title: Anthropogenic Influences on the Sedimentary Evolution of the Coromandel Harbour

authors: Harpur, Alexander

subjects: Coromandel Harbour

abstract: The Coromandel Harbour is located on the eastern side of the Coromandel Peninsula, North Island, New Zealand. To date, sedimentological research conducted in the harbour has been confined to nearshore areas, with limited data existing for the subtidal regions of the harbour. The primary aim of this thesis is to identify whether and how various human activities in the catchment have altered harbour-wide, intertidal and subtidal, sedimentation rates and sediment geochemistry. A secondary aim is to identify the sedimentary evolution of the whole Coromandel Harbour over broad time scales (i.e. thousands of years).

Sedimentological data has been collected from 17 intertidal and subtidal sediment cores. Cores have been analysed for down-core changes in sediment texture, mineralogy, observational characteristics and geochemistry measured through portable X-ray fluorescence (pXRF). A facies model constructed from this data has been used to interpret the sedimentary development of the harbour. Pre-human and anthropogenic sediment accumulation rates (SARs) have been estimated using radiocarbon dating, qualitative pollen analysis and facies analysis. Anthropogenic heavy metals have been interpreted against pre-human baselines to identify influences on natural contaminant levels, with specific values compared with regional contaminant guidelines to assess ecological threats. 

Deeply weathered soils developed in a subaerial environment somewhere between the last interglacial at c.120 ka and the extended last glacial maximum (eLGM) at 29 ka. These soils were overtopped by streambank and floodplain deposits at the eLGM to the onset of the mid-Holocene sea level rise at c.7500 cal yr B.P. As sea level rose, inundated eLGM and early estuarine sediments were initially pyritised in a stratified, restricted marine setting. Over time, sea level rose and the stratification of the harbour was destroyed, ceasing pyritisation. Streams began to rapidly aggrade at the harbour with the positive change in base level, giving early estuarine (c.7500-5000 cal yr B.P) subtidal SARs of ~0.31-0.45 mm/yr. As streams reached stable profiles, SARs decreased to generally conformable rates of 0.25-0.47 mm/yr in the intertidal regions and ~0.1-0.25 mm/yr in the subtidal regions during the pre-Polynesian phase (c.7500-700 cal yr B.P). Polynesian SARs (700-130 cal yr B.P) decreased to ~0.05-0.13 mm/yr. Whole European (1820 A.D-present) SARs in the northern parts of the harbour are ~0.52-0.77 mm/yr and appear to be chiefly related to mining and deforestation. Recent European (1975 A.D-present) SARs are ~3.52-10.37 mm/yr in the southern parts of the harbour and are chiefly related to pine plantation erosion. A secondary depocentre for pine plantation sediments appears to be at the inlet where rates of ~4.98 mm/yr occur. 

Only arsenic and mercury exist over Australian and New Zealand Environment and Conservation Council (ANZECC) Interim Sediment Quality Guidelines (ISQG) Low concentrations in anthropogenic sediments analysed. Maximum harbour-wide arsenic concentrations of up to 33.5 mg/kg that exceed the ISQG-Low value of 20 mg/kg are associated with mining related sediments near the Whangarahi Stream mouth. Maximum arsenic concentrations in pine plantation sediments is 22.3 mg/kg. Mercury may also exceed ISQG-Low/High values throughout all harbour sediments, though it is unclear whether mercury has been incorrectly measured by pXRF.

text: Anthropogenic Influences on the Sedimentary Evolution of the Coromandel Harbour The Coromandel Harbour is located on the eastern side of the Coromandel Peninsula, North Island, New Zealand. To date, sedimentological research conducted in the harbour has been confined to nearshore areas, with limited data existing for the subtidal regions of the harbour. The primary aim of this thesis is to identify whether and how various human activities in the catchment have altered harbour-wide, intertidal and subtidal, sedimentation rates and sediment geochemistry. A secondary aim is to identify the sedimentary evolution of the whole Coromandel Harbour over broad time scales (i.e. thousands of years).

