title: Isolation of anaerobic, extremely thermophilic, sulphur metabolising archaebacteria from New Zealand hot springs

authors: Patel, B.K.C.

subjects: hot springs

abstract: Enrichments of New Zealand geo-thermal samples, initiated in anaerobic sulphur-containing media and incubated at temperatures above 85°C, yielded rod and coccal shaped organisms which possessed archaebacterial characteristics. Pure cultures were isolated and characterised. Five of the seven isolates, which were rod-shaped organisms and did not have an obligate requirement for sulphur respiration, were similar to Ther-moproteus sp. but had more neutral pH optima for growth. Three of these five Thermoproteus sp. were obligate heterotrophs, which has not previously been reported. The two coccal isolates had an obligate requirement for sulphur as an electron acceptor and were similar to Desulfurococcus sp. but again with more neutral pH optima for growth.

text: Isolation of anaerobic, extremely thermophilic, sulphur metabolising archaebacteria from New Zealand hot springs Enrichments of New Zealand geo-thermal samples, initiated in anaerobic sulphur-containing media and incubated at temperatures above 85°C, yielded rod and coccal shaped organisms which possessed archaebacterial characteristics. Pure cultures were isolated and characterised. Five of the seven isolates, which were rod-shaped organisms and did not have an obligate requirement for sulphur respiration, were similar to Ther-moproteus sp. but had more neutral pH optima for growth. Three of these five Thermoproteus sp. were obligate heterotrophs, which has not previously been reported. The two coccal isolates had an obligate requirement for sulphur as an electron acceptor and were similar to Desulfurococcus sp. but again with more neutral pH optima for growth.

year: 1986

title: Zooplankton communities in small Waikato lakes and ponds: are natural waters and farm dams the same?

authors: Le Quesne, Kelly Sarah

subjects: rural ponds

abstract: Ponds have been identified as biodiversity ‘hotspots’ that play an important role in supporting and maintaining biodiversity. In freshwater ecosystems, zooplankton are an essential trophic link between algae and fish, and some species act as biological indicators for aquatic system ‘health’. Most research pertaining to zooplankton biodiversity and community assemblages is skewed towards large lakes, reservoirs or urban ponds, while research on small ponds in rural environments is scarce. Consequently, the aim of my research was to examine and compare the biodiversity and community composition of zooplankton in natural ponds and dams in rural environments. To achieve this, 19 farm dams and 19 natural farm ponds in the Waikato region, New Zealand, were sampled for zooplankton in winter/spring (Aug-Sep 2018) and summer (Jan 2019). Environmental factors also were measured, including water temperature, dissolved oxygen, conductivity, water colour (gilvin), pH, chlorophyll-a, nutrient concentrations (total nitrogen and phosphorus), elevation, pond surface area and the number of waterbodies within a 2 km radius.

All ponds were eutrophic to hypertrophic, and genera typical of these environments, such as Brachionus, Keratella and Polyarthra, were common in both farm dams and natural ponds. Zooplankton species richness was similar among farm dams and natural ponds (20.7 and 22.4 species, respectively; t-test p = 0.406), although there was a lot of variation within each pond type. Temperature (stepwise linear regression R² = 0.26; p = 0.025) and pond surface area (stepwise linear regression R² = 0.23; p = 0.016) were significant predictors of species richness in natural ponds; however, no significant relationships could be found between the measured environmental variables and species richness for farm dams. Zooplankton community composition differed between farm dams and natural ponds (one-way ANOSIM p = 0.014). A SIMPER analysis indicated that crustaceans (e.g., Chydorus sp., Acanthocyclops robustus and Simocephalus vetulus) were generally more abundant in natural ponds than in farm dams, whereas rotifers (e.g., Polyarthra dolichoptera and Keratella tecta) were more abundant in farm dams than in natural ponds. A canonical correspondence analysis indicated that variation in zooplankton community composition among natural ponds was explained by dissolved oxygen concentration (p = 0.002) and conductivity levels (p = 0.020). In contrast, the community composition of zooplankton in farm dams could not be explained by any of the measured environmental variables. Two genera (Erignatha clastopis and Octotrocha speciosa) and one species (Cephalodella theodora) were recorded that had not previously been identified in New Zealand. In total, three non-indigenous species were recorded in 7% of farm dams and 2% of natural ponds studied.

