title: The link between erosion, phosphorus and water quality

authors: Gibbs, Max M.

abstract: In lakes, the solubility of phosphorus (P) in water, and therefore its availability to aquatic plants (macrophytes and algae) for growth, is controlled by oxygen and pH. The supply of dissolved reactive P (DRP) to the lake water column is mostly from sediment release from
decomposing plant material and iron oxides during periods of low oxygen, although in Lake Rotorua and most of the other lakes on the central volcanic plateau, spring-fed streams carry relatively high concentrations of DRP into the lakes. The mechanism for releasing iron-bound DRP from the sediment focusses around the oxidation state iron (Fe) and manganese (Mn). In well oxygenated conditions iron exists in the oxidised state as ferric ions which form ferric oxides that are insoluble in water. These oxides sequester DRP as they precipitate and remove it from the water column. When the oxygen concentration falls to zero (anoxic conditions) iron exists in the reduced state as ferrous ions, which are soluble in water. As the ferric form reduces to the ferrous form it dissolves and the DRP bound to the iron is released into the water column where it is used by algae for growth. The algae eventually senesce and die, returning the P to the sediment as particulate P, where it can be recycled during the next period of anoxia.
Apart from recycling of algal biomass, P also comes from the catchment, bound to the iron oxides in soil particles. The P content of the soil is greatest in the finest soil particles, which are the first to be eroded by rainfall and do not settle until they reach the calm waters of a lake. There they augment the P load from the senescing algal biomass, thereby increasing the amount of DRP that can be released during the next anoxic event. Because of the high background concentration of dissolved inorganic nitrogen in the lake water, the addition of any DRP will stimulate algal growth and thus result in a deterioration of lake water quality. Land management strategies to reduce soil erosion include changes to the way land is farmed and the interception and retention of fine sediment using detention bunds.

text: The link between erosion, phosphorus and water quality In lakes, the solubility of phosphorus (P) in water, and therefore its availability to aquatic plants (macrophytes and algae) for growth, is controlled by oxygen and pH. The supply of dissolved reactive P (DRP) to the lake water column is mostly from sediment release from
decomposing plant material and iron oxides during periods of low oxygen, although in Lake Rotorua and most of the other lakes on the central volcanic plateau, spring-fed streams carry relatively high concentrations of DRP into the lakes. The mechanism for releasing iron-bound DRP from the sediment focusses around the oxidation state iron (Fe) and manganese (Mn). In well oxygenated conditions iron exists in the oxidised state as ferric ions which form ferric oxides that are insoluble in water. These oxides sequester DRP as they precipitate and remove it from the water column. When the oxygen concentration falls to zero (anoxic conditions) iron exists in the reduced state as ferrous ions, which are soluble in water. As the ferric form reduces to the ferrous form it dissolves and the DRP bound to the iron is released into the water column where it is used by algae for growth. The algae eventually senesce and die, returning the P to the sediment as particulate P, where it can be recycled during the next period of anoxia.
Apart from recycling of algal biomass, P also comes from the catchment, bound to the iron oxides in soil particles. The P content of the soil is greatest in the finest soil particles, which are the first to be eroded by rainfall and do not settle until they reach the calm waters of a lake. There they augment the P load from the senescing algal biomass, thereby increasing the amount of DRP that can be released during the next anoxic event. Because of the high background concentration of dissolved inorganic nitrogen in the lake water, the addition of any DRP will stimulate algal growth and thus result in a deterioration of lake water quality. Land management strategies to reduce soil erosion include changes to the way land is farmed and the interception and retention of fine sediment using detention bunds.

year: 2015

title: Engaging in research with Pacific communities as a non-Pacific researcher: reflecting on lessons learnt

authors: Flavell, Margaret

abstract: A key challenge for the cross-cultural researcher is how to maintain authenticity in the stories of participants, paying careful attention to any inherent power imbalances. In this article, we share our respective experiences of conducting research with Pacific students and their families in Aotearoa New Zealand as non-Pacific researchers. We discuss tensions we encountered regarding power and positionality, highlighting the importance of engaging with Pacific perspectives and methodologies to help counter these tensions. In our respective studies, we aimed to promote the voices of our participants and conduct research which prioritised Pacific values. We further appreciated that we must not let our own research agenda override the needs of our participants. We explain why we believe these ideas to be so important and draw tentative conclusions on ways to engage in research with Pacific families based on what we have learnt. The data presented from our respective studies highlight our approaches and present some of the challenges, as well as our efforts to engage in reciprocal, respectful relationships with our participants and their families. We hope that, in sharing our reflections, we may offer some useful insight to other researchers embarking on a similar journey to us.

text: Engaging in research with Pacific communities as a non-Pacific researcher: reflecting on lessons learnt A key challenge for the cross-cultural researcher is how to maintain authenticity in the stories of participants, paying careful attention to any inherent power imbalances. In this article, we share our respective experiences of conducting research with Pacific students and their families in Aotearoa New Zealand as non-Pacific researchers. We discuss tensions we encountered regarding power and positionality, highlighting the importance of engaging with Pacific perspectives and methodologies to help counter these tensions. In our respective studies, we aimed to promote the voices of our participants and conduct research which prioritised Pacific values. We further appreciated that we must not let our own research agenda override the needs of our participants. We explain why we believe these ideas to be so important and draw tentative conclusions on ways to engage in research with Pacific families based on what we have learnt. The data presented from our respective studies highlight our approaches and present some of the challenges, as well as our efforts to engage in reciprocal, respectful relationships with our participants and their families. We hope that, in sharing our reflections, we may offer some useful insight to other researchers embarking on a similar journey to us.

year: 2022

title: Positioning historical trauma theory within Aotearoa New Zealand

authors: Pihama, Leonie

abstract: This article explores the relevance of historical trauma theory for Mäori research. In exploring the impact of historical trauma upon Mäori it has become clear that the terminology associated with historical trauma theory is considered controversial in Aotearoa New Zealand. As such, this article provides an overview of key defi nitions relevant to historical trauma and explores these in relation to recent reporting related to the use of the terms “holocaust” and “genocide” in the context of colonization in Aotearoa New Zealand. It is argued that in order to engage fully with the impacts of colonization on Mäori wellbeing we must articulate fully the impact of historical trauma events and the contribution of those events to the negative health disparities experienced by many of our whänau (extended family), hapü (sub- tribes) and iwi (tribes).

text: Positioning historical trauma theory within Aotearoa New Zealand This article explores the relevance of historical trauma theory for Mäori research. In exploring the impact of historical trauma upon Mäori it has become clear that the terminology associated with historical trauma theory is considered controversial in Aotearoa New Zealand. As such, this article provides an overview of key defi nitions relevant to historical trauma and explores these in relation to recent reporting related to the use of the terms “holocaust” and “genocide” in the context of colonization in Aotearoa New Zealand. It is argued that in order to engage fully with the impacts of colonization on Mäori wellbeing we must articulate fully the impact of historical trauma events and the contribution of those events to the negative health disparities experienced by many of our whänau (extended family), hapü (sub- tribes) and iwi (tribes).

year: 2014