title: Assessment of trophic state change and lake health in selected lakes of the Auckland region based on zooplankton assemblages: 2012-2019

authors: Duggan, Ian C.

abstract: This report provides an assessment of eight natural lakes in the Auckland region, from zooplankton samples collected between 2012 and late 2019 at a frequency of six to eight samples per year. From these samples, the lakes have been assessed to establish their trophic state, the proportion of nonnative zooplankton species, and the proportion of crustacean zooplankton relative to rotifers. 

Inferred trophic states of the lakes based on zooplankton composition has been generally ranked in a similar manner over time; of the lakes sampled over the entire period, Lake Tomarata typically had the best inferred water quality (generally as mesotrophic, though late in the study it sat near the eutrophic boundary). The median Trophic Level Index (TLI) based on zooplankton for this lake was 3.5 between 2015 and 2019. Lake Whatihua, only sampled from late-2017, was also assessed to contain species typical of mesotrophic conditions (median TLI = 3.4). For the remaining lakes, median TLI values based on zooplankton composition between 2015 and 2019 were; Rototoa 3.5 (mesotrophic), Wainamu 4.0, Pupuke 4.3 (both eutrophic) and Kuwakatai 5.2 (supertrophic; sampling ceased in August 2017). Lakes Kereta and Spectacle were not assessed during the 2015- 2019 time period. 

Lake Pupuke rapidly declined in water quality in 2019, to have hypertrophic assessments at the end of the study; this is consistent with reported high chlorophyll a concentrations at this time. Lake Tomarata was assessed to have declining water quality based on zooplankton composition, in common with traditional TLI assessments. However, this lake was assessed to have higher water quality overall, and to diverge in assessments by 1.2 TLI units; this may in part be due to elevated TN concentrations in this lake, not reflected in concentrations of TP or chlorophyll a, which may unduly affect traditional TLI assessments for this lake. The other long-term lakes, Waimanu, Pupuke and Rototoa, all has assessments within 0.5 TLI units when comparing the traditional and rotifer inferred TLI systems. 

The proportion of non-native species and the proportion of crustacean zooplankton relative to rotifers both showed promise as monitoring tools for the Auckland lakes. Two non-native species were recorded in the lakes, with various levels of dominance. Daphnia galeata was recorded in all of the monitored lakes, while Skistopiaptomus pallidus was recorded in Lake Kereta only. For the proportions of non-native species, Lake Tomarata was least affected, with samples comprising 4.9% non-native species on average. Data from 2012 and 2013 indicated that the overall relative abundances of the calanoid copepod Skistodiaptomus pallidus in Lake Kereta were far lower than they were in the year’s immediately following invasion in late 2008. No new non-native species were recognised in the monitored lakes during this survey, although an unusual occurrence of the copepod Boeckella propinqua was recorded in Lake Whatihua; this species has otherwise been found from natural lakes only in the central North Island, although has been recorded previously in Auckland dams. 

On average, larger crustaceans dominated over the smaller rotifers in all of the Auckland lakes monitored. Lake Rototoa was the least crustacean dominated (53%), followed by lakes Tomarata (58%), Kereta (68%), Spectacle (78%), Whatihua (79%), Wainamu (81%), Pupuke (88%), and Kuwakatai (95%) was the most crustacean dominated. Lake Wainamu appears to have reduced proportions of crustaceans between 2018 and 2019 relative to the 2012 to 2017 period, which may indicate this lake is undergoing a change in its trophic ecology; control of pest fish ceased in this lake in 2015, including of European perch (Perca fluviatilis), which may be reducing the importance of larger, more visible crustaceans.

text: Assessment of trophic state change and lake health in selected lakes of the Auckland region based on zooplankton assemblages: 2012-2019 This report provides an assessment of eight natural lakes in the Auckland region, from zooplankton samples collected between 2012 and late 2019 at a frequency of six to eight samples per year. From these samples, the lakes have been assessed to establish their trophic state, the proportion of nonnative zooplankton species, and the proportion of crustacean zooplankton relative to rotifers. 

