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The marble statue of Antarctic explorer Captain Robert Falcon Scott fell from its plinth in the 2011 earthquake in Canterbury, New Zealand. The statue, carved by his wife the sculptor Kathleen Scott, broke into two pieces. The subsequent conservation treatment to provide resilience against future earthquakes was not one that had been carried out previously on an historic statue. This paper discusses the treatment planning and treatment of the statue. It reflects on the people that inspired, created, commissioned and use the memorial, providing meaning and purpose for it. The paper considers how the conservation treatment was guided by these voices, and the voices of those who represent them today, in order to develop a treatment that is fit for purpose and reflects the spirit of the original site. [ABSTRACT FROM AUTHOR]

The paper analyses sources of delay in developing environmental interventions to address overallocation of groundwater and water quality degradation for Te Waihora/Lake Ellesmere, a coastal lake in the Canterbury Region of New Zealand. The analysis highlighted the length of time required to collect the science to understand an issue and to formulate and implement policy responses. It also identified delays due to scientific uncertainty, scientific controversies, disregarding science, decision processes, and the response time of the natural system. The absence of clear policy approaches and environmental outcomes in order to implement environmental legislation was a significant source of delay. Delays in implementing environmental interventions led to loss of natural capital with groundwater overallocation reducing flows in groundwater-fed streams and freshwater inflows to the lake, and land use intensification degrading groundwater, groundwater-fed streams, and lake water quality. The extent of development beyond sustainable limits during these delays may have permanently compromised the ability to implement comprehensive environmental interventions. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate whether stakeholders' understanding of natural resource decision-making was influenced by the form that visualization of environmental changes were presented, using Te Waihora/Lake Ellesmere, New Zealand as a case study. An interactive visualization (I-Vis) tool "ElleVis," developed by (Otinpong 2013), shows the effects of different water levels on the flora and fauna living in and around the lake. An experimental design was used in which 40 stakeholders were randomly assigned to a presentation of this information using I-Vis or a non-interactive paper form of the visualization (NI-Vis). While stakeholders in both groups significantly improved their understanding of information, stakeholders presented with information using I-Vis made a statistically significant greater gain in understanding than those presented information using NI-Vis (t(38)=2.663, p<.05). Semi-structured discussions with participants confirmed the importance stakeholders placed on the interactive nature of the visualizations. The findings inform discussions about how I-Vis tools might contribute to an understanding of environmental management situations where contested resources and/or a multiplicity of interests are involved. [ABSTRACT FROM AUTHOR]

This paper examines Indigenous property development, drawing on research into the development of treaty settlement lands in Manitoba, Canada, and Canterbury, New Zealand. It highlights two contradicting ways of understanding this work: Indigenous peoples as self-determining, with authority to develop their own urban planning approaches, and Indigenous peoples as conventional property developers, subject to the same rules as any other private interest. This contradiction is used to expose a need for alternative, decolonial ways of understanding relationships between the 'planner' and the 'planned', grounded in the recognition of overlapping governance roles and responsibilities which Indigenous peoples are now (re)claiming in the urban environment. [ABSTRACT FROM AUTHOR]

This paper presents a generalised velocity model construction methodology, its computational implementation, and application in the construction of a New Zealand Velocity Model (NZVM2.0) for use in physics-based broadband ground motion simulation. The methodology utilises multiple datasets spanning different length scales, which is enabled via the use of modular subregions, geologic surfaces, and parametric representations of crustal velocity. A number of efficiency-related workflows to decrease the overall computational construction time are employed, while maintaining the flexibility and extensibility to incorporate additional datasets and refined velocity parameterisations as they become available. The methodology and computational implementation processes are then applied for development of a New Zealand Velocity Model (NZVM2.0) for use in broadband ground motion simulation. The model comprises explicit representations of the Canterbury, Wellington, Nelson-Tasman, Kaikōura, Marlborough, Waiau, Hanmer and Cheviot sedimentary basins embedded within an existing regional travel-time tomography-based velocity model for the shallow crust. [ABSTRACT FROM AUTHOR]

The incidence of early-onset colorectal cancer (EOCRC) is increasing. International guidelines state that treatment should not differ from that of older patients. Several studies have shown that patients under 50 years are receiving more aggressive treatment, without any survival benefit. We aim to determine if treatment for stages 2 and 3 EOCRC differs from those of late-onset colorectal cancer (LOCRC) patients. This was a retrospective, population-based, cohort study of the treatment patterns of patients diagnosed with colorectal cancer in Canterbury, New Zealand, from 2010 to 2021 age <50 years, compared to those aged 60–74 years. A total of 3263 patients were diagnosed with CRC between 2010 and 2021. Following exclusions, we identified 130 EOCRC and 668 LOCRC patients. Stage 2 EOCRC patients are more likely to be offered adjuvant chemotherapy (p = <0.001). Furthermore, EOCRC patients with either stage 2 or 3 disease are more likely to receive multi-agent therapy (p = <0.01), without any associated increase in survival. EOCRC patients are given more adjuvant chemotherapy, without a corresponding improvement in outcomes, highlighting a potential for increased treatment-related harms, particularly in stage 2 disease. Clinicians should be mindful of these biases when treating young cancer patients and need to carefully consider treatment-related harms. [ABSTRACT FROM AUTHOR]

