title: The ecological implications of reconstructed historic hydrodynamic conditions in Tauranga Harbour (1852-2006).

authors: Moffatt, Ariana

subjects: Tauranga Harbour

abstract: In order to manage, restore and mitigate the increasing anthropogenic impacts on estuarine systems in the future, it is useful to understand the magnitude and distribution of historic changes in environmental conditions that may have impacted on ecosystems through time. The general aim of this thesis is to hind cast historic environmental conditions in order to investigate the ecological implications of changes in geomorphology and hydrodynamics within the southern basin of Tauranga Harbour. This was achieved by compiling 11 bathymetries and developing a hydrodynamic numerical model. 
The bathymetries produced were from 1852, 1879, 1901, 1927, 1954 and 2006 (entrance adjusted bathymetries). An additional 5 bathymetries from 1852, 1879, 1901, 1927 and 1954 were compiled which had sediment removed from the intertidal areas to simulate infilling (intertidal adjusted bathymetries). The impact of the simulated infilling on depth Investigate the by comparing the entrance adjusted bathymetries with the intertidal adjusted bathymetries of each year. Using the numerical modelling environment Delft3D a numerical model of the southern basin of Tauranga harbour was developed to simulate historical hydrodynamic conditions for each of the 11 bathymetries. The impact of the simulated infilling on hydrodynamics was investigated by comparing the results of the entrance adjusted and intertidal adjusted numerical models of each year. The modelled hydrodynamic conditions of current speed, water level range and tracer decay from the intertidal adjusted bathymetries were used to investigate temporal changes in environmental conditions that may have influenced historic ecological health and distribution of species. 
The comparison of depth and hydrodynamics between the entrance and intertidal bathymetries for each year showed that the simulated infilling caused slight changes in the distribution of depth and a slight increase in the magnitude of current speed, water level range and rate of tracer decay. 
The temporal changes in the environmental conditions included large magnitude small scale changes in depth and current speed occurred in the harbour entrance channels. Water level had the most significant change prior to dredging across the Harbour potentially due to historic changes in the inlet cross-section. For depth, water level and current speed the 2006 conditions were most different to the earliest 1852 conditions. This is due to the accumulation of both large natural changes in geomorphology and hydrodynamics and changes from the anthropogenic dredging and development. The tracer decay had most difference through time in the regions with changes in the constricted entrance such as in the estuaries above Sulphur Point.
Significant ecological implications include changes in depth and water level influencing functions such as bivalve feeding times, inundation of mangroves and light attenuation for seagrass. A significant change through time as a result of the intertidal infilling is the predicted expansion of mangroves. Differences in current speeds would alter the distribution of sediment and species as well as the settlement of larvae. Residence times have had largescale changes due to the anthropogenic changes around port development. These changes would result in an increase in the retention of sediments, contaminants and larvae and a shift from bivalve dominance to polychaete’s as well as altered community connectivity.

text: The ecological implications of reconstructed historic hydrodynamic conditions in Tauranga Harbour (1852-2006). In order to manage, restore and mitigate the increasing anthropogenic impacts on estuarine systems in the future, it is useful to understand the magnitude and distribution of historic changes in environmental conditions that may have impacted on ecosystems through time. The general aim of this thesis is to hind cast historic environmental conditions in order to investigate the ecological implications of changes in geomorphology and hydrodynamics within the southern basin of Tauranga Harbour. This was achieved by compiling 11 bathymetries and developing a hydrodynamic numerical model. 
The bathymetries produced were from 1852, 1879, 1901, 1927, 1954 and 2006 (entrance adjusted bathymetries). An additional 5 bathymetries from 1852, 1879, 1901, 1927 and 1954 were compiled which had sediment removed from the intertidal areas to simulate infilling (intertidal adjusted bathymetries). The impact of the simulated infilling on depth Investigate the by comparing the entrance adjusted bathymetries with the intertidal adjusted bathymetries of each year. Using the numerical modelling environment Delft3D a numerical model of the southern basin of Tauranga harbour was developed to simulate historical hydrodynamic conditions for each of the 11 bathymetries. The impact of the simulated infilling on hydrodynamics was investigated by comparing the results of the entrance adjusted and intertidal adjusted numerical models of each year. The modelled hydrodynamic conditions of current speed, water level range and tracer decay from the intertidal adjusted bathymetries were used to investigate temporal changes in environmental conditions that may have influenced historic ecological health and distribution of species. 
The comparison of depth and hydrodynamics between the entrance and intertidal bathymetries for each year showed that the simulated infilling caused slight changes in the distribution of depth and a slight increase in the magnitude of current speed, water level range and rate of tracer decay. 
The temporal changes in the environmental conditions included large magnitude small scale changes in depth and current speed occurred in the harbour entrance channels. Water level had the most significant change prior to dredging across the Harbour potentially due to historic changes in the inlet cross-section. For depth, water level and current speed the 2006 conditions were most different to the earliest 1852 conditions. This is due to the accumulation of both large natural changes in geomorphology and hydrodynamics and changes from the anthropogenic dredging and development. The tracer decay had most difference through time in the regions with changes in the constricted entrance such as in the estuaries above Sulphur Point.
Significant ecological implications include changes in depth and water level influencing functions such as bivalve feeding times, inundation of mangroves and light attenuation for seagrass. A significant change through time as a result of the intertidal infilling is the predicted expansion of mangroves. Differences in current speeds would alter the distribution of sediment and species as well as the settlement of larvae. Residence times have had largescale changes due to the anthropogenic changes around port development. These changes would result in an increase in the retention of sediments, contaminants and larvae and a shift from bivalve dominance to polychaete’s as well as altered community connectivity.

