title: Rapid carbon accumulation in a peatland following Late Holocene tephra deposition, New Zealand

authors: Ratcliffe, Joshua Lee

abstract: Contemporary measurements of carbon (C) accumulation rates in peatlands around the world often show the C sink to be stronger on average than at times in the past. Alteration of global nutrient cycles could be contributing to elevated carbon accumulation in the present day. Here we examine the effect of volcanic inputs of nutrients on peatland C accumulation in Moanatuatua Bog, New Zealand, by examining a high-resolution Late Holocene C accumulation record during which powerful volcanic eruptions occurred, depositing two visible rhyolitic tephra layers (Taupo, 232 ± 10 CE; Kaharoa, 1314 ± 12 CE). Carbon accumulation rates since c. 50 CE, well before any human presence, increased from a background rate of 23 g C m−2 yr−1 up to 110 g C m−2 yr−1 following the deposition of the Taupo Tephra, and 84 g C m−2 yr−1 following the deposition of the Kaharoa Tephra. Smaller but nevertheless marked increases in C accumulation additionally occurred in association with the deposition of three andesitic-dacitic cryptotephras (each ≤ ∼1 mm thick) of the Tufa Trig Formation between the Taupo and Kaharoa events. These five periods of elevated C uptake, especially those associated with the relatively thick Taupo and Kaharoa tephras, were accompanied by shifts in nutrient stoichiometry, indicating that there was greater availability of phosphorus (P) relative to nitrogen (N) and C during the period of high C uptake. Such P was almost certainly derived from volcanic sources, with P being present in the volcanic glass at Moanatuatua, and many of the eruptions described being associated with the local deposition of the P rich mineral apatite. We found peatland C accumulation to be tightly coupled to N and P accumulation, suggesting nutrient inputs exert a strong control on rates of peat accumulation. Nutrient stoichiometry indicated a strong ability to recover P within the ecosystem, with C:P ratios being higher than most other peatlands in the literature. We conclude that nutrient inputs, deriving from volcanic eruptions, have been very important for C accumulation rates in the past. Therefore, the elevated nutrient inputs occurring in the present day could offer a more plausible explanation, as opposed to a climatic component, for observed high contemporary C accumulation in New Zealand peatlands.

text: Rapid carbon accumulation in a peatland following Late Holocene tephra deposition, New Zealand Contemporary measurements of carbon (C) accumulation rates in peatlands around the world often show the C sink to be stronger on average than at times in the past. Alteration of global nutrient cycles could be contributing to elevated carbon accumulation in the present day. Here we examine the effect of volcanic inputs of nutrients on peatland C accumulation in Moanatuatua Bog, New Zealand, by examining a high-resolution Late Holocene C accumulation record during which powerful volcanic eruptions occurred, depositing two visible rhyolitic tephra layers (Taupo, 232 ± 10 CE; Kaharoa, 1314 ± 12 CE). Carbon accumulation rates since c. 50 CE, well before any human presence, increased from a background rate of 23 g C m−2 yr−1 up to 110 g C m−2 yr−1 following the deposition of the Taupo Tephra, and 84 g C m−2 yr−1 following the deposition of the Kaharoa Tephra. Smaller but nevertheless marked increases in C accumulation additionally occurred in association with the deposition of three andesitic-dacitic cryptotephras (each ≤ ∼1 mm thick) of the Tufa Trig Formation between the Taupo and Kaharoa events. These five periods of elevated C uptake, especially those associated with the relatively thick Taupo and Kaharoa tephras, were accompanied by shifts in nutrient stoichiometry, indicating that there was greater availability of phosphorus (P) relative to nitrogen (N) and C during the period of high C uptake. Such P was almost certainly derived from volcanic sources, with P being present in the volcanic glass at Moanatuatua, and many of the eruptions described being associated with the local deposition of the P rich mineral apatite. We found peatland C accumulation to be tightly coupled to N and P accumulation, suggesting nutrient inputs exert a strong control on rates of peat accumulation. Nutrient stoichiometry indicated a strong ability to recover P within the ecosystem, with C:P ratios being higher than most other peatlands in the literature. We conclude that nutrient inputs, deriving from volcanic eruptions, have been very important for C accumulation rates in the past. Therefore, the elevated nutrient inputs occurring in the present day could offer a more plausible explanation, as opposed to a climatic component, for observed high contemporary C accumulation in New Zealand peatlands.

