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See detailDiversity and aboveground biomass in three tropical forest types in the Dja Biosphere Reserve, Cameroon
Djuikouo, Marie Noël Kamdem; Doucet, Jean-Louis ULg; Nguembou, Charlemagne K. et al

in African Journal of Ecology (2010), 48

We present tree community diversity, species composition, basal area and aboveground biomass of three forest types in the Dja Biosphere Reserve, in South-East Cameroon, part of the contiguous tropical ... [more ▼]

We present tree community diversity, species composition, basal area and aboveground biomass of three forest types in the Dja Biosphere Reserve, in South-East Cameroon, part of the contiguous tropical forest of the Congo Basin. A total of fourteen, 1 ha, plots were established in heterogeneous terra firme forests (TFF), Gilbertiodendron dewevrei forests (GDF) and periodically flooded forests (PFF). A total of 281 tree species with diameter ‡10 cm were recorded. The Shannon diversity index was significantly higher in TFF (5.7 ± 0.28) and PFF (5.6 ± 0.23) than in GDF (2.29 ± 0.48) (ANOVA, F2,11 = 139.75, P < 0.001). While tree density did not differ between forest types (F2,11 = 3.50, P = 0.06), basal area differed significantly (F2,11 = 7.38, P = 0.009), as did aboveground biomass (F2,11 = 17.95, P < 0.001). Mean AGB values were respectively, 596.1 ± 62.24, 401.67 ± 58.06 and 383.14 ± 61.91 Mg ha)1 in GDF, TFF and PFF. Variation in the abundance of trees with large diameter was the main reason for these differences. Few dominant species made the greatest contribution to the AGB. G. dewevrei, accounted for 83% of AGB in GDF, Penthaclethra macrophylla for 9.9% in TFF and Uapaca heudolotii for 10.6% in PFF. The importance of preserving G. dewevrei forest in the context of ‘Reducing Emissions from Deforestation and forest Degradation’ (REDD) policies is discussed. [less ▲]

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See detailDiversity and breeding sites of mosquitoes (Diptera, Culicidae) potentially vectors of arboviruses in Belgian equestrian farms
Boukraa, Slimane ULg; De la Grandière de Noronha Cotta, Maria Ana ULg; Bawin, Thomas ULg et al

Poster (2012, October 08)

This study aims to determine the potential importance of the livestock farms, especially equestrian, to welcome and favor the proliferation of certain species of mosquito responsible for transmission of ... [more ▼]

This study aims to determine the potential importance of the livestock farms, especially equestrian, to welcome and favor the proliferation of certain species of mosquito responsible for transmission of arboviruses. The study of biodiversity of Culicidae in the horse farms in Belgium is carried out on species sampled at 64 biotopes in six stations study. Five surveys were realized during 2011 (June, July, August and October) and one in 2012 (June). The morphotaxonomic and molecular study of mosquitoes collected showed the presence of ten species: Culisata annulata Schrank, 1776; Anopheles claviger s.s. Meigen, 1804; An. maculipennis s.s. Meigen, 1818; An. messae Falleroni, 1926; Culex pipiens molestus Forskal, 1775; Cx. pipiens pipiens Linné, 1758; Cx. torrentium Martini, 1925; Cx. hortensis hortensis Ficalbi, 1889; Cx. territans Walker, 1856 and Coquillettidia richardii Ficalbi, 1889. Among the 24893 individuals examined in 2011, Cx. pipiens sl and Cx. torrentium represent 68.00% and 22.38% respectively of total harvest. These last species with Cs. annulata, are dominants and ubiquitous in all the horse farms visited. The species of the genus Anopheles have strong ecological requirements and are therefore associated with some special habitats; other species however have a strong ability to adapt and therefore attend a wide variety of biotopes (Cx. pipiens, Cx. torrentium and Cs. annulata). At the horse farms, water troughs and ponds are the most favorable habitats for larval development of Culicidae. The species potentially vectors of arboviruses that can cause problems in epidemiological equestrian farms are Cx. pipiens sl, Cx. torrentium and Cs. annulata. [less ▲]

