title: Creating whanaungatanga: Kaupapa Maori support in the Psychology Department at the University of Waikato

authors: Masters-Awatere, Bridgette

subjects: Maori students

abstract: Attendance at university has been recognized by some as a competitive environment that does not cater for the co-operative philosophy followed by many Maori.  Within the Psychology Department at the University of Waikato there have been efforts since the Departments early days to place emphasis on the Maori cultural experience, but there were few Maori students and no Maori staff back then.  Now, in 2004, the Department has a team of Maori staff and courses with Maori content at both undergraduate and graduate levels.  Yet the environment that the students move in is still competitive. Grades are based on individual assessment through undergraduate level. At graduate level the emphasis on group dynamics comes to the fore.  The availability and accessibility of Maori staff at different levels in a Kaupapa Maori programme provides one of the strategies of support for maori students at Waikato.  This paper discusses the issues around managing, delivering and providing opportunities so that Maori students studying psychology feel supported for the duration of their time at Waikato University.

text: Creating whanaungatanga: Kaupapa Maori support in the Psychology Department at the University of Waikato Attendance at university has been recognized by some as a competitive environment that does not cater for the co-operative philosophy followed by many Maori.  Within the Psychology Department at the University of Waikato there have been efforts since the Departments early days to place emphasis on the Maori cultural experience, but there were few Maori students and no Maori staff back then.  Now, in 2004, the Department has a team of Maori staff and courses with Maori content at both undergraduate and graduate levels.  Yet the environment that the students move in is still competitive. Grades are based on individual assessment through undergraduate level. At graduate level the emphasis on group dynamics comes to the fore.  The availability and accessibility of Maori staff at different levels in a Kaupapa Maori programme provides one of the strategies of support for maori students at Waikato.  This paper discusses the issues around managing, delivering and providing opportunities so that Maori students studying psychology feel supported for the duration of their time at Waikato University.

year: 2004-12

title: Effects of lake trophic state and seasonal cycling on production and bioaccumulation of methylmercury in Te Arawa Lakes

authors: Chong, Grace-Lynn

abstract: There are natural sources of Mercury in New Zealand, primarily derived from volcanic activity and geothermal vents. Mercury (Hg) and its organic derivative, methylmercury (MeHg), are highly toxic to both the environment and human health. Of particular concern is the ability of MeHg to bioaccumulate in aquatic food webs, leading to increased toxicity in higher trophic organisms. Given that fish constitute a significant component of the local diet, comprehensive monitoring of Hg and MeHg concentrations is essential for developing effective mitigation strategies. Such efforts are critical to controlling Hg contamination in the environment and aquatic biota, as well as informing the public about lakes with elevated mercury levels. Previous Hg studies in New Zealand have been limited in scope, with monitoring efforts focused on only a few lakes rather than a comprehensive assessment across multiple ecosystems. Additionally, most existing research has primarily examined elemental Hg, with limited investigation into the distribution and bioavailability of MeHg.   

This study aims to comprehensively assess Hg and MeHg concentrations in 11 lakes of the Taupo Volcanic Zone. The study assessed Hg and MeHg concentrations in lake water and aquatic biota, including trout, crayfish (koura), and mussels (kakahi). To achieve this, Hg and MeHg in the water were measured using diffusive gradients in thin films (DGT) samplers, while tissue analyses determined Hg, MeHg and additional trace elements in the selected species. The findings of this study are expected to clarify the distribution and bioaccumulation of Hg and MeHg within lake ecosystems and to elucidate their transfer through the aquatic food web. These results will provide a scientific basis for assessing ecological and human health risks associated with mercury exposure, particularly for culturally and recreationally important species. The outcomes will inform lake management and monitoring strategies by identifying key pathways of mercury uptake and potential bioindicator species, and may guide the development of targeted mitigation measures, such as catchment management or advisories on species consumption. Collectively, this research will support evidence-based decision-making for freshwater ecosystem protection and long-term contaminant management.  

The results of this study revealed that total mercury (THg) and MeHg concentrations in trout, koura, and kakahi from Lakes Rotorua, Rotoiti, and Rotomahana exceeded WHO recommended safety thresholds. This study also found that a substantial proportion of THg was comprised of MeHg, which was predominantly accumulated in muscle tissue, whereas THg was primarily concentrated in the liver. The findings further indicated that eutrophication, lake stratification and hypolimnetic anoxia contribute to the enhanced production and bioaccumulation of Hg and MeHg within these aquatic systems. Additionally, selenium (Se) demonstrated a potential protective effect against MeHg toxicity in aquatic organisms.

text: Effects of lake trophic state and seasonal cycling on production and bioaccumulation of methylmercury in Te Arawa Lakes There are natural sources of Mercury in New Zealand, primarily derived from volcanic activity and geothermal vents. Mercury (Hg) and its organic derivative, methylmercury (MeHg), are highly toxic to both the environment and human health. Of particular concern is the ability of MeHg to bioaccumulate in aquatic food webs, leading to increased toxicity in higher trophic organisms. Given that fish constitute a significant component of the local diet, comprehensive monitoring of Hg and MeHg concentrations is essential for developing effective mitigation strategies. Such efforts are critical to controlling Hg contamination in the environment and aquatic biota, as well as informing the public about lakes with elevated mercury levels. Previous Hg studies in New Zealand have been limited in scope, with monitoring efforts focused on only a few lakes rather than a comprehensive assessment across multiple ecosystems. Additionally, most existing research has primarily examined elemental Hg, with limited investigation into the distribution and bioavailability of MeHg.   

