title: Marine demosponge responses to a changing ocean; effects of sedimentation and temperature increases on Tethya burtoni metabolism

authors: Beets, Fenna Linde

subjects: Sponge

abstract: As atmospheric CO₂ levels currently increase at an unprecedented rate, the effects of climate change are increasingly recognized as a significant threat. Changes to climate are predicted to influence natural systems, including increased storm events, that for an erosion prone country like New Zealand means exacerbated sedimentation in coastal habitats. Additionally, climate change is increasing sea surface temperatures globally and will continue to do so in coming decades. More studies investigating the effects of climate related pressures on marine sponge physiology are needed. These unique invertebrates are a diverse, ubiquitous and functionally important group. Studies examining climate change effects on sponges tend to investigate tropical species and in this regard, limited work has been done in New Zealand.
This research investigates how the pressures of increasing sea surface temperature and sedimentation affects the metabolism of the temperate demosponge, Tethya burtoni. Aquaria based experiments were conducted while ancillary in situ data investigated current day temperature and sedimentation in various T. burtoni habitats. Experiments addressed the immediate respiration response of T. burtoni under four sediment concentration treatments (ambient loads; 20 and 100 mg l⁻¹, storm proxy loads; 500 and 1000 mg l⁻¹) and four sediment grain size classes (<500-250 µm, <250-125 µm, <125-63 µm, <63 µm) at 500 mg l⁻¹. An additional experiment investigated the effects of long-term exposure (20-days) to fine sediments (<63 µm) at a storm proxy load (500 mg l⁻¹). Finally, the effects of IPCC projected sea surface temperature increase of low change; 2°C and high change; 4°C were investigated. Temperature treatments were based on the Tauranga mean annual sea surface temperature; 18°C and summer maximum; 23°, while IPCC projections were added to the latter giving treatments of 25°C and 27°C. 
High sediment loads at storm proxy concentrations significantly reduced the respiration rate of T. burtoni, while ambient concentrations had no significant effect. The two finest sediment grain size classes also reduced respiration rates significantly. These results suggest a protective response to reduce further clogging of the aquiferous system. The long-term experiment did not indicate any differences in respiration in the treatment group. Supplementary observations indicate that this may have been due to an issue with aquaria conditions. Sedimentation results in situ found that T. burtoni habitats experience varying amounts of sedimentation, though grain size compositions show similarity across sites. The temperature experiment indicated that 25°C and 27°C had significant impacts on T. burtoni survival with significant disease prevalence and morphological changes. The 18°C and 23°C had no significant effect on survival despite some signs of physiological stress present in the latter. Temperature data collected in situ confirms experimental ranges used, though with greater variability. These results suggest that a temperature threshold between 23°C and 25°C may exist and that in the absence of adaptation or acclimation, T. burtoni may be compromised under future conditions. The loss of sponge populations and even increased reductions in metabolic processes, as they relate to important ecosystem services such as benthic carbon flux, could have a significant effect on coastal trophic dynamics.