year: 2020

title: Architects as nowcasters of housing construction

authors: Holmes, Mark J.

subjects: nowcasting

abstract: For more than four decades, the New Zealand Institute of Economic Research (NZIER) has conducted a two-question, quarterly survey of architect forecasts of public and private sector construction expenditure. This qualitative survey is published one week after the end of each quarter and nine weeks ahead of the official quantitative data thereby giving architect opinion nowcasting status. This paper covers selected aspects of this unexplored series with particular reference to residential housing construction and the value-added information from architects as nowcasters. Specifically, we consider several qualitative-to-quantitative conversion methods, in-sample and out-of-sample performance, cyclical features and respondent dynamics. Although our work relates to architects - a sub-sector of the service industry - our results have a wider application to business survey questions using ordered qualitative responses.

text: Architects as nowcasters of housing construction For more than four decades, the New Zealand Institute of Economic Research (NZIER) has conducted a two-question, quarterly survey of architect forecasts of public and private sector construction expenditure. This qualitative survey is published one week after the end of each quarter and nine weeks ahead of the official quantitative data thereby giving architect opinion nowcasting status. This paper covers selected aspects of this unexplored series with particular reference to residential housing construction and the value-added information from architects as nowcasters. Specifically, we consider several qualitative-to-quantitative conversion methods, in-sample and out-of-sample performance, cyclical features and respondent dynamics. Although our work relates to architects - a sub-sector of the service industry - our results have a wider application to business survey questions using ordered qualitative responses.

year: 2009

title: Beyond structuralism: Exploring a semantic based approach for describing the Māori language in grammar books and textbooks for pedagogical purposes

authors: Taiapa, Michael William

subjects: Māori

abstract: Since the 1950s, the advancements and developments in English language studies has had a profound impact on its description that has made it less syntactically driven and more communicatively oriented. This has the potential to influence language description moving it from a purely structurally focused orientation to a more semantically focused one that could influence pedagogic outcomes in more meaningful and useful ways. Nevertheless, in the case of the Māori language, its description has largely focused on structure linguistics that was prevalent in the 19th and early 20th centuries. There has been very little focus on a semantic description and this, in turn, is reflected in grammar books and textbooks on te reo. This thesis set out to explore a semantic approach to describe te reo and to rethink how this type of description may be realized and included in the design of grammar books and textbooks for the teaching and learning of te reo in the broader field of second language pedagogy and acquisition. The thesis also includes a practical component in which a small sample of Māori language teachers were interviewed to determine how linguistic and/ or semantic approaches to describe te reo may have or have impacted on their own beliefs, attitudes, and teaching practices (See, Chapter 7). Thus, it is argued here that research-based studies, advancements, and developments in language descriptions over the past five decades (See, for example, Council of Europe, 1949; Fillmore, 1967; Longacre, 1968; & Crombie, 1985b) should play central roles in the design of a semantic based description of the Māori language from which a linguistic based description can significantly benefit.

text: Beyond structuralism: Exploring a semantic based approach for describing the Māori language in grammar books and textbooks for pedagogical purposes Since the 1950s, the advancements and developments in English language studies has had a profound impact on its description that has made it less syntactically driven and more communicatively oriented. This has the potential to influence language description moving it from a purely structurally focused orientation to a more semantically focused one that could influence pedagogic outcomes in more meaningful and useful ways. Nevertheless, in the case of the Māori language, its description has largely focused on structure linguistics that was prevalent in the 19th and early 20th centuries. There has been very little focus on a semantic description and this, in turn, is reflected in grammar books and textbooks on te reo. This thesis set out to explore a semantic approach to describe te reo and to rethink how this type of description may be realized and included in the design of grammar books and textbooks for the teaching and learning of te reo in the broader field of second language pedagogy and acquisition. The thesis also includes a practical component in which a small sample of Māori language teachers were interviewed to determine how linguistic and/ or semantic approaches to describe te reo may have or have impacted on their own beliefs, attitudes, and teaching practices (See, Chapter 7). Thus, it is argued here that research-based studies, advancements, and developments in language descriptions over the past five decades (See, for example, Council of Europe, 1949; Fillmore, 1967; Longacre, 1968; & Crombie, 1985b) should play central roles in the design of a semantic based description of the Māori language from which a linguistic based description can significantly benefit.

year: 2023