title: Using Captain Scott's discovery specimens to unlock the past: has Antarctic cyanobacterial diversity changed over the last 100 years?

authors: Jungblut, Anne D.

subjects: Antarctica

abstract: Evidence of climate-driven environmental change is increasing in Antarctica, and with it comes concern that this will propagate to impacts on biological communities. Recognition and prediction of change needs to incorporate the extent and timescales over which communities vary under extant conditions. However, few observations of Antarctic microbial communities, which dominate inland habitats, allow this. We therefore carried out the first molecular comparison of Cyanobacteria in historic herbarium microbial mats from freshwater ecosystems on Ross Island and the McMurdo Ice Shelf, collected by Captain R.F. Scott's ‘Discovery’ Expedition (1902–1903), with modern samples from those areas. Using 16S rRNA gene surveys, we found that modern and historic cyanobacteria assemblages showed some variation in community structure but were dominated by the same genotypes. Modern communities had a higher richness, including genotypes not found in historic samples, but they had the highest similarity to other cyanobacteria sequences from Antarctica. The results imply slow cyanobacterial 16S rRNA gene genotype turnover and considerable community stability within Antarctic microbial mats. We suggest that this relates to Antarctic freshwater 'organisms requiring a capacity to withstand diverse stresses, and that this could also provide a degree of resistance and resilience to future climatic-driven environmental change in Antarctica.

text: Using Captain Scott's discovery specimens to unlock the past: has Antarctic cyanobacterial diversity changed over the last 100 years? Evidence of climate-driven environmental change is increasing in Antarctica, and with it comes concern that this will propagate to impacts on biological communities. Recognition and prediction of change needs to incorporate the extent and timescales over which communities vary under extant conditions. However, few observations of Antarctic microbial communities, which dominate inland habitats, allow this. We therefore carried out the first molecular comparison of Cyanobacteria in historic herbarium microbial mats from freshwater ecosystems on Ross Island and the McMurdo Ice Shelf, collected by Captain R.F. Scott's ‘Discovery’ Expedition (1902–1903), with modern samples from those areas. Using 16S rRNA gene surveys, we found that modern and historic cyanobacteria assemblages showed some variation in community structure but were dominated by the same genotypes. Modern communities had a higher richness, including genotypes not found in historic samples, but they had the highest similarity to other cyanobacteria sequences from Antarctica. The results imply slow cyanobacterial 16S rRNA gene genotype turnover and considerable community stability within Antarctic microbial mats. We suggest that this relates to Antarctic freshwater 'organisms requiring a capacity to withstand diverse stresses, and that this could also provide a degree of resistance and resilience to future climatic-driven environmental change in Antarctica.

year: 2017

title: Observations of nonlinear run-up patterns on plane and rhythmic beach morphology

authors: Bryan, Karin R.

subjects: nonlinear

abstract: Application of non-linear forecasting and bispectral analysis to video observations of run-up over cuspate topography shows that these alongshore patterns in the morphology are accompanied by changes to the fundamental behaviour of the run-up timeseries. Nonlinear forecasting indicates that at beach cusp horns, the behaviour of swash flow is more predictable and global (meaning that characteristics of individual swash events are well represented by the behaviour of the timeseries as a whole). Conversely, at beach cusp bays, the behaviour of swash flow is less predictable and more local (meaning that the characteristics of individual swash events are best represented by the behaviour of a small fraction of the timeseries). Bispectral analysis indicates that there is a nonlinear transfer of energy from the incident wave frequency f to infragravity frequency ~f/2 which only occurs in the bay, suggesting that the local behaviour is caused by interactions between successive swash cycles which are magnified by channelling caused by the beach cusp geometry. The local behaviour and the bispectral signatures are not present in offshore measurements, and are not present in runup timeseries collected when the beach was planar. These results provide evidence that interactions between successive run-ups are a fundamental characteristic of beach cusp bays. Ultimately, these interactions could lead to the growth of an infragravity wave with an alongshore wavelength forced by the presence of beach cusps.

text: Observations of nonlinear run-up patterns on plane and rhythmic beach morphology Application of non-linear forecasting and bispectral analysis to video observations of run-up over cuspate topography shows that these alongshore patterns in the morphology are accompanied by changes to the fundamental behaviour of the run-up timeseries. Nonlinear forecasting indicates that at beach cusp horns, the behaviour of swash flow is more predictable and global (meaning that characteristics of individual swash events are well represented by the behaviour of the timeseries as a whole). Conversely, at beach cusp bays, the behaviour of swash flow is less predictable and more local (meaning that the characteristics of individual swash events are best represented by the behaviour of a small fraction of the timeseries). Bispectral analysis indicates that there is a nonlinear transfer of energy from the incident wave frequency f to infragravity frequency ~f/2 which only occurs in the bay, suggesting that the local behaviour is caused by interactions between successive swash cycles which are magnified by channelling caused by the beach cusp geometry. The local behaviour and the bispectral signatures are not present in offshore measurements, and are not present in runup timeseries collected when the beach was planar. These results provide evidence that interactions between successive run-ups are a fundamental characteristic of beach cusp bays. Ultimately, these interactions could lead to the growth of an infragravity wave with an alongshore wavelength forced by the presence of beach cusps.

year: 2010

title: Rata, the Effect of Māori Land Law on Ahikāroa

authors: Whaanga, Mere Joslyn

subjects: Ahikāroa

abstract: Rata, the effect of Māori land law on ahikāroa is an examination of the special relationship a whānau of Ngāi Tahu (ki Wairoa) has had since 1868 with their ancestral land Tutuotekaha. The effects of Māori land law on traditional concepts of land tenure are analysed from the advent of the Native Land Court in the 1860s through to a modern shareholding in the Anewa Trust. An analysis of Te Ture Whenua Māori Act 1993 looks at the basis for the current legislation and how the principles are applied in the case study central to this thesis, an application to have Rata farm returned to the Whaanga whānau.

