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1.
Conserv Biol ; 36(4): e13885, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35040183

RESUMO

Area protection is a major mechanism deployed for environmental conservation in Antarctica. Yet, the Antarctic protected areas network is widely acknowledged as inadequate, in part because the criteria for area protection south of 60°S are not fully applied. The most poorly explored of these criteria is the type locality of species, which provides the primary legal means for Antarctic species-based area protection and a method for conserving species even if little is known about their habitat or distribution. The type locality criterion has not been systematically assessed since its incorporation into the Protocol on Environmental Protection to the Antarctic Treaty in 1991, so the extent to which the criterion is being met or might be useful for area protection is largely unknown. To address the matter, we created and analyzed a comprehensive database of Antarctic type localities of terrestrial and lacustrine lichens, plants, and animals. We compiled the database via a literature search of key taxonomic and geographic terms and then analyzed the distance between type localities identifiable to a ≤ 25km2 resolution and current Antarctic Specially Protected Areas (ASPAs) and human infrastructure. We used a distance-clustering approach for localities outside current ASPAs to determine candidate protected areas that could contain these unprotected localities. Of the 386 type localities analyzed, 108 were within or overlapped current ASPAs. Inclusion of the remaining 278 type localities in the ASPA network would require the designation of a further 105 protected areas. Twenty-four of these areas included human infrastructure disturbance. Given the slow rate of ASPA designation, growing pace of human impacts on the continent, and the management burden associated with ASPAs, we propose ways in which the type locality criterion might best be deployed. These include a comprehensive, systematic conservation planning approach and an alternative emphasis on the habitat of species, rather than on a single locality.


Mejoría de la Protección Basada en Especies de Áreas en la Antártida Resumen La protección de áreas es un mecanismo importante implementado para la conservación ambiental en la Antártida. Sin embargo, generalmente se identifica como inadecuada a la red de áreas antárticas protegidas porque no se aplican totalmente los criterios para la protección de áreas al sur de los 60°S. De estos criterios, el menos explorado es el de la localidad tipo de las especies, el cual proporciona el principal medio legal para la protección basada en las especies de áreas en la Antártica y un método para la conservación de especies, incluso si se sabe poco sobre su hábitat o distribución. El criterio de la localidad tipo no ha sido evaluado sistemáticamente desde que se incorporó al Protocolo Ambiental del Tratado Antártico en 1991, por lo que se desconoce en gran parte el grado al que se cumple el criterio o cuán útil podría ser para proteger el área. Creamos y analizamos una base de datos integral de las localidades tipo de líquenes, plantas, y animales terrestres y lacustres para abordar este tema. Compilamos la base de datos a partir de la búsqueda de términos geográficos y taxonómicos relevantes en la literatura y después analizamos la distancia entre las localidades tipo identificables a una resolución ≤25km2 y las Áreas Especialmente Protegidas de la Antártida (AEPA) existentes y la infraestructura humana. Usamos una estrategia de agrupamiento de distancias para las localidades externas a las AEPA existentes para determinar áreas protegidas candidatas que podrían albergar estas localidades sin protección. De las 386 las localidades tipo analizadas, 108 estaban dentro de o se traslaparon con las AEPA existentes. La inclusión de las otras 278 localidades tipo dentro de la red AEPA requeriría de la designación de 105 áreas adicionales. En 24 de estas áreas existieron alteraciones por la infraestructura humana. Debido al ritmo lento de designación de AEPA, el avance del impacto humano en el continente y el costo de la gestión asociado con las AEPA, proponemos algunas formas en las que podría implementarse de mejor manera el criterio de la localidad tipo. Estas formas incluyen una estrategia sistemática e integral de la planeación de la conservación y un énfasis alternativo en el hábitat de la especie en lugar de en una sola localidad.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Regiões Antárticas , Ecossistema , Humanos , Líquens , Plantas
2.
Oecologia ; 195(4): 873-885, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33792777

RESUMO

Trait-environment interactions have contributed to the remarkable plant radiations in the Cape Floristic Region (CFR) of southern Africa. Whether such interactions have also resulted in the diversification of the invertebrate fauna, independently of direct associations with plants is, however, not clear. One candidate where this may be the case is the unusually diverse Collembola genus Seira. Including 89 species in the CFR, many of which are localised habitat specialists, this genus includes many species inhabiting the warm, dry fynbos shrubland-a habitat atypical of usually desiccation-sensitive Collembola. Here, we investigate whether desiccation tolerance may have contributed to the considerable diversity of Seira in the CFR. First, we demonstrate, by measuring vapour pressure deficits (VPD) of the species' microhabitats (fynbos shrubland and moister Afrotemperate Forests), that the fynbos shrublands are dry environments (mean ± S.E. maximum VPD 5.2 ± 0.1 kPa) compared with the Afrotemperate Forest patches (0.3 ± 0.02 kPa) during the summer activity period of Seira. Then we show that Seira species living in these shrublands are more desiccation tolerant (mean ± S.E. survival time at 76% relative humidity: 74.3 ± 3.3 h) than their congeners in the cooler, moister Afrotemperate Forests (34.3 ± 2.8 h), and compared with Collembola species globally (3.7 ± 0.2 h). These results, and a previous demonstration of pronounced thermal tolerance in the fynbos shrubland species, suggest that the diversity of Seira in the CFR is at least partly due to pronounced desiccation and thermal tolerance, which has enabled species in the genus to exploit the hot and dry habitats of the CFR.