In 1995, a dynamic cadastre, based on a dynamic geodetic datum, was proposed for New Zealand to recognise that all cadastral boundaries are in motion. Subsequently New Zealand implemented a semi-dynamic geodetic datum which is accompanied by a deformation model. In 2010 and 2011, the Canterbury region in the South Island of New Zealand was subjected to a sequence of earthquakes that resulted in some boundaries being ruptured by up to 4 metres. A set of localised deformation models was developed to model the seismic movements. The implementation of these models and their accuracy are addressed in this paper. [ABSTRACT FROM PUBLISHER]

Wastewater treatment plants (WWTPs) have been identified as a source of microplastics, an emerging contaminant class of increasing concern, to the environment. Three WWTPs in the Canterbury region, New Zealand, were sampled bi-monthly from winter (June) to summer (December), to assess the variability of the abundance, morphology and polymer type of microplastics present over time. Microplastics were isolated from effluent via wet-sieving (300 μm and 1 mm) and wet peroxide oxidation (WPO) digest, and the polymer types determined using micro-Fourier-Transform Infrared Spectroscopy (μ-FTIR). Confirmed microplastics were detected at an average concentration of 1.3 ± 0.6 particles/L in effluent, with fragments comprising 58% of all morphotypes. Dominant polymer types detected were polyester, polyethylene, and polypropylene (26%, 22%, and 15%, respectively). The results of this study were comparable with those reported in international studies. An estimated 2.4 × 105 microplastics enter the receiving coastal environment daily from the discharge of effluent from the three WWTPs studied. No trends in microplastic concentration, morphotype and polymer type were observed in effluent samples from each WWTP, suggesting a common and continual source of microplastics into WWTPs. Further sampling is required to identify the factors that determine the variability of microplastics in WWTP influents and effluents. [ABSTRACT FROM AUTHOR]

The Hundalee Fault forms part of the southeastern margin of the 2016 Kaikōura Earthquake rupture zone. Its late Quaternary activity and structural character may offer insights to fault interrelationships associated with the 2016 rupture. Mapping of the Hundalee Fault revealed several pre-existing fault scarps. Trenching of a scarp across a fluvial terrace together with radiocarbon dating shows the occurrence of at least two, probably three, surface ruptures since 3.5 ka. The scarp records about 2.5 m of reverse-sense vertical deformation, mostly folding, of which ∼0.6 m occurred in 2016, along with subordinate sinistral slip. Fluvial terrace ages inferred from geomorphological relationships, together with the trenching results, indicate a long-term vertical slip rate of 0.2–0.4 mm/yr since at least 30 ka. Geological data indicate a relatively recently surface emergence of the Hundalee Fault from beneath a fault propagation fold. The 2016 Hundalee Fault rupture is interpreted as a break-out from an extensive blind thrust fault, whose motion triggered predominantly contractional rupture of an array of steeper near-surface faults. The thrust is hypothesised as having provided linkage in the 2016 rupture between the predominantly strike-slip ruptures of The Humps Fault to the southwest and the Kekerengu Fault to the northeast. [ABSTRACT FROM AUTHOR]

Insufficient water for irrigation is a common problem in the Canterbury Region of New Zealand. Farmers have the option of applying for resource consent or joining a community irrigation scheme to take water. Water supply becomes more problematic during drought seasons as farmers must adhere to water restrictions imposed by the water authority. To deal with this problem, we developed an agent-based irrigation management system that can be used by farmers to calculate the ideal crop water needs on individual farms, which is particularly useful during periods of water scarcity. During water scarcity, most farms will have shortages of water. However, it is possible that there are farmers who will have excess water that could be distributed to those who need it. By doing this, farmers with excess water can make more profit and those who do not have enough water can purchase water to reduce their losses. In this work, we explore how auction-based negotiation in a multi-agent setting can be used to maximise water sharing within a community during periods of water scarcity. We evaluate various auction mechanisms that can be used to distribute excess water. In addition, we investigate the effect of various different agents' behaviours on water distribution and community profit. [ABSTRACT FROM AUTHOR]