Sedimentological data has been collected from 17 intertidal and subtidal sediment cores. Cores have been analysed for down-core changes in sediment texture, mineralogy, observational characteristics and geochemistry measured through portable X-ray fluorescence (pXRF). A facies model constructed from this data has been used to interpret the sedimentary development of the harbour. Pre-human and anthropogenic sediment accumulation rates (SARs) have been estimated using radiocarbon dating, qualitative pollen analysis and facies analysis. Anthropogenic heavy metals have been interpreted against pre-human baselines to identify influences on natural contaminant levels, with specific values compared with regional contaminant guidelines to assess ecological threats. 

Deeply weathered soils developed in a subaerial environment somewhere between the last interglacial at c.120 ka and the extended last glacial maximum (eLGM) at 29 ka. These soils were overtopped by streambank and floodplain deposits at the eLGM to the onset of the mid-Holocene sea level rise at c.7500 cal yr B.P. As sea level rose, inundated eLGM and early estuarine sediments were initially pyritised in a stratified, restricted marine setting. Over time, sea level rose and the stratification of the harbour was destroyed, ceasing pyritisation. Streams began to rapidly aggrade at the harbour with the positive change in base level, giving early estuarine (c.7500-5000 cal yr B.P) subtidal SARs of ~0.31-0.45 mm/yr. As streams reached stable profiles, SARs decreased to generally conformable rates of 0.25-0.47 mm/yr in the intertidal regions and ~0.1-0.25 mm/yr in the subtidal regions during the pre-Polynesian phase (c.7500-700 cal yr B.P). Polynesian SARs (700-130 cal yr B.P) decreased to ~0.05-0.13 mm/yr. Whole European (1820 A.D-present) SARs in the northern parts of the harbour are ~0.52-0.77 mm/yr and appear to be chiefly related to mining and deforestation. Recent European (1975 A.D-present) SARs are ~3.52-10.37 mm/yr in the southern parts of the harbour and are chiefly related to pine plantation erosion. A secondary depocentre for pine plantation sediments appears to be at the inlet where rates of ~4.98 mm/yr occur. 

Only arsenic and mercury exist over Australian and New Zealand Environment and Conservation Council (ANZECC) Interim Sediment Quality Guidelines (ISQG) Low concentrations in anthropogenic sediments analysed. Maximum harbour-wide arsenic concentrations of up to 33.5 mg/kg that exceed the ISQG-Low value of 20 mg/kg are associated with mining related sediments near the Whangarahi Stream mouth. Maximum arsenic concentrations in pine plantation sediments is 22.3 mg/kg. Mercury may also exceed ISQG-Low/High values throughout all harbour sediments, though it is unclear whether mercury has been incorrectly measured by pXRF.

year: 2016

title: The evolutionary history of the extinct ratite moa and New Zealand Neogene paleogeography

authors: Bunce, M.

subjects: ancient DNA

abstract: The ratite moa (Aves: Dinornithiformes) were a speciose group of massive graviportal avian herbivores that dominated the New Zealand (NZ) ecosystem until their extinction ≈600 years ago. The phylogeny and evolutionary history of this morphologically diverse order has remained controversial since their initial description in 1839. We synthesize mitochondrial phylogenetic information from 263 subfossil moa specimens from across NZ with morphological, ecological, and new geological data to create the first comprehensive phylogeny, taxonomy, and evolutionary timeframe for all of the species of an extinct order. We also present an important new geological/paleogeographical model of late Cenozoic NZ, which suggests that terrestrial biota on the North and South Island landmasses were isolated for most of the past 20–30 Ma. The data reveal that the patterns of genetic diversity within and between different moa clades reflect a complex history following a major marine transgression in the Oligocene, affected by marine barriers, tectonic activity, and glacial cycles. Surprisingly, the remarkable morphological radiation of moa appears to have occurred much more recently than previous early Miocene (ca. 15 Ma) estimates, and was coincident with the accelerated uplift of the Southern Alps just ca. 5–8.5 Ma. Together with recent fossil evidence, these data suggest that the recent evolutionary history of nearly all of the iconic NZ terrestrial biota occurred principally on just the South Island.