Assuntos
Artrópodes , Dessecação , Animais , Ecossistema , Filogenia , Plantas
3.
Pediatr Emerg Care ; 36(11): e600-e605, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30985631

RESUMO

OBJECTIVE: The majority of the children with a central line who present to the emergency department with fever or other signs of bacteremia do not have a central line-associated bloodstream infection (CLABSI). Our objective was to develop a clinical prediction model for CLABSI among this group of children in order to ultimately limit unnecessary hospital admissions and antibiotic use. METHODS: We performed a nested case-control study of children with a central line who presented to the emergency department of an urban, tertiary care children's hospital between January 2010 and March 2015 and were evaluated for CLABSI with a blood culture. RESULTS: The final multivariable model developed to predict CLABSI consisted of 12 factors: age younger than 5 years, black race, use of total parenteral nutrition, tunneled central venous catheter, double-lumen catheter, absence of other bacterial infection, absence of viral upper respiratory tract infection symptoms, diarrhea, emergency department temperature greater than 39.5°C, fever prior to presentation, neutropenia, and spring/summer season. The clinical prediction score had good discrimination for CLABSI with a c-statistic of 0.81 (confidence interval, 0.77-0.85). A cut point less than 6 was associated with a sensitivity of 98.5% and a negative predictive value of 99.2% for CLABSI. CONCLUSIONS: We were able to identify risk factors and develop a clinical prediction model for CLABSI in children presenting to the emergency department. Once validated in future study, this clinical prediction model could be used to assess the need for hospitalization and/or antibiotics among this group of patients.


Assuntos
Bacteriemia/diagnóstico , Infecções Relacionadas a Cateter/diagnóstico , Cateterismo Venoso Central/efeitos adversos , Adolescente , Fatores Etários , Bacteriemia/etnologia , Hemocultura , Estudos de Casos e Controles , Infecções Relacionadas a Cateter/etnologia , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco
4.
Curr Res Insect Sci ; 3: 100051, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36591563

RESUMO

Biological invasions have significant ecological and economic impacts. Much attention is therefore focussed on predicting establishment and invasion success. Trait-based approaches are showing much promise, but are mostly restricted to investigations of plants. Although the application of these approaches to animals is growing rapidly, it is rare for arthropods and restricted mostly to investigations of thermal tolerance. Here we study the extent to which desiccation tolerance and its phenotypic plasticity differ between introduced (nine species) and indigenous (seven species) Collembola, specifically testing predictions of the 'ideal weed' and 'phenotypic plasticity' hypotheses of invasion biology. We do so on the F2 generation of adults in a full factorial design across two temperatures, to elicit desiccation responses, for the phenotypic plasticity trials. We also determine whether basal desiccation resistance responds to thermal laboratory natural selection. We first show experimentally that acclimation to different temperatures elicits changes to cuticular structure and function that are typically associated with water balance, justifying our experimental approach. Our main findings reveal that basal desiccation resistance differs, on average, between the indigenous and introduced species, but that this difference is weaker at higher temperatures, and is driven by particular taxa, as revealed by phylogenetic generalised least squares approaches. By contrast, the extent or form of phenotypic plasticity does not differ between the two groups, with a 'hotter is better' response being most common. Beneficial acclimation is characteristic of only a single species. Laboratory natural selection had little influence on desiccation resistance over 8-12 generations, suggesting that environmental filtering rather than adaptation to new environments may be an important factor influencing Collembola invasions.

5.
Conserv Physiol ; 8(1): coaa049, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32577288

RESUMO

As global climates change, alien species are anticipated to have a growing advantage relative to their indigenous counterparts, mediated through consistent trait differences between the groups. These insights have largely been developed based on interspecific comparisons using multiple species examined from different locations. Whether such consistent physiological trait differences are present within assemblages is not well understood, especially for animals. Yet, it is at the assemblage level that interactions play out. Here, we examine whether physiological trait differences observed at the interspecific level are also applicable to assemblages. We focus on the Collembola, an important component of the soil fauna characterized by invasions globally, and five traits related to fitness: critical thermal maximum, minimum and range, desiccation resistance and egg development rate. We test the predictions that the alien component of a local assemblage has greater basal physiological tolerances or higher rates, and more pronounced phenotypic plasticity than the indigenous component. Basal critical thermal maximum, thermal tolerance range, desiccation resistance, optimum temperature for egg development, the rate of development at that optimum and the upper temperature limiting egg hatching success are all significantly higher, on average, for the alien than the indigenous components of the assemblage. Outcomes for critical thermal minimum are variable. No significant differences in phenotypic plasticity exist between the alien and indigenous components of the assemblage. These results are consistent with previous interspecific studies investigating basal thermal tolerance limits and development rates and their phenotypic plasticity, in arthropods, but are inconsistent with results from previous work on desiccation resistance. Thus, for the Collembola, the anticipated advantage of alien over indigenous species under warming and drying is likely to be manifest in local assemblages, globally.

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