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1. Alien invasive plants in Belgian limestone quarries

Author

Monty, A., Jorion, A., Pitz, C., Géron, C., and Mahy, G.

Subjects
Buddleja davidii, Senecio inaequidens, invasive species, mining, plant cover, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Description of the subject. Vegetation of high conservation value can establish in quarries, during or after exploitation. Alien plants could hamper this process and cause additional rehabilitation costs. However, the situation of plant invasion in quarries is largely unknown. Objectives. We aimed to assess alien plant invasion in active and abandoned quarries, and to identify the most invaded quarry sectors. Method. We surveyed 6,692 plots in 31 quarries in Belgium and recorded occurrence, density and cover of the 65 listed alien invasive plants in Belgium. Results. Fourteen species were recorded and 25 quarries contained at least one species. The two most occurring species, Buddleja davidii Franch. and Senecio inaequidens DC., were more widespread in quarries in activity. All sectors of the quarries were affected by alien plant invasion. Conclusions. Alien plant invasion in limestone quarries is highly variable, but significant. Considering the ecological potential of quarry sites, this issue should be better tackled.

Published
2019
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2. Agro-environmental scheme for segetal plant conservation in Wallonia (Belgium): an assessment in conventional and organic fields

Author

Lemoine, C., Sérusiaux, E., Mahy, G., and Piqueray, J.

Subjects
Segetal plants, environmental policies, biodiversity conservation, organic agriculture, conventional farming, Belgium, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Description of the subject. Segetal plant species are highly threatened in arable land. They are an integral part of agricultural history and biodiversity in Western Europe. In Wallonia (southern Belgium), an agro-environmental scheme (AES) has been adopted for their conservation. It consists of strips on a field margin, with at least 60% cereals in crop rotation, and proscribes spraying and fertilisation. Objectives. This paper assessed the impact of an AES on segetal species conservation. Method. In eight organic fields and six conventional fields, a vegetation survey was performed on an AES strip and on a control margin of each field. Evenness, richness, cover and species composition for both total and segetal species were compared between AES strips and their corresponding control margins. Also, a cover of pernicious weeds was considered to be a factor in the rejection of AES by farmers. Results. In conventional agriculture, species richness (total and segetal) and cover (total and segetal) were higher in the AES than in the respective control; however, pernicious weed cover was also enhanced. In organic fields, total species richness was higher and pernicious weed cover was lower in the AES than in the respective control. Total evenness was higher in organic than in conventional fields, due to the co-dominance of several species. Under the AES, species composition and abundance remained different between conventional and organic fields. In all cases, rare species were hardly found in our survey. Conclusions. AES promote plant diversity in both organic and conventional fields. Sowing AES strips with uncleaned seeds from well-preserved fields, or species introduction, are recommended to enhance rare species recovery.

Published
2018

3. Northern range edge equilibrium of Ambrosia artemisiifolia L. not achieved in Western Europe

Author

Ortmans, W., Mahy, G., and Monty, A.

Subjects
Geographical distribution, invasive species, interspecific competition, field experimentation, ecological factors, Helianthus annuus, Belgium, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Description of the subject. The geographic distributions of a species, be it native or alien, is expected to be limited at some point by environmental conditions. In this situation, a range edge equilibrium (REE) takes place, i.e., populations occurring beyond the edge have a growth rate reduced below replacement. The occurrence of REE has never been tested for an invasive species. In Western Europe, the invasive weed Ambrosia artemisiifolia L. has spread in most parts of southern and central France, where it can be found in very high densities in sunflower fields, but seems to be limited in its northwards expansion. It is currently unknown whether the range has reached a limit or not. Information about how the species responds to sunflower competition is also lacking. Objectives. This work addressed two questions: Has the northern part of A. artemisiifolia invaded range in Western Europe reached REE? How is A. artemisiifolia performance influenced by sunflower competition? Method. Plots were established in an agricultural field ca. 250 km north to the current invaded range, in Belgium. We planted A. artemisiifolia seedlings with or without sunflower competition. The following year, the population growth rates and the soil seed bank were assessed. Results. The species established populations with relatively high growth rates and soil seed bank. Sunflower competition did not have a significant impact on plant performance. Conclusions. The results invalidate the hypothesis of equilibrium at the current margin of A. artemisiifolia invaded range, and suggest a significant potential for invasion northwards.

Published
2017

4. Copper tolerance of three Crotalaria species from southeastern D.R. Congo at the early development stage

Author

Boisson, S., Le Stradic, S., Commans, M., Dumont, A., Leclerc, N., Thomas, C., and Mahy, G.

Subjects
Crotalaria, biodiversity conservation, indigenous organisms, seed germination, root length, in vitro experimentation, copper, soil chemicophysical properties, D.R. Congo, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Description of the subject. Microevolutionary processes in metallophytes established on copper enriched soils can lead to a diversity of plant species showing distinct tolerance capacities among genus. Researches about the relationship between these endangered plants and soil copper concentrations are critical in order to improve ex situ conservation methods in southeastern Democratic Republic of Congo (Katangan Copperbelt). Objectives. The aim of the study was to test the effect of copper on the germination and root elongation of three Crotalaria species naturally occurring along a natural copper gradient. The hypothesis is that copper concentrations have different effects on germination and root elongation according to the species of Crotalaria genus. Method. Three species were selected: Crotalaria cobalticola, Crotalaria peschiana and Crotalaria cornetii, occurring on soils with the highest to the lowest copper concentrations respectively. Germination and root elongation tests were performed in vitro (MS vitamin-enriched medium) in six copper mediums ranging from 0 to 125 µM Cu2+. Results. No significant differences in germination percentage were observed according to the copper concentrations. Crotalaria cornetii had the lowest germination percentage. Root elongation of C. peschiana did not differ with copper concentration, but root elongation of C. cobalticola was higher at the greatest copper concentration (125 µM Cu2+). Conclusions. Even if C. cobalticola presented better growth at highest Cu concentrations, it appeared that C. cobalticola and C. peschiana do not require copper for their early stages of development and could thus be conserved in non-contaminated substrate. Crotalaria cornetii seemed to present a physical seed dormancy.

Published
2016

6. Caractérisation des systèmes sols-plantes dans les collines de l'arc cuprifère du Katanga (synthèse bibliographique)

Author

Kaya Muyumba, D., Liénard, A., Mahy, G., Luhembwe, MN., and Colinet, G.

Subjects
Copper, cobalt, nutrient availability (soil), flora, Democratic Republic of the Congo, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Characterization of soil-plant systems in the hills of the copper belt in Katanga. A review. Introduction. The Copper belt of Katanga presents huge resources of Cu and Co-ore. On the copper hills of the area, mineralized rock outcrops and a specific flora have developed as a response to the high levels of Cu and Co in the soil. Soil-vegetation relationships need to be understood in order to develop biodiversity conservation programs prior to industrial mining of the copper hills. Literature. This paper reviews the current knowledge regarding soil characterization in the copper hills of Katanga and makes proposals for further research on the influence of the very specific chemical conditions of contaminated soils on the vegetation there. The focus is on the geochemical background and the bioavailability of Cu and Co. Much progress has been made recently regarding the identification of soil-vegetation relationships. Conclusions. Despite advances in this area, the issue of Cu and Co mobility within soil-plant systems is not yet entirely resolved.

Published
2015

7. Vers une synthèse de la conception et une définition des zones dans le gradient urbain-rural

Author

André, M., Mahy, G., Lejeune, P., and Bogaert, J.

Subjects
Urban areas, suburban areas, rural urban relations, ecology, terminology, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Toward a synthesis of the concept and a definition of the zones in the urban-rural gradient. The increasing footprint of urbanization on landscapes justifies the study of cities and the zones surrounding them. Paradoxically, the concepts relating to these zones remain unclear. Scientists from different disciplines diverge when defining these zones or their limits; they even often mention the zones without any definition. This practice excludes comparison between studies. By means of bibliographic research, the variety of terms used to describe the different zones composing the urban-rural gradient has been evidenced, as well as the characteristics of the zones themselves. They have been evaluated according to their relative importance and according to a series of criteria. Finally, new definitions for the different zones have been proposed in order to enable their identification in the field.

Published
2014

8. Importance de la méthode de coupe sur la régénération de Combretaceae du Bassin arachidier sénégalais

Author

Faye, E., Diallo, H., Samba, SAN., Touré, MA., Dramé, A., Fall, B., Lejoly, J., Diatta, M., Kaïré, M., De Cannière, C., Mahy, G., and Bogaert, J.

Subjects
Senegal, Combretum glutinosum, Guiera senegalensis, Stump sprouts, Agriculture
Abstract

Importance of the Harvest Method on the Regeneration of Combretaceae in the Senegalese Groundnut Basin. In order to develop recommendations for sustainable management of key fuel wood resources in the Senegalese Groundnut Basin, different diameters and heights of harvesting were tested on Guiera senegalensis J.F. Gmel and Combretum glutinosum Perr. The experimental design is adapted to the usual local harvesting period (May) and to the traditional tools (machete). Three factors were studied: species, height (ground level (RT), 20 and 50 cm) and diameter (0-10 and 10-20 cm). For each species, each treatment is represented by 15 individuals. Results from field observations and analysis of variance on the number of stems and growth variables (height and diameter) suggest a high survival rate (100%), a higher number of stems at 20 and 50 cm cutting height, a slow height growth of stems from ground level stumps (RT), and a larger diameter growth of G. senegalensis. For sustainable management of the studied Combreteceae species in the Groundnut Basin, 20 cm cutting height of all individuals would be appropriate.

Published
2013

9. Efficacité des méthodes de lutte contre le développement de cinq espèces de plantes invasives amphibies : Crassula helmsii, Hydrocotyle ranunculoides, Ludwigia grandiflora, Ludwigia peploides et Myriophyllum aquaticum (synthèse bibliographique)

Author

Delbart, E., Mahy, G., and Monty, A.

Subjects
Aquatic plant, invasion, management, chemical treatment, removal, eradication, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Effectiveness of techniques used to control the development of five invasive amphibious plant species: Crassula helmsii, Hydrocotyle ranunculoides, Ludwigia grandiflora, Ludwigia peploides and Myriophyllum aquaticum. A review. Among rapidly spreading invasive species in Europe, amphibious plants are particularly problematic. These plants are capable of developing a photosynthetic activity both below and above the water surface, and they typically form dense floating populations. Controlling amphibious plants, whether for the purposes of total eradication or for the regulation of their spread, represents an important challenge for managers. A literature review of existing control methods for Crassula helmsii, Hydrocotyle ranunculoides, Ludwigia grandiflora, Ludwigia peploides and Myriophyllum aquaticu was carried out, taking into account efficiency and costs. Of the 87 studies analyzed, a great variation was evident in the research efforts undertaken (number and spatial scale of studies) between species and between control methods. However, overall, the different control methods described showed a similar level of efficiency between species. Reports of total eradication of amphibious plants were rare. Such cases resulted from the application of mechanical or chemical methods, most often coupled with complementary methods such as manual finishing. The use of chemical control methods (less laborious and costly than others) was found to be frequently documented in the literature. However, except in the case of some active substances, such chemical methods were found to provide low control efficiency. Similarly, to date, biological control has not been found to provide convincing results. In addition, it should be noted that several biological control agents are considered as invasive species in Europe. On the other hand, although little related research has been carried out, methods such as manual or mechanical removal with manual finishing have often been found to result in satisfactory control levels. Aware of the difficulty of controlling amphibious plants, as well as the potential collateral damage caused by control methods to aquatic ecosystems, we argue that consensus still needs to be found between scientists, decision-makers and managers before decisions at regional or national scale can be made.

Published
2013

10. Compte-rendu et apport de la conférence-débat : 'Nature, conditionnalité et verdissement de la PAC : un tournant wallon ?', 9 novembre 2011, Espace Senghor, Gembloux, Belgique

Author

Piqueray, J., Richard, C., Walot, T., Le Roi, A., de Tillesse, M., Hance, T., and Mahy, G.

Subjects
CAP, biodiversity, agrarian reform, farmland, fallow, European Union, Belgium, France, Switzerland, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Proceedings of the conference: "Nature, conditionnalité et verdissement de la PAC : un tournant wallon ?". 9th November 2011. Espace Senghor, Gembloux, Belgium. Recently, the European Union (EU) proposed a reform project for the Common Agricultural Policy (CAP). One of the proposed reforms consists of imposing a set aside proportion of 7% of arable land for biodiversity support purposes. A conference on this proposal was held in Gembloux, Belgium, on 9th November 2011. Such a set aside system already exists in neighboring countries. The French and Swiss systems were presented at the conference in order to highlight their advantages and limitations. Scientific arguments underlying such policies were also presented. It was shown that the creation of semi-natural elements within the agricultural matrix is an efficient way to promote biodiversity. Both the quantity and the quality of these elements need to be considered. In addition, biodiversity is likely to provide services to agriculture, notably crop pollination and pest control. Currently, uncertainties remain regarding areas that are eligible to be designated as reaching the 7% threshold. However, based on the most probable scenarios, the current likely eligible areas cover only 4.3% of arable land in Wallonia. Less than 20% of Walloon farms already reach the 7% threshold proposed by the EU. If the European project is approved, it will therefore be of great importance to have some form of societal recognition afforded to farmers for their efforts. In order to optimize the positive effects of the policy on biodiversity, it is also imperative to ensure that a high level of biological quality is reached in the areas dedicated to biodiversity and to monitor this quality using clearly defined objectives. Economical, societal and environmental issues all need to be considered when applying this policy in order to improve agricultural sustainability and to stop the decline in biodiversity in agricultural landscapes.

Published
2013

11. Identité et écologie des espèces forestières commerciales d'Afrique centrale : le cas de Milicia spp. (synthèse bibliographique)

Author

Daïnou, K., Doucet, JL., Sinsin, B., and Mahy, G.

Subjects
Moraceae, forest trees, taxonomy, autecology, natural regeneration, genetic variation, Central Africa, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Identity and ecology of Central African timber tree species: the case of Milicia spp., a review. Iroko designates the two African tree species Milicia excelsa (Welw.) C.C.Berg and Milicia regia (A.Chev.) C.C.Berg known as highly valuable in the timber trade. Despite its economical importance and a decrease in population densities due to exploitation, there is a significant lack of ecological and sylvicultural knowledge required for a sustainable management of iroko. In West Africa, M. excelsa has received more attention from scientists than M. regia, but several topics clearly need further investigations or outcomes cannot be transferred in the context of Central African rainforests. A first thing to verify is whether speciation really occurred in the genus Milicia: morphological differences between the two species are very low, and a revision in this genus may lead to some rearrangements of conservatory and management policies related to this taxonomic group. Furthermore, (i) patterns related to the reproductive phenology and its controlling factors, (ii) gene flow among and between populations and individuals regarding life history traits, influence of human activities and paleoecological perturbations, and (iii) dynamics of seedling populations are among aspects that require emphasis in order to propose efficient tools for forest managers. Unless scientists provide these crucial data, the abundance of iroko in tropical rainforests will only depend on expensive plantations activities.

Published
2012

12. Phenotypic traits variation among native diploid, native tetraploid and invasive tetraploid Senecio inaequidens DC. (Asteraceae)

Author

Monty, A., Maurice, S., and Mahy, G.

Subjects
Senecio madagascariensis Poir., Senecio inaequidens DC., ploidy level, life history, common garden, alien plant, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Senecio inaequidens DC. is a rapidly spreading plant invader in Europe. In its native range, it occurs at two co-existing diploid and tetraploid cytotypes. To date, only tetraploids are reported in Europe, even though invasive diploids were recorded in other parts of the world. We compared native diploid and both native and invasive tetraploid populations in common gardens in Europe for a suite of life history traits. Diploids were able to develop, showed high biomass production and produced more flower heads than tetraploids. In contrast, winter survival was null for diploids. It was low for native tetraploids, but reached 40% in invasive tetraploids. Results suggested that diploid cytotype tends to an annual life form when grown in Western Europe, with earlier and more abundant flowering. In contrast, the tetraploid cytotype was mainly perennial which may enhance its invasiveness.

Published
2010

13. Restauration écologique : contexte, contraintes et indicateurs de suivi

Author

Mahy, G. and Cristofoli, S.

Subjects
Ecological restoration, filter, ecological reference, ecological trajectory, indicator, Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Abstract

Ecological restoration: context, constraints, and indicators. In a global context of growing anthropogenic disturbances on natural and semi-natural ecosystems, the only conservation of those ecosystems is not sufficient anymore. The ecological restoration may hence be an essential complement to conservation. The paper consists in a synthesis of scientific literature dedicated to the concepts of ecological restoration. We tackle the notion of restoration objectives, notably through the ecological reference. Besides the delimitation of clear objectives, the reference will enable the evaluation of restoration efforts by the use of indicators. The indicators may also provide information related to the attributes of the restored ecosystem and/or the followed ecological trajectory. Potential constraints faced by species through ecological filters could hence be detected and compensation measures could be proposed.

Published
2010

14. Editorial

Author

Mahy, G.

Subjects
Biotechnology, TP248.13-248.65, Environmental sciences, GE1-350
Published
2005

15. Floristic evidence for alternative biome states in tropical Africa

Author

Aleman, J. C., Fayolle, A., Favier, C., Staver, A. C., Dexter, K. G., Ryan, C. M., Azihou, A. F., Bauman, D., te Beest, M., Chidumayo, E. N., Comiskey, J. A., Cromsigt, J. P. G. M., Dessard, H., Doucet, J.-L., Finckh, M., Gillet, J.-F., Gourlet-Fleury, S., Hempson, G. P., Holdo, R. M., Kirunda, B., Kouame, F. N., Mahy, G., Maiato, F., Gonçalves, P., McNicol, I., Quintano, P. Nieto, Plumptre, A. J., Pritchard, R. C., Revermann, R., Schmitt, C. B., Swemmer, A. M., Talila, H., Woollen, E., and Swaine, M. D.

Published
2020

16. P1064 Upadacitinib is safe and effective in Ulcerative Colitis patients with prior exposure to Tofacitinib

Author

Gilmore, R, primary, Fernandes, R, additional, Hartley, I, additional, Arzivian, A, additional, Leong, R, additional, Andrew, B, additional, Vasudevan, A, additional, Greeve, T, additional, Moore, G, additional, Kim, S, additional, Lightowler, D, additional, Singh, A, additional, Mahy, G, additional, Mithanthaya, A, additional, Venugpal, K, additional, Han, S, additional, Bryant, R, additional, West, J, additional, Segal, J, additional, Christensen, B, additional, Ding, N J, additional, An, Y K, additional, and Begun, J, additional

Published
2024
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17. Explore before you restore: Incorporating complex systems thinking in ecosystem restoration.

