title: Leaching and uptake of nitrogen, and pasture production, associated with irrigation of treated wastewater, Taupō, New Zealand

authors: Telfer, Erin Isobel Charlotte

subjects: Wastewater

abstract: Secondary-treated wastewater from Taupō Township is irrigated onto perennial ryegrass (Lolium perenne) which is harvested and removed from the View Road wastewater treatment site. To determine the fate of the applied wastewater nitrogen, 48 undisturbed barrel lysimeters (30 cm diameter x 43 cm depth) were installed throughout 29 hectares. Centre pivot travelling irrigators were programmed to vary in speed to provide target wastewater application rates of about 0, 450, 550 and 650 kg N ha⁻¹yr⁻¹.
The targeted application treatments were not achieved, with the achieved nitrogen loading rates grouped into a low treatment (286 - 380 kg N ha⁻¹yr⁻¹), a medium treatment (380 - 445 kg N ha⁻¹yr⁻¹), and a high treatment (445 - 567 kg N ha⁻¹yr⁻¹). Nitrogen input in control sectors was assumed to be 5 kg N/ha/yr from atmospheric nitrogen deposition.
A mean of 4 to 6% of the applied nitrogen was leached. The mean amount of nitrogen leached from the high treatment (28.6 ± 10.1 kg N ha⁻¹yr⁻¹) was higher (P < 0.05) than from the low treatment (12.7 ± 4.2 kg N ha⁻¹yr⁻¹). The medium treatment (16.0 ± 7.2 kg N ha⁻¹yr⁻¹) was not significantly different than the low treatment or the high treatment. The mean amount of nitrogen leached from the control treatment was 2.8 ± 0.6 kg N ha⁻¹yr⁻¹. Nitrogen leaching that occurred in the high application treatment was below the consented limit of 30 kg N ha⁻¹yr⁻¹.
A mean of 79 to 100% of the applied nitrogen was removed by pasture. There were no significant differences in pasture dry matter production, or nitrogen removal, between the low treatment (13 922 ± 1196 kg DM ha⁻¹yr⁻¹and 341 ± 25 kg N ha⁻¹yr⁻¹), the medium treatment (13 543 ± 1475 kg DM ha⁻¹yr⁻¹ and 360 ± 51 kg N ha⁻¹yr⁻¹), and the high treatment (15 285 ± 1919 kg DM ha⁻¹yr⁻¹ and 385 ± 43 kg N ha⁻¹yr⁻¹). Pasture production was higher (P < 0.001) in irrigated pastures (mean of all irrigated treatments, 14 250 ± 349 kg DM ha⁻¹yr⁻¹) than unirrigated controls (5300 ± 839 kg DM ha⁻¹yr⁻¹).
A mean of -4 to 16% of the applied wastewater nitrogen was unaccounted for. The majority of unrecovered nitrogen was presumed to be volatilised with lower potential for denitrification and soil storage.
A second experiment was undertaken to determine whether a five week or a ten week harvesting frequency would result in greater pasture production and nitrogen removal. During the ten month trial, 265 kg N ha⁻¹ of wastewater nitrogen was irrigated and pasture plots (1 m x 1 m) were cut with a mower. Nitrogen removal and pasture production were higher (P < 0.05) with a five week harvesting interval (8231 ± 186 kg DM ha⁻¹ and 250 ± 5 kg N ha⁻¹) than a ten week harvesting interval (7354 ± 67 kg DM ha⁻¹ and 191 ± 3 kg N ha⁻¹). Harvesting at five week intervals during late-November to May (late-spring to late-autumn) and ten week intervals from May until early-November (late-autumn to mid-spring) is recommended to maximise both pasture production and nitrogen removal, while minimising harvesting costs.

