate many important mineral transformations, originally considered to be inorganic in nature. Indeed, recent evidence (Northup & Lavoie, 2001) proved the implication of microorganisms in karstification through precipitation and dissolution processes, resulting in the deposition of carbonate speleothems, silicates, iron or manganese oxides, sulphur compounds and nitrates and in the breakdown of limestone walls. In this poster, we review some potential processes and signs of microbial activity in caves. We present results of a study on the microbial diversity in the ‘St Anne’ cave, Belgium. We focused on ammonia-oxidizing bacteria (AOB), which are responsible for the first, acidifying step of the nitrification process. Chemical composition of the water, numbers of cultivable bacteria (free and particle-associated bacteria) and the diversity of AOB were studied in waters and sediments of the ‘Chawresse’ (underground river in St Anne), on the cave wall and in the soil aboveground. The use of molecular techniques, based on direct ADN extractions, provide more detailed information on the microbial diversity of an environment, as culture-based techniques retrieve only about 1% of bacterial species present in the environment. Bacterial counts showed that most cultivable bacteria were associated with suspended particles and that their numbers decreased underground. Molecular analyses revealed the presence of AOB in the karst system. Comparison of aboveground and belowground diversity also indicated the possibility of a specific endokarst AOB community. Further research perspectives will be discussed. <br /> <br /> <br />Northup, D.E. and Lavoie, K.H. 2001. Geomicrobiology of caves: A review. Geomicrobiology Journal, 18(3):199-220. [less ▲]

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See detailMicrobiological and chemical characterisation of St Anne cave, Belgium
Carnol, Monique ULg; Malchair, Sandrine ULg

Poster (2011, September)

In Belgium, most drinking water is provided by calcareous karst aquifers. Chemical and microbiological characterisation of these systems focalises mainly on the transfer of pollutants and microbial ... [more ▼]

In Belgium, most drinking water is provided by calcareous karst aquifers. Chemical and microbiological characterisation of these systems focalises mainly on the transfer of pollutants and microbial contaminants, major sources of sanitary risks. These studies are generally based on bacterial cultures, representing however only 1% of bacterial species present in the environment. Molecular techniques allow the study of the global microbial diversity of an environment, as they are based on direct ADN extractions, without previous culturing steps. The objective of this research was the study of the microbial diversity in the ‘St Anne’ cave, Belgium. Chemical composition of the water, cultivable bacteria and the diversity of ammonia-oxydizing bacteria (AOB) were studied in waters and sediments of the ‘Chawresse’ (underground river in St Anne), on the cave’s wall and in soils aboveground. Bacterial counts revealed that most cultivable bacteria were associated with suspended particles and that their numbers decreased underground. Molecular analyses revealed the presence of AOB in the karst system. AOB are responsible for the first, acidifying step of the nitrification process. Further studies will specify and quantify their activity in this karst system. [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 ULg; Carnol, Monique ULg; Malchair, Sandrine ULg 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 detailDo we need to standardize extraction procedures for community level physiological profiling?
Carnol, Monique ULg; Bosman, Bernard ULg; Malchair, Sandrine ULg

Poster (2011, July)

Microorganisms are essential regulators of soil functioning, as they are involved in many crucial processes such as organic matter decomposition, nutrient cycling, soil structure and fertility. Currently ... [more ▼]

