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The use of termite mounds as an alternative to chemical fertilizers has grown in tropical developing countries. Termite mounds also play an important role in ecology and these studies were conducted on dynamic of the reconstruction of termite mounds of the genus Cubitermes in the Bondoé savannah from Central African Republic (CAF). The focus on this particular group may be due to their abundance and conspicuous mounds, compared with the diffuse belowground nests inhabited by soldier less soil-feeding termites. The hypothesis of this work was that the termite mounds of Cubitermes (Cubitermes sankurensis and Cubitermes ugandensis) could be reconstructed after removal of hats, trunks at ground level or when termite mounds are dug up 10 cm below the ground. Five (5) experiments were set up to follow the dynamics of the reconstruction of termite mounds during the dry and rainy seasons. The results show that termite mounds with hats removed in one operation rebuild better the following year (25-30% in the rainy season, 50-60% in the dry season). When the removal was done at ground level, an average of 22.5% reconstruction was recorded in the rainy season and 25-30% reconstruction observed in the dry season after one year. Termite mounds dug 10 cm below the ground did not perform better. The removal of hats during the dry season is an option for the rational management of Cubitermes termite mounds in agriculture in CAR.

The phylogeny of the genus Cubitermes Wasmann was reconstructed using two mitochondrial genes (COI and COII) and a fragment of the nuclear 28S rDNA, including samples of Apilitermes Holmgren, Crenetermes Silvestri, Megagnathotermes Silvestri, and Thoracotermes Wasmann. Based on our analyses, we recovered these genera within a paraphyletic Cubitermes clade. Cubitermes species are distributed between five main clades, highly reflective of their enteric valve armatures (EVAs). Consequently, Cubitermes is here divided into five monophyletic genera based on phylogenetic analyses and EVAs: Cubitermes (sensu stricto), Isognathotermes Sjöstedt, Nitiditermes Emerson, Polyspathotermes Josens & Deligne, gen.n. and Ternicubitermes Josens & Deligne, gen.n. Moreover, the two species of Megagnathotermes included in this study, exhibiting different EVAs, are phylogenetically distant: M. katangensis Sjöstedt belongs in the genus Polyspathotermes, while M. notandus Silvestri remains as a monotypic genus. During the evolution of the Cubitermes complex, sclerotized EVA spatulae appeared twice independently: three or six spatulae in Polyspathotermes (sulcifrons and oblectatus patterns) and two jaw-like spatulae in Nitiditermes (sankurensis pattern), which is absent in some species (oculatus pattern).Zoobank registration: http://zoobank.org/urn:lsid:zoobank.org:pub:576AAFF8-63C6-4962-A8F5-75C9317AEA7B., info:eu-repo/semantics/inPress

Small lenticular soil mounds are scattered in several African savannahs. At Lamto, Cote d’Ivoire, most of these lenticular mounds house nests of Odontotermes aff. pauperans which have to date been thought to have built them. However, repeated observations made in 2000 and 2015 supply several arguments in favour of another hypothesis, namely that after a nest of Macrotermes has been abandoned and eroded, it could be colonized by O. aff. pauperans and subsequently maintained, stabilized, by this latter species or possibly recolonized by another Macrotermes society.

Two species of Cubitermes coexist in the grassy Loudetia Savanna of Bondoe, in the Central African Republic, namely C. sankurensis (Wasmann, 1911) and C. ugandensis (Fuller, 1923) Despite the obvious size difference between individuals their nests have the same general shape but there are significant, though small, differences in height, diameter, number of caps, surface and volume. The closest correlations between these five parameters can be seen between the surface and the volume of the nests. The regressions between these two parameters are identical for both species; the addition of a first cap decreases the volume/surface ratio but a second or third cap does not alter this ratio further. Three apparent age classes have been attributed to the nests based on their external appearance: recent, eroded, and dilapidated. The great density (1297 nests/ha) and abundance of the nests that are dilapidated but still occupied by a declining population clearly suggests that the pressure from predation is weak. This study suggests that the environmental conditions are more influential than the species in shaping the mounds and tentative population dynamics of the termite mounds of Bondoe are outlined.

