title: Assessing drivers of plantation forest productivity on eroded and non-eroded soils in hilly land, eastern North Island, New Zealand

authors: Heaphy, Marie

abstract: Methods: The impact of soil erosion by mass movement on forest productivity was investigated in a paired plot trial in a planted forest in a mainly hilly to steepland catchment (Pakuratahi) near Napier, eastern North Island, New Zealand. Tree growth and form were measured and soil properties analysed to compare productivity and productivity drivers in adjacent non-eroded and eroded plots. Background: The effect of soil erosion on New Zealand production forestry is not well known and there has been no research prior to our study into the relationship between soil nutrient status and planted forests growing in eroded soils in steeplands. Results: Regression analysis showed that the decreased soil total nitrogen, total carbon, total phosphorus, and soil organic matter content in eroded plots had a negative impact on tree volume, resulting in a 10% decrease in measured tree volume. Based on an assessment of log quality, trees in the eroded plots were forecast to produce 16% less volume from high-quality pruned logs (with associated reduction in revenue of around $4000 per hectare), than trees in non-eroded plots. The total recoverable volume (TRV), estimated (for a 25-year rotation) from the measured Pinus radiata D. Don trees growing on the eroded sites, was valued at $68,500, about 9% less than the estimated TRV from trees measured on non-eroded plots ($76,000). Tree form and mean tree height in eroded and non-eroded plots were not significantly different. Conclusions: Soil erosion impacts production in planted forests. Afforestation of erodible land provides a valuable ecosystem service through land and soil stabilisation but this service is currently not reflected in the market prices for timber in New Zealand. Maintaining the productive capacity of erodible soils through practices such as fertilisation or continuous-cover forestry can add further costs to production forestry. To ensure that sustainable forest practices are carried out to protect the productivity of soils, financial incentives may be justified.

text: Assessing drivers of plantation forest productivity on eroded and non-eroded soils in hilly land, eastern North Island, New Zealand Methods: The impact of soil erosion by mass movement on forest productivity was investigated in a paired plot trial in a planted forest in a mainly hilly to steepland catchment (Pakuratahi) near Napier, eastern North Island, New Zealand. Tree growth and form were measured and soil properties analysed to compare productivity and productivity drivers in adjacent non-eroded and eroded plots. Background: The effect of soil erosion on New Zealand production forestry is not well known and there has been no research prior to our study into the relationship between soil nutrient status and planted forests growing in eroded soils in steeplands. Results: Regression analysis showed that the decreased soil total nitrogen, total carbon, total phosphorus, and soil organic matter content in eroded plots had a negative impact on tree volume, resulting in a 10% decrease in measured tree volume. Based on an assessment of log quality, trees in the eroded plots were forecast to produce 16% less volume from high-quality pruned logs (with associated reduction in revenue of around $4000 per hectare), than trees in non-eroded plots. The total recoverable volume (TRV), estimated (for a 25-year rotation) from the measured Pinus radiata D. Don trees growing on the eroded sites, was valued at $68,500, about 9% less than the estimated TRV from trees measured on non-eroded plots ($76,000). Tree form and mean tree height in eroded and non-eroded plots were not significantly different. Conclusions: Soil erosion impacts production in planted forests. Afforestation of erodible land provides a valuable ecosystem service through land and soil stabilisation but this service is currently not reflected in the market prices for timber in New Zealand. Maintaining the productive capacity of erodible soils through practices such as fertilisation or continuous-cover forestry can add further costs to production forestry. To ensure that sustainable forest practices are carried out to protect the productivity of soils, financial incentives may be justified.

year: 2014-07-02

title: Synthesis, Microstructure, and Mechanical Properties of a Novel Ti₂AlC/TiC/Al₂O₃In Situ Composite

authors: Zhang, Deliang

subjects: engineering

abstract: This paper describes a novel process for synthesizing a Ti₂AlC/TiC/Al₂O₃in situ composite. This route utilizes TiO₂, carbon, and Al powders as raw materials, and involves high-energy mechanical milling and powder sintering. The Ti₂AlC/TiC/Al₂O₃ bulk in situ composite produced has a phase composition of Ti₂AlC–20 vol% TiC–35 vol% Al₂O₃ with fine Al₂O₃ particles (size: 0.5–15 μm) embedded in a Ti₂AlC/TiC matrix. The Ti₂AlC grains exhibit a nanometer scale lamellar structure, and most of the Al₂O₃ grains contain fine cubic TiOmC1−m precipitates (size: 10–200 nm). The average hardness and bending strength of the composite are in the ranges of 11–12.5 GPa and 380–440 MPa, respectively. Here we have demonstrated that the mechanical performance (mainly hardness and bending strength) of the composite is directly correlated with the size of the Al2O3 particles present in the as-fabricated in situ composite.

