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Christchurch shallow groundwater quality survey dataset
Get PDFShallow groundwater quality and level across the low-lying coastal city of Christchurch, New Zealand were surveyed at a high spatial resolution (1.3 piezometers/km²) in the spring of 2020. The groundwater quality parameters recorded across 99 piezometers include specific conductance, temperature, pH, and dissolved oxygen, following the pumping of approximately three bore volumes. Additionally, 27 out of 99 piezometers were analysed for chloride concentration and alkalinity as calcium carbonate. This dataset is useful to explore shallow groundwater conditions and how these might impact co-existing subsurface infrastructure and ecosystems. Furthermore, this dataset provides a valuable point of comparison against future changes, for example due to increased seawater intrusion, pollution events, or groundwater level rise
Natural history of retinal degeneration in ovine models of CLN5 and CLN6 neuronal ceroid lipofuscinoses
Get PDFNeuronal ceroid lipofuscinoses (NCL; Batten disease) are a group of inherited neurodegenerative diseases with a common set of symptoms including cognitive and motor decline and vision loss. Naturally occurring sheep models of CLN5 and CLN6 disease display the key clinical features of NCL, including a progressive loss of vision. We assessed retinal histology, astrogliosis, and lysosomal storage accumulation in CLN5 affected (CLN5 −/−) and CLN6 affected (CLN6 −/−) sheep eyes and age-matched controls at 3, 6, 12, and 18 months of age to determine the onset and progression of retinal pathology in NCL sheep. The retina of CLN5 −/− sheep shows progressive atrophy of the outer retinal layers, widespread gliosis, and accumulation of lysosomal storage in retinal ganglion cells late in disease. In contrast, CLN6 −/− retina shows significant atrophy of all retinal layers, progressive gliosis, and earlier accumulation of lysosomal storage. This study has highlighted the differential vulnerability of retinal layers and the time course of retinal atrophy in two distinct models of NCL disease. This data will be valuable in determining potential targets for ocular therapies and the optimal timing of these therapies for protection from retinal dysfunction and degeneration in NCL
Contrasting geophysical signatures of a relict and an intact Andean rock glacier
Get PDFIn semi-arid Chile, rock glaciers cover more surface area than glaciers and are potentially important water reserves. To understand their current and future hydrological role, it is necessary to characterize their internal structure (e.g. internal boundaries and ice, air, water and rock content). In this study, we present the results and interpretations of profiles of electrical resistivity and refraction seismic tomography collected on two contrasting rock glaciers in the Chilean Andes located at the headwaters of the Elqui River within the Estero Derecho nature reserve. These geophysical measurements are interpreted both independently and jointly through a scheme of petrophysical four-phase inversion. These first in situ measurements in Estero Derecho confirm that El Ternero (intact rock glacier) contains a significant volume of ground ice, while El Jote contains little to no ice (relict rock glacier). Within our study, we highlight the strong differences in the geophysical responses between intact and relict rock glaciers and propose a diagnostic model that differentiates between them
Regression-based gap-filling methods show air temperature reductions and wind pattern changes during the 2019 total eclipse in Chile
Get PDFSingular disruptive events like solar eclipses affect the measured values of meteorological variables at the earth’s surface. To quantify such an impact, it is necessary to estimate what value the parameter would have taken had the event not occurred. We design and compare several methods to perform such an estimate based on longer observational timeseries from individual meteorological surface stations. Our methods are based on regularised regressions (including a Bayesian variant) and provide both a point an associated error estimate of the disruptive event’s impact. With their help, we study the effect of the total solar eclipse of July 2nd, 2019, in the Coquimbo Region of Chile, on near-surface air temperatures and winds. The observational data used have been collected by the meteorological surface station network of the Centro de Estudios Avanzados en Zonas Áridas (CEAZA). Most stations inside the eclipse’s umbra registered a temperature drop of 1–2 °C, while the most extreme estimated temperature drop surpassed 6 °C. The presence of an ‘eclipse cyclone’ can neither be proven nor refuted. Application of the regression methods to other comparable problems like volcanic eruptions, forest fires, or simply gap filling of observational data, are conceivable
Effects of UV-B and water deficit on aroma precursors in grapes and flavor release during wine micro-vinification and consumption
