title: Survival of thermophilic spore-forming bacteria in a 90+ year old milk powder from Ernest Shackelton's Cape Royds Hut in Antarctica

authors: Ronimus, Ron S.

subjects: Bacillus licheniformis

abstract: Milk powder taken to Antarctica on Shackelton's British Antarctic Expedition in 1907 was produced in New Zealand by a roller drying process in the first factory in the world dedicated to this process. Thermophilic bacilli are the dominant contaminants of modern spray-dried milk powders and the 1907 milk powder allows a comparison to be made of contaminating strains in roller-dried and spray-dried powders. Samples of milk powder obtained from Shackelton's Hut at Cape Royds had low levels of thermophilic contamination (<500 cfu ml−1) but the two dominant strains (Bacillus licheniformis strain F and Bacillus subtilis) were typical of those found in spray-dried powders. Soil samples from the floor of the hut also contained these strains, whereas soils distant from the hut did not. Differences in the RAPD profiles of isolates from the milk powder and the soils suggest that contamination of the milk from the soil was unlikely. It is significant that the most commonly encountered contaminant strain in modern spray-dried milk (Anoxybacillus flavithermus strain C) was not detected in the 1907 sample.

text: Survival of thermophilic spore-forming bacteria in a 90+ year old milk powder from Ernest Shackelton's Cape Royds Hut in Antarctica Milk powder taken to Antarctica on Shackelton's British Antarctic Expedition in 1907 was produced in New Zealand by a roller drying process in the first factory in the world dedicated to this process. Thermophilic bacilli are the dominant contaminants of modern spray-dried milk powders and the 1907 milk powder allows a comparison to be made of contaminating strains in roller-dried and spray-dried powders. Samples of milk powder obtained from Shackelton's Hut at Cape Royds had low levels of thermophilic contamination (<500 cfu ml−1) but the two dominant strains (Bacillus licheniformis strain F and Bacillus subtilis) were typical of those found in spray-dried powders. Soil samples from the floor of the hut also contained these strains, whereas soils distant from the hut did not. Differences in the RAPD profiles of isolates from the milk powder and the soils suggest that contamination of the milk from the soil was unlikely. It is significant that the most commonly encountered contaminant strain in modern spray-dried milk (Anoxybacillus flavithermus strain C) was not detected in the 1907 sample.

year: 2000

title: Effects of anthropogenic land use on temperate mangrove forests

authors: Thomson, Timothy

subjects: Temperate mangrove forests

abstract: Coastal ecosystems worldwide are facing unprecedented challenges due to ever increasing human activities, resulting in increased land-derived stressors that can threaten the health and integrity of these systems. Mangrove forests are unique ecosystems that play a crucial role in filtering nutrients, retaining pollutants, and sequestering carbon. However, to what extent they are impacted by an intensification of human pressures is unclear and empirical evidence of landscape scale effects of a holistic view of the ecosystem is scarce. This thesis investigates the effects of human land use on several aspects of temperate mangrove ecosystems and aims to identify potential vulnerabilities of ecosystem processes to provide a holistic view on the impacts that humas are having on these important ecosystems.
By working across a broad gradient of human land use, the first chapter establishes a connection between human land use intensity in catchments and regionally generalizable trends in mangrove forest structure and physicochemical parameters in sediments. Highlighting the integrated nature of anthropogenic impacts, this chapter emphasizes the need for holistic evaluations in assessing responses of complex natural systems to change.
The second chapter investigates environmental controls on organic matter degradation in mangrove forests. Results from this study emphasize the importance of considering multiple factors influencing degradation processes, that vary with the quality of the decaying organic matter. Furthermore, using the human land use gradient from the previous chapter, this study identifies an impact of human land use through eutrophication on the rate of labile organic matter loss from mangrove sediments.
The third chapter provides insights into bacterial communities in temperate mangrove sediments, revealing the persistent effects of nutrient enrichment even after the biochemical signal is lost. The study highlights the spatial resolution needed to detect impacts on microbial communities, warning that functional changes may persist beyond observable eutrophication effects.

