title: Microbial abundance and diversity surrounding mummified seals in Miers Valley, Antarctica

authors: Robson, Lisa Marie

subjects: Dry Valleys

abstract: The presence of a number of mummified seal carcasses have been reported in the Dry Valleys of Antarctica. The location of seal carcasses were observed up to 240km in-land, and approximately 1500m above sea level. The extremely cold and dry conditions in the Dry Valleys act to mummify the seal remams, preserving these anomalies for an undetermined length of time.
Given the virtual absence of above ground plant biomass in the Dry Valleys, the primary source of soil organic matter sustaining microbial ecosystems was not obvious. It was hypothesised that these large sources of organic contamination, in the form of a seal carcass, may act to enrich the localised environment surrounding the carcasses with carbon and nitrogen. The increased levels of organic carbon and nitrogen would result in increased microbial abundance and diversity.
A total of 100 environmental samples were taken by Professors S.C. Cary, and D.A. Cowan, surrounding, and directly beneath eleven mummified seals located in Miers Valley, the Antarctic Dry Valleys, on Event D023 Terrestrial Microbiology Antarctic New Zealand 2001/2002. Three of these seals (MVSl, MVS3 and MVS 13) and the areas surrounding, were sampled extensively, and were the basis of research in this Master of Science thesis.
Microbial diversity was investigated using molecular cloning and sequence analysis, and Denaturing Gradient Gel Electrophoresis, of 16S and 18S rDNA amplicons. A large diversity in bacterial populations present in the environmental samples taken from directly beneath the Miers Valley seal carcasses was observed in comparison to control samples of Miers Valley soils.
The levels of microbial abundance were determined by luciferase-dependent luminometric ATP analysis, and analysis of the total quantities of double stranded DNA extracted from the environmental samples. Microbial abundance was found to be increased in samples taken in closer proximity to a seal carcass.
Carbon and nitrogen analysis were conducted on all samples, using a fully automated Europa Scientific 20/20 isotope analyser. The level of carbon present in an environmental sample appeared not to influence the abundance of microorganisms. The levels of nitrogen measured were higher in environmental samples collected in close proximity to the seal carcasses. These samples displayed the greatest microbial abundance, and indicated large differences in the bacterial diversity compared to Miers Valley control samples.
On the basis of these results, and ATP data, the hypothesis of this MSc thesis was determined to be correct. Microbial abundance was found to increase with enrichment of nitrogen surrounding MVS 1 and MVS 13 seal carcasses, and large differences in bacterial diversity were found in environmental samples showing the highest levels of nitrogen enrichment, compared to samples taken further away from the seal, or in Miers Valley control samples.
This thesis effectively described the utilisation of cloning and sequence analysis, and denaturing gradient gel electrophoresis to investigate microbial diversity in Antarctic environmental samples. This study gave a greater understanding in microbial ecology in Miers Valley, Antarctica.

text: Microbial abundance and diversity surrounding mummified seals in Miers Valley, Antarctica The presence of a number of mummified seal carcasses have been reported in the Dry Valleys of Antarctica. The location of seal carcasses were observed up to 240km in-land, and approximately 1500m above sea level. The extremely cold and dry conditions in the Dry Valleys act to mummify the seal remams, preserving these anomalies for an undetermined length of time.
Given the virtual absence of above ground plant biomass in the Dry Valleys, the primary source of soil organic matter sustaining microbial ecosystems was not obvious. It was hypothesised that these large sources of organic contamination, in the form of a seal carcass, may act to enrich the localised environment surrounding the carcasses with carbon and nitrogen. The increased levels of organic carbon and nitrogen would result in increased microbial abundance and diversity.
A total of 100 environmental samples were taken by Professors S.C. Cary, and D.A. Cowan, surrounding, and directly beneath eleven mummified seals located in Miers Valley, the Antarctic Dry Valleys, on Event D023 Terrestrial Microbiology Antarctic New Zealand 2001/2002. Three of these seals (MVSl, MVS3 and MVS 13) and the areas surrounding, were sampled extensively, and were the basis of research in this Master of Science thesis.
Microbial diversity was investigated using molecular cloning and sequence analysis, and Denaturing Gradient Gel Electrophoresis, of 16S and 18S rDNA amplicons. A large diversity in bacterial populations present in the environmental samples taken from directly beneath the Miers Valley seal carcasses was observed in comparison to control samples of Miers Valley soils.
The levels of microbial abundance were determined by luciferase-dependent luminometric ATP analysis, and analysis of the total quantities of double stranded DNA extracted from the environmental samples. Microbial abundance was found to be increased in samples taken in closer proximity to a seal carcass.
Carbon and nitrogen analysis were conducted on all samples, using a fully automated Europa Scientific 20/20 isotope analyser. The level of carbon present in an environmental sample appeared not to influence the abundance of microorganisms. The levels of nitrogen measured were higher in environmental samples collected in close proximity to the seal carcasses. These samples displayed the greatest microbial abundance, and indicated large differences in the bacterial diversity compared to Miers Valley control samples.
On the basis of these results, and ATP data, the hypothesis of this MSc thesis was determined to be correct. Microbial abundance was found to increase with enrichment of nitrogen surrounding MVS 1 and MVS 13 seal carcasses, and large differences in bacterial diversity were found in environmental samples showing the highest levels of nitrogen enrichment, compared to samples taken further away from the seal, or in Miers Valley control samples.
This thesis effectively described the utilisation of cloning and sequence analysis, and denaturing gradient gel electrophoresis to investigate microbial diversity in Antarctic environmental samples. This study gave a greater understanding in microbial ecology in Miers Valley, Antarctica.