Author

Maes, S. L., Perring, M. P., Cohen, R., Akinnifesi, F. K., Bargués‐Tobella, A., Bastin, J.‐F., Bauters, M., Bernardino, P. N., Brancalion, P. H. S., Bullock, J. M., Ellison, D., Fayolle, A., Fremout, T., Gann, G. D., Hishe, H., Holmgren, M., Ilstedt, U., Mahy, G., Messier, C., and Parr, C. L.

Subjects
RESTORATION ecology, SYSTEMS theory, ECOLOGICAL resilience, POLICY sciences, ECOSYSTEMS, ECOLOGICAL regime shifts
Abstract

Copyright of Journal of Applied Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2024
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20. Infliximab vs. adalimumab in Crohnʼs disease: results from 327 patients in an Australian and New Zealand observational cohort study

Author

Doecke, J. D., Hartnell, F., Bampton, P., Bell, S., Mahy, G., Grover, Z., Lewindon, P., Jones, L. V., Sewell, K., Krishnaprasad, K., Prosser, R., Marr, D., Fischer, J., R Thomas, G., Tehan, J. V., Ding, N. S., Cooke, S. E., Moss, K., Sechi, A., De Cruz, P., Grafton, R., Connor, S. J., Lawrance, I. C., Gearry, R. B., Andrews, J. M., and RadfordSmith, G. L.

Published
2017
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25. Comparative performances of machine learning methods for classifying Crohn Disease patients using genome-wide genotyping data

