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Disasters are often followed by a large-scale stimulus supporting the economy through the built environment, which can last years. During this time, official economic indicators tend to suggest the economy is doing well, but as activity winds down, the sentiment can quickly change. In response to the damaging 2011 earthquakes in Canterbury, New Zealand, the regional economy outpaced national economic growth rates for several years during the rebuild. The repair work on the built environment created years of elevated building activity. However, after the peak of the rebuilding activity, as economic and employment growth retracts below national growth, we are left with the question of how the underlying economy performs during large scale stimulus activity in the built environment. This paper assesses the performance of the underlying economy by quantifying the usual, demand-driven level of building activity at this time. Applying an Input–Output approach and excluding the economic benefit gained from the investment stimulus reveals the performance of the underlying economy. The results reveal a strong growing underlying economy, and while convergence was expected as the stimulus slowed down, the results found that growth had already crossed over for some time. The results reveal that the investment stimulus provides an initial 1.5% to 2% growth buffer from the underlying economy before the growth rates cross over. This supports short-term economic recovery and enables the underlying economy to transition away from a significant rebuild stimulus. Once the growth crosses over, five years after the disaster, economic growth in the underlying economy remains buoyant even if official regional economic data suggest otherwise. [ABSTRACT FROM AUTHOR]

The severity of surface manifestation of liquefaction is commonly used as a proxy for liquefaction damage potential. As a result, manifestation severity index (MSI) models are more commonly being used in conjunction with simplified stress-based triggering models to predict liquefaction damage potential. This paper assesses the limitations of three existing MSI models and a fourth MSI model that is developed herein. The different models have differing attributes that account for factors influencing the severity of surficial liquefaction manifestations, with the newly proposed model accounting more factors than the others. The efficacies of these MSI models are evaluated using well-documented liquefaction case histories from Canterbury, New Zealand, with the deposits primarily comprising clean to nonplastic silty sands. It is found that the MSI models that explicitly account for the contractive/dilative tendencies of soil did not perform as well as the models that do not account for this tendency, opposite of what would be expected based on the mechanics of liquefaction manifestation. The likely reason for this is the double-counting of the dilative tendencies of medium-dense to dense soils by these MSI models because the liquefaction triggering model, to some extent, inherently accounts for such effects. This implies that development of mechanistically more rigorous MSI models that are used in conjunction with simplified triggering models will not necessarily result in improved liquefaction damage potential predictions and may result in less accurate predictions. This provides the impetus for the development of a new framework that clearly and distinctly separates triggering and manifestation. [ABSTRACT FROM AUTHOR]

This paper examines farmers' ways of knowing water quality and their encounters with the science used in policy to address the cumulative effects of agriculture. Drawing on constructivist theories of knowledge and discussions with farmers in two locations of New Zealand's South Island region of Canterbury, the research identifies a significant divergence between farmers' conception of the water quality problem compared to the issue's policy framing. In theory, and increasingly in practice, ways of knowing are assumed merely out-of-sync and their integration or coproduction possible and necessary. This paper poses the question: what if the ways of knowing of farmers and science have become incompatible? The presented research indicates incompatibility that derives from epistemic practices that mobilise different ontologies at different scales. It is shown how the predictive practices of science present what appear to be insurmountable obstacles to integration or coproduction. It is argued that collaborative governance needs to find ways to work with divergent ways of knowing -- not for the purpose of integration or coproduction but co-existence. [ABSTRACT FROM AUTHOR]

Resistance of sawtoothed grain beetle (Oryzaephilus surinamensis) to organophosphate insecticides is documented internationally. There are anecdotal reports of reduced efficacy in New Zealand but to date no empirical assessments have been made. Two-laboratory-based test methods using either a dust (ActellicR Dust) or liquid (ActellicR 50EC) formulations of pirimiphos-methyl, were compared to determine the response of five Canterbury sawtoothed grain beetle populations. A mini-silo method employed grain treated with the recommended application rate (200 g a.i./tonne seed) of pirimiphos-methyl dust. A Petri-dish method treated internal surfaces of 50-mm diameter Petri dishes with liquid pirimiphos-methyl at concentrations from 0-0.1 g a.i./L to determine an estimated LC50 (lethal concentration for 50% mortality) for each population. The rank order of mortality (highest to lowest) in the mini-silo test was similar to the Petri-dish LC50 rankings for the five populations tested. The results illustrate variation in responses to pirimiphosmethyl concentrations by sawtoothed grain beetle populations, indicating both methods are potential options for future resistance testing and will aid the development of management strategies for control of stored insect pests. [ABSTRACT FROM AUTHOR]

