title: Application of flow cytometry for examining phytoplankton succession in two eutrophic lakes

authors: Dennis, Marie

subjects: Cyanophyta

abstract: Flow cytometry has potential as a rapid assessment technique to evaluate phytoplankton biomass and species composition. It facilitates for multi-parameter analysis of individual cells on the basis of light scattering effects induced from cellular constituents, as well as auto-fluorescence. Fluorescence emission characteristics may be especially useful in classifying cyanobacteria as they contain phycoerythrin which emits light predominantly in the 550–600 nm waveband, chlorophyll-a (650–700 nm emission) and allophycocyanin (660 nm emission). The objective of our study was to assess the utility of flow cytometry for the rapid identification and sorting of freshwater algae and cyanobacteria species. Using a selection of laboratory-cultured freshwater algae and cyanobacteria species, this study demonstrated unique light scatter and fluorescent characteristics for each species examined, allowing for rapid species identification and sorting of mixed populations of laboratory cultures and samples from two lakes in the Rotorua region (New Zealand). Analysis of lake water samples collected over seven months demonstrated changes in abundance and community composition of phytoplankton in the two lakes and demonstrates that flow cytometry may be a useful technique for examining seasonal changes in phytoplankton composition.

text: Application of flow cytometry for examining phytoplankton succession in two eutrophic lakes Flow cytometry has potential as a rapid assessment technique to evaluate phytoplankton biomass and species composition. It facilitates for multi-parameter analysis of individual cells on the basis of light scattering effects induced from cellular constituents, as well as auto-fluorescence. Fluorescence emission characteristics may be especially useful in classifying cyanobacteria as they contain phycoerythrin which emits light predominantly in the 550–600 nm waveband, chlorophyll-a (650–700 nm emission) and allophycocyanin (660 nm emission). The objective of our study was to assess the utility of flow cytometry for the rapid identification and sorting of freshwater algae and cyanobacteria species. Using a selection of laboratory-cultured freshwater algae and cyanobacteria species, this study demonstrated unique light scatter and fluorescent characteristics for each species examined, allowing for rapid species identification and sorting of mixed populations of laboratory cultures and samples from two lakes in the Rotorua region (New Zealand). Analysis of lake water samples collected over seven months demonstrated changes in abundance and community composition of phytoplankton in the two lakes and demonstrates that flow cytometry may be a useful technique for examining seasonal changes in phytoplankton composition.

year: 2011

title: Insights on the environmental impacts associated with visible disturbance of ice-free ground in Antarctica

authors: Brooks, Shaun T.

subjects: Science & Technology

abstract: The small ice-free areas of Antarctica provide an essential habitat for most evident terrestrial biodiversity, as well as being disproportionately targeted by human activity. Visual detection of disturbance within these environments has become a useful tool for measuring areas affected by human impact, but questions remain as to what environmental consequences such disturbance actually has. To answer such questions, several factors must be considered, including the climate and biotic and abiotic characteristics. Although a body of research has established the consequences of disturbance at given locations, this paper was conceived in order to assess whether their findings could be generalized as a statement across the Antarctic continent. From a review of 31 studies within the Maritime Antarctic, Continental Antarctic and McMurdo Dry Valleys regions, we found that 83% confirmed impacts in areas of visible disturbance. Disturbance was found to modify the physical environment, consequently reducing habitat suitability as well as directly damaging biota. Visible disturbance was also associated with hydrocarbon and heavy metal contamination and non-native species establishment, reflecting the pressures from human activity in these sites. The results add significance to existing footprint measurements based on visual analysis, should aid on-the-ground appreciation of probable impacts in sites of disturbance and benefit environmental assessment processes.

text: Insights on the environmental impacts associated with visible disturbance of ice-free ground in Antarctica The small ice-free areas of Antarctica provide an essential habitat for most evident terrestrial biodiversity, as well as being disproportionately targeted by human activity. Visual detection of disturbance within these environments has become a useful tool for measuring areas affected by human impact, but questions remain as to what environmental consequences such disturbance actually has. To answer such questions, several factors must be considered, including the climate and biotic and abiotic characteristics. Although a body of research has established the consequences of disturbance at given locations, this paper was conceived in order to assess whether their findings could be generalized as a statement across the Antarctic continent. From a review of 31 studies within the Maritime Antarctic, Continental Antarctic and McMurdo Dry Valleys regions, we found that 83% confirmed impacts in areas of visible disturbance. Disturbance was found to modify the physical environment, consequently reducing habitat suitability as well as directly damaging biota. Visible disturbance was also associated with hydrocarbon and heavy metal contamination and non-native species establishment, reflecting the pressures from human activity in these sites. The results add significance to existing footprint measurements based on visual analysis, should aid on-the-ground appreciation of probable impacts in sites of disturbance and benefit environmental assessment processes.

year: 2019

title: Help or hindrance? New Zealand audience perspectives on subtitled media

authors: Kirk, Victoria

abstract: This research presents a picture of audiences’ patterns of engagement with internationally subtitled media in Hamilton, New Zealand. Utilising an audience reception framework to investigate audiences’ interactions with, and evaluations of subtitled media, this research unites the disciplines of Audio Visual Translation and Screen and Media Studies in a specific locale, with an emphasis on the reception of audio visual translated media. Findings in this research also provide a discussion of the wider contexts of audience reception in New Zealand, by investigating local subtitled media in relation to media accessibility processes found in the distinctive cultural landscape of New Zealand. Ultimately, this research finds the situation in New Zealand regarding audiences and the reception of both local English and Māori language media, as well as international subtitled media, exhibits complex polarisations in both the local translation industry production and audience attitudes towards bilingual media. In contrast to this, is the proliferation of international media with subtitles, which is appreciated by Hamilton residents since it provides diverse, accessible, and enjoyable content through a variety of media platforms.

text: Help or hindrance? New Zealand audience perspectives on subtitled media This research presents a picture of audiences’ patterns of engagement with internationally subtitled media in Hamilton, New Zealand. Utilising an audience reception framework to investigate audiences’ interactions with, and evaluations of subtitled media, this research unites the disciplines of Audio Visual Translation and Screen and Media Studies in a specific locale, with an emphasis on the reception of audio visual translated media. Findings in this research also provide a discussion of the wider contexts of audience reception in New Zealand, by investigating local subtitled media in relation to media accessibility processes found in the distinctive cultural landscape of New Zealand. Ultimately, this research finds the situation in New Zealand regarding audiences and the reception of both local English and Māori language media, as well as international subtitled media, exhibits complex polarisations in both the local translation industry production and audience attitudes towards bilingual media. In contrast to this, is the proliferation of international media with subtitles, which is appreciated by Hamilton residents since it provides diverse, accessible, and enjoyable content through a variety of media platforms.

year: 2019