Microorganisms are essential regulators of soil functioning, as they are involved in many crucial processes such as organic matter decomposition, nutrient cycling, soil structure and fertility. Currently, there is a growing interest in functional diversity, such as the number and type of substrates used for energy metabolism (CLPP-community level physiological profiling). Such metabolic diversity of heterotroph soil bacteria is frequently investigated through Biolog Ecoplates, containing 31 of the most useful carbon sources for the soil community. The metabolic diversity of soil bacteria might be an interesting biological indicator of soil quality, and also a useful tool for investigating the link between land use change, climate warming, soil carbon, microbial diversity and activity. Methods related to Biolog-CLPP reported in the literature differ in the suspension medium and extraction method, the type and density of inoculums, the inoculation procedures and conditions of incubations. For example, various combinations of extraction methods and suspension media are being used for the first bacterial extraction step. Despite such methodological differences, Biolog-CLPP data are often compared across studies. The development of a standardised method for Biolog-CLPP is however essential improving the relevance and significance of results across studies. In this work, we investigated the influence of extraction procedures on microbial extraction efficiency for further use in CLPP. The microbial extraction efficiency was tested by plate counts for a total of twelve combinations of three suspension media and four extraction methods. The experiment was performed on four soils differing in organic matter content. The aims of this study were to: • Synthesize extraction procedures used for Biolog-CLPP • Measure the effect of extraction procedures on microbial extraction efficiency (plate counts) in four soil types • Investigate a possible interaction between the suspension media and the extraction method used • Evaluate whether a standardized extraction procedure can be recommended across soil types [less ▲]

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See detailHow do climate warming, plant species richness and plant functional group affect ammonia oxidizing bacteria diversity and function in experimental grasslands?
Malchair, Sandrine ULg; Carnol, Monique ULg

Poster (2011, June 27)

How do climate warming, plant species richness and plant functional group affect ammonia oxidizing bacteria diversity and function in experimental grasslands? Malchair S. and Carnol M. Laboratory of Plant ... [more ▼]

How do climate warming, plant species richness and plant functional group affect ammonia oxidizing bacteria diversity and function in experimental grasslands? Malchair S. and Carnol M. Laboratory of Plant and Microbial Ecology Department of Sciences and Environmental Management University of Liege, Belgium Background: There is increasing evidence of diversity-function relationship and impact of warming for aboveground vegetation. Belowground effects of warming and plant species richness remain however largely unknown, although bacteria regulate many soil processes and some groups, like ammonia oxidizing bacteria (AOB) were, have been suggested highly sensitive to environmental stress. Objectives: 1. Investigation of the response of AOB richness, community composition and function to warming, plant species richness and functional group 2. Exploration of the AOB richness-function link Methods: Soil samples were taken at 2 depths from grassland model ecosystems with different species richness levels (1, 3, 9) and temperature treatments (ambient, ambient+3°C). Selected species belonged to 3 plant functional groups: forbs, legumes and grasses. AOB function: potential nitrification assay (shaken soil slurry method) AOB diversity: polymerase chain reaction followed by denaturing gradient gel electrophoresis (PCR-DGGE) Results: 1. All retrieved AOB sequences were Nitrosospira-like ones 2. Warming had no effect on AOB richness and function 3. Higher plant species richness leads to increased AOB richness and modified community structure. AOB function was increased only at lower depth under warming 4. No difference in AOB richness between the plant functional groups 5. AOB community structure was different and AOB function higher under legumes. 6. The AOB richness-function link was negative under legumes. Conclusions: 1. Plant species influenced AOB richness and community composition. Plant functional group seems to be more important that species richness. 2. Legumes may impact AOB diversity and function through ammonia availability. [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 ULg; Carnol, Monique ULg; Malchair, Sandrine ULg 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 ULg; Guillaume, Patricia ULg; Carnol, Monique ULg

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 ULg; 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 detailAppréciation des indicateurs biologiques comme outils d'évaluation de la qualité des sols-rapport final de la convention ULg-SPW
Malchair, Sandrine ULg; Halen, Henri; Moutier, Marylène et al

Report (2010)

Résumé/Abstract Le Laboratoire d’Ecologie Végétale et Microbienne de l’Université de Liège a réalisé une recherche d’intérêt général ayant pour objet l’appréciation d’indicateurs biologiques permettant ... [more ▼]