In Canterbury, New Zealand, there has been widespread conversion of dryland sheep grazing to more intensive irrigated dairying. We determined the effects of these land uses on soil carbon on a centre-pivot sprinkler-irrigated dairy farm site, a dryland sheep site, and a non-grazed control site. The dairy site had significantly greater carbon density and carbon storage at 10–20 cm and 0–30 cm depths than the sheep farm site. The dairy farm site had significantly greater carbon stock (equivalent soil mass method) than the sheep farm site at 10–20 cm depth. The dairy farm site intensification did not adversely affect soil carbon, including carbon stock by the equivalent soil mass method. The effects of dairy effluent application on soil water repellency and water movement were investigated. The dairy site had significantly greater subcritical repellency index than the sheep site and a dairy effluent site. Further research is required across more farms and soils to confirm these results in these land uses and under other management and climate conditions. [ABSTRACT FROM AUTHOR]

There is mounting concern in New Zealand and worldwide about the impacts of current and projected land-use activities on freshwater quality. In 2011, the New Zealand government effected the National Policy Statement for Freshwater Management, requiring all regional councils to establish freshwater nutrient loads and water allocation measures in their land and water regional plans. These ‘limits’ must achieve locally defined social, economic and cultural outcomes while, as a minimum, halting any decline in water quality. The authors have participated in the Canterbury region’s strategic land and water planning activities. This has involved strategically assessing the social impacts of ‘limit options’ on aspects of catchment life and then integrating them into official reports and community deliberations, which ultimately inform the development of rules for catchment land use. This paper highlights practice issues which were confronted in the process and how they were managed. [ABSTRACT FROM PUBLISHER]

The annual regeneration from seeds of subterranean clover plants after initial sowing depends on the hardseededness (HSmax, %), its breakdown rate (HSbreak, %/ °C) and the germinability of the seeds over time. Hardseededness is a physical mechanism of dormancy that prevents germination of seeds and is ecologically important for the persistence of subterranean clover in a range of environments. The effects of genotype (G) and sowing time (environment, E) on hardseedednes and germination were investigated for 'Antas', 'Denmark', 'Leura', 'Monti', 'Narrikup' and 'Woogenellup' harvested from six different sowing dates (June 2015–March 2016) in a field experiment in Canterbury, New Zealand. 'Antas' had a lower HSmax (53%) than 'Monti' (86%). HSbreak was affected by the G x E interaction with a doubling of HSbreak from 0.011%/°C for the June sowing date to ∼0.02%/°Cd for the February sowing date for 'Denmark', 'Leura', 'Monti' and 'Narrikup'. There was less sensitivity of 'Antas' and 'Wogenellup' to sowing time. There was an increase in the percentage of abnormal seedlings as the sowing date advanced from winter to late-summer. The developed parameters enabled estimation of seedling emergence and indicate cultivars which have a competitive advantage of an early seedling regeneration in temperate regions. [ABSTRACT FROM AUTHOR]

Herbicide-resistant weeds are a growing challenge in agricultural systems worldwide, leading to additional management costs and yield losses. Best practice management guidelines have been promoted for decades, yet incidences of resistance continue to increase. In New Zealand, herbicide resistance might be more widespread than commonly assumed. To respond to the emerging challenge, this article draws on qualitative social research with arable farmers and agricultural stakeholders in the Canterbury region to describe drivers underlying herbicide use on three levels: individuals' psycho-social context, farm system characteristics, and the socioeconomic system. While findings show concerns for maintaining practical and profitable farm operations, we argue that farmers' herbicide use is influenced by diverse biophysical, technological, and sociocultural factors, with some hindering recommended best practice. These findings demonstrate that integrated systems-based approaches are needed to holistically understand herbicide use as a critical step in collaborative efforts to establish feasible practice guidelines and management strategies. [ABSTRACT FROM AUTHOR]

Irrigation decision-making is complex. It requires balancing multiple risks . We examined if incorporation of weather forecasts into irrigation decision-making improved environmental and economic outcomes on dairy farms in Canterbury, New Zealand. We focused on understanding how farmers can manage irrigation decision-making with uncertain weather forecasts, and the associated impacts on drainage, pasture growth and economics. Previous work had demonstrated that weather conditions were not used in irrigation decision-making as much as desirable and that weather forecast uncertainty was not explicitly considered. We incorporated weather forecasts as a perfect forecast and the best available forecast. We used probability percentiles to incorporate forecast uncertainty into decision-making. The research hypothesis was that through utilising risk profiles of factors that influence environmental and economic outcomes of irrigation decisions, farmers could improve decison-making when faced with uncertain future weather states. When weather forecasts were integrated into irrigation decision-making, there were environmental and economic benefits relative to a simple deficit-based irrigation decision rule. Based on a case study, we predicted 5% additional profit (approximately, $200 per hectare) may be possible when the best available forecasts was used relative to a simple deficit-based decision rule, and a further 1% profit if forecast uncertainty was considered. [ABSTRACT FROM AUTHOR]

