5 research outputs found
Abundance, Richness, Seasonal and Altitudinal Dynamics of Aquatic True Bugs (Heteroptera) in Mountain Wetlands of Argentina
Mountain wetlands provide unique information because their biota is highly specific and contributes significantly to regional diversity. The goals of this study were assessing altitudinal and temporal variation in the distribution of Heteropteran assemblages in mountain wetlands; and studying the phenology of the most abundant species. All stages of Heteroptera and data on environmental variables were collected monthly over one year from five mountain wetlands. A simple community structure, and also a low richness of aquatic true bugs, composed of four Heteropteran families (Corixidae, Belostomatidae, Notonectidae and Gelastocoridae), characterized our ponds. Richness and abundance varied temporally and spatially (p < 0.0001); and increased at higher elevations. Additionally, the highest abundance of cold stenothermal species occurred at the highest altitudes where harsh conditions are prevalent. Ectemnostega (E.) quadrata and S. (T.) jensenhaarupi, both endemic to the Andes region, were the most abundant species. Both these species showed univoltine cycles and overwintered as adults. Biodiversity of the Heteroptera reached maximum values in summer when water temperature increased. Temporal and spatial monitoring studies provide key information on the distribution, diversity, and habitat requirements of Heteropteran species as well as on conservation and management of these vulnerable habitats and species which are faced with climate warming.Facultad de Ciencias Naturales y Muse
Potential geographic distributions of two parthenogenetic weevils (Coleoptera: Curculionidae) associated with citrus in Argentina and Brazil
Parapantomorus fluctuosus (Boheman) and Pantomorus cinerosus (Boheman) (both Coleoptera: Curculionidae) are parthenogenetic broad-nosed weevils native to South America, and they damage citrus in Argentina and Brazil. The objectives of this contribution are to apply ecological niche modelling to compare the suitable areas of occurrence of these species with those of other parthenogenetic Naupactini distributed in similar areas, and to analyze their potential range in relation to the distribution of citrus groves, mainly in Argentina and Brazil. Pantomorus cinerosus and P. fluctuosus were predicted to be distributed in tropical and subtropical South America, Mexico, Central America, Cuba, southeastern USA (Florida), southern Africa, Madagascar, eastern Australia, and southern China. However, neither has colonized other countries outside the native range. The potential distribution of P. fluctuosus is broader than that of P. cinerosus, and the predicted areas of both species are partially coincident with main production areas of citrus in Argentina, Brazil, and throughout the world. Although ecological niche modelling is an effective tool for predicting the potential spread and colonization of weevils in distant cultivated areas, weevil establishment is most likely the result of multiple factors.Parapantomorus fluctuosus (Boheman) y Pantomorus cinerosus (Boheman) (ambos Coleoptera: Curculionidae) son gorgojos partenogenéticos de rostro corto nativos de América del Sur, que causan daños en cítricos, en Argentina y Brasil. Los objetivos de esta contribución son realizar un análisis de modelado de nicho ecológico de estas especies, comparar las áreas óptimas modeladas con las de otras especies partenogenéticas de Naupactini de similar distribución, y analizar sus distribuciones potenciales con respecto a las zonas productoras de cítricos principalmente de Argentina y Brasil.
De acuerdo con nuestros resultados, Parapantomorus fluctuosus y Pantomorus cinerosus presentan condiciones ambientales favorables en Sudamerica tropical y subtropical, América Central, México, Cuba, sureste de Estados Unidos (Florida), sur de África, Madagascar, este de Australia, y sur de China; sin embargo ninguna de ellas ha colonizado otros países fuera de su rango natural. La distribución potencial de P. fluctuosus es mas amplia que la de P. cinerosus y las áreas predichas para ambas especies son parcialmente coincidentes con las regiones de cultivo de cítricos en Argentina, Brasil y a lo largo del mundo. El modelado de nichos ecológicos es una herramienta de utilidad para estimar la posible dispersión y colonización a distancia de plagas de gorgojos, sin embargo, su establecimiento en dichas áreas sea probablemente el resultado de múltiples factores.Facultad de Ciencias Naturales y Muse
Verbal processes in academic language in Spanish: exploring discourse genres within the systemic functional framework
A Systemic-Functional Analysis of English Language Learners' Writing
This article presents a systemic-functional linguistic analysis of two writing samples of the University of California Analytical Writing Placement (AWP) Examination written by English language learners (ELLs). The analysis shows the linguistic features utilized in the two writing samples, one that received a passing score and one that received a failing score. The article describes some of the grammatical resources which are functional for expository writing, which are divided under three main categories: textual, interpersonal, and ideational resources. Following this brief description is the analysis of both essays in terms of these resources.. The configuration of grammatical features used in the essays make up the detached style of essay 1 and the more personal style of essay 2. These grammatical features include the textual resources of thematic choices and development, clause-combining strategies (connectors), and lexical cohesion; interpersonal resources of interpersonal metaphors of modality; and ideational resources of nominalization and abstractions as ideational metaphors. Implications for educational practice and recommendations for educators based on the analysis are provided