Résumé/Abstract Le Laboratoire d’Ecologie Végétale et Microbienne de l’Université de Liège a réalisé une recherche d’intérêt général ayant pour objet l’appréciation d’indicateurs biologiques permettant d’évaluer la qualité des sols. Cette étude a été financée par le Service Public de Wallonie (SPW). Les données et les résultats de la présente convention sont la co-propriété du Service Public de Wallonie et du Laboratoire d’Ecologie Végétale et Microbienne (Prof. M. Carnol) de l’Université de Liège. Objet de la recherche : Les objectifs de ce projet sont l'appréciation d'indicateurs biologiques permettant d'évaluer la qualité des sols en réalisant : - Une recherche et synthèse bibliographique des études récentes sur la qualité biologique des sols, des techniques de mesure disponibles et de leurs conditions d'applications. Une attention particulière sera portée sur les indicateurs adaptés aux types de sols wallons, aux pratiques courantes de gestion des sols et aux problèmes environnementaux auxquels la Wallonie est le plus souvent confrontée (pollution par les métaux lourds, les HAP, les hydrocarbures). Cette synthèse permettra d'améliorer nos connaissances sur la pertinence de certaines mesures biologiques comme outil d'évaluation de la qualité des sols. - Un état des lieux des outils d'évaluation de la qualité biologique des sols dans les pays/régions voisins et de leur utilisation dans le cadre de politiques de gestion et/ou de protection des sols. Cet état des lieux a pour but d’explorer et d’analyser le cadre politique ainsi que les objectifs stratégiques poursuivis dans chacun des pays, les caractéristiques générales des différents réseaux existants, les indicateurs mis en œuvre ou suggérés, ainsi que les bases scientifiques justifiant le choix de ces indicateurs. - Une analyse de l'aptitude des outils identifiés aux points 1 et 2 à prédire la capacité des sols à remplir leurs fonctions écologiques, en ciblant trois domaines d'action de ces outils : sols forestiers, sols agricoles et sols potentiellement pollués. - Une évaluation des outils identifiés aux points 1 et 2 selon les critères suivants : sensibilité, reproductibilité, possibilité d'utilisation en routine, facilité d'interprétation, coût. - Des propositions pour la suite des travaux de recherche (liens avec la politique des sols, perspectives de recherche). Méthodes mises en œuvre : Pour la synthèse bibliographique, deux bases de données pertinentes dans le domaine des sciences du vivant et du sol (ISIWeb of Knowlege et ScienceDirect) ont été consultées. Les publications pertinentes dans le cadre de l’étude de la qualité des sols au moyen d’indicateurs biologiques ont été consultées afin de répertorier les indicateurs les plus étudiés et de synthétiser les données concernant la sensibilité de ces indicateurs vis-à-vis des pratiques de gestion agricole et forestière, de l’occupation des sols et de diverses pollutions. D’autres données relatives aux méthodologies employées, à la reproductibilité et l’interprétabilité des mesures on été acquises lors de cette recherche bibliographique. Concernant l’ état des lieux à propos des outils d'évaluation de la qualité biologique des sols existant dans les pays/régions voisin(e)s de la Belgique/Wallonie- réalisé par le bureau d’études RamSes-, le travail s’est effectué par exploration de la documentation technique spécialisée et par enquête. La pré-sélection des indicateurs pertinents pour l’application en Wallonie s’est effectuée sur base d’une approche numérique procédant par itération en considérant à la fois la pertinence et l’applicabilité des indicateurs (critères scientifiques), leur utilisation dans des réseaux existants, ainsi que des critères purement méthodologiques. Résultats : Sur base des définitions de la qualité des sols et des indicateurs biologiques, on peut considérer un indicateur biologique de la qualité d’un sol comme étant un organisme ou un processus biologique qui est l’indice précoce de modifications de l’environnement et dont les valeurs fournissent une information sur la capacité d’un sol à fonctionner comme un système vivant, au sein d’écosystèmes naturels ou gérés, dans le but de maintenir la productivité biologique, de maintenir ou d’augmenter la qualité de l’eau et de l’air et de promouvoir la santé des animaux, des végétaux et humaines. Après un inventaire de la diversité biologique des sols, nous nous sommes intéressés aux caractéristiques et occupations des sols en Wallonie pour aboutir