Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Asunto de la revista
Intervalo de año de publicación
1.
Nature ; 583(7817): 567-571, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32669711

RESUMEN

Recent assessments of Earth's dwindling wilderness have emphasized that Antarctica is a crucial wilderness in need of protection1,2. Yet human impacts on the continent are widespread3-5, the extent of its wilderness unquantified2 and the importance thereof for biodiversity conservation unknown. Here we assemble a comprehensive record of human activity (approximately 2.7 million records, spanning 200 years) and use it to quantify the extent of Antarctica's wilderness and its representation of biodiversity. We show that 99.6% of the continent's area can still be considered wilderness, but this area captures few biodiversity features. Pristine areas, free from human interference, cover a much smaller area (less than 32% of Antarctica) and are declining as human activity escalates6. Urgent expansion of Antarctica's network of specially protected areas7 can both reverse this trend and secure the continent's biodiversity8-10.


Asunto(s)
Biodiversidad , Vida Silvestre , Animales , Regiones Antárticas , Conservación de los Recursos Naturales , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Actividades Humanas/historia
2.
Conserv Biol ; 36(4): e13885, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35040183

RESUMEN

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.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Animales , Regiones Antárticas , Ecosistema , Humanos , Líquenes , Plantas
3.
Proc Biol Sci ; 287(1940): 20202121, 2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33290676

RESUMEN

Terrestrial species on islands often show reduced dispersal abilities. For insects, the generality of explanations for island flight loss remains contentious. Although habitat stability is considered the most plausible explanation, others are frequently highlighted. Adopting a strong inference approach, we examined the hypotheses proposed to account for the prevalence of flightlessness in island insect assemblages, for a region long suspected to be globally unusual in this regard-the Southern Ocean Islands (SOIs). Combining comprehensive faunal inventories, species' morphological information, and environmental variables from 28 SOIs, we provide the first quantitative evidence that flightlessness is exceptionally prevalent among indigenous SOI insect species (47%). Prevalence among species which have evolved elsewhere is much lower: Arctic island species (8%), species introduced to the SOIs (17%), and globally (estimated as approx. 5%). Variation in numbers of flightless species and genera across islands is best explained by variation in wind speed, although habitat stability (thermal seasonality proxy) may play a role. Variables associated with insularity, such as island size, are generally poor predictors of flightlessness. The outcomes redirect attention to Darwin's wind hypothesis. They suggest, however, that wind selects for flightlessness through an energy trade-off between flight and reproduction, instead of by displacement from suitable habitats.


Asunto(s)
Vuelo Animal , Insectos , Islas , Viento , Animales
4.
J Anim Ecol ; 89(12): 2863-2875, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32981063

RESUMEN

Thermal performance traits are regularly used to make forecasts of the responses of ectotherms to anthropogenic environmental change, but such forecasts do not always differentiate between fundamental and realised thermal niches. Here we determine the relative extents to which variation in the fundamental and realised thermal niches accounts for current variation in species abundance and occupancy and assess the effects of niche-choice on future-climate response estimations. We investigated microclimate and macroclimate temperatures alongside abundance, occupancy, critical thermal limits and foraging activity of 52 ant species (accounting for >95% individuals collected) from a regional assemblage from across the Western Cape Province, South Africa, between 2003 and 2014. Capability of a species to occupy sites experiencing the most extreme temperatures, coupled with breadth of realised niche, explained most deviance in occupancy (up to 75%), while foraging temperature range and body mass explained up to 50.5% of observed variation in mean species abundance. When realised niches are used to forecast responses to climate change, large positive and negative effects among species are predicted under future conditions, in contrast to the forecasts of minimal impacts on all species that are indicated by fundamental niche predictions.


Asunto(s)
Cambio Climático , Ecosistema , Animales , Calor , Sudáfrica , Temperatura
5.
Sci Data ; 10(1): 200, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-37041141

RESUMEN

Open data on biological invasions are particularly critical in regions that are co-governed and/or where multiple independent parties have responsibility for preventing and controlling invasive alien species. The Antarctic is one such region where, in spite of multiple examples of invasion policy and management success, open, centralised data are not yet available. This dataset provides current and comprehensive information available on the identity, localities, establishment, eradication status, dates of introduction, habitat, and evidence of impact of known introduced and invasive alien species for the terrestrial and freshwater Antarctic and Southern Ocean region. It includes 3066 records for 1204 taxa and 36 individual localities. The evidence indicates that close to half of these species are not having an invasive impact, and that ~ 13% of records are of species considered locally invasive. The data are provided using current biodiversity and invasive alien species data and terminology standards. They provide a baseline for updating and maintaining the foundational knowledge needed to halt the rapidly growing risk of biological invasion in the region.


Asunto(s)
Biodiversidad , Especies Introducidas , Regiones Antárticas , Ecosistema , Océanos y Mares , Animales
6.
Sci Data ; 5: 180177, 2018 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-30179229

RESUMEN

Southern Ocean Islands are globally significant conservation areas. Predicting how their terrestrial ecosystems will respond to current and forecast climate change is essential for their management and requires high-quality temperature data at fine spatial resolutions. Existing datasets are inadequate for this purpose. Remote-sensed land surface temperature (LST) observations, such as those collected by satellite-mounted spectroradiometers, can provide high-resolution, spatially-continuous data for isolated locations. These methods require a clear sightline to measure surface conditions, however, which can leave large data-gaps in temperature time series. Using a spatio-temporal gap-filling method applied to high-resolution (~1 km) LST observations for 20 Southern Ocean Islands, we compiled a complete monthly temperature dataset for a 15-year period (2001-2015). We validated results using in situ measurements of microclimate temperature. Gap-filled temperature observations described the thermal heterogeneity of the region better than existing climatology datasets, particularly for islands with steep elevational gradients and strong prevailing winds. This dataset will be especially useful for terrestrial ecologists, conservation biologists, and for developing island-specific management and mitigation strategies for environmental change.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA