title: Quaternary environmental change in New Zealand: a review

authors: Newnham, Rewi M.

subjects: climate change

abstract: The discovery that orbital variations are the driving force behind Quaternary climate change provides an impetus to set local and regional records of environmental change into the global context, a principle that has been strongly embraced by Quaternary scientists working in New Zealand. Their major achievements and significant current initiatives are reviewed here. The importance of the New Zealand Quaternary stems from its geographical context: a climatically sensitive, remote oceanic, southern location spanning 17 degrees of the mid-latitudes; an obliquely convergent plate boundary setting resulting in a high mountain range athwart the prevailing westerlies, active volcanism, a youthful and dynamic landscape, and mountains high enough to maintain glaciers today; and a remarkably short prehistory. The resultant records show marked environmental changes due not only to climatic oscillations but also to vigorous, active tectonism and volcanism. The Taupo Volcanic Zone, containing the world's strongest concentration of youthful rhyolitic volcanoes, has produced at least 10 000 km3 of magma in the last 2 Ma. Climatic interpretations of records from marine sediments in the New Zealand region, together with several long sequences of alternating marine and terrestrial sediments, indicate broad synchrony with Northern Hemisphere events (within limitations of dating), although there are differences in detail for shorter-term climatic events. It is not yet certain that glacial advances coincided precisely with those in the Northern Hemisphere or were of similar duration. Late Cainozoic glaciation commenced c. 2.6-2.4 Ma but the record of glacial deposits is fragmentary and poorly dated except for the most recent events. The Last (Otira) Glaciation, from c. 100-10 ka, was characterized by at least five glacial advances including during the Last Glacial Maximum from 25 to 15 ka, when snowlines fell by 600-800 m. New Zealand evidence for cooling during the Younger Dryas stade is equivocal whilst isotopic records from speleothems, and other data, indicate warmer and wetter conditions from 10-7 ka, broadly conforming with records from mid-latitude Northern Hemisphere locations. Future advances will require sampling at shorter timescales, improvements in the accuracy and precision of existing dating methods and the development of new ones, extension of palaeoecological techniques to cover the full potential of New Zealand's diverse biota, and a stronger emphasis on quantification of palaeoclimatic parameters.

text: Quaternary environmental change in New Zealand: a review The discovery that orbital variations are the driving force behind Quaternary climate change provides an impetus to set local and regional records of environmental change into the global context, a principle that has been strongly embraced by Quaternary scientists working in New Zealand. Their major achievements and significant current initiatives are reviewed here. The importance of the New Zealand Quaternary stems from its geographical context: a climatically sensitive, remote oceanic, southern location spanning 17 degrees of the mid-latitudes; an obliquely convergent plate boundary setting resulting in a high mountain range athwart the prevailing westerlies, active volcanism, a youthful and dynamic landscape, and mountains high enough to maintain glaciers today; and a remarkably short prehistory. The resultant records show marked environmental changes due not only to climatic oscillations but also to vigorous, active tectonism and volcanism. The Taupo Volcanic Zone, containing the world's strongest concentration of youthful rhyolitic volcanoes, has produced at least 10 000 km3 of magma in the last 2 Ma. Climatic interpretations of records from marine sediments in the New Zealand region, together with several long sequences of alternating marine and terrestrial sediments, indicate broad synchrony with Northern Hemisphere events (within limitations of dating), although there are differences in detail for shorter-term climatic events. It is not yet certain that glacial advances coincided precisely with those in the Northern Hemisphere or were of similar duration. Late Cainozoic glaciation commenced c. 2.6-2.4 Ma but the record of glacial deposits is fragmentary and poorly dated except for the most recent events. The Last (Otira) Glaciation, from c. 100-10 ka, was characterized by at least five glacial advances including during the Last Glacial Maximum from 25 to 15 ka, when snowlines fell by 600-800 m. New Zealand evidence for cooling during the Younger Dryas stade is equivocal whilst isotopic records from speleothems, and other data, indicate warmer and wetter conditions from 10-7 ka, broadly conforming with records from mid-latitude Northern Hemisphere locations. Future advances will require sampling at shorter timescales, improvements in the accuracy and precision of existing dating methods and the development of new ones, extension of palaeoecological techniques to cover the full potential of New Zealand's diverse biota, and a stronger emphasis on quantification of palaeoclimatic parameters.

year: 1999

title: Sources and effects of catchment-derived bioavailable contaminants in Hamilton urban streams

authors: Valler, Tammy L.

subjects: Urban streams

abstract: Awareness of the consistently degraded state of urban streams, with lower biodiversity has heightened worldwide, increasing restoration initiatives to ameliorate the adverse effects. The present study examined anthropogenically-derived contaminants in water and sediments and bioaccumulation in tissues and bile of shortfin eels (Anguilla australis) in Hamilton City urban gully streams. Bioassays were also conducted with two native Crustacea; the amphipod Paracorophium lucasi and freshwater crayfish (kōura) (Paranephrops planifrons) to test endpoints of survival, reburial behaviour and growth. Results of dissolved Cu, Pb and Zn showed the industrial Waitawhiriwhiri catchment, with higher impervious surfaces, to have the greatest potential for generating contaminants in stream waters. Relationships between sediment contaminant concentrations and upstream % impervious area suggest an association with stormwater runoff and metal accumulation. Shortfin eels from Gibbons Creek and Lake Rotoroa bioaccumulated high concentrations of Pb and As respectively in livers, and PAH metabolite pyrene-1-glucuronide in bile was found in many eels, highlighting the bioavailability of these contaminants. Muscle tissues cocnentrations of Pb and Hg in some sites triggered food safety guidelines presenting a low risk for human consumption. Amphipods exposed to sediments from Lake Rotoroa had significantly reduced survival compared with those exposed to other site sediments in a 10-day sediment toxicity test. Photo-induced toxicity is not of concern for biota exposed to these sediments. Sediments did not induce any sub-lethal effect on reburial behaviour. Growth rates of kōura fed Salix fragilis leaf material incubated in Hamilton streams were not significantly different, and the short duration of the study meant conclusions could not be made on the significance of observed accumulated metals and metalloids on differences in growth rates. Results of this study highlight a number of locations in the Hamilton stream network, where contaminants are of concern, especially in streams with fully urbanised catchments with high effective imperviousness and legacies of past land use or pollution. Bioavailability of some metals, metalloids and PAHs is constraining the diversity of some species present in these streams, although not apparent for shortfin eels, as they are very common.