text: Leaching and uptake of nitrogen, and pasture production, associated with irrigation of treated wastewater, Taupō, New Zealand Secondary-treated wastewater from Taupō Township is irrigated onto perennial ryegrass (Lolium perenne) which is harvested and removed from the View Road wastewater treatment site. To determine the fate of the applied wastewater nitrogen, 48 undisturbed barrel lysimeters (30 cm diameter x 43 cm depth) were installed throughout 29 hectares. Centre pivot travelling irrigators were programmed to vary in speed to provide target wastewater application rates of about 0, 450, 550 and 650 kg N ha⁻¹yr⁻¹.
The targeted application treatments were not achieved, with the achieved nitrogen loading rates grouped into a low treatment (286 - 380 kg N ha⁻¹yr⁻¹), a medium treatment (380 - 445 kg N ha⁻¹yr⁻¹), and a high treatment (445 - 567 kg N ha⁻¹yr⁻¹). Nitrogen input in control sectors was assumed to be 5 kg N/ha/yr from atmospheric nitrogen deposition.
A mean of 4 to 6% of the applied nitrogen was leached. The mean amount of nitrogen leached from the high treatment (28.6 ± 10.1 kg N ha⁻¹yr⁻¹) was higher (P < 0.05) than from the low treatment (12.7 ± 4.2 kg N ha⁻¹yr⁻¹). The medium treatment (16.0 ± 7.2 kg N ha⁻¹yr⁻¹) was not significantly different than the low treatment or the high treatment. The mean amount of nitrogen leached from the control treatment was 2.8 ± 0.6 kg N ha⁻¹yr⁻¹. Nitrogen leaching that occurred in the high application treatment was below the consented limit of 30 kg N ha⁻¹yr⁻¹.
A mean of 79 to 100% of the applied nitrogen was removed by pasture. There were no significant differences in pasture dry matter production, or nitrogen removal, between the low treatment (13 922 ± 1196 kg DM ha⁻¹yr⁻¹and 341 ± 25 kg N ha⁻¹yr⁻¹), the medium treatment (13 543 ± 1475 kg DM ha⁻¹yr⁻¹ and 360 ± 51 kg N ha⁻¹yr⁻¹), and the high treatment (15 285 ± 1919 kg DM ha⁻¹yr⁻¹ and 385 ± 43 kg N ha⁻¹yr⁻¹). Pasture production was higher (P < 0.001) in irrigated pastures (mean of all irrigated treatments, 14 250 ± 349 kg DM ha⁻¹yr⁻¹) than unirrigated controls (5300 ± 839 kg DM ha⁻¹yr⁻¹).
A mean of -4 to 16% of the applied wastewater nitrogen was unaccounted for. The majority of unrecovered nitrogen was presumed to be volatilised with lower potential for denitrification and soil storage.
A second experiment was undertaken to determine whether a five week or a ten week harvesting frequency would result in greater pasture production and nitrogen removal. During the ten month trial, 265 kg N ha⁻¹ of wastewater nitrogen was irrigated and pasture plots (1 m x 1 m) were cut with a mower. Nitrogen removal and pasture production were higher (P < 0.05) with a five week harvesting interval (8231 ± 186 kg DM ha⁻¹ and 250 ± 5 kg N ha⁻¹) than a ten week harvesting interval (7354 ± 67 kg DM ha⁻¹ and 191 ± 3 kg N ha⁻¹). Harvesting at five week intervals during late-November to May (late-spring to late-autumn) and ten week intervals from May until early-November (late-autumn to mid-spring) is recommended to maximise both pasture production and nitrogen removal, while minimising harvesting costs.

year: 2013

title: Stratigraphy and development of c. 17 000 year old Lake Maratoto, North Island, New Zealand, with some inferences about postglacial climatic change

authors: Green, John D.

subjects: paleolimnology

abstract: The stratigraphy and geomorphology of Lake Maratoto and its surrounds were investigated as part of a programme of paleolimnological studies based on sediment cores from lakes in northern North Island. Changes in the lake and catchment were inferred from variations in sediment character, the correlation and timing being determined from distinctive tephra layers in the sediments and by radiocarbon dating. Nineteen new C-l4 dates, on gyttja or peat, are reported (old T½, years B.P,): 11 on tephras (Mamaku Ash 6830 ±90. Wk227; Rotoma Ash 8370 ± 90, Wk522; 8350 ± 100, Wk523; Opepe Tephra 9370 ± 210, Wk230; Mangamate Tephra 9700 ± 140, Wk23l; 10000 ± 120, Wk232; Waiohau Ash 12 200 ± 230, Wk233; 12500 ± 190, Wk234; 12450 ± 200, Wk5l5; 12300 ± 190,Wk516; RotoruaAsh 13450 ± 120, Wk511); 5 on the deposition of Hinuera Formation alluvium (16 300 ± 250, Wk239; 16 900 ± 470, Wk240; 17050 ± 200, Wk358; 16200 +360 -340, Wk509; 15 850 ± 130, Wk510); and 3 on basal peat of the Rukuhia bog (10 250 ± 90, Wk114; 15200 ± 130, Wk534; 10600 ± 90, Wk553).
Lake Maratoto originated c. 17 000 years ago when a small valley was dammed by volcanogenic alluvium (Hinuera Formation). From c. 17 000 to c. 14 000 years ago the lake was about 2 m deep with clear water. Marginal peat first developed at c. 15000 years ago, reducing the area of the lake by about one-half by c. 13 000 years ago. Lake area then expanded, possibly because of marginal erosion and/or oxidation of the peat, to its maximum size at the present day. The adjacent Rukuhia peat bog grew rapidly from c. 11 000 years ago and is now 8 m thick immediately to the west of the lake. As a result of this growth, the lake became dystrophic and deepened (3.5 m at c. 7000 years ago, 6.4 m at c. 2000 years ago, and 7. 1 m today).
The developmental history suggests that net precipitation increased at c. 15 000 years ago, increased further at c. 11 000 years ago, remaining high to c. 7000 years ago at least, but with a decline at or before c. 2000 years ago. There may have been a distinctly wetter or windier period from c. 10 000 to 9000 years ago.
This interpretation is consistent with other reconstructions of postglacial climate in the Southern Hemisphere.