text: Marine demosponge responses to a changing ocean; effects of sedimentation and temperature increases on Tethya burtoni metabolism As atmospheric CO₂ levels currently increase at an unprecedented rate, the effects of climate change are increasingly recognized as a significant threat. Changes to climate are predicted to influence natural systems, including increased storm events, that for an erosion prone country like New Zealand means exacerbated sedimentation in coastal habitats. Additionally, climate change is increasing sea surface temperatures globally and will continue to do so in coming decades. More studies investigating the effects of climate related pressures on marine sponge physiology are needed. These unique invertebrates are a diverse, ubiquitous and functionally important group. Studies examining climate change effects on sponges tend to investigate tropical species and in this regard, limited work has been done in New Zealand.
This research investigates how the pressures of increasing sea surface temperature and sedimentation affects the metabolism of the temperate demosponge, Tethya burtoni. Aquaria based experiments were conducted while ancillary in situ data investigated current day temperature and sedimentation in various T. burtoni habitats. Experiments addressed the immediate respiration response of T. burtoni under four sediment concentration treatments (ambient loads; 20 and 100 mg l⁻¹, storm proxy loads; 500 and 1000 mg l⁻¹) and four sediment grain size classes (<500-250 µm, <250-125 µm, <125-63 µm, <63 µm) at 500 mg l⁻¹. An additional experiment investigated the effects of long-term exposure (20-days) to fine sediments (<63 µm) at a storm proxy load (500 mg l⁻¹). Finally, the effects of IPCC projected sea surface temperature increase of low change; 2°C and high change; 4°C were investigated. Temperature treatments were based on the Tauranga mean annual sea surface temperature; 18°C and summer maximum; 23°, while IPCC projections were added to the latter giving treatments of 25°C and 27°C. 
High sediment loads at storm proxy concentrations significantly reduced the respiration rate of T. burtoni, while ambient concentrations had no significant effect. The two finest sediment grain size classes also reduced respiration rates significantly. These results suggest a protective response to reduce further clogging of the aquiferous system. The long-term experiment did not indicate any differences in respiration in the treatment group. Supplementary observations indicate that this may have been due to an issue with aquaria conditions. Sedimentation results in situ found that T. burtoni habitats experience varying amounts of sedimentation, though grain size compositions show similarity across sites. The temperature experiment indicated that 25°C and 27°C had significant impacts on T. burtoni survival with significant disease prevalence and morphological changes. The 18°C and 23°C had no significant effect on survival despite some signs of physiological stress present in the latter. Temperature data collected in situ confirms experimental ranges used, though with greater variability. These results suggest that a temperature threshold between 23°C and 25°C may exist and that in the absence of adaptation or acclimation, T. burtoni may be compromised under future conditions. The loss of sponge populations and even increased reductions in metabolic processes, as they relate to important ecosystem services such as benthic carbon flux, could have a significant effect on coastal trophic dynamics.

year: 2017

title: Stratigraphy and development of the Late Miocene-Early Pleistocene Hawke’s Bay forearc basin

authors: Bland, Kyle J.

subjects: Hawke’s Bay

abstract: A Late Miocene-Early Pleistocene mixed carbonate-siliciclastic sedimentary succession about 2 500 m thick in the Hawke’s Bay forearc basin is the focus of a basin analysis. The area under investigation covers 3 500 km2 of western and central Hawke’s Bay. The stratigraphy of Hawke’s Bay Basin is characterised by dramatic vertical and lateral facies changes and significant fluxes of siliciclastic sediment through the Late Miocene and Pliocene. This project aims to better understand the character and origin of the sedimentary succession in the basin. Geological mapping has been undertaken at a scale of 1:25000, with data managed in an ARCINFO geodatabase, following the database model employed in the IGNS QMap programme.
Along the western margin of the basin there is progressive southward onlap of late Cenozoic strata on to basement. The oldest units are of Late Miocene (Tongaporutuan) age and the youngest onlap units are of latest Pliocene (Nukumaruan) age. Geological mapping of the basin fill places constraints on the magnitude (about 10 km) and timing (Pleistocene) of most of the offset on the North Island Shear Belt.
Lithofacies have been described and interpreted representing fluvial, estuarine, shoreface and inner- to outer-shelf environments. Conglomerate facies are representative of sediment-saturated prograding fluvial braidplains and river deltas. These units are dominated by greywacke gravels and record the erosion of the Kaweka-Ahimanawa Ranges. Sandstone facies typically comprise very well sorted, clean non-cemented units of 10-50 m thickness that accumulated in innershelf environments. Siltstone facies probably accumulated in relatively quiet, middle- to outer-shelf water depths, and comprise well-sorted, firm non-cemented units with occasional tephra interbeds. Limestone facies represent examples of continent-attached cool-water carbonate systems that developed in response to strong tidal currents and a high nutrient flux during the Pliocene. These facies are examples of mixed siliciclastic-bioclastic sedimentary systems. Of these facies the widespread distribution and thickness of sandstone and limestone units present the most potential for hydrocarbon reservoirs. Similarly, the distribution of siltstone and mudstone beds provides adequate seal rocks. Mangapanian limestone facies have already been targeted as potential petroleum reservoirs (e.g. Kereru-1). Geological mapping suggests that potential hydrocarbon reservoir and seal rocks occur extensively in the subsurface.