This article provides a meta-analysis of quantitative data available in literature regarding the relation between termite numbers and the volume of their mounds for 24 species belonging to 13 genera. The leading question behind this analysis is: “how do the respiratory gas exchanges regulate the size of termite mounds?” This question is answered through the analysis of the log–log regression between the volume of the mound and the number of inhabitants. The most confident data support the hypothesis of a respiratory regulation that can be achieved through a relation between the termite numbers and (1) the volume of their mounds (slope of the regression near 1, Noditermes), (2) the surface of the outer walls of their mounds (slope of the regression near 0.67, Termitinae and Nasutitermes) or (3) a compromise between the surface of the outer walls of their mounds and some linear structures of their nests (slope of the regression between 0.67 and 0.33, Trinervitermes and Macrotermes). The way this is achieved is linked with the architecture of the mound. A confident relation was found between the number of individuals and the epigeal volume of their mounds for 18 species for which the most reliable data were provided. Three more accurate models are proposed for estimating the termite population based on the nest material and architecture and on the size of the termites.

(2007). Molecular systematics of Simulium squamosum, the vector in the Kinsuka onchocerciasis focus (Kinshasa, Democratic Republic of Congo) Annals of Tropical Medicine & Parasitology: Vol. 101, No. 3, pp. 275-279.

Diamond's assembly rules predict that competitive interaction between species lead to a non-random co-occurrence of patterns. Earthworms were sampled in five lawns of Roosevelt Avenue (city of Brussels, Belgium) to test the reduced level of co-occurrence of species among earthworm communities. We used null model to generate patterns expected in the absence of species interactions. With the model algorithm that maintains fixed row sums and fixed column sums, species co-occurrence in two out of five islets (5 and 10), was less than the expected; whereas in islets 3, 8 and 9, species assemblage seemed random. This study indicates that the non-random selection observed in the two lawns is because there is an interaction between species close to the same ecological category.

The growth and demography ofCubitermes speciosus mounds were studied in an equatorial forest ecosystem near Kisangani, Zaire. The mounds were censused and measured on eight occasions from June 1985 to January 1993 on 25 plots of 100 m2. Mounds were found to grow in two ways: either they were enlarged sporadically, leading to a correlation between age and size; or they were no longer enlarged after a 2-year period of initial growth, which means that both large and small mounds can be old. The number of living mounds was fairly constant: it varied between 112 and 152 ha−1 with an average of 139 ha−1, and about a quarter of them were renewed each year. However, a clear tendency was observed over our 7.5-year observation period: the average size of the mounds increased regularly and was 2.7 times larger in 1993 than in 1985. Monthly birth and death rates were estimated using a model of continuous growth. Life expectancy at the age of 3 months was estimated from a survivorship curve at 3.5 years.

Earthworms were studied at six sites along a gradient of urbanization and their relations with several soil abiotic factors were determined. Concentrations of heavy metals, calcium and magnesium in earthworms and in soils were measured by atomic absorption spectroscopy. Strong negative correlations were detected between earthworm density and soil concentrations of cadmium and magnesium. Earthworm biomass was negatively correlated with lead, copper and zinc, and positively correlated with the distance from the centre of the city. High concentrations of Cd and Zn (concentration factors 49 and 32) were accumulated by earthworms in contrast to those of Cu and Pb (2 and 1). Relations between worm and soil concentrations of heavy metals, Ca and Mg are discussed.

Naar aanleiding van de inwerkingtreding van de Europese Kaderrichtlijn Water (KRW) in 2000, werden grote inspanningen geleverd om de ecologische toestand van diverse typen waterlichamen in Europa op een uniforme en wetenschappelijk gefundeerde wijze te karakteriseren. Voor de biomonitoring beschreven in dit rapport, werd gebruik gemaakt van macrofyten, diatomeeën (als onderdeel van fytobenthos), fytoplankton en macro-invertebraten (aangevuld met gegevens over biologie-ondersteunende fysicochemie), om de ecologische toestand te bepalen van 9 verschillende sterk veranderde waterlopen, het Kanaal Charleroi-Brussel-Schelde, en 17 vijvers in het Brussels Hoofdstedelijk gewest (BHG), in de studieperiode 2009 en 2010. Enkele locaties werden in 2004 en 2007 bestudeerd, zodat voor deze punten een langere tijdsreeks beschikbaar is. Voor een aantal staalnamepunten werden additionele gegevens uit 2011 of verwant onderzoek toegevoegd. In de waterlopen exclusief het kanaal werden macrofyten, fytobenthos en macro-invertebraten geanalyseerd, in het kanaal fytobenthos, fytoplankton en macro-invertebraten, en in de vijvers macrofyten, fytoplankton en - voor een deel van de vijvers - macro-invertebraten. De berekening van de Ecological Quality Ratio (EQR), gebruikt om de relatieve afwijking t.o.v. het Maximaal Ecologisch Potentieel (MEP) weer te geven, gebeurde volgens de methoden beschreven in voorgaande rapporten, hoewel enkele methodologische aanpassingen werden doorgevoerd. In de studieperiode 2009-2010 werd het Goed Ecologisch Potentieel (GEP), de minimale doelstelling vastgelegd in de Kaderrichtlijn Water, voor het geheel van onderzochte biologische waterkwaliteitselementen (uitgaande van het One-out-All-out-principe) 9 keer gerealiseerd. In de Woluwe te Hof ter Musschen (2010), de Kleine Mellaertsvijver (2010) en de lange vijver van het Woluwepark (2009) werd het GEP slechts in één van beide jaren bereikt, terwijl de Tenreukenvijver, de vijver Verdronken Kinderen 2, en de Watermaalvijver zich in beide jaren in een gunstige globale ecologische toestand bevonden. Uit de set van onderzochte waterlichamen blijkt duidelijk dat de vijvers gemiddeld in een betere ecologische toestand verkeren - en de lentische ecosystemen zich dus dichter bij het globale GEP bevinden - dan het geval is voor de waterlopen. Op veel plaatsen in de waterlopen zijn fysisch-chemische waterkwaliteit, een lage nichediversiteit en beschaduwing en verruiging van oevers belangrijke belemmerende factoren voor het ophalen van de ecologische kwaliteit. Voor vijvers is de stabiliteit van de helderwatertoestand een cruciaal element, maar omdat watergebonden oevervegetatie meegerekend wordt in het kwaliteitsoordeel, speelt ook de structuur van de littorale zone een aanzienlijke rol. Temporele evoluties waren zelden uitgesproken binnen de studieperiode 2009-2010, behalve voor vijvers die balanceerden tussen een heldere en troebele toestand, of verschillende stadia van troebelheid doormaakten. De ecologische kwaliteit in de Woluwe aan Hof ter Musschenscheen gestaag verbeterd te zijn sinds 2004: in 2010 werd voor alle onderzochte kwaliteitselementen het GEP gehaald. De aanzienlijke verbetering van de Zenne bij het uitstromen van het BHG geobserveerd in de periode 2004-2007 bleek niet duurzaam te zijn. Voor fytobenthos en macro-invertebraten werd op dit punt in de Zenne t.o.v. 2007 een klassevermindering waargenomen in 2009-2010. Onder de huidige omstandigheden bevindt de Zenne zich bij buitenkomst van de Brusselse agglomeratie ver van de doelstellingen vastgelegd in de KRW. Voor het biologische kwaliteitselement macrofyten in de vijvers werden vegetatiegegevens aangevuld met het kolonisatiepotentieel van de propagulenbank, geanalyseerd a.d.h.v. ontkiemingsproeven vanuit sediment. De ontkiemingsproeven en vegetatieopnamen toonden een significant verband tussen rijkdom van de propagulenbank en abundantie van de gevestigde submerse vegetatie later in het jaar, maar niet in alle vijvers met een rijke propagulenvoorraad werd het potentieel gerealiseerd. Daarentegen bleek wel dat de kans op macrofytengroei en het daarvan afhankelijke helderwaterequilibrium klein was in vijvers met een laag propagulenpotentieel. In die gevallen kan beheer gericht worden op actieve stimulatie van vroege groei van submerse macrofyten (d.m.v. inoculatie met propagulenrijk sediment of aanbrengen en beschermen van stichterkolonies), om het gebrek aan propagulen in de bodem te compenseren. Een direct belang van een ongehinderde propagulendispersie blijkt uit de koppeling tussen de vegetatiegemeenschappen aangetroffen in de Tenreukenvijver en het stroomafwaarts daarvan gelegen deel van de Woluwe in het Senypark. De EQR voor macrofyten in dit deel van de Woluwe stemde overeen met het GEP, en de overeenkomsten tussen submerse vegetaties in beide waterlichamen toonden indirect aan dat de aanvoer van geslachtelijke en vegetatieve voortplantingsstructuren vanuit de Tenreukenvijver deze toestand stimuleerde. In dit rapport worden in het eerste deel de resultaten voor macrofyten, fytobenthos en fytoplankton besproken, terwijl het tweede deel de kwaliteit o.b.v. macro-invertebraten beschrijft. In het derde deel wordt de algemene ecologische en fysisch-chemische toestand van de individuele staalnamepunten besproken, en wordt een overzicht gegeven van de knelpunten die in de loop van deze studie werden geïdentificeerd.