text: Stratigraphy and development of c. 17 000 year old Lake Maratoto, North Island, New Zealand, with some inferences about postglacial climatic change The stratigraphy and geomorphology of Lake Maratoto and its surrounds were investigated as part of a programme of paleolimnological studies based on sediment cores from lakes in northern North Island. Changes in the lake and catchment were inferred from variations in sediment character, the correlation and timing being determined from distinctive tephra layers in the sediments and by radiocarbon dating. Nineteen new C-l4 dates, on gyttja or peat, are reported (old T½, years B.P,): 11 on tephras (Mamaku Ash 6830 ±90. Wk227; Rotoma Ash 8370 ± 90, Wk522; 8350 ± 100, Wk523; Opepe Tephra 9370 ± 210, Wk230; Mangamate Tephra 9700 ± 140, Wk23l; 10000 ± 120, Wk232; Waiohau Ash 12 200 ± 230, Wk233; 12500 ± 190, Wk234; 12450 ± 200, Wk5l5; 12300 ± 190,Wk516; RotoruaAsh 13450 ± 120, Wk511); 5 on the deposition of Hinuera Formation alluvium (16 300 ± 250, Wk239; 16 900 ± 470, Wk240; 17050 ± 200, Wk358; 16200 +360 -340, Wk509; 15 850 ± 130, Wk510); and 3 on basal peat of the Rukuhia bog (10 250 ± 90, Wk114; 15200 ± 130, Wk534; 10600 ± 90, Wk553).
Lake Maratoto originated c. 17 000 years ago when a small valley was dammed by volcanogenic alluvium (Hinuera Formation). From c. 17 000 to c. 14 000 years ago the lake was about 2 m deep with clear water. Marginal peat first developed at c. 15000 years ago, reducing the area of the lake by about one-half by c. 13 000 years ago. Lake area then expanded, possibly because of marginal erosion and/or oxidation of the peat, to its maximum size at the present day. The adjacent Rukuhia peat bog grew rapidly from c. 11 000 years ago and is now 8 m thick immediately to the west of the lake. As a result of this growth, the lake became dystrophic and deepened (3.5 m at c. 7000 years ago, 6.4 m at c. 2000 years ago, and 7. 1 m today).
The developmental history suggests that net precipitation increased at c. 15 000 years ago, increased further at c. 11 000 years ago, remaining high to c. 7000 years ago at least, but with a decline at or before c. 2000 years ago. There may have been a distinctly wetter or windier period from c. 10 000 to 9000 years ago.
This interpretation is consistent with other reconstructions of postglacial climate in the Southern Hemisphere.