Author

Romagnoni, A., Jegou, S., Van Steen, K., Wainrib, G., Hugot, J. -P., Peyrin-Biroulet, L., Chamaillard, M., Colombel, J. -F., Cottone, M., D'Amato, M., D'Inca, R., Halfvarson, J., Henderson, P., Karban, A., Kennedy, N. A., Khan, M. A., Lemann, M., Levine, A., Massey, D., Milla, M., S. M. E., Ng, Oikonomou, I., Peeters, H., Proctor, D. D., Rahier, J. -F., Rutgeerts, P., Seibold, F., Stronati, L., Taylor, K. M., Torkvist, L., Ublick, K., Van Limbergen, J., Van Gossum, A., Vatn, M. H., Zhang, H., Zhang, W., Andrews, J. M., Bampton, P. A., Barclay, M., Florin, T. H., Gearry, R., Krishnaprasad, K., Lawrance, I. C., Mahy, G., Montgomery, G. W., Radford-Smith, G., Roberts, R. L., Simms, L. A., Hanigan, K., Croft, A., Amininijad, L., Cleynen, I., Dewit, O., Franchimont, D., Georges, M., Laukens, D., Theatre, E., Vermeire, S., Aumais, G., Baidoo, L., Barrie, A. M., Beck, K., Bernard, E. -J., Binion, D. G., Bitton, A., Brant, S. R., Cho, J. H., Cohen, A., Croitoru, K., Daly, M. J., Datta, L. W., Deslandres, C., Duerr, R. H., Dutridge, D., Ferguson, J., Fultz, J., Goyette, P., Greenberg, G. R., Haritunians, T., Jobin, G., Katz, S., Lahaie, R. G., Mcgovern, D. P., Nelson, L., S. M., Ng, Ning, K., Pare, P., Regueiro, M. D., Rioux, J. D., Ruggiero, E., Schumm, L. P., Schwartz, M., Scott, R., Sharma, Y., Silverberg, M. S., Spears, D., Steinhart, A. H., Stempak, J. M., Swoger, J. M., Tsagarelis, C., Zhang, C., Zhao, H., Aerts, J., Ahmad, T., Arbury, H., Attwood, A., Auton, A., Ball, S. G., Balmforth, A. J., Barnes, C., Barrett, J. C., Barroso, I., Barton, A., Bennett, A. J., Bhaskar, S., Blaszczyk, K., Bowes, J., Brand, O. J., Braund, P. S., Bredin, F., Breen, G., Brown, M. J., Bruce, I. N., Bull, J., Burren, O. S., Burton, J., Byrnes, J., Caesar, S., Cardin, N., Clee, C. M., Coffey, A. J., MC Connell, J., Conrad, D. F., Cooper, J. D., Dominiczak, A. F., Downes, K., Drummond, H. E., Dudakia, D., Dunham, A., Ebbs, B., Eccles, D., Edkins, S., Edwards, C., Elliot, A., Emery, P., Evans, D. M., Evans, G., Eyre, S., Farmer, A., Ferrier, I. N., Flynn, E., Forbes, A., Forty, L., Franklyn, J. A., Frayling, T. M., Freathy, R. M., Giannoulatou, E., Gibbs, P., Gilbert, P., Gordon-Smith, K., Gray, E., Green, E., Groves, C. J., Grozeva, D., Gwilliam, R., Hall, A., Hammond, N., Hardy, M., Harrison, P., Hassanali, N., Hebaishi, H., Hines, S., Hinks, A., Hitman, G. A., Hocking, L., Holmes, C., Howard, E., Howard, P., Howson, J. M. M., Hughes, D., Hunt, S., Isaacs, J. D., Jain, M., Jewell, D. P., Johnson, T., Jolley, J. D., Jones, I. R., Jones, L. A., Kirov, G., Langford, C. F., Lango-Allen, H., Lathrop, G. M., Lee, J., Lee, K. L., Lees, C., Lewis, K., Lindgren, C. M., Maisuria-Armer, M., Maller, J., Mansfield, J., Marchini, J. L., Martin, P., Massey, D. C., Mcardle, W. L., Mcguffin, P., Mclay, K. E., Mcvean, G., Mentzer, A., Mimmack, M. L., Morgan, A. E., Morris, A. P., Mowat, C., Munroe, P. B., Myers, S., Newman, W., Nimmo, E. R., O'Donovan, M. C., Onipinla, A., Ovington, N. R., Owen, M. J., Palin, K., Palotie, A., Parnell, K., Pearson, R., Pernet, D., Perry, J. R., Phillips, A., Plagnol, V., Prescott, N. J., Prokopenko, I., Quail, M. A., Rafelt, S., Rayner, N. W., Reid, D. M., Renwick, A., Ring, S. M., Robertson, N., Robson, S., Russell, E., Clair, D. S., Sambrook, J. G., Sanderson, J. D., Sawcer, S. J., Schuilenburg, H., Scott, C. E., Seal, S., Shaw-Hawkins, S., Shields, B. M., Simmonds, M. J., Smyth, D. J., Somaskantharajah, E., Spanova, K., Steer, S., Stephens, J., Stevens, H. E., Stirrups, K., Stone, M. A., Strachan, D. P., Su, Z., Symmons, D. P. M., Thompson, J. R., Thomson, W., Tobin, M. D., Travers, M. E., Turnbull, C., Vukcevic, D., Wain, L. V., Walker, M., Walker, N. M., Wallace, C., Warren-Perry, M., Watkins, N. A., Webster, J., Weedon, M. N., Wilson, A. G., Woodburn, M., Wordsworth, B. P., Yau, C., Young, A. H., Zeggini, E., Brown, M. A., Burton, P. R., Caulfield, M. J., Compston, A., Farrall, M., Gough, S. C. L., Hall, A. S., Hattersley, A. T., Hill, A. V. S., Mathew, C. G., Pembrey, M., Satsangi, J., Stratton, M. R., Worthington, J., Hurles, M. E., Duncanson, A., Ouwehand, W. H., Parkes, M., Rahman, N., Todd, J. A., Samani, N. J., Kwiatkowski, D. P., Mccarthy, M. I., Craddock, N., Deloukas, P., Donnelly, P., Blackwell, J. M., Bramon, E., Casas, J. P., Corvin, A., Jankowski, J., Markus, H. S., Palmer, C. N., Plomin, R., Rautanen, A., Trembath, R. C., Viswanathan, A. C., Wood, N. W., Spencer, C. C. A., Band, G., Bellenguez, C., Freeman, C., Hellenthal, G., Pirinen, M., Strange, A., Blackburn, H., Bumpstead, S. J., Dronov, S., Gillman, M., Jayakumar, A., Mccann, O. T., Liddle, J., Potter, S. C., Ravindrarajah, R., Ricketts, M., Waller, M., Weston, P., Widaa, S., Whittaker, P., Romagnoni, A., Jegou, S., Van Steen, K., Wainrib, G., Hugot, J. -P., Peyrin-Biroulet, L., Chamaillard, M., Colombel, J. -F., Cottone, M., D'Amato, M., D'Inca, R., Halfvarson, J., Henderson, P., Karban, A., Kennedy, N. A., Khan, M. A., Lemann, M., Levine, A., Massey, D., Milla, M., Ng, S. M. E., Oikonomou, I., Peeters, H., Proctor, D. D., Rahier, J. -F., Rutgeerts, P., Seibold, F., Stronati, L., Taylor, K. M., Torkvist, L., Ublick, K., Van Limbergen, J., Van Gossum, A., Vatn, M. H., Zhang, H., Zhang, W., Andrews, J. M., Bampton, P. A., Barclay, M., Florin, T. H., Gearry, R., Krishnaprasad, K., Lawrance, I. C., Mahy, G., Montgomery, G. W., Radford-Smith, G., Roberts, R. L., Simms, L. A., Hanigan, K., Croft, A., Amininijad, L., Cleynen, I., Dewit, O., Franchimont, D., Georges, M., Laukens, D., Theatre, E., Vermeire, S., Aumais, G., Baidoo, L., Barrie, A. M., Beck, K., Bernard, E. -J., Binion, D. G., Bitton, A., Brant, S. R., Cho, J. H., Cohen, A., Croitoru, K., Daly, M. J., Datta, L. W., Deslandres, C., Duerr, R. H., Dutridge, D., Ferguson, J., Fultz, J., Goyette, P., Greenberg, G. R., Haritunians, T., Jobin, G., Katz, S., Lahaie, R. G., Mcgovern, D. P., Nelson, L., Ng, S. M., Ning, K., Pare, P., Regueiro, M. D., Rioux, J. D., Ruggiero, E., Schumm, L. P., Schwartz, M., Scott, R., Sharma, Y., Silverberg, M. S., Spears, D., Steinhart, A. H., Stempak, J. M., Swoger, J. M., Tsagarelis, C., Zhang, C., Zhao, H., Aerts, J., Ahmad, T., Arbury, H., Attwood, A., Auton, A., Ball, S. G., Balmforth, A. J., Barnes, C., Barrett, J. C., Barroso, I., Barton, A., Bennett, A. J., Bhaskar, S., Blaszczyk, K., Bowes, J., Brand, O. J., Braund, P. S., Bredin, F., Breen, G., Brown, M. J., Bruce, I. N., Bull, J., Burren, O. S., Burton, J., Byrnes, J., Caesar, S., Cardin, N., Clee, C. M., Coffey, A. J., MC Connell, J., Conrad, D. F., Cooper, J. D., Dominiczak, A. F., Downes, K., Drummond, H. E., Dudakia, D., Dunham, A., Ebbs, B., Eccles, D., Edkins, S., Edwards, C., Elliot, A., Emery, P., Evans, D. M., Evans, G., Eyre, S., Farmer, A., Ferrier, I. N., Flynn, E., Forbes, A., Forty, L., Franklyn, J. A., Frayling, T. M., Freathy, R. M., Giannoulatou, E., Gibbs, P., Gilbert, P., Gordon-Smith, K., Gray, E., Green, E., Groves, C. J., Grozeva, D., Gwilliam, R., Hall, A., Hammond, N., Hardy, M., Harrison, P., Hassanali, N., Hebaishi, H., Hines, S., Hinks, A., Hitman, G. A., Hocking, L., Holmes, C., Howard, E., Howard, P., Howson, J. M. M., Hughes, D., Hunt, S., Isaacs, J. D., Jain, M., Jewell, D. P., Johnson, T., Jolley, J. D., Jones, I. R., Jones, L. A., Kirov, G., Langford, C. F., Lango-Allen, H., Lathrop, G. M., Lee, J., Lee, K. L., Lees, C., Lewis, K., Lindgren, C. M., Maisuria-Armer, M., Maller, J., Mansfield, J., Marchini, J. L., Martin, P., Massey, D. C., Mcardle, W. L., Mcguffin, P., Mclay, K. E., Mcvean, G., Mentzer, A., Mimmack, M. L., Morgan, A. E., Morris, A. P., Mowat, C., Munroe, P. B., Myers, S., Newman, W., Nimmo, E. R., O'Donovan, M. C., Onipinla, A., Ovington, N. R., Owen, M. J., Palin, K., Palotie, A., Parnell, K., Pearson, R., Pernet, D., Perry, J. R., Phillips, A., Plagnol, V., Prescott, N. J., Prokopenko, I., Quail, M. A., Rafelt, S., Rayner, N. W., Reid, D. M., Renwick, A., Ring, S. M., Robertson, N., Robson, S., Russell, E., Clair, D. S., Sambrook, J. G., Sanderson, J. D., Sawcer, S. J., Schuilenburg, H., Scott, C. E., Seal, S., Shaw-Hawkins, S., Shields, B. M., Simmonds, M. J., Smyth, D. J., Somaskantharajah, E., Spanova, K., Steer, S., Stephens, J., Stevens, H. E., Stirrups, K., Stone, M. A., Strachan, D. P., Su, Z., Symmons, D. P. M., Thompson, J. R., Thomson, W., Tobin, M. D., Travers, M. E., Turnbull, C., Vukcevic, D., Wain, L. V., Walker, M., Walker, N. M., Wallace, C., Warren-Perry, M., Watkins, N. A., Webster, J., Weedon, M. N., Wilson, A. G., Woodburn, M., Wordsworth, B. P., Yau, C., Young, A. H., Zeggini, E., Brown, M. A., Burton, P. R., Caulfield, M. J., Compston, A., Farrall, M., Gough, S. C. L., Hall, A. S., Hattersley, A. T., Hill, A. V. S., Mathew, C. G., Pembrey, M., Satsangi, J., Stratton, M. R., Worthington, J., Hurles, M. E., Duncanson, A., Ouwehand, W. H., Parkes, M., Rahman, N., Todd, J. A., Samani, N. J., Kwiatkowski, D. P., Mccarthy, M. I., Craddock, N., Deloukas, P., Donnelly, P., Blackwell, J. M., Bramon, E., Casas, J. P., Corvin, A., Jankowski, J., Markus, H. S., Palmer, C. N., Plomin, R., Rautanen, A., Trembath, R. C., Viswanathan, A. C., Wood, N. W., Spencer, C. C. A., Band, G., Bellenguez, C., Freeman, C., Hellenthal, G., Pirinen, M., Strange, A., Blackburn, H., Bumpstead, S. J., Dronov, S., Gillman, M., Jayakumar, A., Mccann, O. T., Liddle, J., Potter, S. C., Ravindrarajah, R., Ricketts, M., Waller, M., Weston, P., Widaa, S., Whittaker, P., Daly, Mark J. [0000-0002-0949-8752], Apollo - University of Cambridge Repository, Hugot, Jean-Pierre [0000-0002-8446-6056], UCL - SSS/IREC/GAEN - Pôle d'Hépato-gastro-entérologie, UCL - (MGD) Service de gastro-entérologie, Romagnoni, A, Jegou, S, VAN STEEN, Kristel, Wainrib, G, Hugot, JP, Peyrin-Biroulet, L, Chamaillard, M, Colombel, JF, Cottone, M, D'Amato, M, D'Inca, R, Halfvarson, J, Henderson, P, Karban, A, Kennedy, NA, Khan, MA, Lemann, M, Levine, A, Massey, D, Milla, M, Ng, SME, Oikonomou, I, Peeters, H, Proctor, DD, Rahier, JF, Rutgeerts, P, Seibold, F, Stronati, L, Taylor, KM, Torkvist, L, Ublick, K, Van Limbergen, J, Van Gossum, A, Vatn, MH, Zhang, H, Zhang, W, Andrews, JM, Bampton, PA, Barclay, M, Florin, TH, Gearry, R, Krishnaprasad, K, Lawrance, IC, Mahy, G, Montgomery, GW, Radford-Smith, G, Roberts, RL, Simms, LA, Hanigan, K, Croft, A, Amininijad, L, Cleynen, I, Dewit, O, Franchimont, D, Georges, M, Laukens, D, Theatre, E, Vermeire, S, Aumais, G, Baidoo, L, Barrie, AM, Beck, K, Bernard, EJ, Binion, DG, Bitton, A, Brant, SR, Cho, JH, Cohen, A, Croitoru, K, Daly, MJ, Datta, LW, Deslandres, C, Duerr, RH, Dutridge, D, Ferguson, J, Fultz, J, Goyette, P, Greenberg, GR, Haritunians, T, Jobin, G, Katz, S, Lahaie, RG, McGovern, DP, Nelson, L, Ng, SM, Ning, K, Pare, P, Regueiro, MD, Rioux, JD, Ruggiero, E, Schumm, LP, Schwartz, M, Scott, R, Sharma, Y, Silverberg, MS, Spears, D, Steinhart, AH, Stempak, JM, Swoger, JM, Tsagarelis, C, Zhang, C, Zhao, HY, AERTS, Jan, Ahmad, T, Arbury, H, Attwood, A, Auton, A, Ball, SG, Balmforth, AJ, Barnes, C, Barrett, JC, Barroso, I, Barton, A, Bennett, AJ, Bhaskar, S, Blaszczyk, K, Bowes, J, Brand, OJ, Braund, PS, Bredin, F, Breen, G, Brown, MJ, Bruce, IN, Bull, J, Burren, OS, Burton, J, Byrnes, J, Caesar, S, Cardin, N, Clee, CM, Coffey, AJ, Mc Connell, J, Conrad, DF, Cooper, JD, Dominiczak, AF, Downes, K, Drummond, HE, Dudakia, D, Dunham, A, Ebbs, B, Eccles, D, Edkins, S, Edwards, C, Elliot, A, Emery, P, Evans, DM, Evans, G, Eyre, S, Farmer, A, Ferrier, IN, Flynn, E, Forbes, A, Forty, L, Franklyn, JA, Frayling, TM, Freathy, RM, Giannoulatou, E, Gibbs, P, Gilbert, P, Gordon-Smith, K, Gray, E, Green, E, Groves, CJ, Grozeva, D, Gwilliam, R, Hall, A, Hammond, N, Hardy, M, Harrison, P, Hassanali, N, Hebaishi, H, Hines, S, Hinks, A, Hitman, GA, Hocking, L, Holmes, C, Howard, E, Howard, P, Howson, JMM, Hughes, D, Hunt, S, Isaacs, JD, Jain, M, Jewell, DP, Johnson, T, Jolley, JD, Jones, IR, Jones, LA, Kirov, G, Langford, CF, Lango-Allen, H, Lathrop, GM, Lee, J, Lee, KL, Lees, C, Lewis, K, Lindgren, CM, Maisuria-Armer, M, Maller, J, Mansfield, J, Marchini, JL, Martin, P, Massey, DCO, McArdle, WL, McGuffin, P, McLay, KE, McVean, G, Mentzer, A, Mimmack, ML, Morgan, AE, Morris, AP, Mowat, C, Munroe, PB, Myers, S, Newman, W, Nimmo, ER, O'Donovan, MC, Onipinla, A, Ovington, NR, Owen, MJ, Palin, K, Palotie, A, Parnell, K, Pearson, R, Pernet, D, Perry, JRB, Phillips, A, Plagnol, V, Prescott, NJ, Prokopenko, I, Quail, MA, Rafelt, S, Rayner, NW, Reid, DM, Renwick, A, Ring, SM, Robertson, N, Robson, S, Russell, E, St Clair, D, Sambrook, JG, Sanderson, JD, Sawcer, SJ, Schuilenburg, H, Scott, CE, Seal, S, Shaw-Hawkins, S, Shields, BM, Simmonds, MJ, Smyth, DJ, Somaskantharajah, E, Spanova, K, Steer, S, Stephens, J, Stevens, HE, Stirrups, K, Stone, MA, Strachan, DP, Su, Z, Symmons, DPM, Thompson, JR, Thomson, W, Tobin, MD, Travers, ME, Turnbull, C, Vukcevic, D, Wain, LV, Walker, M, Walker, NM, Wallace, C, Warren-Perry, M, Watkins, NA, Webster, J, Weedon, MN, Wilson, AG, Woodburn, M, Wordsworth, BP, Yau, C, Young, AH, Zeggini, E, Brown, MA, Burton, PR, Caulfield, MJ, Compston, A, Farrall, M, Gough, SCL, Hall, AS, Hattersley, AT, Hill, AVS, Mathew, CG, Pembrey, M, Satsangi, J, Stratton, MR, Worthington, J, Hurles, ME, Duncanson, A, Ouwehand, WH, Parkes, M, Rahman, N, Todd, JA, Samani, NJ, Kwiatkowski, DP, McCarthy, MI, Craddock, N, Deloukas, P, Donnelly, P, Blackwell, JM, Bramon, E, Casas, JP, Corvin, A, Jankowski, J, Markus, HS, Palmer, CNA, Plomin, R, Rautanen, A, Trembath, RC, Viswanathan, AC, Wood, NW, Spencer, CCA, Band, G, Bellenguez, C, Freeman, C, Hellenthal, G, Pirinen, M, Strange, A, Blackburn, H, Bumpstead, SJ, Dronov, S, Gillman, M, Jayakumar, A, McCann, OT, Liddle, J, Potter, SC, Ravindrarajah, R, Ricketts, M, Waller, M, Weston, P, Widaa, S, Whittaker, P, and Kwiatkowski, D