Context The American College of Radiology Thyroid Image Reporting and Data System (ACR TI-RADS) was developed to predict malignancy risk in thyroid nodules using ultrasound features. TI-RADS was derived from a database of patients already selected for fine-needle aspiration (FNA), raising uncertainty about applicability to unselected patients. Objective We aimed to assess the effect of ACR TI-RADS reporting in unselected patients presenting for thyroid ultrasound in a real-world setting. Methods Records for all patients presenting for thyroid ultrasonography in Canterbury, New Zealand, were reviewed across two 18-month periods, prior to and after implementation of TI-RADS reporting. Patient outcomes were compared between the 2 periods. Malignancy rates were calculated for nodules 10 mm or larger with a definitive FNA or histology result. Results A total of 1210 nodules were identified in 582 patients prior to implementation of TI-RADS; 1253 nodules were identified in 625 patients after implementation of TI-RADS. TI-RADS category was associated with malignancy rate (0% in TR1 and TR2, 3% in TR3, 5% in TR4, 12% in TR5; P =.02); however, 63% of nodules were graded TR3 or TR4, for which malignancy rate did not meaningfully differ from baseline risk. After implementation of TI-RADS there was a small reduction in the proportion of patients proceeding to FNA (49% vs 60%; P <.01) or surgery (14% vs 18%; P <.05), with no difference in cancer diagnoses (3% vs 4%, not significant). Conclusion TI-RADS category is associated with malignancy rate and may alter clinical decision-making in a minority of patients; however, it is nondiscriminatory in the majority of nodules. In this study of unselected patients, nodules classified as TR5 and thus considered "highly suspicious" for cancer had only a modest risk of malignancy. [ABSTRACT FROM AUTHOR]

Synthetic herbicides have revolutionised agricultural weed control. Herbicide resistance (HR) is a natural process through which weeds evolve to be no longer susceptible to a herbicide. Repeated use of similar herbicides can lead to the proliferation of resistant weed populations, with detrimental on-farm effects. To date, 267 weed species worldwide are resistant to at least one herbicide. Yet, achieving universal uptake of best practice principles to manage HR remains difficult. Historically not a high priority for New Zealand cropping farmers, resistance may be more prevalent than commonly assumed. This article contributes to emerging national management strategies and the international scholarship on the human dimensions of HR. Regarding resistance as a socio-biological challenge, we draw on qualitative social research with agricultural stakeholders in New Zealand's main cropping region to outline important psychosocial preconditions for effective resistance management. Our findings show that these preconditions include: influencing awareness and attitudes, knowledge and skills; approaching HR as a shared responsibility; and supporting long-term and holistic thinking. We conclude that these preconditions form the social foundations for agricultural stakeholders' capacity to enact best practice principles to continuously re-solve HR. This novel framing allows analytical differentiation between the capacity and ability to act, with practical recommendations and future research needing to address both components of effective HR management. [ABSTRACT FROM AUTHOR]

The severity of surficial liquefaction manifestation was significantly over-predicted for a large subset of case histories from relatively recent earthquakes that impacted the Canterbury region of New Zealand. Such over-predicts generally occurred for profiles having predominantly high fines-content (FC), high-plasticity soil strata. Herein, the liquefaction case histories from the Canterbury earthquakes are used to investigate the performances of three different manifestation severity index (MSI) models. The prevalence of high FC, high-plasticity strata in a profile is quantified through the soil behavior type index averaged over the upper 10 m of a profile (Ic10). It is shown that for each MSI model (1) the threshold MSI value distinguishing cases with and without manifestation increases as Ic10 increases and (2) the ability of the MSI to segregate cases with and without manifestation decreases with increasing Ic10. Additionally, probabilistic models are proposed for evaluating the severity of surficial liquefaction manifestation as a function of MSI and Ic10. The approaches presented in this study allow better interpretations of predictions made by existing MSI models, although their efficacy decreases at sites with high Ic10. An improved MSI model is ultimately needed that better accounts for the effects of high-FC, high-plasticity soils more directly. [ABSTRACT FROM AUTHOR]

The devastating earthquake sequence in Christchurch and Canterbury has resulted in the removal of over 1200 buildings in the former Christchurch CBD. Add to this the damage to over 100,000 homes and the impact on the lives of the 436,000 residents of Greater Christchurch. The Canterbury Earthquakes have provided an unprecedented opportunity to rethink, revitalise and renew Central Christchurch. Aided by an investment of greater than NZ$40bn, sourced via insurance, central and local government contributions and topped up by commercial and private investment, with construction at its peak, we are experiencing a spend rate exceeding NZ$100 M per week. Out of the rubble is emerging a well-formed and vibrant city centre that produces economic and social benefits by bringing together people for business, cultural or social activities. The “new Christchurch” is being built upon the principles of resilience, sustainability and connectedness, whilst also reflecting our history through the retention and enhancement of key heritage buildings and infrastructure assets framed by green spaces and accessible pathways. This paper introduces some of the initiatives put in place as building blocks to drive the recovery of the new City Core, and indeed greater Christchurch and Canterbury Area. These initiatives range from improved building structural standards and codes, to ‘Green’ building rating tools, to Energy Design Advice Grants and “Smart City” development principles. The new Christchurch can be (and is being) defined by its accessible, connected, resilient and high performing building stock. Only time will be the ultimate judge, however after just over 5 years, the city is going from strength to strength and Christchurch continues to provide a significant contribution to the national economy. [ABSTRACT FROM AUTHOR]