year: 2004

title: A new look at population change and regional development in Aotearoa New Zealand

authors: Brabyn, Lars

subjects: Demography

abstract: In New Zealand, population change is interlinked with regional development. Places growing in population attract regional investment, while regional investment—or lack thereof—can change migration patterns. However, to determine the appropriate response to population change for a community, it is important to understand that population change involves much more than “just” migration. Specifically, it involves interactions between the three components of population change: natural change (births minus deaths), net migration (international and internal) and population ageing (changing cohort size). For example, migration can be negative, but growth can be positive due to underlying natural increase or growth in cohort size. Responses need to differ, depending on these drivers. The goal of this article is to provide new insights into these interactions using data for 275 cities, towns and rural centres (hereafter “urban places”) in New Zealand for the period 1976 to 2013. The results show that natural change has been consistently positive for most urban places up to the present, although projections indicate that in the future this component will become negative across much of the country. At the same time, net migration shows considerable spatial variation, not only in terms of volume, but also direction (negative or positive), which differs markedly by age. A net gain of people of retirement age can offset a net loss of young adults to deliver overall growth, and vice-versa, but the two have very different implications for longer term growth. An analysis of the drivers of net migration using GIS and machine learning techniques provides an indication of the importance of economic conditions (land-use and access to markets), lifestyle, access to essential services (hospitals and education) and their interaction with age in regional change. The results show that population age is the best predictor of migration. Younger people are moving to cities for tertiary education and work and older people near or in retirement are moving to smaller lifestyle towns but also want to be close to amenities such as hospitals and international airports. The research also shows that natural lifestyle characteristics (landscape and climate), in combination with age are just as important as economic conditions for understanding migration. Regional development, such as infrastructure that helps business (ports and services) is important for the working age population but not necessarily the retirement age group. When regional development, age/life-cycle stage and lifestyle come together, such as in Queenstown and Tauranga, net migration gain is high.

text: A new look at population change and regional development in Aotearoa New Zealand In New Zealand, population change is interlinked with regional development. Places growing in population attract regional investment, while regional investment—or lack thereof—can change migration patterns. However, to determine the appropriate response to population change for a community, it is important to understand that population change involves much more than “just” migration. Specifically, it involves interactions between the three components of population change: natural change (births minus deaths), net migration (international and internal) and population ageing (changing cohort size). For example, migration can be negative, but growth can be positive due to underlying natural increase or growth in cohort size. Responses need to differ, depending on these drivers. The goal of this article is to provide new insights into these interactions using data for 275 cities, towns and rural centres (hereafter “urban places”) in New Zealand for the period 1976 to 2013. The results show that natural change has been consistently positive for most urban places up to the present, although projections indicate that in the future this component will become negative across much of the country. At the same time, net migration shows considerable spatial variation, not only in terms of volume, but also direction (negative or positive), which differs markedly by age. A net gain of people of retirement age can offset a net loss of young adults to deliver overall growth, and vice-versa, but the two have very different implications for longer term growth. An analysis of the drivers of net migration using GIS and machine learning techniques provides an indication of the importance of economic conditions (land-use and access to markets), lifestyle, access to essential services (hospitals and education) and their interaction with age in regional change. The results show that population age is the best predictor of migration. Younger people are moving to cities for tertiary education and work and older people near or in retirement are moving to smaller lifestyle towns but also want to be close to amenities such as hospitals and international airports. The research also shows that natural lifestyle characteristics (landscape and climate), in combination with age are just as important as economic conditions for understanding migration. Regional development, such as infrastructure that helps business (ports and services) is important for the working age population but not necessarily the retirement age group. When regional development, age/life-cycle stage and lifestyle come together, such as in Queenstown and Tauranga, net migration gain is high.

year: 2019

title: Pushing the process: A whānau journey through the Treaty of Waitangi claims process

authors: Harrison, Reece David

subjects: Whanau Claims

abstract: This thesis follows the journey of a Whānau (ngā uri a Arama Whakatau) in its Claim to the Waitangi Tribunal under the Treaty of Waitangi Act 1986. In particular, it looks at inter-Whānau dynamics before, during and after the Claims process. The connections to the claimant area through whakapapa and establishing ahi kaa rights are identified, as are problems faced by lodging a Claim at the Whānau level. Aspects of inter-Whānau, inter-Hapū and inter-iwi politics are considered along with Crown agencies' processes. The primary question posed in the thesis is whether a Whānau Claim is the more appropriate avenue compared to making a Claim through the Hapū or iwi. However, the inter-Whānau dynamics are the core focus of the thesis in this 'warts-and-all' discussion from the perspective of the participant-observer.

text: Pushing the process: A whānau journey through the Treaty of Waitangi claims process This thesis follows the journey of a Whānau (ngā uri a Arama Whakatau) in its Claim to the Waitangi Tribunal under the Treaty of Waitangi Act 1986. In particular, it looks at inter-Whānau dynamics before, during and after the Claims process. The connections to the claimant area through whakapapa and establishing ahi kaa rights are identified, as are problems faced by lodging a Claim at the Whānau level. Aspects of inter-Whānau, inter-Hapū and inter-iwi politics are considered along with Crown agencies' processes. The primary question posed in the thesis is whether a Whānau Claim is the more appropriate avenue compared to making a Claim through the Hapū or iwi. However, the inter-Whānau dynamics are the core focus of the thesis in this 'warts-and-all' discussion from the perspective of the participant-observer.

year: 2007