Subjects
Male, 692/4020/1503/257/1402, Genotype, Genotyping Techniques, LOCI, 45/43, lcsh:Medicine, Polymorphism, Single Nucleotide, Crohn's disease, genetics, genome wide association, Article, Deep Learning, Crohn Disease, INDEL Mutation, Genetics research, Humans, genetics, Genetic Predisposition to Disease, 129, lcsh:Science, Alleles, Science & Technology, genome wide association, RISK PREDICTION, 45, Models, Genetic, lcsh:R, Decision Trees, 692/308/2056, ASSOCIATION, Multidisciplinary Sciences, Crohn's disease, Logistic Models, Nonlinear Dynamics, ROC Curve, Area Under Curve, Science & Technology - Other Topics, lcsh:Q, Female, Neural Networks, Computer, INFLAMMATORY-BOWEL-DISEASE, Genome-Wide Association Study
Abstract

Crohn Disease (CD) is a complex genetic disorder for which more than 140 genes have been identified using genome wide association studies (GWAS). However, the genetic architecture of the trait remains largely unknown. The recent development of machine learning (ML) approaches incited us to apply them to classify healthy and diseased people according to their genomic information. The Immunochip dataset containing 18,227 CD patients and 34,050 healthy controls enrolled and genotyped by the international Inflammatory Bowel Disease genetic consortium (IIBDGC) has been re-analyzed using a set of ML methods: penalized logistic regression (LR), gradient boosted trees (GBT) and artificial neural networks (NN). The main score used to compare the methods was the Area Under the ROC Curve (AUC) statistics. The impact of quality control (QC), imputing and coding methods on LR results showed that QC methods and imputation of missing genotypes may artificially increase the scores. At the opposite, neither the patient/control ratio nor marker preselection or coding strategies significantly affected the results. LR methods, including Lasso, Ridge and ElasticNet provided similar results with a maximum AUC of 0.80. GBT methods like XGBoost, LightGBM and CatBoost, together with dense NN with one or more hidden layers, provided similar AUC values, suggesting limited epistatic effects in the genetic architecture of the trait. ML methods detected near all the genetic variants previously identified by GWAS among the best predictors plus additional predictors with lower effects. The robustness and complementarity of the different methods are also studied. Compared to LR, non-linear models such as GBT or NN may provide robust complementary approaches to identify and classify genetic markers. Tis work was supported by Fondation pour la Recherche Médical (ref DEI20151234405) and Investissements d’Avenir programme ANR-11-IDEX-0005-02, Sorbonne Paris Cite, Laboratoire d’excellence INFLAMEX. Te authors thank the students that participated to the wisdom of the crowd exercise.

Published
2019

27. P399 Higher anti-tumour necrosis factor-alpha drug levels are associated with improved radiological outcomes in patients with perianal fistulising Crohn’s disease: A retrospective multi-centre study

Author

De Gregorio, M, primary, Lee, T, additional, Krishnaprasad, K, additional, Amos, G, additional, An, Y K, additional, Bastian-Jordan, M, additional, Begun, J, additional, Borok, N, additional, Brown, D J M, additional, Cheung, W, additional, Connor, S, additional, Gerstenmaier, J, additional, Gilbert, L E, additional, Gilmore, R, additional, Gu, B, additional, Kutaiba, N, additional, Lee, A, additional, Mahy, G, additional, Srinivasan, A, additional, Thin, L, additional, Thompson, A, additional, Welman, C J, additional, Yong, E X, additional, De Cruz, P, additional, van Langenberg, D, additional, Sparrow co-lead senior author, M, additional, and Ding, N S, additional

Published
2021
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36. IBD risk loci are enriched in multigenic regulatory modules encompassing putative causative genes

Author

Momozawa, Y, Dmitrieva, J, Theatre, E, Deffontaine, V, Rahmouni, S, Charloteaux, B, Crins, F, Docampo, E, Elansary, M, Gori, AS, Lecut, C, Mariman, R, Mni, M, Oury, C, Altukhov, I, Alexeev, D, Aulchenko, Y, Amininejad, L, Bouma, G, Hoentjen, F, Lowenberg, M, Oldenburg, B, Pierik, MJ, de Jong, AE, van der Woude, C.J., Visschedijk, MC, Lathrop, M, Hugot, JP, Weersma, RK, Vos, M, Franchimont, D, Vermeire, S, Kubo, M, Louis, E, Georges, M, Abraham, C, Achkar, JP, Ahmad, T, Ananthakrishnan, AN, Andersen, V, Anderson, CA, Andrews, JM, Annese, V, Aumais, G, Baidoo, L, Baldassano, RN, Bampton, PA, Barclay, M, Barrett, JC, Bayless, TM, Bethge, J, Bitton, A, Boucher, G, Brand, S, Brandt, B, Brant, SR, Buning, C, Chew, A, Cho, JH, Cleynen, I, Cohain, A, Croft, A, Daly, MJ, D'Amato, M, Danese, S, Jong, D, Denapiene, G, Denson, LA, Devaney, KL, Dewit, O, D'Inca, R, Dubinsky, M, Duerr, RH, Edwards, C, Ellinghaus, D, Essers, J, Ferguson, LR, Festen, EA, Fleshner, P, Florin, T, Franke, A, Fransen, K, Gearry, R, Gieger, C, Glas, J, Goyette, P, Green, T, Griffiths, AM, Guthery, SL, Hakonarson, H, Halfvarson, J, Hanigan, K, Haritunians, T, de Hart, A, Hawkey, C, Hayward, NK, Hedl, M, Henderson, P, Hu, XH, Huang, HL, Hui, KY, Imielinski, M, Ippoliti, A, Jonaitis, L, Jostins, L, Karlsen, TH, Kennedy, NA, Khan, MA, Kiudelis, G, Krishnaprasad, K, Kugathasan, S, Kupcinskas, L, Latiano, A, Laukens, D, Lawrance, IC, Lee, JC, Lees, CW, Leja, M, van Limbergen, J, Lionetti, P, Liu, JZ, Mahy, G, Mansfield, J, Massey, D, Mathew, CG, McGovern, DPB, Milgrom, R, Mitrovic, M, Montgomery, GW, Mowat, C, Newman, W, Ng, A, Ng, SC, Ng, SME, Nikolaus, S, Ning, K, Nothen, M, Oikonomou, I, Palmieri, O, Parkes, M, Phillips, A, Ponsioen, CY, Potocnik, U, Prescott, NJ, Proctor, DD, Radford-Smith, G, Rahier, JF, Raychaudhuri, S, Regueiro, M, Rieder, F, Rioux, JD, Ripke, S, Roberts, R, Russell, RK, Sanderson, JD, Sans, M, Satsangi, J, Schadt, EE, Schreiber, S, Schulte, D, Schumm, LP, Scott, R, Seielstad, M, Sharma, Y, Silverberg, MS, Simms, LA, Skieceviciene, J, Spain, SL, Steinhart, AH, Stempak, JM, Stronati, L, Sventoraityte, J, Targan, SR, Taylor, KM, Velde, A, Torkvist, L, Tremelling, M, van Sommeren, S, Vasiliauskas, E, Verspaget, HW, Walters, T, Wang, K, Wang, MH, Wei, Z, Whiteman, D, Wijmenga, C, Wilson, DC, Winkelmann, J, Xavier, RJ, Zhang, B, Zhang, CK, Zhang, H, Zhang, W, Zhao, HY, Zhao, ZZ, Momozawa, Y, Dmitrieva, J, Theatre, E, Deffontaine, V, Rahmouni, S, Charloteaux, B, Crins, F, Docampo, E, Elansary, M, Gori, A, Lecut, C, Mariman, R, Mni, M, Oury, C, Altukhov, I, Alexeev, D, Aulchenko, Y, Amininejad, L, Bouma, G, Hoentjen, F, Lowenberg, M, Oldenburg, B, Pierik, Mj, vander Meulen-de Jong, Ae, van der Woude, Cj, Visschedijk, Mc, Lathrop, M, Hugot, Jp, Weersma, Rk, De Vos, M, Franchimont, D, Vermeire, S, Kubo, M, Louis, E, Georges, M, Abraham, C, Achkar, Jp, Ahmad, T, Ananthakrishnan, An, Andersen, V, Anderson, Ca, Andrews, Jm, Annese, V, Aumais, G, Baidoo, L, Baldassano, Rn, Bampton, Pa, Barclay, M, Barrett, Jc, Bayless, Tm, Bethge, J, Bitton, A, Boucher, G, Brand, S, Brandt, B, Brant, Sr, Buning, C, Chew, A, Cho, Jh, Cleynen, I, Cohain, A, Croft, A, Daly, Mj, D'Amato, M, Danese, S, De Jong, D, Denapiene, G, Denson, La, Devaney, Kl, Dewit, O, D'Inca, R, Dubinsky, M, Duerr, Rh, Edwards, C, Ellinghaus, D, Essers, J, Ferguson, Lr, Festen, Ea, Fleshner, P, Florin, T, Franke, A, Fransen, K, Gearry, R, Gieger, C, Glas, J, Goyette, P, Green, T, Griffiths, Am, Guthery, Sl, Hakonarson, H, Halfvarson, J, Hanigan, K, Haritunians, T, Hart, A, Hawkey, C, Hayward, Nk, Hedl, M, Henderson, P, Hu, Xh, Huang, Hl, Hui, Ky, Imielinski, M, Ippoliti, A, Jonaitis, L, Jostins, L, Karlsen, Th, Kennedy, Na, Khan, Ma, Kiudelis, G, Krishnaprasad, K, Kugathasan, S, Kupcinskas, L, Latiano, A, Laukens, D, Lawrance, Ic, Lee, Jc, Lees, Cw, Leja, M, Van Limbergen, J, Lionetti, P, Liu, Jz, Mahy, G, Mansfield, J, Massey, D, Mathew, Cg, Mcgovern, Dpb, Milgrom, R, Mitrovic, M, Montgomery, Gw, Mowat, C, Newman, W, Ng, A, Ng, Sc, Ng, Sme, Nikolaus, S, Ning, K, Nothen, M, Oikonomou, I, Palmieri, O, Parkes, M, Phillips, A, Ponsioen, Cy, Potocnik, U, Prescott, Nj, Proctor, Dd, Radford-Smith, G, Rahier, Jf, Raychaudhuri, S, Regueiro, M, Rieder, F, Rioux, Jd, Ripke, S, Roberts, R, Russell, Rk, Sanderson, Jd, Sans, M, Satsangi, J, Schadt, Ee, Schreiber, S, Schulte, D, Schumm, Lp, Scott, R, Seielstad, M, Sharma, Y, Silverberg, M, Simms, La, Skieceviciene, J, Spain, Sl, Steinhart, Ah, Stempak, Jm, Stronati, L, Sventoraityte, J, Targan, Sr, Taylor, Km, ter Velde, A, Torkvist, L, Tremelling, M, van Sommeren, S, Vasiliauskas, E, Verspaget, Hw, Walters, T, Wang, K, Wang, Mh, Wei, Z, Whiteman, D, Wijmenga, C, Wilson, Dc, Winkelmann, J, Xavier, Rj, Zhang, B, Zhang, Ck, Zhang, H, Zhang, W, Zhao, Hy, Zhao, Zz, Gastroenterology & Hepatology, UCL - SSS/IREC/GAEN - Pôle d'Hépato-gastro-entérologie, and UCL - (MGD) Service de gastro-entérologie

Subjects
Adult, Male, Multifactorial Inheritance, QUANTITATIVE TRAIT LOCUS, Genotype, SEQUENCING DATA, Quantitative Trait Loci, SUSCEPTIBILITY, Polymorphism, Single Nucleotide, Article, Cohort Studies, CODING VARIANTS, Crohn Disease, 80 and over, Journal Article, Medicine and Health Sciences, LOCUS, Humans, Genetic Predisposition to Disease, Polymorphism, GENOME-WIDE ASSOCIATION, Genetic Association Studies, Aged, Aged, 80 and over, Science & Technology, Female, Gene Expression Profiling, Inflammatory Bowel Diseases, Middle Aged, Sequence Analysis, DNA, COMPLEX TRAITS, Biology and Life Sciences, Single Nucleotide, DNA, CROHNS-DISEASE, Multidisciplinary Sciences, QUANTITATIVE TRAIT, RARE VARIANTS, Science & Technology - Other Topics, LOW-FREQUENCY, Sequence Analysis, INFLAMMATORY-BOWEL-DISEASE
Abstract

GWAS have identified >200 risk loci for Inflammatory Bowel Disease (IBD). The majority of disease associations are known to be driven by regulatory variants. To identify the putative causative genes that are perturbed by these variants, we generate a large transcriptome data set (nine disease-relevant cell types) and identify 23,650 cis-eQTL. We show that these are determined by ∼9720 regulatory modules, of which ∼3000 operate in multiple tissues and ∼970 on multiple genes. We identify regulatory modules that drive the disease association for 63 of the 200 risk loci, and show that these are enriched in multigenic modules. Based on these analyses, we resequence 45 of the corresponding 100 candidate genes in 6600 Crohn disease (CD) cases and 5500 controls, and show with burden tests that they include likely causative genes. Our analyses indicate that ≥10-fold larger sample sizes will be required to demonstrate the causality of individual genes using this approach., Most of the more than 200 known genetic risk loci for inflammatory bowel disease (IBD) reside in regulatory regions. Here, the authors provide eQTL datasets for six circulating immune cell types and ileal, colonic and rectal biopsies to map regulatory modules and identify potential causative genes for IBD.

Published
2018

39. Factors of Variation of Soil Chemical Properties in Metalliferous Ecosystems of Tenke-Fungurume, Katanga, Democratic Republic of the Congo

Author

Kaya Muyumba, D, Ilunga Wa Ilunga, E, Faucon, Michel-Pierre, Mahy, G, Liénard, A, Séleck, M, Ngongo Luhembwe, M, Colinet, G, Université de Lubumbashi, Agro-écologie, Hydrogéochimie, Milieux et Ressources (AGHYLE), UniLaSalle, and Université de Liège

Subjects
D. R. Congo, lcsh:S, Forestry, [SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study, 15. Life on land, cobalt, lcsh:Agriculture, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, metalliferous hills, Geography, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, copper, soil properties, vegetation units, Soil properties, General Agricultural and Biological Sciences, General Environmental Science
Abstract

Our study aimed at deepen our understanding of relationships between soil properties and vegetation distribution in metalliferous ecosystems of Tenke-Fungurume in the Democratic Republic of Congo. The first question concerned the differences and similarities between soils of the main vegetation units and four variation factors of soil properties were summarized by multivariate analysis. They were all linked to lithology and significantly contributed to explain the distribution of vegetation units. Our result suggest that the variation of soil properties which is observed within the various vegetation units (rocky steppe savanna, sward, and steppe savannas on slope or on Dembo) should partially be attributed to differences of geochemical composition of rocks between sites but the main source of variability is to be found inside each hill. The soil contamination in Cu and Co originates from rock weathering and besides site effect and topographic distribution of the rocks, the variability of soil properties within one vegetation unit may be due to variability of soil parent material and not only to erosion.The second question dealt with the changes of soil properties at small distances. Metric variation was studied from transects between adjacent vegetation units. Our results showed that the abrupt changes of vegetation units which were clearly identified on the field were all truly explained by the variations of one or more properties linked to lithology. The key point being the Cu bioavailability., Facteurs de variation des propriétés physico-chimiques des sols des écosystèmes métallifères de Tenke-Fungurume, Katanga, République Démocratique du CongoCette étude a pour objet les relations entre propriétés des sols et distribution des unités de végétation dans les écosystèmes métallifères de Tenke-Fungurume au Katanga en République Démocratique du Congo. La première question étudiée visait l’estimation des différences et similitudes entre sols des principales unités de végétation. La caractérisation des sols a permis d’identifier, par analyse multivariée, quatre facteurs de variation des propriétés physico-chimiques des sols qui sont tous liés à la lithologie. Nos résultats suggèrent que la variabilité observée entre unités de végétation (savane steppique enrochée, pelouse et savanes steppiques de pente ou de Dembo) est partiellement liée aux différences de composition géochimique des matériaux parentaux entre les sites mais également et principalement due à une variabilité importante du fond géochimique au sein de chaque unité de végétation. Les contaminations des sols en Cu et Co proviennent de l’altération des roches et la variabilité des teneurs mesurées au sein des unités de végétation peut aussi bien résulter de la variabilité des matériaux parentaux que des processus d’érosion.La deuxième question visait l’étude des transitions entre unités de végétation à l’échelle métrique. Les changements abrupts de végétation ont été clairement mis en parallèle avec des modifications des propriétés des sols, en lien avec la lithologie encore une fois. La clef de la distribution de ces unités est la disponibilité du cuivre.