My findings suggest that zooplankton communities differ between farm dams and natural ponds. Farm dams are primarily composed of a relatively unstructured subset of small, eurytopic and opportunistic zooplankton species (e.g., of Brachionus and Keratella). On the other hand, natural pond assemblages consisted of larger zooplankton species that are better adapted to the local conditions (e.g., Chydorus sp. and Simocephalus vetulus). This suggests natural ponds have had a longer period of time for more slowly dispersing species to colonise, whereas farm dams contain species that are capable of dispersing at much faster rates. Further, my results highlight that when examining environmental determinants of zooplankton community composition in water bodies across the landscape, natural and constructed ponds should be separated, as they appear to be structured by different variables. The prevalence of non-indigenous species in farm dams appears low relative to lakes and urban ponds in New Zealand, likely due to limited movement between ponds by humans. This suggests that these waterbodies are not acting as ‘stepping stones’ for non-indigenous species across rural landscapes. Overall, my research highlights the diverse taxa found in small agricultural ponds, and improves our knowledge and understanding of zooplankton communities in small natural and constructed ponds. Further, these findings emphasize the need for management and conservation of small water bodies, as they play a significant role in maintaining and supporting zooplankton communities (including rare species).

text: Zooplankton communities in small Waikato lakes and ponds: are natural waters and farm dams the same? Ponds have been identified as biodiversity ‘hotspots’ that play an important role in supporting and maintaining biodiversity. In freshwater ecosystems, zooplankton are an essential trophic link between algae and fish, and some species act as biological indicators for aquatic system ‘health’. Most research pertaining to zooplankton biodiversity and community assemblages is skewed towards large lakes, reservoirs or urban ponds, while research on small ponds in rural environments is scarce. Consequently, the aim of my research was to examine and compare the biodiversity and community composition of zooplankton in natural ponds and dams in rural environments. To achieve this, 19 farm dams and 19 natural farm ponds in the Waikato region, New Zealand, were sampled for zooplankton in winter/spring (Aug-Sep 2018) and summer (Jan 2019). Environmental factors also were measured, including water temperature, dissolved oxygen, conductivity, water colour (gilvin), pH, chlorophyll-a, nutrient concentrations (total nitrogen and phosphorus), elevation, pond surface area and the number of waterbodies within a 2 km radius.

All ponds were eutrophic to hypertrophic, and genera typical of these environments, such as Brachionus, Keratella and Polyarthra, were common in both farm dams and natural ponds. Zooplankton species richness was similar among farm dams and natural ponds (20.7 and 22.4 species, respectively; t-test p = 0.406), although there was a lot of variation within each pond type. Temperature (stepwise linear regression R² = 0.26; p = 0.025) and pond surface area (stepwise linear regression R² = 0.23; p = 0.016) were significant predictors of species richness in natural ponds; however, no significant relationships could be found between the measured environmental variables and species richness for farm dams. Zooplankton community composition differed between farm dams and natural ponds (one-way ANOSIM p = 0.014). A SIMPER analysis indicated that crustaceans (e.g., Chydorus sp., Acanthocyclops robustus and Simocephalus vetulus) were generally more abundant in natural ponds than in farm dams, whereas rotifers (e.g., Polyarthra dolichoptera and Keratella tecta) were more abundant in farm dams than in natural ponds. A canonical correspondence analysis indicated that variation in zooplankton community composition among natural ponds was explained by dissolved oxygen concentration (p = 0.002) and conductivity levels (p = 0.020). In contrast, the community composition of zooplankton in farm dams could not be explained by any of the measured environmental variables. Two genera (Erignatha clastopis and Octotrocha speciosa) and one species (Cephalodella theodora) were recorded that had not previously been identified in New Zealand. In total, three non-indigenous species were recorded in 7% of farm dams and 2% of natural ponds studied.

My findings suggest that zooplankton communities differ between farm dams and natural ponds. Farm dams are primarily composed of a relatively unstructured subset of small, eurytopic and opportunistic zooplankton species (e.g., of Brachionus and Keratella). On the other hand, natural pond assemblages consisted of larger zooplankton species that are better adapted to the local conditions (e.g., Chydorus sp. and Simocephalus vetulus). This suggests natural ponds have had a longer period of time for more slowly dispersing species to colonise, whereas farm dams contain species that are capable of dispersing at much faster rates. Further, my results highlight that when examining environmental determinants of zooplankton community composition in water bodies across the landscape, natural and constructed ponds should be separated, as they appear to be structured by different variables. The prevalence of non-indigenous species in farm dams appears low relative to lakes and urban ponds in New Zealand, likely due to limited movement between ponds by humans. This suggests that these waterbodies are not acting as ‘stepping stones’ for non-indigenous species across rural landscapes. Overall, my research highlights the diverse taxa found in small agricultural ponds, and improves our knowledge and understanding of zooplankton communities in small natural and constructed ponds. Further, these findings emphasize the need for management and conservation of small water bodies, as they play a significant role in maintaining and supporting zooplankton communities (including rare species).