text: The evolutionary history of the extinct ratite moa and New Zealand Neogene paleogeography The ratite moa (Aves: Dinornithiformes) were a speciose group of massive graviportal avian herbivores that dominated the New Zealand (NZ) ecosystem until their extinction ≈600 years ago. The phylogeny and evolutionary history of this morphologically diverse order has remained controversial since their initial description in 1839. We synthesize mitochondrial phylogenetic information from 263 subfossil moa specimens from across NZ with morphological, ecological, and new geological data to create the first comprehensive phylogeny, taxonomy, and evolutionary timeframe for all of the species of an extinct order. We also present an important new geological/paleogeographical model of late Cenozoic NZ, which suggests that terrestrial biota on the North and South Island landmasses were isolated for most of the past 20–30 Ma. The data reveal that the patterns of genetic diversity within and between different moa clades reflect a complex history following a major marine transgression in the Oligocene, affected by marine barriers, tectonic activity, and glacial cycles. Surprisingly, the remarkable morphological radiation of moa appears to have occurred much more recently than previous early Miocene (ca. 15 Ma) estimates, and was coincident with the accelerated uplift of the Southern Alps just ca. 5–8.5 Ma. Together with recent fossil evidence, these data suggest that the recent evolutionary history of nearly all of the iconic NZ terrestrial biota occurred principally on just the South Island.

year: 2009

title: Co-opting or valuing the indigenous voice through translation? A decision for research teams

authors: Kidd, Jacquie

subjects: Māori

abstract: Although te reo Māori is an official language of Aotearoa New Zealand, translation of research material such as information sheets, consent forms and questionnaires into te reo Māori remains highly variable. Translation tends to occur in research projects where Māori lead the work and that exclusively focus on Māori communities and topics. Translations are not offered or undertaken as a matter of course for all research. As a team of Māori and Indigenous researchers working within the health sector, we believe that there are important questions that need to be explored around the practice of using Indigenous languages, rich in similes and metaphors, to convey English/Western concepts/constructs/ideologies. In this paper, we draw on the story of one project to deconstruct and challenge the hegemonic terms through which translation of research material occurs. We explore the messages that translated material sends to potential research participants.
We contend that the choice about whether to translate research material into te reo Māori is one that should be undertaken within a robust decision-making framework that considers the reasons for a translation and its impact on the participants. Translation should not be undertaken primarily to attract Māori participants, but should reliably signal that the research is being undertaken in a way that honours a Māori worldview.

text: Co-opting or valuing the indigenous voice through translation? A decision for research teams Although te reo Māori is an official language of Aotearoa New Zealand, translation of research material such as information sheets, consent forms and questionnaires into te reo Māori remains highly variable. Translation tends to occur in research projects where Māori lead the work and that exclusively focus on Māori communities and topics. Translations are not offered or undertaken as a matter of course for all research. As a team of Māori and Indigenous researchers working within the health sector, we believe that there are important questions that need to be explored around the practice of using Indigenous languages, rich in similes and metaphors, to convey English/Western concepts/constructs/ideologies. In this paper, we draw on the story of one project to deconstruct and challenge the hegemonic terms through which translation of research material occurs. We explore the messages that translated material sends to potential research participants.
We contend that the choice about whether to translate research material into te reo Māori is one that should be undertaken within a robust decision-making framework that considers the reasons for a translation and its impact on the participants. Translation should not be undertaken primarily to attract Māori participants, but should reliably signal that the research is being undertaken in a way that honours a Māori worldview.

year: 2019