à une sélection de combinaisons type de sol/type d’occupation pertinents dans le cadre d’un réseau de surveillance de la qualité biologique des sols. De plus, en fonction des types d’usage rencontrés en Wallonie, nous avons considéré les services écosystémiques majeurs remplis par le sol afin de pouvoir juger de la pertinence des indicateurs c'est-à-dire de leur capacité à intervenir dans les différents services rendus par le sol au travers de processus ou d’éléments biotiques avec comme bénéfices attendus la production de nourriture ou de fibre ainsi que le maintien d’un environnement sain. L’état des lieux des outils d’évaluation de la qualité biologique des sols dans les pays/régions voisins souligne que plusieurs pays en Europe –parmi lesquels les Pays-Bas, la Suisse, la France, le Royaume-Uni, l’Allemagne, l’Italie, l’Autriche, la Hongrie, la Tchéquie – ont mis en œuvre une démarche globalement similaire pour développer un système d’indicateurs et mettre en place un réseau de surveillance de la qualité biologique et/ou sur la biodiversité des sols de portée nationale. Ces démarches procèdent par étapes successives, à savoir : définition des objectifs du réseau de surveillance, propositions d’indicateurs (relevés bibliographiques), étape de pré-sélection de ces indicateurs, test de ces indicateurs et acquisitions de données de base (valeur de référence). Les réseaux mis en place poursuivent des objectifs stratégiques de surveillance et/ou de prévention mais aussi des objectifs scientifiques d’acquisition de données concernant la composante biologique des sols et ses fonctions spécifiques. Actuellement, seuls les Pays-Bas ont un réseau de surveillance de la qualité biologique des sols déjà en place et fonctionnel au niveau national. Les réseaux dans les autres pays sont soit au stade de test, soit fonctionnels à l’échelle régionale. En intégrant les données acquises au cours de cette recherche bibliographique et au cours de l’état des lieux des outils d’évaluation de la qualité biologique des sols dans les pays/régions voisins, les indicateurs biologiques de la qualité du sol sont majoritairement des paramètres microbiens. Les paramètres faunistiques sont moins fréquemment usités. Il ressort, également, de cet inventaire et de notre recherche bibliographique que les méthodes à développer et à mettre en place en Wallonie doivent se fonder sur une délimitation aussi claire que possible des objectifs poursuivis par les législateurs. En considérant, à l’issue de la recherche bibliographique, les critères de pertinence, d’applicabilité et de méthodologie, combinés à l’utilisation de l’indicateur dans des réseaux existants et à la consultation d’ouvrages de référence, nous avons pu mettre en avant six paramètres microbiens pertinents dans le cadre de la qualité des sols wallons, en tenant compte de l’usage agricole, forestier et urbain. Il s’agit de la biomasse microbienne, de paramètres relatifs à l’activité des micro-organismes du sol à savoir la respiration basale et la minéralisation nette de l’azote, et des indices écophysiologiques. Nous privilégions plutôt l’étude de la diversité fonctionnelle que celle de la diversité structurelle, car le lien entre la structure de la communauté microbienne et la fonction est encore mal établi. Ces différents paramètres sont d’ailleurs couramment employés/ recommandés comme indicateur biologique de la qualité des sols dans différents programmes de suivi des sols existant. Afin de prendre en considération la recommandation de l’union européenne suggérant d’intégrer des paramètres faunistiques dont l’étude de régulateurs biologiques (nématodes ou collemboles) et d’ingénieurs de l’écosystème (vers de terre) au programme de suivi des sols, nous proposons d’étudier le nombre et la biomasse des vers de terre comme paramètre faunistique, en raison de la simplicité d’étude de ce paramètre en comparaison de la complexité d’étude de la faune du sol au niveau taxonomique. L’application et le développement de politiques dans le cadre du décret relatif à la gestion des sols requièreront la mise en place d’indicateurs (notamment biologique) concernant la qualité des sols. Actuellement, aucune étude belge /wallone ne concerne l’étude de la qualité des sols de notre pays/région. D’autres pays européens (Pays-Bas, Allemagne, Italie, Tchéquie, la Hongrie, l’Autriche, ….) ont quant à eux débuté la mise en place du suivi de la qualité des sols faisant intervenir les indicateurs biologiques. Sur le plan