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See detailDiversity and carbon storage across the tropical forest biome
Sullivan, Martin J.P.; Talbot, Joey; Lewis, Simon L. et al

in Scientific Reports (2017), 7(39102),

Tropical forests are global centres of biodiversity and carbon storage. Many tropical countries aspire to protect forest to fulfil biodiversity and climate mitigation policy targets, but the conservation ... [more ▼]

Tropical forests are global centres of biodiversity and carbon storage. Many tropical countries aspire to protect forest to fulfil biodiversity and climate mitigation policy targets, but the conservation strategies needed to achieve these two functions depend critically on the tropical forest tree diversity-carbon storage relationship. Assessing this relationship is challenging due to the scarcity of inventories where carbon stocks in aboveground biomass and species identifications have been simultaneously and robustly quantified. Here, we compile a unique pan-Tropical dataset of 360 plots located in structurally intact old-growth closed-canopy forest, surveyed using standardised methods, allowing a multi-scale evaluation of diversity-carbon relationships in tropical forests. Diversity-carbon relationships among all plots at 1 ha scale across the tropics are absent, and within continents are either weak (Asia) or absent (Amazonia, Africa). A weak positive relationship is detectable within 1 ha plots, indicating that diversity effects in tropical forests may be scale dependent. The absence of clear diversity-carbon relationships at scales relevant to conservation planning means that carbon-centred conservation strategies will inevitably miss many high diversity ecosystems. As tropical forests can have any combination of tree diversity and carbon stocks both require explicit consideration when optimising policies to manage tropical carbon and biodiversity. [less ▲]

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See detailDiversity and Cohesion in Europe : Towards a Multicultural EU Citizenship
Martiniello, Marco ULg

Scientific conference (2005, April 12)

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See detailDiversity and complexity in the acoustic behaviour of Dacyllus flavicaudus (Pomacentridae)
Parmentier, Eric ULg; Kever, Loïc ULg; Casadevall, Margardia et al

in Marine Biology (2010), 157(10), 2317-2327

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See detailDiversity and complexity of Early Eukaryotic cells
Javaux, Emmanuelle ULg; Knoll, A. H.; Walter, M.

Conference (2003)

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See detailDiversity and correlation of Givetian records in southern Belgium
Pas, Damien ULg; Poulain, Geoffrey; Labaye, Corentin et al

in Berichte des Institutes für Erdwissenschaften der Karl-Franzens-Universität Graz (2014, August), 19

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See detailDiversity and disparity of the Mesozoic plant fossil record
Cascales - Miñana, Borja ULg; Sender, Luis Miguel; Villanueva-Amadoz, Uxue et al

Conference (2011, September)

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See detailDiversity and distribution of microorganisms in microbial mats of Antarctic lakes
Lara, Yannick ULg; Durieu, Benoit ULg; Stelmach Pessi, Igor ULg et al

Conference (2016, August)

The BelSPO project CCAMBIO aims to study the biogeographical distribution of microorganisms in lacustrine microbial mats using a combination of techniques including microscopic observations, strain ... [more ▼]