Inferred trophic states of the lakes based on zooplankton composition has been generally ranked in a similar manner over time; of the lakes sampled over the entire period, Lake Tomarata typically had the best inferred water quality (generally as mesotrophic, though late in the study it sat near the eutrophic boundary). The median Trophic Level Index (TLI) based on zooplankton for this lake was 3.5 between 2015 and 2019. Lake Whatihua, only sampled from late-2017, was also assessed to contain species typical of mesotrophic conditions (median TLI = 3.4). For the remaining lakes, median TLI values based on zooplankton composition between 2015 and 2019 were; Rototoa 3.5 (mesotrophic), Wainamu 4.0, Pupuke 4.3 (both eutrophic) and Kuwakatai 5.2 (supertrophic; sampling ceased in August 2017). Lakes Kereta and Spectacle were not assessed during the 2015- 2019 time period. 

Lake Pupuke rapidly declined in water quality in 2019, to have hypertrophic assessments at the end of the study; this is consistent with reported high chlorophyll a concentrations at this time. Lake Tomarata was assessed to have declining water quality based on zooplankton composition, in common with traditional TLI assessments. However, this lake was assessed to have higher water quality overall, and to diverge in assessments by 1.2 TLI units; this may in part be due to elevated TN concentrations in this lake, not reflected in concentrations of TP or chlorophyll a, which may unduly affect traditional TLI assessments for this lake. The other long-term lakes, Waimanu, Pupuke and Rototoa, all has assessments within 0.5 TLI units when comparing the traditional and rotifer inferred TLI systems. 

The proportion of non-native species and the proportion of crustacean zooplankton relative to rotifers both showed promise as monitoring tools for the Auckland lakes. Two non-native species were recorded in the lakes, with various levels of dominance. Daphnia galeata was recorded in all of the monitored lakes, while Skistopiaptomus pallidus was recorded in Lake Kereta only. For the proportions of non-native species, Lake Tomarata was least affected, with samples comprising 4.9% non-native species on average. Data from 2012 and 2013 indicated that the overall relative abundances of the calanoid copepod Skistodiaptomus pallidus in Lake Kereta were far lower than they were in the year’s immediately following invasion in late 2008. No new non-native species were recognised in the monitored lakes during this survey, although an unusual occurrence of the copepod Boeckella propinqua was recorded in Lake Whatihua; this species has otherwise been found from natural lakes only in the central North Island, although has been recorded previously in Auckland dams. 

On average, larger crustaceans dominated over the smaller rotifers in all of the Auckland lakes monitored. Lake Rototoa was the least crustacean dominated (53%), followed by lakes Tomarata (58%), Kereta (68%), Spectacle (78%), Whatihua (79%), Wainamu (81%), Pupuke (88%), and Kuwakatai (95%) was the most crustacean dominated. Lake Wainamu appears to have reduced proportions of crustaceans between 2018 and 2019 relative to the 2012 to 2017 period, which may indicate this lake is undergoing a change in its trophic ecology; control of pest fish ceased in this lake in 2015, including of European perch (Perca fluviatilis), which may be reducing the importance of larger, more visible crustaceans.

year: 2021

title: Isolation, Characterization and Synthesis of a Phenyl-substituted Pyrrole Isolated from the Flavonoid Fraction of Mānuka Honey

authors: Chan, Ching Wan

subjects: Mānuka Honey

abstract: Compound 1, which occurs in the flavonoid fraction of mānuka honey and showed a statistical correlation with the non-peroxide antibacterial activity of the honeys, was extracted from fifteen kilograms of mānuka honey using Amberlite XAD-2 resin and liquid-liquid extraction, and isolated by a combination of Sephadex-LH20 column chromatography and HPLC. Characterization of 1 was achieved by one and 2D- 1H and 13C NMR spectroscopy and GC-MS and 1 was identified as 2-formyl-5-(2-methoxyphenyl)-pyrrole. In addition to 1, two other non-flavonoids were isolated from the flavonoid fraction and their identities confirmed as caffeic acid and p-coumaric acid. Synthesis of 9 (3-hydroxy-1-(2-methoxyphenyl)-3-(oxazol-4-yl) propan-1-one), an intermediate in the route to 1, gave a yield of 67.5% as a pale yellow crystals after crystallization from CH2Cl2/hexane. Synthesis of 1 from 9 only resulted in barely traceable amount of 1. The dominant product after recrystallization from CH2Cl2/hexane was 10 ((E)-1-(2-methoxyphenyl)-3-(oxazol-4-yl)prop-2-en-1-one) which was the dehydrated analogue of 9. The synthesis of 1 was repeated. The product mixture was fractionated on a silica gel column, followed by two cycles of preparative layer chromatography applied to the fractions which contained 1 and yield 0.36 mg of 1 (0.00179 mmol, 0.2%).