opérationnel des perspectives tracées par le Plan d’Environnement pour le Développement Durable de 1994, qui prévoit « d'améliorer la connaissance et le suivi de la qualité des sols », il ressort de la revue d’état des lieux que la mise en œuvre fonctionnelle d’un réseau de mesures biologique cohérent est un processus lent, qui peut s’étaler sur 10 à 15 années. Cependant, les expériences – notamment en Grande-Bretagne - montrent également que les programmes de monitoring peuvent aussi s’initier de façon relativement simple, avec un nombre limité d’indicateurs et de points de mesure, et se complexifier par la suite en intégrant les résultats des efforts de recherche et pour la standardisation des méthodes. Sur base des éléments fournis conjointement à l’issue du travail d’analyse des indicateurs de la littérature et de l’état des lieux dans les pays et régions voisins, il est possible désormais de définir les principes d’un réseau minimum de démarrage et de définir les bases et méthodes de travail à développer par la suite pour consolider et étendre ce premier réseau. The Laboratory of Plant and Microbial Ecology of the University of Liege conducted a research of public interest focusing on the assessment of biological indicators for the evaluation of soil quality. This study was funded by the ’Service Public de Wallonie (SPW)’. Data and results are co-owned by the Service Public de Wallonie and the Laboratory of Plant and Microbial Ecology (Prof. M. Carnol), University of Liege. Research objectives : The objectives of this project were the assessment of biological indicators to estimate soil quality through : - A review and synthesis of recent scientific literature on biological soil quality, available methods and conditions of applicability. Particular attention will be paid on indicators relevant to the type of Walloon soils, to common soil management practices and environmental problems encountered in Wallonia (pollution by heavy metals, PAHs, hydrocarbons). This review will improve our knowledge on the relevance of some biological measures as tools for assessing soil quality. - An inventory of tools used for assessing the biological soil quality in neighbouring countries/regions and their use in management policies and / or soil protection. This inventory aims at exploring and analyzing the political and strategic objectives pursued in each country, the general characteristics of the different existing monitoring networks, the indicators used or suggested, as well as the scientific justification of these indicators. - An analysis of the appropriateness of the tools identified in the two first objectives to predict the capacity of soils to perform their ecological functions, targeting agricultural, forest and potentially polluted soils. - An assessment of the sensitivity, reproducibility, possibility of routine use, ease of understanding and cost of the selected tools. - Suggestions for future research (link to soil policy, research opportunities). Methods : For the literature review, we used two relevant databases for life and soil science (ISIWeb of Knowledge and ScienceDirect). Publications related to the assessment of soil quality through biological indicators were consulted in order to synthesize most frequently used indicators and their sensitivity to farm or forestry management, land use or pollution. Data on methodology, reproducibility and interpretability have also been synthesized. The inventory of tools used for assessing the biological quality soil in neighbouring countries/regions (realised by Ram-Ses), was performed through he exploration of technical and specialized publications and by inquiry. Pertinent indicators for the Walloon region were pre-selected through an iterative numerical approach taking into consideration the relevance and applicability of the indicators, their use in existing monitoring networks, and some methodological criteria. Results : Based on the definitions of soil quality and biological indicators, we can consider biological indicators of soil quality as organisms or biological processes reflecting a modification of the environment and whose values give information about the capacity of soil to function, within natural or managed ecosystem boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and support human health and habitation. After an inventory of soil biodiversity, we focused on soil characteristics and land use types to define the most relevant combinations of soil type/land