Phosphorus (P) release from sediments accumulating since catchment deforestation, has been linked to algal blooms which have occurred in Lake Wairewa (Canterbury, NZ) for over a century. However, the mechanisms controlling this internal P loading are poorly understood. To address this issue, we investigated sediment P fractions, P release, dissolved oxygen (DO) and pH at the sediment–water interface, and undertook targeted water sampling. Sediment depth profiles of P fractions indicated surface enrichment (1600 mg P kg−1), which was due to an upward flux of P from legacy sediments deposited over at least the last 100 years. Phosphorus release under reducing conditions (0.75–64 mg P m−2 d−1) and pH >9.00 (3.27–11.07 mg P m−2 d−1) indicated the potential for internal loading. Low DO events (<2 mg L−1) in bottom waters were short-lived, and spatially discrete, although longer events (13 days) were observed. pH was variable (6.20–10.80), and prolonged periods of pH >9 (5–6 days) were recorded. Macrophyte beds were key drivers of low DO, elevated pH, and sedimentary P release. The results challenge the paradigm of well mixed shallow lakes and contribute to the knowledge required to understand shallow lake systems impacted by land-use change. [ABSTRACT FROM AUTHOR]

Nitrogen (N) leaching losses from grazed pasture systems pose a risk to the environment with mitigation strategies urgently required to achieve regulatory limits. There has been increased interest in alternative forages to manipulate excretion of urinary-N of livestock. This review summarises research on key forage attributes which affect the pattern of urine-N excretion. The literature showed an opportunity to alter both N concentration and moisture concentration of forages to reduce urine patch N loading. Complementary mitigations of extending the grazing rotation and reducing fertiliser were tested in simulations in addition to a diuresis effect on nitrate leaching in pastoral dairy systems. Findings suggested that forage species alone could not substantially reduce (by more than 20%) nitrate leaching. Combining all forage, management and systems-based solutions led to the greatest reductions in nitrate leaching, 59 and 31% for Waikato and Canterbury. Nonetheless, reductions in N loss came at the expense of pasture productivity which will likely affect profitability and farmer adoption of this suite of solutions in the absence of other drivers. The role of plant secondary metabolites in microbial dynamics has implications on N recycling in soil and rumen environments and this was identified as an area for further research. [ABSTRACT FROM AUTHOR]

Nitrate leaching from soil is a major problem in New Zealand pastoral systems, requiring development of practical methods to manage accumulation of nitrates. Nine feed trials were carried out in the Waikato (n = 3) and in Canterbury (n = 6) between 2013 and 2016; from which 424 samples were selected for forage quality testing. Only tick beans and forage rape met the lactating feed criteria for adequate crude protein (CP; > 16% DM) and soluble sugars and starch (SSS; > 25% DM). When an 'environmental' criterion was added to a feed value for lactating cows this reduced the options to fodder beet only. However, the CP measurements for fodder beet were suboptimal for milk production, requiring the fodder beet to be mixed with high protein feeds such as pasture or pasture silage. The lower protein requirements for non-lactating cows, including an additive environmental criterion enabled a wider range of feeds to be considered e.g. kale, sunflowers and swedes in Canterbury (12 entries) and fodder beet and rape in the Waikato (21 entries). Addition or restriction of nitrogen fertiliser was the only agronomic management intervention that consistently altered animal feed quality and potentially changed N excretion. Crop choice was likely to have the greatest impact at the farm level. By limiting feed quality assessment to CP, SSS and their ratio (SSS:CP) we were able to define a selection/feed monitoring method to minimise N content of feed, maximise SSS feed value and limit excess N intake to reduce the nitrate leaching risk. [ABSTRACT FROM AUTHOR]

A 3-year study was carried out in Canterbury, New Zealand, to determine the effect of a nitrification inhibitor dicyandiamide (DCD) on N2O emissions, nitrate () leaching and pasture yield. In all 3 years, DCD was highly effective in reducing N2O emissions from urine-nitrogen (N) applied in autumn (April and May), decreasing the N2O emission factor by 41%–82%. In addition, DCD consistently reduced-N leaching losses by 48%–69% from the animal urine applied in April. Pasture yield responses to DCD application varied from 0%–17%, probably due to other growth limiting factors and/or the methodology used in the pasture yield measurement. The reductions inleaching are of particular value at this point in time due to the increasingly strict regional council regulations that are being imposed on farmers to reduce N leaching losses. [ABSTRACT FROM AUTHOR]