The BelSPO project CCAMBIO aims to study the biogeographical distribution of microorganisms in lacustrine microbial mats using a combination of techniques including microscopic observations, strain isolation and genetic characterisation, and molecular diversity assessments using Next Generation Sequencing of environmental DNA. The samples were collected in different Antarctic and sub-Antarctic biogeographical regions. Preliminary multivariate analysis of >130 samples revealed strong bioregionalisation patterns in microbial eukaryotes, which are in agreement with the classical subdivision of the Antarctic Realm into Maritime Antarctica, Continental Antarctica and the Sub-Antarctic Islands generally observed in plants and animals. The biogeographic structuring was less strong between the continent and Maritime Antarctica in prokaryotes suggesting more regular dispersal events between these two regions. The Sub-Antarctic assemblages harboured more complex foodwebs, with arthropods, nematods, rotifers, flatworms and annelids as main metazoan groups. Lakes on the continent, however, were characterised by fewer metazoan groups and a greater importance of microbial herbivores and secondary consumers, including a relative high diversity of ciliates and tardigrades. In a first analysis of microbial mats from five Antarctic lakes and an aquatic biofilm from the Sub-Antarctic, the majority of the cyanobacterial OTUs retrieved were related to filamentous taxa such as Leptolyngbya and Phormidium, which are common genera in Antarctic lacustrine microbial mats. However, other phylotypes related to different taxa such as Geitlerinema, Pseudanabaena, Synechococcus, Chamaesiphon, Calothrix and Coleodesmium were also found. Results revealed a much higher diversity than what had been reported using traditional methods and also highlighted remarkable differences between the cyanobacterial communities of the studied lakes. In the coming months, the molecular diversity data will be deposited into the “Microbial Antarctic Resource System (MARS)” presently developed into the webportal ‘biodiversity.aq’. Better knowledge of the diversity and distribution of microorganisms will contribute to a better assessment of their resilience and local/regional responses to global change [less ▲]

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See detailDiversity and ecology survey of mosquitoes potential vectors in Belgian equestrian farms: A threat prevention of mosquito-borne equine arboviruses
Boukraa, Slimane ULg; de la Grandière, Maria Ana ULg; Bawin, Thomas ULg et al

in Preventive Veterinary Medicine (2016), 124

Emergence of West Nile Virus was recently recorded in several European countries, which can lead to severe health problems in horse populations. Europe is also at risk of introduction of mosquito-borne ... [more ▼]

Emergence of West Nile Virus was recently recorded in several European countries, which can lead to severe health problems in horse populations. Europe is also at risk of introduction of mosquito-borne equine alphavirus from Americas. Prevention of these arboviruses requires a clear understanding of transmission cycles, especially their vectors. To characterize mosquito fauna, their ecology and identify potential vectors of equine arboviruses in Belgium, entomological surveys of six equestrian farms located in the Wolloon Region were conducted during 2011–2012. The harvest of mosquitoes was based on larval sampling (272 samples from 111 breeding sites) and monthly adults trapping (CO2-baited traps, Mosquito Magnet Liberty Plus). Among 51,493 larvae and 319 adult mosquitoes collected, morphological identification showed the presence of 11 species: Anopheles claviger (Meigen), An. maculipennis s.l. (Meigen), An. plumbeus (Stephens), Culex hortensis (Ficalbi), Cx. territans (Walker), Cx. pipiens s.l. L., Cx. torrentium (Martini), Coquillettidia richiardii (Ficalbi), Culiseta annulata (Schrank), Aedes cantans (Meigen), Ae. geniculatus (Olivier). Molecular identification of Cx. pipiens species complex allowed the detection of three molecular forms, Pipiens (92.3%), Molestus (4.6%) and Hybrid (3.1%). Larvae of Cx. pipiens sl and Cx. torrentium were omnipresent and the most abundant species. Water troughs, ponds and slurry (liquid manure) were the most favorable breeding sites of mosquito larvae. Based upon behavior and ecology of the identified mosquito species, Studied Belgian equestrian farms seem to provide a suitable environment and breeding sites for the proliferation of potential vectors of arboviruses and those being a real nuisance problem for horses and neighboring inhabitants. [less ▲]

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See detailDiversity and endemism of Murinae rodents in Thai limestone karsts
Latinne, Alice ULg; Waengsothorn, Surachit; Rojanadilok, Prateep et al

in Systematics and Biodiversity (2013), 11(3), 323-344

This study aims to investigate the species diversity of rodents living in karst ecosystems of Thailand. A survey has been conducted throughout Thailand, 122 karsts sampled and 477 Murinae rodents live ... [more ▼]

