title: Comparing volcanic glass shards in unfertilized and fertilized Andisols derived from rhyolitic tephras, New Zealand: evidence for accelerated weathering and implications for land management

authors: Taylor, Matthew D.

abstract: Enhanced weathering associated with the use of phosphate fertilizers has already been identified in some of the major farming areas of New Zealand and there is need to evaluate its effects on soil properties and the implications for soil management. We assess changes in the character of volcanic glass shards in topsoils (010 cm depth) of two tephra-derived Andisols of differing ages (Udivitrands, Hapludands), and with and without long-term fertilization, to test if fertilizing accelerates the weathering of soil constituents. Using visual assessment based on scanning electron microscopy and electron microprobe analyses of glass shards from samples from paired sites, we show that the average sizes of the shards and the sharpness of the glass-shard edges (angularity) diminished with the age of the soil, and that these decreases were more marked in the soils that had been fertilized. Silica polymorphs were observed only in the older soil (Hapludand) that had been fertilized. We concluded that the addition of phosphate-containing fertilizer enhanced the dissolution of volcanic glass, consistent with phosphoric acid and F--induced dealumination and desilication, and thus soil weathering has been accelerated. The Al and Si may subsequently coprecipitate as secondary minerals, such as allophane. However, silica polymorphs may form where Al activity is low. The occurrence of neogenic silica in topsoils (despite high annual rainfall that should result in desilication of the topsoil and reprecipitation of silica deeper in the soil) is explained by the seasonality of fertilizer application and the spring-summer climate, where the soil remains moist for periods sufficiently long enough for the dissolution of volcanic glass (and possibly other aluminosilicates), the formation of Al-humus complexes, and the subsequent precipitation of silica in dry periods. Some implications of the accelerated weathering for soil management are discussed.

text: Comparing volcanic glass shards in unfertilized and fertilized Andisols derived from rhyolitic tephras, New Zealand: evidence for accelerated weathering and implications for land management Enhanced weathering associated with the use of phosphate fertilizers has already been identified in some of the major farming areas of New Zealand and there is need to evaluate its effects on soil properties and the implications for soil management. We assess changes in the character of volcanic glass shards in topsoils (010 cm depth) of two tephra-derived Andisols of differing ages (Udivitrands, Hapludands), and with and without long-term fertilization, to test if fertilizing accelerates the weathering of soil constituents. Using visual assessment based on scanning electron microscopy and electron microprobe analyses of glass shards from samples from paired sites, we show that the average sizes of the shards and the sharpness of the glass-shard edges (angularity) diminished with the age of the soil, and that these decreases were more marked in the soils that had been fertilized. Silica polymorphs were observed only in the older soil (Hapludand) that had been fertilized. We concluded that the addition of phosphate-containing fertilizer enhanced the dissolution of volcanic glass, consistent with phosphoric acid and F--induced dealumination and desilication, and thus soil weathering has been accelerated. The Al and Si may subsequently coprecipitate as secondary minerals, such as allophane. However, silica polymorphs may form where Al activity is low. The occurrence of neogenic silica in topsoils (despite high annual rainfall that should result in desilication of the topsoil and reprecipitation of silica deeper in the soil) is explained by the seasonality of fertilizer application and the spring-summer climate, where the soil remains moist for periods sufficiently long enough for the dissolution of volcanic glass (and possibly other aluminosilicates), the formation of Al-humus complexes, and the subsequent precipitation of silica in dry periods. Some implications of the accelerated weathering for soil management are discussed.

year: 2016

title: Ten years of MIREX: reflections, challenges and opportunities

authors: Downie, J. Stephen

abstract: The Music Information Retrieval Evaluation eXchange (MIREX) has been run annually since 2005, with the October 2014 plenary marking its tenth iteration. By 2013, MIREX has evaluated approximately 2000 individual music information retrieval (MIR) algorithms for a wide range of tasks over 37 different test collections. MIREX has involved researchers from over 29 different contrives with a median of 109 individual participants per year. This pater summarizes the history of MIREX form its earliest planning meeting in 2001 to the present. It reflects upon the administrative, financial, and technological challenges MIREX has faced and describes how those challenges have been surmounted. We propose new funding models, a distributed evaluation framework, and more holistic user experience evaluation tasks-some evolutionary, some revolutionary-for the continued success of MIREX. We hope that this paper will inspire MIR community members to contribute their ideas so MIREX can have many more successful years to come.

text: Ten years of MIREX: reflections, challenges and opportunities The Music Information Retrieval Evaluation eXchange (MIREX) has been run annually since 2005, with the October 2014 plenary marking its tenth iteration. By 2013, MIREX has evaluated approximately 2000 individual music information retrieval (MIR) algorithms for a wide range of tasks over 37 different test collections. MIREX has involved researchers from over 29 different contrives with a median of 109 individual participants per year. This pater summarizes the history of MIREX form its earliest planning meeting in 2001 to the present. It reflects upon the administrative, financial, and technological challenges MIREX has faced and describes how those challenges have been surmounted. We propose new funding models, a distributed evaluation framework, and more holistic user experience evaluation tasks-some evolutionary, some revolutionary-for the continued success of MIREX. We hope that this paper will inspire MIR community members to contribute their ideas so MIREX can have many more successful years to come.

year: 2014

title: Moko – A Research Project

authors: Te Awekotuku, Ngahuia

subjects: Maori

abstract: Moko colours the lives, and the skins, of all the people involved in the making of this book “Mau Moko”, which began as the Marsden project, “Ta Moko – Culture, Body Modification, and the Psychology of Identity”, 2001-2005. We proposed to study the origins, significance, technology and practice of Ta Moko from the pre-contact period to contemporary times, and to explore how this important art form has become a dynamic and positive assertion of being Maori in our changing world.

text: Moko – A Research Project Moko colours the lives, and the skins, of all the people involved in the making of this book “Mau Moko”, which began as the Marsden project, “Ta Moko – Culture, Body Modification, and the Psychology of Identity”, 2001-2005. We proposed to study the origins, significance, technology and practice of Ta Moko from the pre-contact period to contemporary times, and to explore how this important art form has become a dynamic and positive assertion of being Maori in our changing world.

year: 2008