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The aim of the present article is to analyze the influence of the river landscape in the land market of the city of La Plata. Methodologically, a qualitative-quantitative work is developed, structured on a price survey carried out on two water courses located on the northern periphery of the city: the Gato stream and the Rodríguez stream. This study has compared not only the land value structure in both streams, but also the differences between course-bordering lots and neighboring lots. The results show the incidence of the water landscape in the urban land market, and the price variations in different areas of the course, as well as between both cases studied, also taking into account the landscape consideration that the stream acquires in some neighborhoods. [ABSTRACT FROM AUTHOR]

Summary: Monitoring the diversity and structure of plant-parasitic nematode (PPN) communities together with developing appropriate control strategies can reduce the occurrence of these pathogens and other plant pests in horticultural crops. In this context a study of the abundance, frequency, diversity and distribution of PPN in horticultural soils under glasshouse conditions from the Green Belt of La Plata, Buenos Aires, Argentina, under different management systems was undertaken. Soil samples were collected from three horticultural areas with different tomato crop managements: agroecological crop (AC); organic crop with Brassicaceae soil amendments (OC); intensive conventional crop treated with methyl bromide (MeBr) (IC). The parameters evaluated were: nematode genera richness (G); Shannon-Wiener diversity index ( H ′ ) (Hutcheson's t -test was applied for this index); equitability index (E); abundance; and frequency of genera. ANOSIM and SIMPER statistical analyses were performed to find significant differences between the nematode assemblages from the different sites. A total of 14 genera of PPN were identified among the three crop sites. Members of the feeding habits categories ectoparasites, semi-endoparasites, migratory endoparasites and sedentary endoparasites were observed. Statistical analysis enabled us to characterise each site based on the composition of the nematode assemblages. Helicotylenchus , Tylenchus and Nacobbus were the most frequent and abundant genera. AC and OC showed similar values of richness and diversity; the crop treated with MeBr (IC) showed the lowest diversity of PPN. [ABSTRACT FROM AUTHOR]

Copyright of Divergencia is the property of Taller de Historia Politica 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.)

Copyright of Cuadernos de H Ideas is the property of Universidad Nacional de La Plata 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.)

The subfamily Potamotrygoninae, the only extant clade of elasmobranchs exclusive to freshwater environments, encompasses four genera and 38 species distributed across almost every major South American river basin. Despite their importance in the ornamental fish trade, the taxonomy and evolutionary relationships within potamotrygonines have not yet been resolved. Here, we present a comprehensive molecular phylogeny for the Neotropical freshwater stingrays, based on extensive species and population sampling (35 species and > 350 individuals from drainages across South America). Our phylogeny corroborates the monophyly of the genera Paratrygon and Heliotrygon and the monophyly of the Potamotrygon + Plesiotrygon clade. Within the Potamotrygon + Plesiotrygon clade, we identify a core Potamotrygon clade characterized by short branches, low nodal support and incongruence with current species-level taxonomy. In the core Potamotrygon clade, specimens of widespread species, such as Potamotrygon motoro and Potamotrygon orbignyi , do not form monophyletic lineages; instead, specimens from these species are often closely related to those of other species from the same river basins. These patterns could be caused by inaccurate taxonomy, hybridization, incomplete lineage sorting and rapid diversification. We discuss the conservation of Neotropical freshwater stingrays from a phylogenetic perspective and suggest ways to prioritize potamotrygonid conservation efforts with respect to endemism and evolutionary distinctiveness. [ABSTRACT FROM AUTHOR]

The aging of population arises as a current demographic phenomenon, at present consolidated in both European and Latin American cities. However, aging rates are unevenly distributed across cities, in a particular dialogue with areas of urban vulnerability. The aim of the article is to show the recent evolution of the urban demographic aging process and its unequal socio-spatial distribution in the cities of Seville (Spain) and La Plata (Argentina), analyzing its relationship with scenarios of social vulnerability and housing in a comparative quantitative perspective, as it could result in processes of risk. The methodology used is quantitative, focused on analysis of official statistical sources (censuses, land registers, cadastre). The results obtained show the importance of considering demographic aging as an end stage of the neighborhood life cycle, rather than a condition for urban vulnerability. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Sociologia is the property of Universidad Nacional de Colombia, Facultad de Ciencias Humanas, Departamento de Sociologia 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.)

Copyright of Estudios del Hábitat is the property of Universidad Nacional de La Plata 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.)

Inventorying biodiversity is fundamental to overcoming knowledge shortfalls in species discovery and description (Linnean shortfall), their distributions (Wallacean shortfall) and abiotic niches (Hutchinsonian shortfall). However, inventorying efforts often show spatial biases, and the underlying causes have only been explored at large spatial extents for the most well-known terrestrial taxa. Improving our understanding of these biases and their drivers is particularly crucial in the speciose tropics, where biodiversity knowledge suffers the most from knowledge shortfalls. Using the most complete information available on freshwater fish distributions in three regions in the Neotropics (Orinoco and Trans-Andeans, the Amazon and the La Plata basins), first, we evaluated environmental biases in inventory effort and completeness across sub-basins. Further, we examined three hypotheses (Accessibility , Appeal , and Safety) to explain the differences in contemporary (2000–2018) inventorying efforts. The Accessibility and Appeal hypotheses were well-supported and conjointly explained a moderate proportion of the spatial variation in the inventorying effort. By contrast, the Safety hypothesis predictors showed limited support. The most accessible sub-basins (i.e., lower travel time from cities or closer to fluvial ports) experienced higher inventorying effort regarding the number of unique inventorying locations and years inventoried. Our results suggest that differences in Accessibility alone may be insufficient to explain inventorying biases. Inventorying efforts were also biased against sub-basins with lower biodiversity and habitat diversity, showing preferential sampling driven by sub-basins' Appeal. The imprint driven by Appeal elucidates opportunities to coordinate future efforts to fill the shortfalls of biodiversity knowledge more efficiently for the Neotropical fish fauna. • Freshwater fish inventory effort and completeness is environmentally biased in the Neotropics. • A small percentage of sub-basins have near-complete fish inventories. • The accessibility and appeal of sub-basins drive contemporary inventory efforts. • Sub-basins with lower biodiversity and habitat diversity have received less inventorying effort. • Opportunities exist to coordinate efforts to fill shortfalls in Neotropical fish fauna knowledge. [ABSTRACT FROM AUTHOR]