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1.
PhytoKeys ; (39): 35-48, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25197224

RESUMEN

The Hawaiian endemic Viola kauaensis A. Gray has a broad distribution in bogs of Kaua`i and a limited distribution on mesic ridges in the Ko`olau Mountains of O`ahu. Based on differences in scale, the O`ahu populations of Viola kauaensis had previously been described as a distinct taxon. The taxonomic status of the O`ahu populations was reevaluated through a morphometric analysis of all varieties of Viola kauaensis and the morphologically similar Viola vanroyenii. Morphological features of historic and freshly collected specimens of all varieties of Viola kauaensis were analyzed with a principal components analysis. Populations from O`ahu represent a distinct cluster that slightly overlaps with Viola kauaensis var. kauaensis. Lamina width, apex angle, and base angles contribute to the separation of the O`ahu populations from other varieties of Viola kauaensis. Due to differences in scale, the O`ahu populations are described as Viola kauaensis var. hosakae, a new critically endangered taxon.

2.
J Air Waste Manag Assoc ; 61(4): 390-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21516934

RESUMEN

Epidemiological studies of exposure to vegetation fire smoke are often limited by the availability of accurate exposure data. This paper describes a systematic framework for retrospectively identifying the cause of air pollution events to facilitate a long, multicenter analysis of the public health effects of vegetation fire smoke pollution in Australia. Pollution events were statistically defined as any day at or above the 95th percentile of the 24-hr average concentration of particulate matter (PM). These were identified for six cities from three distinct ecoclimatic regions of Australia. The dates of each event were then crosschecked against a range of information sources, including online newspaper archives, government and research agency records, satellite imagery, and aerosol optical thickness measures to identify the cause for the excess particulate pollution. Pollution events occurred most frequently during summer for cities in subtropical and arid regions and during winter for cities in temperate regions. A cause for high PM on 67% of days examined in the city of Sydney was found, and 94% of these could be attributed to landscape fire smoke. Results were similar for cities in other subtropical and arid locations. Identification of the cause of pollution events was much lower in colder temperate regions where fire activity is less frequent. Bushfires were the most frequent cause of extreme pollution events in cities located in subtropical and arid regions of Australia. Although identification of pollution episodes was greatly improved by the use of multiple sources of information, satellite imagery was the most useful tool for identifying bushfire smoke pollution events.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Contaminantes Ocupacionales del Aire/historia , Contaminación del Aire/análisis , Contaminación del Aire/historia , Ciudades , Material Particulado/análisis , Australia , Bases de Datos Factuales , Polvo/análisis , Incendios , Historia del Siglo XX , Historia del Siglo XXI , Oxidantes Fotoquímicos/análisis , Ozono/análisis , Comunicaciones por Satélite , Humo
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