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Invasive plants alter community structure, threatening ecosystem function and biodiversity, but little information is available on whether invasive species richness responds to environmental conditions in the same way that richness of native plants does. We surveyed submerged and floating-leaved plants in 99 Connecticut (northeast USA) lakes and ponds, collecting quantitative data on abundance and frequency. We used multiple linear and logistic regression to determine which environmental conditions were correlated with species richness of invasive and native plants. Independent variables included lake area, maximum depth, pH, alkalinity, conductivity, phosphorus concentration, productivity, and dominance (the proportional abundance of the most abundant and frequently found species), plus two estimates of human activity. Species richness of both native and invasive richness was correlated with alkalinity and human activity. Native richness also increased with water clarity, lake area, and productivity; invasive species richness also rose with pH. We found no evidence that richness of one group affected richness of the other. We also investigated patterns of dominance and found that native plants were as likely to become dominant as invasive species. Dominance occurred overwhelmingly in shallow lakes with high productivity. Key words: abiotic conditions, biodiversity, community structure, dominance, lakes, macrophyte. Les plantes envahissantes modifient la structure des communautes en menacant les fonctions des ecosystemes et leur biodiversite, mais on connait peu de chose a savoir si la richesse en especes envahissantes reagit aux conditions du milieu de la meme facon que la richesse en plantes indigenes. Les auteurs ont suivi les plantes submergees et a feuilles flottantes dans 99 lacs et etang du nord-est des Etats-Unis, en reunissant les donnees d'abondance et de frequence. Ils ont utilise la regression lineaire multiple et logistique pour determiner quelles conditions environnementales montrent une correlation avec les richesses en especes des plantes envahissantes et indigenes. Les variables independantes comprennent la surface des lacs, la profondeur maximum, le pH, l'alcalinite, la conductivite, la teneur en phosphore, la productivite et la dominance (l' abondance proportionnelle des especes les plus frequentes et les plus abondantes), ainsi que deux valeurs estimees pour l'activite humaine. La richesse en especes indigenes aussi bien qu'en especes envahissantes montre une correlation avec l'alcalinite et l'activite humaine. La richesse en especes indigenes augmente egalement avec la clarte de l'eau, la surface du lac et la productivite; la richesse en especes adventices augmente aussi avec le pH. On ne percoit aucune preuve que la richesse d'un groupe affecte la richesse de l'autre. Les auteurs ont egalement examine le patron de la dominance pour constater que les plantes indigenes ont autant de chance de devenir dominantes que les especes envahissantes. On retrouve la dominance surtout dans les lacs peu profonds a forte productivite. Mots-cles : conditions abiotiques, biodiversite, structure des communautes, dominance, lacs, macrophytes. [Traduit par la Redaction], Introduction Invasive plants are an economic and ecological problem in many aquatic systems (Pimentel et al. 2005). They can dominate lakes, interfering with recreation and reducing real estate values (Bergstrom [...]

This article documents the addition of 205 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Bagassa guianensis, Bulweria bulwerii, Camelus bactrianus, Chaenogobius annularis, Creontiades dilutus, Diachasmimorpha tryoni, Dioscorea alata, Euhrychiopsis lecontei, Gmelina arborea, Haliotis discus hannai, Hirtella physophora, Melanaphis sacchari, Munida isos, Thaumastocoris peregrinus and Tuberolachnus salignus. These loci were cross-tested on the following species: Halobaena caerulea, Procellaria aequinoctialis, Oceanodroma monteiroi, Camelus ferus, Creontiades pacificus, Dioscorea rotundata, Dioscorea praehensilis, Dioscorea abyssinica, Dioscorea nummularia, Dioscorea transversa, Dioscorea esculenta, Dioscorea pentaphylla, Dioscorea trifida, Hirtella bicornis, Hirtella glandulosa, Licania alba, Licania canescens, Licania membranaceae, Couepia guianensis and 7 undescribed Thaumastocoris species. [ABSTRACT FROM AUTHOR]