Groundwater recharge rates and volumes underpin water resource allocation decisions. Drainage lysimeters ('lysimeters') provide a direct, continuous measurement of drainage below the root zone. However, owing to their pointscale nature and limited depth, such measurements are seldom used to estimate potential groundwater recharge and subsequent allocation decisions. A combination of Artificial Neural Network (ANN) and uncertainty estimation techniques were applied to upscale lysimeter-based drainage measurements to the regional scale to estimate unconfined aquifer groundwater recharge. We trained ANN models using drainage data from three lysimeter sites across the Canterbury plains of New Zealand. The best predictive model, in terms of accuracy and parsimony, provided coefficient of determination (R2) values of 0.65, 0.74 and 0.86 at the three lysimeter sites, with a relative model uncertainty of 6%. The model was then implemented within a geographic information system (GIS) to predict the spatial variability of land surface recharge to support groundwater allocation at the regional scale. The GISintegrated ANN model provides a computationally inexpensive method of upscaling pointscale drainage data into regionalscale recharge estimates. In a next step these estimates can be refined by implementing additional data, such as spatially distributed soil moisture measurements, into the ANN. [ABSTRACT FROM AUTHOR]

The land application of biosolids can result in the unacceptable accumulation of Trace Elements (TEs) in agricultural soil and potentially introduce xenobiotics and pathogens into the food chain. Phytoremediation of biosolids aims to minimize this risk, while producing valuable biomass. Willows, well known to accumulate zinc (Zn), are used extensively in farming systems for soil conservation, shelter and as feed supplements with demonstrable health benefits. Potentially, biosolids phytoremediation could occur on marginal lands adjacent to farmlands where willows are grown for supplementary fodder. We aimed to determine the uptake and distribution of Zn and other TEs in willows grown on soils amended with biosolids and biosolids blended with biochar, with a view to their use as stock fodder. In the Canterbury Region, New Zealand, we grew Salix 'tangaio' (S. matsudana X S. alba) in a greenhouse trial and field study. The biomass production of the willows was unaffected by biosolids and increased by the biosolids+biochar mixture. The addition of 4% biosolids (w/w) to the soil resulted in a foliar Zn concentration of 600–1000 mg kg−1, some 25 times higher than the average New Zealand pasture. Zinc concentrations were highest in the bottom leaves and increased throughout the season. Biosolids addition doubled the copper (Cu) concentration to 10 mg kg−1. Adding biochar to the system reduced the plant uptake of Cu and to a lesser extent Zn, while cadmium (Cd) uptake was unaffected. For Cd, Cu, and Zn, plant uptake was a function of the Ca(NO3)2-extractable concentration, both in greenhouse experiments and the field trial. Future work should determine the changes in plant TE uptake over several growing seasons. [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 emergence of clinically significant antimicrobial resistance (AMR) in bacteria is frequently attributed to the use of antimicrobials in humans and livestock and is often found concurrently with human and animal pathogens. However, the incidence and natural drivers of antimicrobial resistance and pathogenic virulence in the environment, including waterways and ground water, are poorly understood. Freshwater monitoring for microbial pollution relies on culturing bacterial species indicative of faecal pollution, but detection of genes linked to antimicrobial resistance and/or those linked to virulence is a potentially superior alternative. We collected water and sediment samples in the autumn and spring from three rivers in Canterbury, New Zealand; sites were above and below reaches draining intensive dairy farming. Samples were tested for loci associated with the AMR-related group 1 CTX-M enzyme production (blaCTX-M) and Shiga toxin producing Escherichia coli (STEC). The blaCTX-M locus was only detected during spring and was more prevalent downstream of intensive dairy farms. Loci associated with STEC were detected in both the autumn and spring, again predominantly downstream of intensive dairying. This cross-sectional study suggests that targeted testing of environmental DNA is a useful tool for monitoring waterways. Further studies are now needed to extend our observations across seasons and to examine the relationship between the presence of these genetic elements and the incidence of disease in humans. [ABSTRACT FROM AUTHOR]