Get PDFUV-B radiation and water availability can affect amino acids(AAs) concentration in berries, resulting in the evolution of aroma compounds during alcoholic fermentation. This study investigated the effects of UV-B exposure and water availability on wine aroma compounds in Pinot noir, focusing on the role of AAs in the process.Enhanced UV-B radiation significantly decreased total AA concentrations and most individual AAs in berries and wines, while water deficit increased some individual AAs in wines. Higher alcohols, fatty acids, esters, monoterpenes, and C₁₃-norisoprenoids were affected by UV-B interaction with water deficit in wines. These results suggested individual or combined UV-B exposure and water deficit had direct effects on fruit AAs, leading to significant differences in some wine aroma compounds
Decision-making framework for construction clients in selecting appropriate procurement route
Get PDFProcurement decision-making is a crucial determinant of project success. Although several objective, stage-based models have been proposed to guide clients’ procurement choices, little emphasis has been made on the subjective nature of construction clients. Recognizing the role of clients’ experiences in justifying procurement routes, this study develops a decision-making framework that is capable of guiding construction clients in making informed procurement choices. Adopting a mixed-method approach, comprising semi-structured interviews and multi-objective optimization, relevant procurement options were appraised based on clients’ specifications and project deliverables. The lived experiences of construction clients and the importance they attach to pre-defined selection rating criteria were subsequently evaluated, using a template that enables clients to prioritize procurement methods for different project types. The resultant framework offers a holistic, practical, and collaborative procurement selection process that promotes the efficient delivery of construction projects by reducing the cost overrun and delays associated with uninformed client decisions in construction procurement
Soil biogeochemistry and the benefits of grasses as companion plants : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
Get PDFIntercropping and other forms of mixed cropping are both widely used and beneficial in many agricultural systems. One of the best-known examples is the grass-clover production model in pastures, in which nitrogen-fixation by symbiotic bacteria (e.g. Rhizobium spp.) benefits the grass as well as the host species of clover (Trifolium spp.) or other legume species. This is one example of transgressive overyielding, which refers to situations when the yield of two species growing together exceeds the yield of either of the species growing individually on the same area of land. This doctoral study aimed to investigate the benefits of companion plants in terms of soil biogeochemistry, focusing particularly on species that are companion plants to grasses. Literature is reviewed of plant species competition and co-existence, and rhizosphere biogeochemistry, primarily in the context of pastoral grasslands in the New Zealand High Country. The research project includes an investigation of whether there are nutritional benefits to nitrogen (N) -fixing plants when they grow in combination with grasses, rather than this being simply a relationship that involves spillover of nitrogen from legumes to grasses. This is extended to studies of phosphorus (P) -mobilizing plants and grasses, to investigate whether grasses provide reciprocal nutrients to cluster-rooted plants in the Proteaceae. The hypothesis underlying this study was that rhizosphere processes in grasses may be more adept than clovers at exploiting key trace elements in soils, and that these trace elements can be exchanged for N or P, thus also providing an explanation for species coexistence.
Practical investigations consisted of pot experiments, a transplanted-soil core mesocosm experiment and field sampling, primarily concerned with nutrient deficient soils. This experimental work analysed the effects of different species combinations on (i) yield and (ii) plant and soil nutrient status (macronutrients and trace elements). Plant species combinations included both exotic and native species of grasses and legumes. The work was partly carried out on the Lincoln University Campus and at Mt. Grand Station, a university-owned high country pastoral farm in Hawea, Central Otago, from 2019 – 2022, with funding support from the Miss E.L. Hellaby Indigenous Grasslands Research Trust.
The results showed that grasses played a critical role in acquisition of soil nutrients when they were growing with companion legumes or proteas in degraded soil. I found that legumes contained more nutrients (e.g. P, potassium sulphur, molybdenum and boron) when they were growing with grasses. Both native tussock grasses and exotic pasture grasses had significant positive impacts on native and exotic legumes in terms of nutrient uptake of a range of elements including Nitrogen and Sulfur. Both legumes and grasses benefited from growing together. Cluster-rooted species of Proteacea and grasses were found to have higher foliar concentrations of nutrients when they were growing together.
The findings of this research provide evidence of facilitation between plant species with contrasting root systems when they are growing together in terms of procurement of key plant nutrients. Combinations of species can better exploit soil nutrients under conditions where fertility is constrained. This work is interpreted in the context of pasture production systems, protection of native biodiversity and land sharing by exotic and native species in the New Zealand High Country.