This study aims to comprehensively assess Hg and MeHg concentrations in 11 lakes of the Taupo Volcanic Zone. The study assessed Hg and MeHg concentrations in lake water and aquatic biota, including trout, crayfish (koura), and mussels (kakahi). To achieve this, Hg and MeHg in the water were measured using diffusive gradients in thin films (DGT) samplers, while tissue analyses determined Hg, MeHg and additional trace elements in the selected species. The findings of this study are expected to clarify the distribution and bioaccumulation of Hg and MeHg within lake ecosystems and to elucidate their transfer through the aquatic food web. These results will provide a scientific basis for assessing ecological and human health risks associated with mercury exposure, particularly for culturally and recreationally important species. The outcomes will inform lake management and monitoring strategies by identifying key pathways of mercury uptake and potential bioindicator species, and may guide the development of targeted mitigation measures, such as catchment management or advisories on species consumption. Collectively, this research will support evidence-based decision-making for freshwater ecosystem protection and long-term contaminant management.  

The results of this study revealed that total mercury (THg) and MeHg concentrations in trout, koura, and kakahi from Lakes Rotorua, Rotoiti, and Rotomahana exceeded WHO recommended safety thresholds. This study also found that a substantial proportion of THg was comprised of MeHg, which was predominantly accumulated in muscle tissue, whereas THg was primarily concentrated in the liver. The findings further indicated that eutrophication, lake stratification and hypolimnetic anoxia contribute to the enhanced production and bioaccumulation of Hg and MeHg within these aquatic systems. Additionally, selenium (Se) demonstrated a potential protective effect against MeHg toxicity in aquatic organisms.

year: 2025

title: Finite dissipation in anisotropic magnetohydrodynamic turbulence

authors: Bandyopadhyay, R.

subjects: Science & Technology

abstract: In the presence of an externally supported, mean magnetic field, a turbulent, conducting medium, such as plasma, becomes anisotropic. This mean magnetic field, which is separate from the fluctuating, turbulent part of the magnetic field, has considerable effects on the dynamics of the system. In this paper, we examine the dissipation rates for decaying incompressible magnetohydrodynamic (MHD) turbulence with an increasing Reynolds number and in the presence of a mean magnetic field of varying strength. Proceeding numerically, we find that, as the Reynolds number increases, the dissipation rate asymptotes to a finite value for each magnetic-field strength, confirming the Kármán-Howarth hypothesis as applied to MHD. The asymptotic value of the dimensionless dissipation rate is initially suppressed from the zero-mean-field value by the mean magnetic field but then approaches a constant value for higher values of the mean-field strength. Additionally, for comparison, we perform a set of two-dimensional (2DMHD) and a set of reduced MHD (RMHD) simulations. We find that the RMHD results lie very close to the values corresponding to the high-mean-field limit of the three-dimensional runs while the 2DMHD results admit distinct values far from both the zero-mean-field cases and the high-mean-field limit of the threedimensional cases. These findings provide firm underpinnings for numerous applications in space and astrophysics wherein von Kármán decay of turbulence is assumed.

text: Finite dissipation in anisotropic magnetohydrodynamic turbulence In the presence of an externally supported, mean magnetic field, a turbulent, conducting medium, such as plasma, becomes anisotropic. This mean magnetic field, which is separate from the fluctuating, turbulent part of the magnetic field, has considerable effects on the dynamics of the system. In this paper, we examine the dissipation rates for decaying incompressible magnetohydrodynamic (MHD) turbulence with an increasing Reynolds number and in the presence of a mean magnetic field of varying strength. Proceeding numerically, we find that, as the Reynolds number increases, the dissipation rate asymptotes to a finite value for each magnetic-field strength, confirming the Kármán-Howarth hypothesis as applied to MHD. The asymptotic value of the dimensionless dissipation rate is initially suppressed from the zero-mean-field value by the mean magnetic field but then approaches a constant value for higher values of the mean-field strength. Additionally, for comparison, we perform a set of two-dimensional (2DMHD) and a set of reduced MHD (RMHD) simulations. We find that the RMHD results lie very close to the values corresponding to the high-mean-field limit of the three-dimensional runs while the 2DMHD results admit distinct values far from both the zero-mean-field cases and the high-mean-field limit of the threedimensional cases. These findings provide firm underpinnings for numerous applications in space and astrophysics wherein von Kármán decay of turbulence is assumed.

year: 2018