year: 2021

title: A new intrinsic thermal parameter for enzymes reveals true temperature optima

authors: Peterson, Michelle E.

subjects: enzyme

abstract: Two established thermal properties of enzymes are the Arrhenius activation energy and thermal stability. Arising from anomalies found in the variation of enzyme activity with temperature, a comparison has been made of experimental data for the activity and stability properties of five different enzymes with theoretical models. The results provide evidence for a new and fundamental third thermal parameter of enzymes, Teq, arising from a subsecond timescale-reversible temperature-dependent equilibrium between the active enzyme and an inactive (or less active) form. Thus, at temperatures above its optimum, the decrease in enzyme activity arising from the temperature-dependent shift in this equilibrium is up to two orders of magnitude greater than what occurs through thermal denaturation. This parameter has important implications for our understanding of the connection between catalytic activity and thermostability and of the effect of temperature on enzyme reactions within the cell. Unlike the Arrhenius activation energy, which is unaffected by the source (“evolved”) temperature of the enzyme, and enzyme stability, which is not necessarily related to activity, Teq is central to the physiological adaptation of an enzyme to its environmental temperature and links the molecular, physiological, and environmental aspects of the adaptation of life to temperature in a way that has not been described previously. We may therefore expect the effect of evolution on Teq with respect to enzyme temperature/activity effects to be more important than on thermal stability. Teq is also an important parameter to consider when engineering enzymes to modify their thermal properties by both rational design and by directed enzyme evolution.

text: A new intrinsic thermal parameter for enzymes reveals true temperature optima Two established thermal properties of enzymes are the Arrhenius activation energy and thermal stability. Arising from anomalies found in the variation of enzyme activity with temperature, a comparison has been made of experimental data for the activity and stability properties of five different enzymes with theoretical models. The results provide evidence for a new and fundamental third thermal parameter of enzymes, Teq, arising from a subsecond timescale-reversible temperature-dependent equilibrium between the active enzyme and an inactive (or less active) form. Thus, at temperatures above its optimum, the decrease in enzyme activity arising from the temperature-dependent shift in this equilibrium is up to two orders of magnitude greater than what occurs through thermal denaturation. This parameter has important implications for our understanding of the connection between catalytic activity and thermostability and of the effect of temperature on enzyme reactions within the cell. Unlike the Arrhenius activation energy, which is unaffected by the source (“evolved”) temperature of the enzyme, and enzyme stability, which is not necessarily related to activity, Teq is central to the physiological adaptation of an enzyme to its environmental temperature and links the molecular, physiological, and environmental aspects of the adaptation of life to temperature in a way that has not been described previously. We may therefore expect the effect of evolution on Teq with respect to enzyme temperature/activity effects to be more important than on thermal stability. Teq is also an important parameter to consider when engineering enzymes to modify their thermal properties by both rational design and by directed enzyme evolution.