year: 1985

title: Taonga tuku iho: Intergenerational transfer of raranga and whatu

authors: Te Kanawa, Kahutoi Mere

subjects: Intergenerational Knowledge Transfer through Raranga and Whatu

abstract: The intergenerational transfer of Māori weaving knowledge is based on the succession and continuum of raranga and whatu skills. This study will show how the genesis of inherent know-ledge and skills imbues the nature and continuity of our own cultural practice, especially specific to raranga, whatu and wider areas such as tukutuku. Kaupapa Māori research methodology u-sing the framework of Te Aho tapu provides the methodological approach for this research.  In particular I draw upon the experiences of our whānau and the pedagogical processes used by five generations to define the fundamental underpinnings of a Kaupapa Māori approach to knowledge transfer within, and between, generations of whānau and hapū. Another important driving force behind this work is a need to express the actual practice of intergenerational trans-mission as evidence of the centrality of ako or Māori pedagogy in terms of raranga.
The research questions I pose, are based around the difference between, mōhiotanga, mātauranga, māramatanga and mahi within in a raranga and whatu context.
What is the importance of indigenous intergenerational knowledge transmission through raranga/whatu?
Is it possible to understand the skills and intricacies of an artefact that gives us knew, yet old knowledge from the expertise left by our kairaranga?
The creative component of this research includes as a feature the reproduction of a kete pūkoro, also known as a pututu, especially in the northern tribal dialects (Williams, 2005). The pūkoro is held in the the Otago Museum and the kairaranga has not been identified. The Ngai Tahu dialect emphasise this kete is a pūkoro (Dr J.Williams, personal communication, 2015) which is the term I utilise throughout this research as an acknowledgement to the kairaranga from the southern region of Otakau. A kete pūkoro is a finely woven kete which was used to squeeze the juice from the tutu berries (Beever, 1991). The pūkoro is the only known such taonga that exists and is so fragile that it‘s no longer exhibited. The fragility of the piece is prone to damage through touch, movement and light exposure, so is kept in a temperature controlled draw in the Otago Museum, Dunedin. The uniqueness of this piece of work is the construction, form and the function. The pūkoro sits at the centre of the practice for this research as an example of intergenerational knowledge transfer of the taonga. The raranga technique will be analyzed and the function and form will be replicated to understand more about the kairaranga through the making of the pūkoro. The artefact will be researched and analyzed considering every detail possible, documenting, and reflecting on the processes. Whilst the pūkoro is the centre piece that shows the refinement of knowledge of the kairaranga, it demonstrated the skills and ability to produce a taonga that could be used as a practical kete for sieving out the poisonous kernels of the tutu, only allowing the juice to be strained through it.
Why the pūkoro?
When I first came upon the pūkoro, it was only by osmosis. The pūkoro was stored away in a dark area, and I was attracted to the space where it was stored while viewing kete whakairo that were put out for display for me. I was the kaiako at Otago University for the Toi Onamata classes within Te Tumu, the Māori and Pacific studies Faculty. I arranged with the museum curator to view the kete whakairo in their collection.
I felt drawn to that part of the museum after feeling a strong sense of needing to see what was kept in the dark. I had a strong feeling and attraction to viewing what was kept in the dark, so I asked the curator if I could see what was kept in that space. I was told it was a very fragile kete made of harakeke which they considered was an un-usual shape and it was noted that it was a very old piece. and that the shape of it was unusual, and it was a very old. This made me more curious, as there was something particularly that I was alluring about me to this taonga.
When closely analysing the piece, I realised I could not see the commencement or completion. With closer inspection of the construction, it became more obvious to me, as a kairaranga that the skills and technical detail of horizontal and vertical twills of overlaying patterns used, were woven that way for a purpose.
From that first viewing, I was able to tell the curator, exactly what this artefact was used for, what material it was made out of and that the technical construction of the kete pūkoro was different from others I had viewed before.
It was this moment in time, that I had an epiphany, that this piece of work could tell a story of the unknown kairaranga. I decided right from that point, that I would try my best to bring to light the technical ability of the raranga weave and why it was constructed in such a way.
Like anything, further research needed to be done on the pūkoro, to understand the purpose of this fine piece of work. This was the impetus of my study. The questions I asked myself were:
Why was I attracted to this dark space? For me it was my wairuatanga, alluring me to a space with a deep sense that there was a reason I needed to be there at that time. It was that strong spiritual belief that enabled me to listen to that and to go into the space the pūkoro was being held.
How did I know and understand the construction of the kete pūkoro?. This was about my Mōhiotanga, using my own tacit knowledge, years of observation and passion to engage with a taonga left from a kairaranga of the past century.
What was the purpose of reconstructing this taonga? – This is about the mātauranga imbued in the construction of the Kete Pūkoro. It was to engage in further research to find out more detail beyond what I already knew.
How can I best share this knowledge and practice? – This is about Māramatanga, as I have been always taught, there is no point knowing a skill, and information if it is not shared.