The foraging activities of four genera (six species) of grassland ants (Formica rufibarbis, Tapinoma erraticum, Myrmica schenki, M. sabuleti, Tetramorium caespitum andT. impurum) were observed in June–July 1985 at Treignes (Belgium).

Coelomic fluid of the Lumbricid Eisenia fetida contains a 42-kDa pattern recognition protein named coelomic cytolytic factor (CCF) that binds microbial cell wall components and triggers the activation of the prophenoloxidase cascade, an important invertebrate defense pathway. Here we report on the sequence characterization of CCF-like molecules of other Lumbricids: Aporrectodea caliginosa, Aporrectodea icterica, Aporrectodea longa, Aporrectodea rosea, Dendrobaena veneta, Lumbricus rubellus and Lumbricus terrestris, and show that CCF from E. fetida has a broader saccharide-binding specificity, being the only one recognizing N,N'-diacetylchitobiose. We suggest that the broad recognition repertoire of E. fetida CCF reflects a particular microbial environment this species lives in.

Samples issued from intensive sampling in the Netherlands (1992–2001) and from extensive sampling carried out in the context of international campaigns (1998, 2000 and 2001) were revisited. Additional samples from artificial substrates (1992–2003) and other techniques (various periods) were analysed. The combined data provide a global and dynamic view on the Peracarida community of the River Meuse, with the focus on the Amphipoda. Among the recent exotic species found, Crangonyx pseudogracilis is regressing, Dikerogammarus haemobaphes is restricted to the Condroz course of the river, Gammarus tigrinus is restricted to the lowlands and seems to regress, Jaera istri is restricted to the ‘tidal’ Meuse, Chelicorophium curvispinum is still migrating upstream into the Lorraine course without any strong impact on the other amphipod species. After a rapid expansion Dikerogammarus villosus has continued its upstream invasion between 1998 and 2002 at a rate of 30–40 km per year, but no further progression was noticed in 2003. Locally and temporarily the native species (Gammarus fossarum and G. pulex) and naturalized species (G. roeseli and Echinogammarus berilloni) may have been excluded by the most recent invaders (mainly D. villosus), but none of the native and naturalized species has disappeared completely. Therefore, the number of amphipod species found in the River Meuse has increased. Moreover, the native and naturalized species keep on dominating the tributaries from which the recent invaders seem to be excluded. A changing Peracarida community structure is observed along the course of the River Meuse: four native or naturalized species inhabit the upstream (Lorraine) course, three invasive species dominate in the middle reach (Ardenne-Condroz zone), one exotic species is housed in the Border Meuse and three or four invasive species dominate the assemblages in the lowlands.

The consumption and growth of Abax ater Villers were measured over the whole life cycle under summer conditions in the laboratory.

Respiration of Abax ater Villers was measured in a Gilson differential respirometer under various conditions. The main factors influencing respiration were found to be temperature, food consumption, and locomotor activity. Circadian rhythm played a minor role, and metabolic acclimation was absent under most conditions.