year: 2004

title: Te manemanerau a te kāwanatanga: A history of the confiscation of Tūhoe lands in the Bay of Plenty

authors: Melbourne, Sydney

subjects: Ngāi Tūhoe

abstract: This thesis endeavours to show that Tūhoe lands should never have been confiscated and that Tūhoe efforts to gain compensation have been totally unsuccessful to date. When certain lands within the confiscated district of the Bay of Plenty were returned to the tribes there, Tūhoe were not granted any. Furthermore, lands which actually belonged to Tūhoe were granted to other tribes.
Although the major focus is on issues specific to Tūhoe, these are viewed within the wider context of nineteenth century land acquisition in New Zealand. This study looks at Tūhoe historical claims to disputed lands included in the confiscation district of the Bay of Plenty. Chapter One traces the extent of Tūhoe territories within the confiscation district and describes how Tūhoe came to occupy them and the duration of their occupation. Information about these claims came from tribal oral sources and original manuscripts, as well as from more generally accessible sources.
The development of colonial expansion patterns is discussed in Chapter Two. The contention is that they were based on materialistic considerations and legal pretexts to justify the acquisition of Māori lands. Hostilities between Māori and Government in the Bay of Plenty are dealt with in Chapter Three. Particular attention is paid to the causes of the hostilities and the complex racial and political misunderstandings which contributed to the inevitability of war. As a result of these encounters, the New Zealand Settlements Act was imposed.
Chapter Four covers the implementation of its provisions through the Compensation Court. The failings of this Court and its commissioners and field officials are exposed.
Chapter Five examines the settlement of Tūhoe lands in Ōpouriao and Waimana, as well as the changing fortunes of some of the settlers who took advantage of the settlement scheme. After placing the experiences of Tūhoe people within the wider context of what had taken place in New Zealand, Chapter Six focuses on Tūhoe attempts to bring the wrongs they had suffered to the attention of Government. In retrospect these early Tūhoe attempts at redress show that much has to be learnt about presenting substantial submissions. It was obvious that much of what was known by the elders then, though recorded, was never used in evidence to support their petitions. Nonetheless, without the existence of these manuscripts, present attempts would not be possible.
Chapter Seven gives a basis for a proposed just settlement for the confiscation of Tūhoe lands. In order to provide a guide for monetary compensation, details of values of Tūhoe confiscated land have been sought from official records. Compensation for the denial of justice, the loss of human life, land and property, remain open for negotiation.
Finally, while certain conclusions can be and are drawn from these investigations, the end of the story remains unwritten. It will depend on the outcome of new Tūhoe attempts to gain redress from the appropriate statutory body.

text: Te manemanerau a te kāwanatanga: A history of the confiscation of Tūhoe lands in the Bay of Plenty This thesis endeavours to show that Tūhoe lands should never have been confiscated and that Tūhoe efforts to gain compensation have been totally unsuccessful to date. When certain lands within the confiscated district of the Bay of Plenty were returned to the tribes there, Tūhoe were not granted any. Furthermore, lands which actually belonged to Tūhoe were granted to other tribes.
Although the major focus is on issues specific to Tūhoe, these are viewed within the wider context of nineteenth century land acquisition in New Zealand. This study looks at Tūhoe historical claims to disputed lands included in the confiscation district of the Bay of Plenty. Chapter One traces the extent of Tūhoe territories within the confiscation district and describes how Tūhoe came to occupy them and the duration of their occupation. Information about these claims came from tribal oral sources and original manuscripts, as well as from more generally accessible sources.
The development of colonial expansion patterns is discussed in Chapter Two. The contention is that they were based on materialistic considerations and legal pretexts to justify the acquisition of Māori lands. Hostilities between Māori and Government in the Bay of Plenty are dealt with in Chapter Three. Particular attention is paid to the causes of the hostilities and the complex racial and political misunderstandings which contributed to the inevitability of war. As a result of these encounters, the New Zealand Settlements Act was imposed.
Chapter Four covers the implementation of its provisions through the Compensation Court. The failings of this Court and its commissioners and field officials are exposed.
Chapter Five examines the settlement of Tūhoe lands in Ōpouriao and Waimana, as well as the changing fortunes of some of the settlers who took advantage of the settlement scheme. After placing the experiences of Tūhoe people within the wider context of what had taken place in New Zealand, Chapter Six focuses on Tūhoe attempts to bring the wrongs they had suffered to the attention of Government. In retrospect these early Tūhoe attempts at redress show that much has to be learnt about presenting substantial submissions. It was obvious that much of what was known by the elders then, though recorded, was never used in evidence to support their petitions. Nonetheless, without the existence of these manuscripts, present attempts would not be possible.
Chapter Seven gives a basis for a proposed just settlement for the confiscation of Tūhoe lands. In order to provide a guide for monetary compensation, details of values of Tūhoe confiscated land have been sought from official records. Compensation for the denial of justice, the loss of human life, land and property, remain open for negotiation.
Finally, while certain conclusions can be and are drawn from these investigations, the end of the story remains unwritten. It will depend on the outcome of new Tūhoe attempts to gain redress from the appropriate statutory body.

year: 1987