use in the Walloon region. Furthermore, we considered the major soil ecosystem services provided by the most frequent land use types in Wallonia for evaluating the capacity of potential indicators to reflect these services through biota and biotic process (with benefits such as the production of food or fiber as well as maintaining a healthy environment). The inventory of tools used for assessing the biological soil quality in neighbouring countries/regions underlines that several European countries- including the Netherlands, Switzerland, France, the United Kingdom, Germany, Italy, Austria, Hungary, Czech Republic - have followed a broadly similar approach for developing indicators and establishing a monitoring network of the biological soil quality and / or soil biodiversity within a national scope. These approaches proceed by successive stages: definition of the objectives of the monitoring network, suggestion of indicators (literature revue), pre-selection of indicators, test of indicators and data acquisition (reference values). The established networks pursue strategic monitoring and / or prevention objectives, as well as scientific objectives such as data acquisition on the biological component of soils and its specific functions. Currently, only the Netherlands has a functional monitoring network at national level. Networks in other countries are either at the stage of test, or functional at the regional scale. The integration of the literature review and the inventory in neighboring countries/region, revealed that biological indicators of soil quality are mostly microbial parameters. Faunal parameters are less frequently used. Results also highlighted that the framework for developing a soil monitoring network in the Wallonia requires a clear definition of the objectives pursued by the legislator. Taking into account the literature review, the criteria of relevance, applicability and methodology, combined with the use of the indicator in existing networks and the consultation of reference books, we highlight six microbial parameters relevant in the context of soil quality in Wallonia, taking into account three major land use types (agriculture, forestry and urban). They are the microbial biomass, parameters related to the activity of soil microorganisms, namely basal respiration and net nitrogen mineralization, and ecophysiological indices. We recommend the study of functional diversity rather than structural diversity, because the link between microbial community structure and function is not yet well established. These parameters are also commonly used or recommended as biological indicators of soil quality in different soil monitoring networks. In line with the recommendations of the European Union, suggesting the integration of faunal parameters such as biological regulators (nematodes or collembola) and ecosystem engineers (earthworms) in soil monitoring programs, we suggest the number and biomass of earthworms , because of its simplicity in comparison to the study of soil fauna in taxonomic level. The application and policy development under the decree on soil management requires the establishment of indicators (including biological indicators) on soil quality. Currently, no Belgian / Walloon study exist on soil quality in our country / region. Other European countries (The Netherlands, Germany, Italy, Czech Republic, Hungary, Austria, ....) have begun setting up the monitoring of soil quality involving biological indicators. In relation to operational plans outlined by the ‘Plan d’Environnement pour le Développement Durable’ (Environmental Plan for Sustainable Development) in 1995, which intends “to improve the knowledge and the monitoring of soil quality”, it is clear from the inventory in neighboring countries that the establishment of a functional monitoring network is a slow process, spreading out over 10 to 15 years. However, experience- particularly in Great Britain- also reveals that a monitoring network can be initiated realtively easily, with a limited number of indicators and sampling points, and subsequently become more complex by integrating research results and from method standardization. Based on the evidence provided by the outcome of literature review and the inventory of tools used in neighboring countries, it is now possible to define the basic principles of a first monitoring network and define the basis and working methodology to consolidate and extent this first network. [less ▲]