This study aims to investigate the species diversity of rodents living in karst ecosystems of Thailand. A survey has been conducted throughout Thailand, 122 karsts sampled and 477 Murinae rodents live-trapped. Phylogenetic reconstructions were carried out using two mitochondrial markers (cytb, COI). A sequence-based species delimitation method completed by the analysis of the level of genetic divergence was then applied to define species boundaries within our dataset. The phylogenetic position of Niviventer hinpoon was also investigated and sequences obtained from the holotype specimen of this species were used to reliably identify samples of N. hinpoon. A total of 12 described Murinae species, corresponding to 17 deeply divergent genetic lineages, were encountered in limestone karsts of Thailand. Our study revealed an important genetic diversity within the traditionally recognized species Maxomys surifer (four highly divergent genetic lineages), Leopoldamys neilli (two highly divergent genetic lineages) and Berylmys bowersi (two highly divergent genetic lineages). These species could be considered as species complex and require further taxonomic work. This study also provides valuable information on the distribution of the two rodent species endemic to limestone karsts of Thailand, L. neilli and N. hinpoon. Leopoldamys neilli was the most abundant species encountered in Thai karsts during our survey. However, L. neilli specimens from western Thailand are genetically highly divergent from the remaining populations of L. neilli and could represent a separate species. Niviventer hinpoon, phylogenetically closely related to N. fulvescens, is much rarer and its distribution limited to central Thailand. Most of the other captured species are typically associated with forest ecosystems. This study suggests that limestone karsts play a key role in the preservation of the rodent species endemic to such habitat, but they would also provide refuges for the forest-dwelling Murinae rodents in deforested regions. [less ▲]

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See detailDiversity and endemism of Murinae rodents in Thai limestone karsts: a genetic approach
Latinne, Alice ULg

Doctoral thesis (2012)

Limestone karsts are characterized by an important species richness and high levels of endemic species of plants, vertebrates and invertebrates adapted to this extreme environment. However, in Southeast ... [more ▼]