text: Taonga tuku iho: Intergenerational transfer of raranga and whatu The intergenerational transfer of Māori weaving knowledge is based on the succession and continuum of raranga and whatu skills. This study will show how the genesis of inherent know-ledge and skills imbues the nature and continuity of our own cultural practice, especially specific to raranga, whatu and wider areas such as tukutuku. Kaupapa Māori research methodology u-sing the framework of Te Aho tapu provides the methodological approach for this research.  In particular I draw upon the experiences of our whānau and the pedagogical processes used by five generations to define the fundamental underpinnings of a Kaupapa Māori approach to knowledge transfer within, and between, generations of whānau and hapū. Another important driving force behind this work is a need to express the actual practice of intergenerational trans-mission as evidence of the centrality of ako or Māori pedagogy in terms of raranga.
The research questions I pose, are based around the difference between, mōhiotanga, mātauranga, māramatanga and mahi within in a raranga and whatu context.
What is the importance of indigenous intergenerational knowledge transmission through raranga/whatu?
Is it possible to understand the skills and intricacies of an artefact that gives us knew, yet old knowledge from the expertise left by our kairaranga?
The creative component of this research includes as a feature the reproduction of a kete pūkoro, also known as a pututu, especially in the northern tribal dialects (Williams, 2005). The pūkoro is held in the the Otago Museum and the kairaranga has not been identified. The Ngai Tahu dialect emphasise this kete is a pūkoro (Dr J.Williams, personal communication, 2015) which is the term I utilise throughout this research as an acknowledgement to the kairaranga from the southern region of Otakau. A kete pūkoro is a finely woven kete which was used to squeeze the juice from the tutu berries (Beever, 1991). The pūkoro is the only known such taonga that exists and is so fragile that it‘s no longer exhibited. The fragility of the piece is prone to damage through touch, movement and light exposure, so is kept in a temperature controlled draw in the Otago Museum, Dunedin. The uniqueness of this piece of work is the construction, form and the function. The pūkoro sits at the centre of the practice for this research as an example of intergenerational knowledge transfer of the taonga. The raranga technique will be analyzed and the function and form will be replicated to understand more about the kairaranga through the making of the pūkoro. The artefact will be researched and analyzed considering every detail possible, documenting, and reflecting on the processes. Whilst the pūkoro is the centre piece that shows the refinement of knowledge of the kairaranga, it demonstrated the skills and ability to produce a taonga that could be used as a practical kete for sieving out the poisonous kernels of the tutu, only allowing the juice to be strained through it.
Why the pūkoro?
When I first came upon the pūkoro, it was only by osmosis. The pūkoro was stored away in a dark area, and I was attracted to the space where it was stored while viewing kete whakairo that were put out for display for me. I was the kaiako at Otago University for the Toi Onamata classes within Te Tumu, the Māori and Pacific studies Faculty. I arranged with the museum curator to view the kete whakairo in their collection.
I felt drawn to that part of the museum after feeling a strong sense of needing to see what was kept in the dark. I had a strong feeling and attraction to viewing what was kept in the dark, so I asked the curator if I could see what was kept in that space. I was told it was a very fragile kete made of harakeke which they considered was an un-usual shape and it was noted that it was a very old piece. and that the shape of it was unusual, and it was a very old. This made me more curious, as there was something particularly that I was alluring about me to this taonga.
When closely analysing the piece, I realised I could not see the commencement or completion. With closer inspection of the construction, it became more obvious to me, as a kairaranga that the skills and technical detail of horizontal and vertical twills of overlaying patterns used, were woven that way for a purpose.
From that first viewing, I was able to tell the curator, exactly what this artefact was used for, what material it was made out of and that the technical construction of the kete pūkoro was different from others I had viewed before.
It was this moment in time, that I had an epiphany, that this piece of work could tell a story of the unknown kairaranga. I decided right from that point, that I would try my best to bring to light the technical ability of the raranga weave and why it was constructed in such a way.
Like anything, further research needed to be done on the pūkoro, to understand the purpose of this fine piece of work. This was the impetus of my study. The questions I asked myself were:
Why was I attracted to this dark space? For me it was my wairuatanga, alluring me to a space with a deep sense that there was a reason I needed to be there at that time. It was that strong spiritual belief that enabled me to listen to that and to go into the space the pūkoro was being held.
How did I know and understand the construction of the kete pūkoro?. This was about my Mōhiotanga, using my own tacit knowledge, years of observation and passion to engage with a taonga left from a kairaranga of the past century.
What was the purpose of reconstructing this taonga? – This is about the mātauranga imbued in the construction of the Kete Pūkoro. It was to engage in further research to find out more detail beyond what I already knew.
How can I best share this knowledge and practice? – This is about Māramatanga, as I have been always taught, there is no point knowing a skill, and information if it is not shared.

year: 2022