text: Isolation, Characterization and Synthesis of a Phenyl-substituted Pyrrole Isolated from the Flavonoid Fraction of Mānuka Honey Compound 1, which occurs in the flavonoid fraction of mānuka honey and showed a statistical correlation with the non-peroxide antibacterial activity of the honeys, was extracted from fifteen kilograms of mānuka honey using Amberlite XAD-2 resin and liquid-liquid extraction, and isolated by a combination of Sephadex-LH20 column chromatography and HPLC. Characterization of 1 was achieved by one and 2D- 1H and 13C NMR spectroscopy and GC-MS and 1 was identified as 2-formyl-5-(2-methoxyphenyl)-pyrrole. In addition to 1, two other non-flavonoids were isolated from the flavonoid fraction and their identities confirmed as caffeic acid and p-coumaric acid. Synthesis of 9 (3-hydroxy-1-(2-methoxyphenyl)-3-(oxazol-4-yl) propan-1-one), an intermediate in the route to 1, gave a yield of 67.5% as a pale yellow crystals after crystallization from CH2Cl2/hexane. Synthesis of 1 from 9 only resulted in barely traceable amount of 1. The dominant product after recrystallization from CH2Cl2/hexane was 10 ((E)-1-(2-methoxyphenyl)-3-(oxazol-4-yl)prop-2-en-1-one) which was the dehydrated analogue of 9. The synthesis of 1 was repeated. The product mixture was fractionated on a silica gel column, followed by two cycles of preparative layer chromatography applied to the fractions which contained 1 and yield 0.36 mg of 1 (0.00179 mmol, 0.2%).

year: 2011

title: Listening to the Winds of Change: Assessing culturally responsive and relational pedagogy

authors: Thin-Rabb, Polly

subjects: Culturally responsive and relational pedagogy

abstract: This thesis examines how the Rongohia te Hau tools were used to capture a snapshot of the extent that culturally responsive and relational pedagogies were occurring within classrooms in two English-medium secondary schools in Aotearoa, New Zealand. In this study, school leaders used Rongohia te Hau to measure changes in the educational experiences of Māori learners over twelve to eighteen-months, to prioritise next steps in addressing the educational inequities that were evident. 

With the contribution of teachers, leaders and kaitoro (Kia Eke Panuku facilitators), this research investigates the purpose and place of Rongohia te Hau within the Kia Eke Panuku professional learning and development context. It also presents and discusses the pedagogical shifts that occurred in these two schools over the period of this research, as evidenced by quantitative and qualitative Rongohia te Hau data. Furthermore, the learning implications that arose out of this research are analysed to help generate new questions and considerations, to enable continuing conversations for these schools, other schools, professional learning and development providers and researchers.

text: Listening to the Winds of Change: Assessing culturally responsive and relational pedagogy This thesis examines how the Rongohia te Hau tools were used to capture a snapshot of the extent that culturally responsive and relational pedagogies were occurring within classrooms in two English-medium secondary schools in Aotearoa, New Zealand. In this study, school leaders used Rongohia te Hau to measure changes in the educational experiences of Māori learners over twelve to eighteen-months, to prioritise next steps in addressing the educational inequities that were evident. 

With the contribution of teachers, leaders and kaitoro (Kia Eke Panuku facilitators), this research investigates the purpose and place of Rongohia te Hau within the Kia Eke Panuku professional learning and development context. It also presents and discusses the pedagogical shifts that occurred in these two schools over the period of this research, as evidenced by quantitative and qualitative Rongohia te Hau data. Furthermore, the learning implications that arose out of this research are analysed to help generate new questions and considerations, to enable continuing conversations for these schools, other schools, professional learning and development providers and researchers.

year: 2017