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See detailLe rôle de la diversité biologique dans le fonctionnement des écosystèmes
Carnol, Monique ULg

Conference given outside the academic context (2010)

En cette ‘Année Internationale de la Biodiversité’ (ONU), la problématique de la conservation de la diversité biologique reçoit une attention élevée. Il ne fait plus aucun doute que les activités humaines ... [more ▼]

En cette ‘Année Internationale de la Biodiversité’ (ONU), la problématique de la conservation de la diversité biologique reçoit une attention élevée. Il ne fait plus aucun doute que les activités humaines sont responsables d’une perte accélérée de la diversité de la vie sur Terre. Or, la biodiversité est à la base des écosystèmes qui fournissent des services indispensables au bien-être humain, comme par exemple la l’approvisionnement en produits (nourriture, bois, médicaments..), la régulation du climat et de la qualité de l’eau, le support des cycles biogéochimiques. Mais qu’est ce que la biodiversité ? Ce terme a été utilisé si souvent et si librement que sa signification en devient obscure. Bien plus que la liste et la description des espèces vivantes, nous explorons dans cet exposé la signification de la biodiversité, ses différentes formes d’expression et son importance pour le fonctionnement des les écosystèmes. Cette approche permet de se rendre compte de l’intérêt que revêt la protection des espèces. Nous verrons aussi que le lien entre la diversité biologique et le fonctionnement des écosystèmes est loin d’être simple et que la répartition de la biodiversité sur terre est très hétérogène. [less ▲]

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See detailTree species effects on soil microbial activities in a young stand
Guillaume, Patricia ULg; Bazgir, Masoud; Carnol, Monique ULg 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 detailLes services écosystémiques dans les forêts mélangés et pures: perception des utilisateurs et connaissances scientifiques
Carnol, Monique ULg; Verheyen, Kris

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

Detailed reference viewed: 153 (11 ULg)
See detailEcosystem services in mixed forests and monocultures: comparing stakeholders’ perceptions and scientific knowledge
Carnol, Monique ULg; Branquart, Etienne; Muys, Bart et al

Conference (2010, March)

This study examines the common ground between current scientific knowledge and stakeholders’ perception of ecosystem services in mixed forests versus monocultures. An enquiry was performed within the ... [more ▼]

This study examines the common ground between current scientific knowledge and stakeholders’ perception of ecosystem services in mixed forests versus monocultures. An enquiry was performed within the frame of the project FORBIO aiming at the ‘Assessment of the effects of tree species BIOdiversity on FORest ecosystem functioning’ (http://forbio.biodiversity.be). The objective of this enquiry was to confront the perception of the influence of mixed species stands on ecosystem services in Belgium with actual scientific knowledge. The target groups were forest managers, users and scientists. As a general frame for the questionnaire, the ‘Millenium Ecosystem Assessment’, assessing the consequences of ecosystem change for human well-being, was selected. Respondents were asked to express their degree of agreement with statements related to the provisioning (production/quality, financial return), supporting (biodiversity, nutrient cycling, resistance), regulating (climate, air, soil, water) and cultural (aesthetics, recreation) ecosystem services, comparing mixed species to pure stands. Other questions addressed management objectives and the general profile of participants. The web-based questionnaires (SurveyMonkey) were established in Flemish and in French and invitations to respond were distributed by e-mail among key contact persons of forestry/nature associations, forest managers and scientists. After one month, a total of 142 and 228 responses were collected for the questionnaire in Flemish and in French, respectively. In this paper, we summarize main results by analyzing the profile of respondents and describing their perception of forest ecosystem services. Through the confrontation of this perception with the current scientific knowledge and through the identification of established scientific facts unknown to the general public, we identify gaps in scientific knowledge and ways of improving communication between scientists and managers. [less ▲]

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

Article for general public (2010)

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See detailModelling total soil respiration in agricultural soils.
Buysse, Pauline ULg; Goffin, Stéphanie; Carnol, Monique ULg et al

Poster (2010, January 12)

Soil respiration is a process which results in CO2 release from the soil to the atmosphere. It comprises two main components. The first one is heterotrophic respiration: CO2 is produced by soil ... [more ▼]