The research and writing is multi-disciplinary, combining history, Māori land law (ture) and Māori land lore (tikanga and traditional ecological knowledge). An auto-ethnographic approach is balanced by the commentary and judgements of the Māori Land Court and the Māori Appellate Court which are documented in the final section of the thesis.

This thesis questions the canons of Māori land ownership and management – consolidation, amalgamation and incorporation – and posits whether these forms of land holding have become yet another type of alienation.

The three main areas are
I) Ahikāroa
Chapters 2 and 3 examine traditional Māori land tenure; definitions of mana whenua, the obligations as well as the authority; and traditional ecological knowledge, agriculture and Māori land lore. The latter illustrates ways of knowing the land, how, why and when its resources were used. Members of the community of Iwitea were interviewed to provide accounts of usage of some of the traditional resources known to remain on the Tutuotekaha blocks.

II) From gardeners and gatherers to agricultural shareholders
Chapters 4, 5 and 6 examine the shift from traditional tenure and land usage to large-scale agricultural shareholdings. The changes as land passed through the Native Land Court from 1868 are contextualised within the upheaval and radical reconfiguring of Māori society in the Mahia and Wairoa areas as Pākehā settlement increased, and the region was engulfed by the Hauhau and Te Kooti conflicts. This section contains an overview of Māori land law from 1862 to 1987 and the ideological conflict between the colonisers and the colonised. As well, it looks at the influence of Sir James Carroll and Sir Āpirana Ngata, the reasons that Māori went into large-scale farming and how Ngata’s 1931 policies set the model for the incorporations and trusts that still hold most of the district’s Māori land today.

III) Te Ture Whenua Māori Act 1993, philosophy versus implementation
Chapters 7 through to 11 centre on Te Ture Whenua Māori Act 1993 and the application to the Māori Land Court to partition Rata farm from the Anewa Trust. The philosophy of the Act is examined, aided by Deputy Chief Judge Fox’s commentary. This section documents the processes of filing the application to partition, the discussions and outcomes of a judicial hearing, two Māori Land Court hearings and subsequent appeals to the Māori Appellate Court.

text: Rata, the Effect of Māori Land Law on Ahikāroa Rata, the effect of Māori land law on ahikāroa is an examination of the special relationship a whānau of Ngāi Tahu (ki Wairoa) has had since 1868 with their ancestral land Tutuotekaha. The effects of Māori land law on traditional concepts of land tenure are analysed from the advent of the Native Land Court in the 1860s through to a modern shareholding in the Anewa Trust. An analysis of Te Ture Whenua Māori Act 1993 looks at the basis for the current legislation and how the principles are applied in the case study central to this thesis, an application to have Rata farm returned to the Whaanga whānau.

The research and writing is multi-disciplinary, combining history, Māori land law (ture) and Māori land lore (tikanga and traditional ecological knowledge). An auto-ethnographic approach is balanced by the commentary and judgements of the Māori Land Court and the Māori Appellate Court which are documented in the final section of the thesis.

This thesis questions the canons of Māori land ownership and management – consolidation, amalgamation and incorporation – and posits whether these forms of land holding have become yet another type of alienation.

The three main areas are
I) Ahikāroa
Chapters 2 and 3 examine traditional Māori land tenure; definitions of mana whenua, the obligations as well as the authority; and traditional ecological knowledge, agriculture and Māori land lore. The latter illustrates ways of knowing the land, how, why and when its resources were used. Members of the community of Iwitea were interviewed to provide accounts of usage of some of the traditional resources known to remain on the Tutuotekaha blocks.

II) From gardeners and gatherers to agricultural shareholders
Chapters 4, 5 and 6 examine the shift from traditional tenure and land usage to large-scale agricultural shareholdings. The changes as land passed through the Native Land Court from 1868 are contextualised within the upheaval and radical reconfiguring of Māori society in the Mahia and Wairoa areas as Pākehā settlement increased, and the region was engulfed by the Hauhau and Te Kooti conflicts. This section contains an overview of Māori land law from 1862 to 1987 and the ideological conflict between the colonisers and the colonised. As well, it looks at the influence of Sir James Carroll and Sir Āpirana Ngata, the reasons that Māori went into large-scale farming and how Ngata’s 1931 policies set the model for the incorporations and trusts that still hold most of the district’s Māori land today.

III) Te Ture Whenua Māori Act 1993, philosophy versus implementation
Chapters 7 through to 11 centre on Te Ture Whenua Māori Act 1993 and the application to the Māori Land Court to partition Rata farm from the Anewa Trust. The philosophy of the Act is examined, aided by Deputy Chief Judge Fox’s commentary. This section documents the processes of filing the application to partition, the discussions and outcomes of a judicial hearing, two Māori Land Court hearings and subsequent appeals to the Māori Appellate Court.

year: 2012