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: Domain-independent automatic keyphrase indexing with small training sets

authors: Medelyan, Olena

subjects: computer science

abstract: Keyphrases are widely used in both physical and digital libraries as a brief, but precise, summary of documents. They help organize material based on content, provide thematic access, represent search results, and assist with navigation. Manual assignment is expensive because trained human indexers must reach an understanding of the document and select appropriate descriptors according to defined cataloging rules. We propose a new method that enhances automatic keyphrase extraction by using semantic information about terms and phrases gleaned from a domain-specific thesaurus. The key advantage of the new approach is that it performs well with very little training data. We evaluate it on a large set of manually indexed documents in the domain of agriculture, compare its consistency with a group of six professional indexers, and explore its performance on smaller collections of documents in other domains and of French and Spanish documents.

text: Domain-independent automatic keyphrase indexing with small training sets Keyphrases are widely used in both physical and digital libraries as a brief, but precise, summary of documents. They help organize material based on content, provide thematic access, represent search results, and assist with navigation. Manual assignment is expensive because trained human indexers must reach an understanding of the document and select appropriate descriptors according to defined cataloging rules. We propose a new method that enhances automatic keyphrase extraction by using semantic information about terms and phrases gleaned from a domain-specific thesaurus. The key advantage of the new approach is that it performs well with very little training data. We evaluate it on a large set of manually indexed documents in the domain of agriculture, compare its consistency with a group of six professional indexers, and explore its performance on smaller collections of documents in other domains and of French and Spanish documents.

year: 2008-03

title: Whānau mentoring, Māori youth and crime

authors: Joseph, Robert

abstract: This article will discuss how the whänau was the traditional institution for teaching and nurturing children through (among other things) effective mentoring, and how children were taught tikanga, or the ‘right way’ to think, speak, act and become. Traditional leadership development, whänau dysfunction and whänau renewal are also discussed, followed by my conclusions. This article will not be discussing the place of colonisation, high unemployment, lower education rates and other socio-economic disparities among Mäori that play a part in the causes and perpetuation of Mäori youth and crime. A discussion on the Treaty of Waitangi, indigenous rights, and Mäori development is also omitted although the importance of each of these areas is acknowledged. As the theme of this issue of Childrenz Issues is ‘seeking pathways beyond colonisation’, the focus of this article is on Mäori dealing appropriately with the problems of Mäori youth and crime through effective mentoring within the institution of the whänau.

text: Whānau mentoring, Māori youth and crime This article will discuss how the whänau was the traditional institution for teaching and nurturing children through (among other things) effective mentoring, and how children were taught tikanga, or the ‘right way’ to think, speak, act and become. Traditional leadership development, whänau dysfunction and whänau renewal are also discussed, followed by my conclusions. This article will not be discussing the place of colonisation, high unemployment, lower education rates and other socio-economic disparities among Mäori that play a part in the causes and perpetuation of Mäori youth and crime. A discussion on the Treaty of Waitangi, indigenous rights, and Mäori development is also omitted although the importance of each of these areas is acknowledged. As the theme of this issue of Childrenz Issues is ‘seeking pathways beyond colonisation’, the focus of this article is on Mäori dealing appropriately with the problems of Mäori youth and crime through effective mentoring within the institution of the whänau.

year: 2007-01