The synthesis of these chapters provides a holistic view of the effects of anthropogenic impacts on temperate mangrove ecosystems across various scales. While some components of the system may benefit from moderate amounts of nutrient enrichment, others can deteriorate, ultimately diminishing overall service provisioning of the system. To understand and quantify these effects, this thesis calls for a nuanced understanding of disturbance effects on mangrove ecosystems, emphasizing their complexity and the interconnectedness of their components. It adds a valuable information about the functional resilience of mangrove forests in the face of human pressures and highlights the importance of an ecosystem-based perspective when assessing the effects of external stressors on these important ecosystems.

text: Effects of anthropogenic land use on temperate mangrove forests Coastal ecosystems worldwide are facing unprecedented challenges due to ever increasing human activities, resulting in increased land-derived stressors that can threaten the health and integrity of these systems. Mangrove forests are unique ecosystems that play a crucial role in filtering nutrients, retaining pollutants, and sequestering carbon. However, to what extent they are impacted by an intensification of human pressures is unclear and empirical evidence of landscape scale effects of a holistic view of the ecosystem is scarce. This thesis investigates the effects of human land use on several aspects of temperate mangrove ecosystems and aims to identify potential vulnerabilities of ecosystem processes to provide a holistic view on the impacts that humas are having on these important ecosystems.
By working across a broad gradient of human land use, the first chapter establishes a connection between human land use intensity in catchments and regionally generalizable trends in mangrove forest structure and physicochemical parameters in sediments. Highlighting the integrated nature of anthropogenic impacts, this chapter emphasizes the need for holistic evaluations in assessing responses of complex natural systems to change.
The second chapter investigates environmental controls on organic matter degradation in mangrove forests. Results from this study emphasize the importance of considering multiple factors influencing degradation processes, that vary with the quality of the decaying organic matter. Furthermore, using the human land use gradient from the previous chapter, this study identifies an impact of human land use through eutrophication on the rate of labile organic matter loss from mangrove sediments.
The third chapter provides insights into bacterial communities in temperate mangrove sediments, revealing the persistent effects of nutrient enrichment even after the biochemical signal is lost. The study highlights the spatial resolution needed to detect impacts on microbial communities, warning that functional changes may persist beyond observable eutrophication effects.

The synthesis of these chapters provides a holistic view of the effects of anthropogenic impacts on temperate mangrove ecosystems across various scales. While some components of the system may benefit from moderate amounts of nutrient enrichment, others can deteriorate, ultimately diminishing overall service provisioning of the system. To understand and quantify these effects, this thesis calls for a nuanced understanding of disturbance effects on mangrove ecosystems, emphasizing their complexity and the interconnectedness of their components. It adds a valuable information about the functional resilience of mangrove forests in the face of human pressures and highlights the importance of an ecosystem-based perspective when assessing the effects of external stressors on these important ecosystems.

year: 2024

title: Modelling loanword success a sociolinguistic quantitative study of Māori loanwords in New Zealand English

authors: Calude, Andreea S.

subjects: loanwords

abstract: Loanword use has dominated the literature on language contact and its salient nature continues to draw interest from linguists and non-linguists. Traditionally, loanwords were investigated by means of raw frequencies, which are at best uninformative and at worst misleading. Following a new wave of studies which look at loans from a quantitatively more informed standpoint, modelling “success” by taking into account frequency of the counterparts avail- able in the language adopting the loanwords, we propose a similar model of loan-use and demonstrate its benefits in a case study of loanwords from Māori into (New Zealand) English. Our model contributes to previous work in this area by combining both the success measure mentioned above with a rich range of linguistic characteristics of the loanwords (such as loan length and word class), as well as a similarly detailed group of sociolinguistic characteristics of the speakers using them (gender, age and ethnicity of both, speakers and addresses). Our model is unique in bringing together of all these factors at the same time. The findings presented here illustrate the benefit of a quantitatively balanced approach to modelling loanword use. Furthermore, they illustrate the complex interaction between linguistic and sociolinguistic factors in such lan- guage contact scenarios.

text: Modelling loanword success a sociolinguistic quantitative study of Māori loanwords in New Zealand English Loanword use has dominated the literature on language contact and its salient nature continues to draw interest from linguists and non-linguists. Traditionally, loanwords were investigated by means of raw frequencies, which are at best uninformative and at worst misleading. Following a new wave of studies which look at loans from a quantitatively more informed standpoint, modelling “success” by taking into account frequency of the counterparts avail- able in the language adopting the loanwords, we propose a similar model of loan-use and demonstrate its benefits in a case study of loanwords from Māori into (New Zealand) English. Our model contributes to previous work in this area by combining both the success measure mentioned above with a rich range of linguistic characteristics of the loanwords (such as loan length and word class), as well as a similarly detailed group of sociolinguistic characteristics of the speakers using them (gender, age and ethnicity of both, speakers and addresses). Our model is unique in bringing together of all these factors at the same time. The findings presented here illustrate the benefit of a quantitatively balanced approach to modelling loanword use. Furthermore, they illustrate the complex interaction between linguistic and sociolinguistic factors in such lan- guage contact scenarios.

year: 2017