Limestone karsts are characterized by an important species richness and high levels of endemic species of plants, vertebrates and invertebrates adapted to this extreme environment. However, in Southeast Asia, karst ecosystems suffer from a considerable lack of scientific data and remain widely unknown despite their high biological importance. Combining field investigations with phylogeographic and phylogenetic analyses based on several kinds of molecular markers, this thesis aims at exploring the diversity and endemism of Murinae rodents in limestone karsts of Thailand. Thai limestone karsts host two endemic Murinae rodent species, Leopoldamys neilli and Niviventer hinpoon. This thesis reveals that L. neilli is more largely distributed in Thailand than indicated by previous records available in the literature. The species has been recorded in numerous limestone karsts of Thailand with the exception of its peninsular area. L. neilli has also been discovered in central Laos. Moreover our niche modeling study indicates that large tracts of suitable habitat for this species may also occur in several regions of Indochina. L. neilli populations are highly fragmented and a deep genealogical divergence among its lineages is observed. Both mitochondrial and nuclear markers support a large-scale population structure of four main groups (west, centre, north and northeast) and a strong finer structure within each of these groups. These results indicate that L. neilli populations are isolated on karsts such as on islands and that migrations among them are reduced. Our findings also suggest that the current phylogeographic pattern of this species results from the fragmentation of a widespread ancestral population and that vicariance has played a significant role in the evolutionary history of L. neilli. These deep vicariant events that occurred during Plio-Pleistocene are related to the formation of the Central Plain of Thailand. Moreover, the western populations of L. neilli are genetically and morphologically highly divergent from the other populations and could represent a separate species. This strong phylogeographic pattern is not observed for other Murinae species with lower levels of ecological specialization such as Leopoldamys edwardsi and Rattus tanezumi. Finally, this thesis provides preliminary information about the diet of L. neilli and indicates that plants of the Solanaceae family constitute an important part of its diet. The phylogeographic structure of N. hinpoon is not similar to the one of L. neilli. In contrast to L. neilli, N. hinpoon is confined to central Thailand and mitochondrial markers used in this study indicated that this species is genetically homogenous and characterized by a single mitochondrial lineage. Valuable data to refine the conservation status of L. neilli and N. hinpoon, two species currently listed as Data Deficient on the IUCN Red List have been gathered during this study. Three main threats to the long-term subsistence of L. neilli have been identified: (1) the high fragmentation of its population, (2) the large-scale destruction of limestone karsts in Southeast Asia, and (3) the intense trapping of this species for human consumption in northeastern Thailand. Therefore we propose to consider L. neilli as “Near threatened” on the IUCN Red List. However, if the western lineage of L. neilli represents a separate species, it should be listed as “Vulnerable”. Due to its small distribution range and the high threats that its habitat is facing in central Thailand, N. hinpoon would also be qualified as “Vulnerable” on the IUCN Red List. In addition to karst endemic species, this thesis reveals that Thai limestone karsts host high levels of Murinae rodent diversity. A sequence-based species delimitation method completed by the analysis of the level of genetic divergence was used to define species boundaries within our rodent samples collected in limestone karsts. A total of 12 described Murinae species, corresponding to 17 putative species based on our genetic criteria, were encountered in limestone karsts of Thailand. Most of these species are associated to forest ecosystems. Therefore this study suggests that limestone karsts could play a key role in the preservation of the rodent biodiversity by providing refuges for the forest-dwelling Murinae rodents in deforested regions. An important cryptic diversity has been detected within the traditionally recognized species Maxomys surifer and Berylmys bowersi. They could be considered as species complex and require further taxonomic work. The potential distribution of Leopoldamys edwardsi and Leopoldamys sabanus, two species also distributed in Thailand, has been investigated using niche modeling techniques. The predicted distribution ranges of these two species suggest a clear geographical separation between them, with the potential distribution of L. edwardsi being limited to the northern part of Indochina while L. sabanus is mainly distributed in the Sundaic region. Our findings also suggest that these two species could have survived in large areas of Southeast Asia during Quaternary ice ages without large scale extinction and that no drastic modification of the distribution of these species will occur in the future due to climate changes. In conclusion, using various genetic approaches, this work gains important insights into the Murinae rodent diversity of Thai limestone karsts and represents the first detailed study of karst endemic rodent species in Southeast Asia. [less ▲]

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See detailThe diversity and evolution of late-Archean granitoids: Evidence for the onset of “modern-style” plate tectonics between 3.0 and 2.5 Ga
Laurent, Oscar ULg; Martin, Hervé; Moyen, Jean-François et al

in Lithos (2014), 205

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See detailDiversity and evolution of transposable elements in the Arabidopsis lyrata and A. halleri genomes
Caron, Thibault; Legrand, Sylvain; Schvartzman Echenique, Maria Sol ULg et al

Conference (2016, July 07)

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See detailDIVERSITY AND HOST SPECIFICITY OF AZOLLA CYANOBIONTS
Papaefthimiou, Dimitra; Van Hove, Charles; Lejeune, André et al

in Journal of Phycology (2008), 44

A unique, hereditary symbiosis exists between the water fern Azolla and cyanobacteria that reside within a cavity in the dorsal leaf-lobe of the plant. This association has been studied extensively, and ... [more ▼]

A unique, hereditary symbiosis exists between the water fern Azolla and cyanobacteria that reside within a cavity in the dorsal leaf-lobe of the plant. This association has been studied extensively, and questions have frequently been raised regarding the number and diversity of cyanobionts (cyanobacterial symbionts) among the different Azolla strains and species. In this work, denaturating gradient gel electrophoresis (DGGE) and a clone library based on the 16S rRNA gene were used to study the genetic diversity and host specificity of the cyanobionts in 35 Azolla strains covering a wide taxonomic and geographic range. DNA was extracted directly from the cyanobacterial packets, isolated after enzymatic digestion of the Azolla leaves. Our results indicated the existence of different cyanobiont strains among Azolla species, and diversity within a single Azolla species, independent of the geographic origin of the host. Furthermore, the cyanobiont exhibited host-species specificity and showed most divergence between the two sections of genus Azolla, Azolla and Rhizosperma. These findings are in agreement with the recent redefinition of the taxon Azolla cristata within the section Azolla. With regard to the taxonomic status of the cyanobiont, the genus Anabaena of the Nostocaceae family was identified as the closest relative by this work. [less ▲]