text: Synthesis, Microstructure, and Mechanical Properties of a Novel Ti₂AlC/TiC/Al₂O₃In Situ Composite This paper describes a novel process for synthesizing a Ti₂AlC/TiC/Al₂O₃in situ composite. This route utilizes TiO₂, carbon, and Al powders as raw materials, and involves high-energy mechanical milling and powder sintering. The Ti₂AlC/TiC/Al₂O₃ bulk in situ composite produced has a phase composition of Ti₂AlC–20 vol% TiC–35 vol% Al₂O₃ with fine Al₂O₃ particles (size: 0.5–15 μm) embedded in a Ti₂AlC/TiC matrix. The Ti₂AlC grains exhibit a nanometer scale lamellar structure, and most of the Al₂O₃ grains contain fine cubic TiOmC1−m precipitates (size: 10–200 nm). The average hardness and bending strength of the composite are in the ranges of 11–12.5 GPa and 380–440 MPa, respectively. Here we have demonstrated that the mechanical performance (mainly hardness and bending strength) of the composite is directly correlated with the size of the Al2O3 particles present in the as-fabricated in situ composite.

year: 2006

title: Institutional Racism and the Dynamics of Privilege in Public Health

authors: Came, Heather

subjects: Institutional racism

abstract: Institutional racism, a pattern of differential access to material resources and power determined by race, advantages one sector of the population while disadvantaging another. Such racism is not only about conspicuous acts of violence but can be carried in the hold of mono-cultural perspectives. Overt state violation of principles contributes to the backdrop against which much less overt yet insidious violations occur. New Zealand health policy is one such mono-cultural domain. It is dominated by western bio-medical discourses that preclude and under-value Māori,  the indigenous peoples of this land, in the conceptualisation, structure, content, and processes of health policies, despite Te Tiriti o Waitangi  guarantees to protect Māori interests.

Since the 1980s, the Department of Health has committed to honouring the Treaty of Waitangi as the founding document of Māori-settler relationships and governance arrangements. Subsequent Waitangi Tribunal reports, produced by an independent Commission of Inquiry have documented the often-illegal actions of successive governments advancing the interests of Pākehā  at the expense of Māori. Institutional controls have not prevented inequities between Māori and non-Māori across a plethora of social and economic indicators.

Activist scholars work to expose and transform perceived inequities. My research interest lies in how Crown Ministers and officials within the public health sector practice institutional racism and privilege and how it can be transformed. Through dialogue with Māori working within the health sector, fuelled by critical analysis and strategic advice from a research whānau (family) of Māori health leaders and a Pākehā Tiriti worker, and embracing the traditions of feminist and critical race theory  I provide evidence of racism that can invoke strong emotional reactions. More disturbing is its normalisation to nigh imperceptibility within ones personal and professional life. The exposure of racism as a socially created phenomenon is a strength of the research presented here. 

My action orientation is my ethical response. Honouring Te Tiriti o Waitangi is a pathway to transforming racism. Such change is likely to be resisted by the Pākehā majority. This anticipated resistance is not a credible reason to weaken responsibility for such necessary change. Transforming institutional racism needs to be driven by senior managers, professional bodies, unions, and by communities. Policies, practices and leadership that enable institutional racism need to be systematically eliminated from the health sector. Crown officials must be supported to strengthen their professional accountabilities and to embrace ethical bicultural practice. Greater transparency could enable more effective monitoring of Crown behaviour and support transformed practice.

text: Institutional Racism and the Dynamics of Privilege in Public Health Institutional racism, a pattern of differential access to material resources and power determined by race, advantages one sector of the population while disadvantaging another. Such racism is not only about conspicuous acts of violence but can be carried in the hold of mono-cultural perspectives. Overt state violation of principles contributes to the backdrop against which much less overt yet insidious violations occur. New Zealand health policy is one such mono-cultural domain. It is dominated by western bio-medical discourses that preclude and under-value Māori,  the indigenous peoples of this land, in the conceptualisation, structure, content, and processes of health policies, despite Te Tiriti o Waitangi  guarantees to protect Māori interests.

Since the 1980s, the Department of Health has committed to honouring the Treaty of Waitangi as the founding document of Māori-settler relationships and governance arrangements. Subsequent Waitangi Tribunal reports, produced by an independent Commission of Inquiry have documented the often-illegal actions of successive governments advancing the interests of Pākehā  at the expense of Māori. Institutional controls have not prevented inequities between Māori and non-Māori across a plethora of social and economic indicators.

Activist scholars work to expose and transform perceived inequities. My research interest lies in how Crown Ministers and officials within the public health sector practice institutional racism and privilege and how it can be transformed. Through dialogue with Māori working within the health sector, fuelled by critical analysis and strategic advice from a research whānau (family) of Māori health leaders and a Pākehā Tiriti worker, and embracing the traditions of feminist and critical race theory  I provide evidence of racism that can invoke strong emotional reactions. More disturbing is its normalisation to nigh imperceptibility within ones personal and professional life. The exposure of racism as a socially created phenomenon is a strength of the research presented here. 

My action orientation is my ethical response. Honouring Te Tiriti o Waitangi is a pathway to transforming racism. Such change is likely to be resisted by the Pākehā majority. This anticipated resistance is not a credible reason to weaken responsibility for such necessary change. Transforming institutional racism needs to be driven by senior managers, professional bodies, unions, and by communities. Policies, practices and leadership that enable institutional racism need to be systematically eliminated from the health sector. Crown officials must be supported to strengthen their professional accountabilities and to embrace ethical bicultural practice. Greater transparency could enable more effective monitoring of Crown behaviour and support transformed practice.

year: 2012