The thesis is presented as an introduction to the study, a broad literature review, the inclusion of three published papers 1-3, one recently-submitted manuscript 4, a chapter describing additional work carried out during the PhD study, and a chapter containing the interpretive discussion and conclusions
Community perception of animal-based urban agriculture within city greenspaces of the Global North: A survey of residents near Cornwall Park, New Zealand
Get PDFThe ability of cities worldwide to feed themselves is of increasing concern to Urban Planning and Design professions. In recent years, interest in reintegrating agricultural production back into cities of the Global North has grown, particularly with regard to plant-based urban agriculture. Research focused on animal-based urban agriculture however has been notably absent from the literature and case studies set within cities of the Global North. This study aims to contribute to this emerging area of research and seeks to better understand the enablers and barriers to integrating grazing animals within urban greenspace from a ‘neighbor’ perspective. This paper presents survey responses from residents living around Cornwall Park, an urban greenspace in Aotearoa New Zealand’s largest city, Tāmaki Makaurau Auckland, that integrates a working sheep and beef farm as part of the 172 ha urban greenspace. Findings revealed that the grazing animals were highly valued by the neighboring community with 99% of respondents feeling ‘positive’ towards the inclusion of grazing animals as part of the public park. Our findings have implications for cities of the Global North considering the reintegration of animal-based urban agriculture, providing support for decision-making when defining policies for enabling animal-based agriculture within public greenspace
Covenants - good or bad? The use of covenants in residential housing development and the potential impacts for future land use : A dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Planning at Lincoln University
Get PDFThis paper discusses the use of covenant land use controls for residential housing developments. The extent to which covenants exert control over the overall design outcomes of residential subdivisions. How land use control through covenants is likely to impact the incoming legislation for the National Policy Statement on Urban Development and Medium Density Residential Standards for Territorial Authorities in the future. Previous research has looked at how covenants have created affordability issues due to aspects such as minimum floor area. This research used a case study approach and data analysis of covenant documents for the Selwyn District as well as interviews and questionnaires conducted with developers, Council Planners, and the Selwyn District Council Planning Department. This provided an overall perspective of covenant use for residential housing developments. The key findings of this study are firstly that covenants are a private developer tool that is used to create a high level of consistency across the whole of the subdivision. This research also found that covenants are developer driven, and the specific clauses within the covenants themselves can prevent development further than what is stipulated within the covenant documents. The research identified that the use of covenants on burdened land could have implications in carrying out the key objectives of the National Policy Statement on Urban Development and the Medium Denisty Residential Standards. However, this is dependent to the clauses in the covenant documents themselves
Targeted selective treatment with anthelmintic for New Zealand dairy heifers
No full textWe investigated whether measurement of live weight gain (LWG) could be used to deliver targeted selective treatment (TST) with anthelmintic that maintained target live weight (LW) while reducing anthelmintic use. Dairy heifers (n = 546) from four commercial, seasonal calving, pastoral New Zealand dairy herds in the Canterbury region of New Zealand were recruited to compare effects of TST, against suppressive treatment (ST), on LW and LWG in their first year at pasture. Animals were enrolled at weaning (December) and weighed ± anthelmintic treatment every month until May and then in August and September, pre-mating in October. All ST calves were treated every month with an oral anthelmintic at 1 mL/5 kg LW, delivering 0.2 mg abamectin, 8 mg levamisole and 4.5 mg oxfendazole/kg LW, (Control). TST calves received the same anthelmintic at the same time but only if either their individual LWG fell below a pre-specified, time altered, breed specific target for that group (Group target) or if their individual LWG fell below an individual, time altered target for that individual (Individual target). Faecal egg count (FEC) and serum IgA OD levels were recorded from a sample of calves throughout the study. Compared to ST, anthelmintic use was halved in both TST groups (P 200 EPG grew more slowly in the autumn (P < 0.001), but more quickly in the winter (P < 0.001). FEC and IgA OD levels were consistent with levels of parasitism sufficient to impact LWG, but there was no evidence for differences between treatment groups. Sensitivity and specificity of LW and LWG as predictors of reaching target weight varied month-on-month but these results suggest monthly LWG and LW were poor indicators for AHC treatment. In conclusion, TST can be effective in reducing anthelmintic use and maintaining group level performance. LW and LWG sensitivity was 57-85 % and 66-93 %; specificity 38-83 % and 32-79 %