The larvae of Issoria lathonia L. feed in natural conditions on several Viola spp. among which are the zinc-accumulating Viola calaminaria (Gingins) Lej. and the nonmetal-accumulating Viola tricolor L. To examine how I. lathonia caterpillars cope with the naturally high foliar zinc concentration of V. calaminaria, we compared the growth of caterpillars reared on leaves varying in zinc concentration. Larvae were fed in controlled conditions with V. calaminaria and V. tricolor grown on noncontaminated soil (i.e. two low-Zn diets) and with V. calaminaria grown on zinc-enriched soil (i.e. one high-Zn diet). Larvae had a higher growth rate when fed with noncontaminated V. calaminaria compared to zinc-enriched V. calaminaria, suggesting that zinc slows down larval growth. However, larvae consumed more leaves of zinc-enriched V. calaminaria (+45%; estimated from fecal mass) compared with noncontaminated V. calaminaria, suggesting that zinc accumulation would not be advantageous to plants. Caterpillars reared on high-zinc leaves regulate their internal zinc concentration through excretion of highly metal-concentrated feces. When kinetics of growth on both low-zinc diets were compared, it appeared that larval development was faster on noncontaminated V. calaminaria than on V. tricolor. This suggests that more nutrients or less feeding inhibitors in V. calaminaria account for fastest growth. Developmental rates on V. tricolor and on zinc-enriched V. calaminaria were similar, despite the high leaf zinc concentration of the latter species. Together with the abundance of V. calaminaria on calamine soils, this may explain why the largest populations of I. lathonia develop on V. calaminaria in Belgium., FLWIN, info:eu-repo/semantics/published

The diterpene composition of the defensive secretions of minor and major soldiers is described for four sympatricTrinervitermes from the Ivory Coast. The degree of intra- and interspecific similarity between the secretions is assessed and related to available information on soldier behavior. A significant chemical dimorphism is observed between minor and major soldiers ofT. geminatus andT. togoensis. Both species build extensive foraging trails in the open air. During these excursions, the workers are protected by numerous minor soldiers, but only a few major ones. Internest comparison inT. geminatus suggests that the differences between minor and major soldiers is as large within a nest as between different nests. By, contrast, inT. trinervius andT. oeconomus both types of soldiers produce very similar secretions. The foraging habits of those species are far more cryptic. The first species builds earthen tunnels, and the second one forages in close proximity to its nest under cover of vegetation.

Le poids frais, le poids sec, la teneur en eau, l'equivalent energetique et la teneur en cendres ont ete mesurees pour la plupart des castes et stades deTrinervitermes geminatus dans la region de Lamto (Cote d'Ivoire).

Des enregistrements de temperatures ont ete effectues dans des termitieres deTrinervitermes geminatus Wasmann et dans le sol en juin 1968, puis en janvier 1969, avant, pendant et apres le passage des feux de brousse. Les termitieres deTrinervitermes geminatus Wasmann, partiellement epigees, sont soumises a de fortes variations de temperature en surface, en relation avec l'eclairement et les pluies. De meme que dans le sol, ces variations se propagent lentement dans la termitiere et s'attenuent avec la profondeur: leur amplitude passe de 40° C environ au sommet de la termitiere a 2 ou 3° C dans les loges souterraines, amplitude egalement observee dans le sol a profondeur equivalente. Sans que l'on puisse parler de regulation thermique de la part des termites, il existe neanmoins une relation entre la temperature au centre du nid et la taille de ce nid: l'amplitude thermique journaliere des nids de grande taille etant nettement plus faible que celle des petits nids. Ceci ne resulte probablement que de l'inertie thermique qui est plus importante dans les grandes termitieres. L'influence immediate du passage des feux de brousse se revele negligeable: elle ne se manifeste qu'en surface de la partie epigee du nid.

Biological plant invasions pose a serious threat to native biodiversity and have received much attention, especially in terrestrial habitats whereas in freshwater ecosystems impacts of invasive plant species are less studied. We hypothesize an impact on organisms from the water column, but also from the sediment and assessed the impact of three aquatic invasive species Hydrocotyle ranunculoides, Ludwigia grandiflora and Myriophyllum aquaticum on plants and macroinvertebrates. Our results in 32 ponds in Belgium indicate that the reduction in native plant species richness was a common pattern to invasion. However, the magnitude of impacts were species specific. A strong negative relationship to invasive species cover was found, with submerged vegetation the most vulnerable to the invasion. Invertebrate richness, diversity and abundance were measured in sediments of uninvaded ponds and in invaded ponds along a gradient of H. ranunculoides, L. grandiflora, and M. aquaticum species cover. We found a strong negative relationship between invasive species cover and invertebrate abundance, probably due to unsuitable conditions of the detritus for invertebrate colonization. Taxonomic compositions of aquatic invertebrate assemblages in invaded ponds differed from uninvaded ponds. Sensitive benthos such as mayflies were completely absent in invaded ponds. The introduction of H. ranunculoides, L. grandiflora, and M. aquaticum in Belgian ponds has caused significant ecological alterations in the aquatic vegetation and the detritus community of ponds.