Published
2019
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41. IBD risk loci are enriched in multigenic regulatory modules encompassing putative causative genes

Author

Momozawa, Y., Dmitrieva, J., Theatre, E., Deffontaine, V., Rahmouni, S., Charloteaux, B., Crins, F., Docampo, E., Elansary, M., Gori, A.S., Lecut, C., Mariman, R., Mni, M., Oury, C., Altukhov, I., Alexeev, D., Aulchenko, Y., Amininejad, L., Bouma, G., Hoentjen, F., Lowenberg, M., Oldenburg, B., Pierik, M.J., vander Meulen-de Jong, A.E., Woude, C.J. van der, Visschedijk, M.C., Lathrop, M., Hugot, J.P., Weersma, R.K., Vos, M. de, Franchimont, D., Vermeire, S., Kubo, M., Louis, E., Georges, M., Abraham, C., Achkar, J.P., Ahmad, T., Ananthakrishnan, A.N., Andersen, V., Anderson, C.A., Andrews, J.M., Annese, V., Aumais, G., Baidoo, L., Baldassano, R.N., Bampton, P.A., Barclay, M., Barrett, J.C., Bayless, T.M., Bethge, J., Bitton, A., Boucher, G., Brand, S., Brandt, B., Brant, S.R., Buning, C., Chew, A., Cho, J.H., Cleynen, I., Cohain, A., Croft, A., Daly, M.J., D'Amato, M., Danese, S., Jong, D. de, Denapiene, G., Denson, L.A., Devaney, K.L., Dewit, O., D'Inca, R., Dubinsky, M., Duerr, R.H., Edwards, C., Ellinghaus, D., Essers, J., Ferguson, L.R., Festen, E.A., Fleshner, P., Florin, T., Franke, A., Fransen, K., Gearry, R., Gieger, C., Glas, J., Goyette, P., Green, T., Griffiths, A.M., Guthery, S.L., Hakonarson, H., Halfvarson, J., Hanigan, K., Haritunians, T., Hart, A., Hawkey, C., Hayward, N.K., Hedl, M., Henderson, P., Hu, X.H., Huang, H.L., Hui, K.Y., Imielinski, M., Ippoliti, A., Jonaitis, L., Jostins, L., Karlsen, T.H., Kennedy, N.A., Khan, M.A., Kiudelis, G., Krishnaprasad, K., Kugathasan, S., Kupcinskas, L., Latiano, A., Laukens, D., Lawrance, I.C., Lee, J.C., Lees, C.W., Leja, M., Limbergen, J. van, Lionetti, P., Liu, J.Z., Mahy, G., Mansfield, J., Massey, D., Mathew, C.G., McGovern, D.P.B., Milgrom, R., Mitrovic, M., Montgomery, G.W., Mowat, C., Newman, W., Ng, A., Ng, S.C., Ng, S.M.E., Nikolaus, S., Ning, K., Nothen, M., Oikonomou, I., Palmieri, O., Parkes, M., Phillips, A., Ponsioen, C.Y., Potocnik, U., Prescott, N.J., Proctor, D.D., Radford-Smith, G., Rahier, J.F., Raychaudhuri, S., Regueiro, M., Rieder, F., Rioux, J.D., Ripke, S., Roberts, R., Russell, R.K., Sanderson, J.D., Sans, M., Satsangi, J., Schadt, E.E., Schreiber, S., Schulte, D., Schumm, L.P., Scott, R., Seielstad, M., Sharma, Y., Silverberg, M.S., Simms, L.A., Skieceviciene, J., Spain, S.L., Steinhart, A.H., Stempak, J.M., Stronati, L., Sventoraityte, J., Targan, S.R., Taylor, K.M., Velde, A. ter, Torkvist, L., Tremelling, M., Sommeren, S. van, Vasiliauskas, E., Verspaget, H.W., Walters, T., Wang, K., Wang, M.H., Wei, Z., Whiteman, D., Wijmenga, C., Wilson, D.C., Winkelmann, J., Xavier, R.J., Zhang, B., Zhang, C.K., Zhang, H., Zhang, W., Zhao, H.Y., Zhao, Z.Z., and Int IBD Genetics Consortium

Published
2018

44. P571 Vedolizumab (VDZ) real-world outcomes in ulcerative colitis (UC)

Author

Pulusu, S S R, primary, Srinivasan, A, additional, Krishnaprasad, K, additional, Cheng, D, additional, Mogilevski, T, additional, Flanagan, E, additional, Keung, C, additional, Wu, C, additional, Prosser, R, additional, Sawyer, E, additional, Rizvi, Q -U -A, additional, Su, H, additional, Leung, W -K, additional, Edmundson, A, additional, Cooke, S, additional, Mahy, G, additional, Thin, L, additional, Radford-Smith, G, additional, Sparrow, M, additional, Andrews, J M, additional, Connor, S, additional, Bampton, P, additional, Ghaly, S, additional, Van Langenberg, D, additional, Bell, S, additional, De Cruz, P, additional, Begun, J, additional, Ng, S, additional, Travis, S, additional, and Lawrance, I, additional

Published
2018
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46. Inherited determinants of Crohn's disease and ulcerative colitis phenotypes:a genetic association study

Author

Cleynen, Isabelle, Boucher, Gabrielle, Jostins, Luke, Schumm, L. Philip, Zeissig, Sebastian, Ahmad, Tariq, Andersen, Vibeke, Andrews, Jane M., Annese, Vito, Brand, Stephan, Brant, Steven R., Cho, Judy H., Daly, Mark J., Dubinsky, Marla, Duerr, Richard H., Ferguson, Lynnette R., Franke, Andre, Gearry, Richard B., Goyette, Philippe, Hakonarson, Hakon, Halfvarson, Jonas, Hov, Johannes R., Huang, Hailang, Kennedy, Nicholas A., Kupcinskas, Limas, Lawrance, Ian C., Lee, James C., Satsangi, Jack, Schreiber, Stephan, Théâtre, Emilie, Van Der Meulen De Jong, Andrea E, Weersma, Rinse K., Wilson, David C., Parkes, Miles, Vermeire, Severine, Rioux, John D., Mansfield, John, Silverberg, Mark S., Radford Smith, Graham, Mcgovern, Dermot P. B., Barrett, Jeffrey C., Lees, Charlie W, Abraham, C, Achkar, Jp, Ahmad, T, Amininejad, L, Ananthakrishnan, An, Andersen, V, Anderson, Ca, Andrews, Jm, Annese, V, Aumais, G, Baidoo, L, Baldassano, Rn, Bampton, Pa, Barclay, M, Barrett, Jc, Bayless, Tm, Bethge, J, Bis, Jc, Bitton, A, Boucher, G, Brand, S, Brandt, B, Brant, Sr, Büning, C, Chew, A, Cho, Jh, Cleynen, I, Cohain, A, Croft, A, Daly, Mj, D'Amato, M, Danese, S, De Jong, D, De Vos, M, Denapiene, G, Denson, La, Devaney, K, Dewit, O, D'Inca, R, Dubinsky, M, Duerr, Rh, Edwards, C, Ellinghaus, D, Essers, J, Ferguson, Lr, Festen, Ea, Fleshner, P, Florin, T, Franchimont, D, Franke, A, Fransen, K, Gearry, R, Georges, M, Gieger, C, Glas, J, Goyette, P, Green, T, Griffiths, Am, Guthery, Sl, Hakonarson, H, Halfvarson, J, Hanigan, K, Haritunians, T, Hart, A, Hawkey, C, Hayward, Nk, Hedl, M, Henderson, P, Hu, X, Huang, H, Hui, Ky, Imielinski, M, Ippoliti, A, Jonaitis, L, Jostins, L, Karlsen, Th, Kennedy, Na, Khan, Ma, Kiudelis, G, Krishnaprasad, K, Kugathasan, S, Kupcinskas, L, Latiano, A, Laukens, D, Lawrance, Ic, Lee, Jc, Lees, Cw, Leja, M, Van Limbergen, J, Lionetti, P, Liu, Jz, Louis, E, Mahy, G, Mansfield, J, Massey, D, Mathew, Cg, Mcgovern, Dp, Milgrom, R, Mitrovic, M, Montgomery, Gw, Mowat, C, Newman, W, Ng, A, Ng, Sc, Ng, Sm, Nikolaus, S, Ning, K, Nöthen, M, Oikonomou, I, Palmieri, O, Parkes, M, Phillips, A, Ponsioen, Cy, Potocnik, U, Prescott, Nj, Proctor, Dd, Radford Smith, G, Rahier, Jf, Raychaudhuri, S, Regueiro, M, Rieder, F, Rioux, Jd, Ripke, S, Roberts, R, Russell, Rk, Sanderson, Jd, Sans, M, Satsangi, J, Schadt, Ee, Schreiber, S, Schumm, Lp, Scott, R, Seielstad, M, Sharma, Y, Silverberg, Ms, Simms, La, Skieceviciene, J, Spain, Sl, Steinhart, A, Stempak, Jm, Stronati, Laura, Sventoraityte, J, Targan, Sr, Taylor, Km, ter Velde, A, Theatre, E, Torkvist, L, Tremelling, M, van der Meulen, A, van Sommeren, S, Vasiliauskas, E, Vermeire, S, Verspaget, Hw, Walters, T, Wang, K, Wang, Mh, Weersma, Rk, Wei, Z, Whiteman, D, Wijmenga, C, Wilson, Dc, Winkelmann, J, Xavier, Rj, Zeissig, S, Zhang, B, Zhang, Ck, Zhang, H, Zhang, W, Zhao, H, Zhao, Zz, UCL - SSS/IREC/GAEN - Pôle d'Hépato-gastro-entérologie, UCL - (MGD) Service de gastro-entérologie, and Groningen Institute for Gastro Intestinal Genetics and Immunology (3GI)