text: Stratigraphy and development of the Late Miocene-Early Pleistocene Hawke’s Bay forearc basin A Late Miocene-Early Pleistocene mixed carbonate-siliciclastic sedimentary succession about 2 500 m thick in the Hawke’s Bay forearc basin is the focus of a basin analysis. The area under investigation covers 3 500 km2 of western and central Hawke’s Bay. The stratigraphy of Hawke’s Bay Basin is characterised by dramatic vertical and lateral facies changes and significant fluxes of siliciclastic sediment through the Late Miocene and Pliocene. This project aims to better understand the character and origin of the sedimentary succession in the basin. Geological mapping has been undertaken at a scale of 1:25000, with data managed in an ARCINFO geodatabase, following the database model employed in the IGNS QMap programme.
Along the western margin of the basin there is progressive southward onlap of late Cenozoic strata on to basement. The oldest units are of Late Miocene (Tongaporutuan) age and the youngest onlap units are of latest Pliocene (Nukumaruan) age. Geological mapping of the basin fill places constraints on the magnitude (about 10 km) and timing (Pleistocene) of most of the offset on the North Island Shear Belt.
Lithofacies have been described and interpreted representing fluvial, estuarine, shoreface and inner- to outer-shelf environments. Conglomerate facies are representative of sediment-saturated prograding fluvial braidplains and river deltas. These units are dominated by greywacke gravels and record the erosion of the Kaweka-Ahimanawa Ranges. Sandstone facies typically comprise very well sorted, clean non-cemented units of 10-50 m thickness that accumulated in innershelf environments. Siltstone facies probably accumulated in relatively quiet, middle- to outer-shelf water depths, and comprise well-sorted, firm non-cemented units with occasional tephra interbeds. Limestone facies represent examples of continent-attached cool-water carbonate systems that developed in response to strong tidal currents and a high nutrient flux during the Pliocene. These facies are examples of mixed siliciclastic-bioclastic sedimentary systems. Of these facies the widespread distribution and thickness of sandstone and limestone units present the most potential for hydrocarbon reservoirs. Similarly, the distribution of siltstone and mudstone beds provides adequate seal rocks. Mangapanian limestone facies have already been targeted as potential petroleum reservoirs (e.g. Kereru-1). Geological mapping suggests that potential hydrocarbon reservoir and seal rocks occur extensively in the subsurface.

year: 2004

title: Cultural knowledge and identity for wellbeing and success: Trying to make the connections in the north of New Zealand.

authors: Hohepa, Margie Kahukura

subjects: New Zealand

abstract: This paper argues that secure cultural identity is essential to wellbeing and cultural identity is important to Māori youth participation and success. The roles of community and schools in developing secure cultural identity are increasingly complex, as both become increasingly more culturally and ethnically diverse in many parts of the world.
The paper discusses findings from student survey data from a 2 year project ‘Te Wehi Nui a Mamao: Maximising the potential of tribal marae and regional language among youth', which began in July 2008, supported by funding from New Zealand's Foundation of Research, Science and Technology. This project aims to strengthen the relevance of tribal marae and regional Maori language among Maori youth, which are identified as important to Māori cultural identity.
Inter-generational transfer of tribal marae knowledge and language is becoming more compromised. Many cultural values are defined on marae. Tribal leaders have long been concerned about disconnections between Māori youth and tribal marae, poor knowledge of regional dialect and the potential negative consequences for full participation in society. .It appears that Māori youth are disconnected from regional language dialects and marae knowledge now more than ever. Reconnecting Māori youth with these two sources of tribal identity is the key to the purpose of this project.

text: Cultural knowledge and identity for wellbeing and success: Trying to make the connections in the north of New Zealand. This paper argues that secure cultural identity is essential to wellbeing and cultural identity is important to Māori youth participation and success. The roles of community and schools in developing secure cultural identity are increasingly complex, as both become increasingly more culturally and ethnically diverse in many parts of the world.
The paper discusses findings from student survey data from a 2 year project ‘Te Wehi Nui a Mamao: Maximising the potential of tribal marae and regional language among youth', which began in July 2008, supported by funding from New Zealand's Foundation of Research, Science and Technology. This project aims to strengthen the relevance of tribal marae and regional Maori language among Maori youth, which are identified as important to Māori cultural identity.
Inter-generational transfer of tribal marae knowledge and language is becoming more compromised. Many cultural values are defined on marae. Tribal leaders have long been concerned about disconnections between Māori youth and tribal marae, poor knowledge of regional dialect and the potential negative consequences for full participation in society. .It appears that Māori youth are disconnected from regional language dialects and marae knowledge now more than ever. Reconnecting Māori youth with these two sources of tribal identity is the key to the purpose of this project.

year: 2010