Soil respiration is a process which results in CO2 release from the soil to the atmosphere. It comprises two main components. The first one is heterotrophic respiration: CO2 is produced by soil microorganisms while decomposing the substrate. The second one is autotrophic respiration in which CO2 originates from roots and rhizospheric organisms. All the CO2 is then transported to the surface by diffusion (see Goffin et al., this session). Many biotic and abiotic factors play a role in soil respiration, making this process complex to analyze and understand. Temperature often appears as the most important driving variable. Besides that, interest in the future CO2 emissions from agricultural soils has been growing. Indeed, these ecosystems are a major concern from environmental, economic and social points of view. In particular, the choice of cultural practices and residue management techniques has a strong influence on CO2 emissions from agricultural systems. This work aims at getting to a better understanding of soil respiration in agricultural soils. To reach this goal, many semi-mechanistic models have been previously developed at very different spatio-temporal scales. We intend to adapt such an existing model to crop soils, within a spatial scale of a cultivated field and an annual temporal scale. The model will be validated by using flux measurements carried out at three different crop sites situated in the Hesbaye region in Belgium (Lonzée) and in the South West of France (Lamasquère, Auradé). The study was focused first on soil heterotrophic respiration. Within this part, short term sensitivity of this component to temperature was studied by means of a laboratory incubation experiment. This one was performed with soil samples taken at the Lonzée site. Among the many interesting results we got, it showed a clear sensitivity of soil heterotrophic respiration to short term temperature changes. In parallel, the soil heterotrophic model was calibrated on soil chamber measurements taken at the Lonzée site (Belgium). Next steps in this part of the work will be to calibrate the model using the data from the French sites, and finally to validate the model on the three sites. Afterwards, an autotrophic respiration submodel will be implemented and the results compared to field measurements carried out at the three sites. A further development could consist in simulating agricultural practices to take their impacts on CO2 emissions from crops into account. [less ▲]

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Peer Reviewed
See detailDo climate warming and plant species richness affect potential nitrification, basal respiration and ammonia-oxidizing bacteria in experimental grasslands?
Malchair, Sandrine ULg; De Boeck, Hans, J.; Lemmens, Catherine, M.H.M. et al

in Soil Biology & Biochemistry (2010), 42

Ammonia-oxidizing bacteria (AOB) are key organisms in the N cycle, as they control the first, rate-limiting step of the nitrification process. The question whether current environmental disturbances, such ... [more ▼]

Ammonia-oxidizing bacteria (AOB) are key organisms in the N cycle, as they control the first, rate-limiting step of the nitrification process. The question whether current environmental disturbances, such as climate warming and plant diversity losses, select for a particular community structure of AOB and/or influence their activity remains open. The purpose of this research was to study the impact of a 3 °C warming and of plant species richness (S) on microbial activity and diversity in synthesized grasslands, with emphasis on the nitrification process and on the diversity (community structure and richness) of ammonia-oxidizing bacteria (AOB).We measured soil chemical characteristics, basal respiration, potential nitrification and AOB diversity in soils under increasing plant species richness (S ¼ 1, S ¼ 3, S ¼ 9) at ambient and (ambient +3 °C) temperature. Species were drawn from a 9-species pool, belonging to three functional groups: forbs, legumes and grasses. Mixtures comprised species from each of the three functional groups. Warming did not affect AOB diversity and increased potential nitrification at S ¼ 3 only. Under warmed conditions, higher plant species richness resulted in increased potential nitrification rates. AOB richness increased with plant species richness. AOB community structure of monocultures under legumes differed from those under forbs and grasses. Clustering analysis revealed that AOB community structure under legume monocultures and mixtures of three and nine species grouped together. These results indicate that functional group identity rather than plant species richness influenced AOB community structure, especially through the presence of legumes. No clear relationship emerged between AOB richness and potential nitrification whatever plant species richness and temperature treatment. Our findings show a link between aboveground and belowground diversity, namely plant species richness, AOB richness and community structure. AOB richness was not related to soil processes, supporting the idea that increased diversity does not necessarily lead to increased rates of ecosystem processes. [less ▲]

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