text: Sources and effects of catchment-derived bioavailable contaminants in Hamilton urban streams Awareness of the consistently degraded state of urban streams, with lower biodiversity has heightened worldwide, increasing restoration initiatives to ameliorate the adverse effects. The present study examined anthropogenically-derived contaminants in water and sediments and bioaccumulation in tissues and bile of shortfin eels (Anguilla australis) in Hamilton City urban gully streams. Bioassays were also conducted with two native Crustacea; the amphipod Paracorophium lucasi and freshwater crayfish (kōura) (Paranephrops planifrons) to test endpoints of survival, reburial behaviour and growth. Results of dissolved Cu, Pb and Zn showed the industrial Waitawhiriwhiri catchment, with higher impervious surfaces, to have the greatest potential for generating contaminants in stream waters. Relationships between sediment contaminant concentrations and upstream % impervious area suggest an association with stormwater runoff and metal accumulation. Shortfin eels from Gibbons Creek and Lake Rotoroa bioaccumulated high concentrations of Pb and As respectively in livers, and PAH metabolite pyrene-1-glucuronide in bile was found in many eels, highlighting the bioavailability of these contaminants. Muscle tissues cocnentrations of Pb and Hg in some sites triggered food safety guidelines presenting a low risk for human consumption. Amphipods exposed to sediments from Lake Rotoroa had significantly reduced survival compared with those exposed to other site sediments in a 10-day sediment toxicity test. Photo-induced toxicity is not of concern for biota exposed to these sediments. Sediments did not induce any sub-lethal effect on reburial behaviour. Growth rates of kōura fed Salix fragilis leaf material incubated in Hamilton streams were not significantly different, and the short duration of the study meant conclusions could not be made on the significance of observed accumulated metals and metalloids on differences in growth rates. Results of this study highlight a number of locations in the Hamilton stream network, where contaminants are of concern, especially in streams with fully urbanised catchments with high effective imperviousness and legacies of past land use or pollution. Bioavailability of some metals, metalloids and PAHs is constraining the diversity of some species present in these streams, although not apparent for shortfin eels, as they are very common.

year: 2013

title: Activating whanau (extended family) processes within a community and school literacy partnership

authors: Glynn, Ted

subjects: Maori Education

abstract: "The paper describes the positive outcomes of a home and school literacy partnership in one mainstream primary school where the principal and the large majority of students, teachers, and whānau belong to one Māori hapū (sub-tribe), Ngāti Whakaue. Participating students were identified by teachers as experiencing difficulties with reading and writing. They were assigned randomly to one of two conditions: (1) participating in their school’s regular reading programme (school group) or (2) participating also in the home tutored reading and writing programme (home and school group).

Students in the home and school group improved their reading and writing outcomes over and above the outcomes achieved by students participating only in the regular school programme. There were two key reasons for the success of this partnership. The first was parents and whānau members successful implementation of both a Māori language reading tutoring programme, Tatari, Tautoko Tauawhi, and the two components of the writing programme, Tuhi Atu Tui Mai and Whakaputa Whakaaro. The second was the professional educational and cultural expertise of the home and school liaison worker, Hiro. Because of her language and cultural expertise and her mana (acknowledged authority and standing), Hiro was able to engage Māori parents and whānau actively in the home and school project. The co-constructed narrative between Hiro and Mere (the second author) provided a salient context for understanding the power of culturally preferred pedagogy in establishing effective home and school partnerships."

text: Activating whanau (extended family) processes within a community and school literacy partnership "The paper describes the positive outcomes of a home and school literacy partnership in one mainstream primary school where the principal and the large majority of students, teachers, and whānau belong to one Māori hapū (sub-tribe), Ngāti Whakaue. Participating students were identified by teachers as experiencing difficulties with reading and writing. They were assigned randomly to one of two conditions: (1) participating in their school’s regular reading programme (school group) or (2) participating also in the home tutored reading and writing programme (home and school group).

Students in the home and school group improved their reading and writing outcomes over and above the outcomes achieved by students participating only in the regular school programme. There were two key reasons for the success of this partnership. The first was parents and whānau members successful implementation of both a Māori language reading tutoring programme, Tatari, Tautoko Tauawhi, and the two components of the writing programme, Tuhi Atu Tui Mai and Whakaputa Whakaaro. The second was the professional educational and cultural expertise of the home and school liaison worker, Hiro. Because of her language and cultural expertise and her mana (acknowledged authority and standing), Hiro was able to engage Māori parents and whānau actively in the home and school project. The co-constructed narrative between Hiro and Mere (the second author) provided a salient context for understanding the power of culturally preferred pedagogy in establishing effective home and school partnerships."

year: 2004