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See detailDiversity and paleobiology of Proterozoic organic-walled microfossils from Arctic Canada
Loron, Corentin ULg; Javaux, Emmanuelle ULg

in Steemans, Philippe; Gerrienne, Philippe (Eds.) Miscellanea palaeontologica 2016 (2016, December)

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See detailDiversity and pathogenicity of Pseudomonas cichorii isolates causing midrib rot on lettuce
Pauwelyn, E.; Ongena, Marc ULg; Cottyn, B. et al

Conference (2010)

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See detailThe diversity and tolerance to osmotic stress of East Antarctic filamentous Cyanobacteria
Obbels, Dagmar; Verleyen, Elie; Tytgat, Bjorn et al

Poster (2013, July)

Filamentous cyanobacteria are keystone species in Antarctic lake ecosystems; they are the basis of the simple foodwebs, play a crucial role in biogeochemical cycling and form the structure of benthic ... [more ▼]

Filamentous cyanobacteria are keystone species in Antarctic lake ecosystems; they are the basis of the simple foodwebs, play a crucial role in biogeochemical cycling and form the structure of benthic microbial mats which act as habitats for other prokaryotic and (micro-eukaryotic biota. Despite this, little is known about their diversity, adaptation and survival strategies in the extreme Antarctic conditions. We studied the uncultivated prokaryotic diversity using a 454 metagenomic analysis at the 16S rRNA level (V1-V3 region) in Continental Antarctic lakes situated along a conductivity gradient (0.014-142.02 mS/cm). The quality and length of the amplicons was analyzed with a custom-made Mothur pipeline and the resulting sequences were mapped against the Greengenes database, which includes CyanoDB. Almost 27% of the sequences could be assigned to the phylum of the cyanobacteria. The most abundant cyanobacteria in the dataset belonged to the genera Microcoleus, Leptolyngbya, Pseudanabaena, Nodularia and Phormidum. Some 16S rRNA types (at the 97% similarity level), such as sequences related to Leptolynbya antarctica, were present in both freshwater and hypersaline lakes. In order to further investigate this distribution, we isolated filaments of Leptolyngbya from seven lakes with conductivities ranging between 26.8 mS/cm and 0.038 mS/cm. The complete 16S rRNA and ITS genes of the isolates were subsequently sequenced. We found several 16S types related to different lineages of filamentous cyanobacteria in the seven lakes that were supported by ITS data. Two 16S types, belonging to a Leptolyngbya antarctica and Leptolyngbya sp., were each present in two different freshwater lakes. Two different 16S types, both belonging to Leptolynbya antarctica were present in a freshwater and hypersaline lake, which indicates a high ‘intraspecific’ molecular diversity. In order to better understand the adaptation and/or wide tolerance to osmotic stress, we are currently performing ecophysiological experiments with these isolates aimed at assessing the potential local adaptation of these strains to conductivity and desiccation. [less ▲]

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See detailDiversity changes of thelodonts (Thelodonti, Agnatha) in relation to major biotic and abiotic Palaeozoic events
Ferrón, Humberto G.; Turner, Susan; Cascales-Miñana, Borja ULg et al

in 1st International Meeting of Early-stage Researchers in Palaeontology, Alpuente 13-16 2016 (2016, April)

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See detailDiversity dynamics of non-lycopsid lycophytes
Cascales - Miñana, Borja ULg; Meyer-Berthaud, Brigitte

in Cascales - Miñana, Borja; Villanueva-Amadoz, Uxue; Diez, José B. (Eds.) Proceedings of the II Agora Paleobotanica Meeting (Abstract book) (2013, July)

Detailed reference viewed: 20 (0 ULg)