year: 2019

title: Virtual hākari:  Sharing Māori culinary traditions in online communities

authors: Muru-Lanning, Charlotte

subjects: Kai Māori

abstract: For Māori, kai is a vital expression of identity, community, place and whakapapa. Traditionally, knowledge about kai is transmitted through customary community groupings and culturally embedded practices. However, with the rise of digital platforms, new spaces have emerged for Māori to gather and to share kai in virtual forms. 
This thesis observes how two Facebook groups – Kai Maori and KAI Basket NZ – operate as contemporary spaces for the transmission of Māori culinary knowledge and cultural identity. Kai Māori is considered alongside global studies of culinary traditions and understood through the notion of kai as whakapapa. The thesis addresses two core research questions: 1) How do Facebook groups contribute to an evolving concept of kai Māori? and 2) What kinds of relationships define these online kai communities? 
Guided by Māori data sovereignty (MDSov) principles, I observed interactions on both Facebook pages in two phases – one involving selective data collection over a twelve-month period from January to December 2024 the other involving systematic data collection over a four-week period from 10 December 2024 to 10 January 2025. The observation periods yielded 115 and 1293 posts respectively. A covert digital approach of ‘lurking’ was adopted as seeking prior consent may have affected the quality of the data and disrupted group dynamics. Lurking, as a method, sits uneasily alongside MDSov principles, particularly the principle of manaakitanga, requiring free, prior and informed consent. To address this I safeguarded the confidentiality of community members by seeking consent before reproducing content, removing group members’ names and excluding sensitive information. To analyse posts I used Ethnographic Content Analysis which allowed me to conduct a reflexive, iterative analysis of the posts in a way that was sensitive to the context in which the content was created.
These digital observations show that these groups serve as platforms for the transmission and innovation of kai Māori, encompassing edible components as well as the values enmeshed within these culinary traditions. Despite the mediated nature of these exchanges – where food is virtually consumed rather than physically shared, separate from traditional notions of community – these groups nurture meaningful connections among members, including those physically distant from their whenua. Through recipes, photos, stories, and commentary, the members of Kai Maori and KAI Basket NZ cultivate community identity and belonging via common cultural understandings, sharing of knowledge, a general spirit of sociality – and, importantly, a mutual love of kai.
I conceptualise these online spaces as virtual hākari, where the act of sharing virtual kai becomes an affirmation of identity and a form of cultural resistance. While online sharing may risk distancing kai practices and knowledge from traditional sites of transmission, the data suggests that these platforms may serve as conduits that encourage deeper cultural engagement offline. This thesis highlights the centrality of food in Māori cultural survival, sovereignty and resistance. In these digital spaces, kai Māori is not only celebrated but continually reimagined – reinforcing that to prepare, share and celebrate kai as Māori is to actively participate in the continuity of cultural identity.

text: Virtual hākari:  Sharing Māori culinary traditions in online communities For Māori, kai is a vital expression of identity, community, place and whakapapa. Traditionally, knowledge about kai is transmitted through customary community groupings and culturally embedded practices. However, with the rise of digital platforms, new spaces have emerged for Māori to gather and to share kai in virtual forms. 
This thesis observes how two Facebook groups – Kai Maori and KAI Basket NZ – operate as contemporary spaces for the transmission of Māori culinary knowledge and cultural identity. Kai Māori is considered alongside global studies of culinary traditions and understood through the notion of kai as whakapapa. The thesis addresses two core research questions: 1) How do Facebook groups contribute to an evolving concept of kai Māori? and 2) What kinds of relationships define these online kai communities? 
Guided by Māori data sovereignty (MDSov) principles, I observed interactions on both Facebook pages in two phases – one involving selective data collection over a twelve-month period from January to December 2024 the other involving systematic data collection over a four-week period from 10 December 2024 to 10 January 2025. The observation periods yielded 115 and 1293 posts respectively. A covert digital approach of ‘lurking’ was adopted as seeking prior consent may have affected the quality of the data and disrupted group dynamics. Lurking, as a method, sits uneasily alongside MDSov principles, particularly the principle of manaakitanga, requiring free, prior and informed consent. To address this I safeguarded the confidentiality of community members by seeking consent before reproducing content, removing group members’ names and excluding sensitive information. To analyse posts I used Ethnographic Content Analysis which allowed me to conduct a reflexive, iterative analysis of the posts in a way that was sensitive to the context in which the content was created.
These digital observations show that these groups serve as platforms for the transmission and innovation of kai Māori, encompassing edible components as well as the values enmeshed within these culinary traditions. Despite the mediated nature of these exchanges – where food is virtually consumed rather than physically shared, separate from traditional notions of community – these groups nurture meaningful connections among members, including those physically distant from their whenua. Through recipes, photos, stories, and commentary, the members of Kai Maori and KAI Basket NZ cultivate community identity and belonging via common cultural understandings, sharing of knowledge, a general spirit of sociality – and, importantly, a mutual love of kai.
I conceptualise these online spaces as virtual hākari, where the act of sharing virtual kai becomes an affirmation of identity and a form of cultural resistance. While online sharing may risk distancing kai practices and knowledge from traditional sites of transmission, the data suggests that these platforms may serve as conduits that encourage deeper cultural engagement offline. This thesis highlights the centrality of food in Māori cultural survival, sovereignty and resistance. In these digital spaces, kai Māori is not only celebrated but continually reimagined – reinforcing that to prepare, share and celebrate kai as Māori is to actively participate in the continuity of cultural identity.

year: 2025