Subjects
Male, 0301 basic medicine, CLINICAL-COURSE, Nod2 Signaling Adaptor Protein, Disease, SUSCEPTIBILITY, Inflammatory bowel disease, Major Histocompatibility Complex, 0302 clinical medicine, Crohn Disease, Maintenance therapy, NOD2, Medicine and Health Sciences, POPULATION, Immunoassay, RISK, Medicine(all), education.field_of_study, Crohn's disease, Hepatocyte Growth Factor, Medicine (all), INDUCTION, Articles, General Medicine, PRIMARY SCLEROSING CHOLANGITIS, Ulcerative colitis, 3. Good health, Phenotype, Female, 030211 gastroenterology & hepatology, Adult, medicine.medical_specialty, MAINTENANCE THERAPY, Genotype, Population, Polymorphism, Single Nucleotide, Risk Assessment, CLASSIFICATION, Primary sclerosing cholangitis, Young Adult, 03 medical and health sciences, inflammatory bowel disease, Proto-Oncogene Proteins, Internal medicine, medicine, Humans, Genetic Predisposition to Disease, education, Alleles, Genetic Association Studies, business.industry, medicine.disease, digestive system diseases, 030104 developmental biology, Immunology, Colitis, Ulcerative, business, FOLLOW-UP, HLA-DRB1 Chains, INFLAMMATORY-BOWEL-DISEASE
Abstract

Background: Crohn's disease and ulcerative colitis are the two major forms of inflammatory bowel disease; treatment strategies have historically been determined by this binary categorisation. Genetic studies have identified 163 susceptibility loci for inflammatory bowel disease, mostly shared between Crohn's disease and ulcerative colitis. We undertook the largest genotype association study, to date, in widely used clinical subphenotypes of inflammatory bowel disease with the goal of further understanding the biological relations between diseases.Methods: This study included patients from 49 centres in 16 countries in Europe, North America, and Australasia. We applied the Montreal classification system of inflammatory bowel disease subphenotypes to 34 819 patients (19 713 with Crohn's disease, 14 683 with ulcerative colitis) genotyped on the Immunochip array. We tested for genotype–phenotype associations across 156 154 genetic variants. We generated genetic risk scores by combining information from all known inflammatory bowel disease associations to summarise the total load of genetic risk for a particular phenotype. We used these risk scores to test the hypothesis that colonic Crohn's disease, ileal Crohn's disease, and ulcerative colitis are all genetically distinct from each other, and to attempt to identify patients with a mismatch between clinical diagnosis and genetic risk profile.Findings: After quality control, the primary analysis included 29 838 patients (16 902 with Crohn's disease, 12 597 with ulcerative colitis). Three loci (NOD2, MHC, and MST1 3p21) were associated with subphenotypes of inflammatory bowel disease, mainly disease location (essentially fixed over time; median follow-up of 10·5 years). Little or no genetic association with disease behaviour (which changed dramatically over time) remained after conditioning on disease location and age at onset. The genetic risk score representing all known risk alleles for inflammatory bowel disease showed strong association with disease subphenotype (p=1·65 × 10−78), even after exclusion of NOD2, MHC, and 3p21 (p=9·23 × 10−18). Predictive models based on the genetic risk score strongly distinguished colonic from ileal Crohn's disease. Our genetic risk score could also identify a small number of patients with discrepant genetic risk profiles who were significantly more likely to have a revised diagnosis after follow-up (p=6·8 × 10−4).Interpretation: Our data support a continuum of disorders within inflammatory bowel disease, much better explained by three groups (ileal Crohn's disease, colonic Crohn's disease, and ulcerative colitis) than by Crohn's disease and ulcerative colitis as currently defined. Disease location is an intrinsic aspect of a patient's disease, in part genetically determined, and the major driver to changes in disease behaviour over time.Funding: International Inflammatory Bowel Disease Genetics Consortium members funding sources (see Acknowledgments for full list).

Published
2016

47. Revue bibliographique sur la restauration des pelouses calcicoles en Europe : contraintes rencontrées et solutions proposées

Author

Piqueray, J. and Mahy G.

Subjects
lcsh:GE1-350, Restoration ecology, calcareous grasslands, lcsh:Biotechnology, lcsh:TP248.13-248.65, biotic/abiotic conditions, restoration techniques, lcsh:Environmental sciences, plant communities
Abstract

The restoration of calcareous grasslands in Europe: a review of constraints and solutions. Calcareous grasslands that are considered as biodiversity hotspots in Europe, have suffered an important decline during the last century. In this context, restoration of suitable habitats has been promoted as a conservation strategy. Restoration consists in the recreation of favorable abiotic and biotic conditions that permit the recolonization by typical species. Depending on the degradations, several constraints can be encountered during restoration, such as soil enrichment, the presence of competitive species, or harsh conditions for plant growth. In order to overcome these constraints, scientists have proposed techniques that were demonstrated to be more or less efficient. In this article, the different constraints that can occur while restoring calcareous grasslands are described as well as the techniques proposed in the scientific literature. We also describe restoration objectives specific to calcareous grasslands, taking the history of these habitats into account and considering global change issue. Different parameters can be considered to value restoration success. Here again, an analysis of the scientific literature is needed in order to best assess restoration monitoring.

Published
2010

48. Evolution des traits d'histoire de vie lors des invasions végétales

Author

Monty A. and Mahy G.

Subjects
lcsh:GE1-350, lcsh:Biotechnology, fungi, food and beverages, introduced range, biological invasion, natural selection, native range, founder effect, lcsh:TP248.13-248.65, genetic drift, common garden, Life history, EICA hypothesis, lcsh:Environmental sciences
Abstract

Life history trait evolution during plant invasion. Despite the problems they cause, plant invasions can be seen as opportunities for the study of rapid evolution. In this paper are presented the main evolutionary changes in life history that can occur during the three main plant invasion phases: introduction, naturalization and expansion in the new range. The study of those evolutionary changes is traditionally split in the comparison between native and introduced populations and the study of life history differentiation within the invaded area.

Published
2009

49. La quinoa en Bolivie : une culture ancestrale devenue culture de rente

Author

Winkel T., Del Castillo C., and Mahy G.

Subjects
Agrobiodiversity, lcsh:GE1-350, Bolivia, genetic resources, frost resistance, drought resistance, lcsh:Biotechnology, lcsh:TP248.13-248.65, Chenopodium quinoa, lcsh:Environmental sciences
Abstract

Quinoa in Bolivia: an ancestral crop changed to a cash crop with " organic fair-trade " labeling. This paper presents a review of the litterature on the physiology and diversity of quinoa (Chenopodium quinoa Willd.). Since about 15 years, this Andean crop experiences a great commercial success in the organic and fair-trade food networks. Selected and cultivated for thousands of years in the Andean highlands, quinoa shows a remarkable tolerance to environmental stresses, particularly to drought and cold. The present knowledges on quinoa physiology, though fragmentary, show a high cold resistance of the plants, and the capacity to recover high photosynthetic activity after drought. Under field conditions, the genetic diversity in local landraces and the crop practices also contribute notably to the adaptation of quinoa to climatic hazards.

Published
2008

50. Implications des relations sol-plante en ingénierie écologique des habitats et sols métallifères dégradés: le cas des habitats riches en cuivre du Katanga (République Démocratique du Congo)

Author

Faucon, Michel-Pierre, Ilunga, E, Lange, Bastien, Boisson, S, Seleck, M, Le Stradic, S, Shutcha, M, Grison, C, Pourret, Olivier, Meerts, P, Mahy, G, Pourret, Olivier, and UniLaSalle

Subjects
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.GC] Sciences of the Universe [physics]/Earth Sciences/Geochemistry
Abstract

International audience; La restauration écologique des habitats dégradés et des sols nus riches en métaux lourds créés par l'activité minière est devenue aujourd'hui un enjeu environnemental majeur pour réduire l'érosion de la biodiversité et la dégradation des paysages, des sols et de l'eau. Les études de restauration écologique basées sur l'identification des espèces sans faire référence aux traits fonctionnels des plantes sont limitées au réservoir régional des espèces et rendent difficile les interprétations et les applications dans des contextes écologiques variés. En comparant les traits fonctionnels des plantes entre l'habitat métallifère non dégradé et un gradient de succession d'habitats secondaires, il est possible de définir des traits liés à la capacité de colonisation des sols nus riches en métaux lourds. Cette première tentative d'analyse des traits sur les habitats riches en métaux lourds permet ainsi d'identifier les traits candidats pour la phytoremediation. Un des futurs challenges est de créer de nouveaux écosystèmes fonctionnels sur les sols nus contaminés par les métaux lourds en

Published
2015

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