To estimate the prevalence of herbicide-resistant weeds, 87 wheat and barley farms were randomly surveyed in the Canterbury region of New Zealand. Over 600 weed seed samples from up to 10 mother plants per taxon depending on abundance, were collected immediately prior to harvest (two fields per farm). Some samples provided by agronomists were tested on an ad-hoc basis. Over 40,000 seedlings were grown to the 2–4 leaf stage in glasshouse conditions and sprayed with high priority herbicides for grasses from the three modes-of-action acetyl-CoA carboxylase (ACCase)-inhibitors haloxyfop, fenoxaprop, clodinafop, pinoxaden, clethodim, acetolactate synthase (ALS)-inhibitors iodosulfuron, pyroxsulam, nicosulfuron, and the 5-enolpyruvyl shikimate 3-phosphate synthase (EPSPS)-inhibitor glyphosate. The highest manufacturer recommended label rates were applied for the products registered for use in New Zealand, often higher than the discriminatory rates used in studies elsewhere. Published studies of resistance were rare in New Zealand but we found weeds survived herbicide applications on 42 of the 87 (48%) randomly surveyed farms, while susceptible reference populations died. Resistance was found for ALS-inhibitors on 35 farms (40%) and to ACCase-inhibitors on 20 (23%) farms. The number of farms with resistant weeds (denominator is 87 farms) are reported for ACCase-inhibitors, ALS-inhibitors, and glyphosate respectively as: Avena fatua (9%, 1%, 0% of farms), Bromus catharticus (0%, 2%, 0%), Lolium spp. (17%, 28%, 0%), Phalaris minor (1%, 6%, 0%), and Vulpia bromoides (0%, not tested, 0%). Not all farms had the weeds present, five had no obvious weeds prior to harvest. This survey revealed New Zealand's first documented cases of resistance in P. minor (fenoxaprop, clodinafop, iodosulfuron) and B. catharticus (pyroxsulam). Twelve of the 87 randomly sampled farms (14%) had ALS-inhibitor chlorsulfuron-resistant sow thistles, mostly Sonchus asper but also S. oleraceus. Resistance was confirmed in industry-supplied samples of the grasses Digitaria sanguinalis (nicosulfuron, two maize farms), P. minor (iodosulfuron, one farm), and Lolium spp. (cases included glyphosate, haloxyfop, pinoxaden, iodosulfuron, and pyroxsulam, 9 farms). Industry also supplied Stellaria media samples that were resistant to chlorsulfuron and flumetsulam (ALS-inhibitors) sourced from clover and ryegrass fields from the North and South Island. [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]

The multifractal detrended fluctuation algorithm is applied to a series of distances and elapsed times between consecutive earthquakes recorded along the years 2000–2018 in the Canterbury region (New Zealand). The time evolution of several multifractal parameters (Hurst exponent, Hölder central and maximum exponents, spectral amplitude, asymmetry, and complexity index) is analyzed. Peaks of multifractal parameters, with statistical significance exceeding 95%, are associated with three earthquakes of notable magnitude (equaling or exceeding Mw = 5.7). Additionally, some other peaks are also associated with the swarm of earthquakes of moderate magnitude. Possible shortcomings created by this assignment to mainshocks or swarms can be removed by comparing the results corresponding to elapsed times and interevent distances between consecutive events. Additionally, the Buishand test, which is used to verify the statistical significance of the detected peaks, also discriminates between mainshocks of notable seismic magnitude and swarms of earthquakes with moderate magnitude. The obtained results, based on the multifractal structure of the seismic activity, could also represent some advances in predicting, with sufficient time, forthcoming mainshocks of high magnitude and mitigate their destructive effects. [ABSTRACT FROM AUTHOR]

Although offshore freshened groundwater (OFG) systems have been documented in numerous continental margins worldwide, their geometry, controls and emplacement dynamics remain poorly constrained. Here we integrate controlled-source electromagnetic, seismic reflection and borehole data with hydrological modelling to quantitatively characterise a previously unknown OFG system near Canterbury, New Zealand. The OFG system consists of one main, and two smaller, low salinity groundwater bodies. The main body extends up to 60 km from the coast and a seawater depth of 110 m. We attribute along-shelf variability in salinity to permeability heterogeneity due to permeable conduits and normal faults, and to recharge from rivers during sea level lowstands. A meteoric origin of the OFG and active groundwater migration from onshore are inferred. However, modelling results suggest that the majority of the OFG was emplaced via topographically-driven flow during sea level lowstands in the last 300 ka. Global volumetric estimates of OFG will be significantly revised if active margins, with steep coastal topographies like the Canterbury margin, are considered. The authors here combine a range of geophysical data, numerical modelling and borehole data to present a high resolution map of an offshore freshened groundwater system in the Canterbury Bight, New Zealand. The study shows the extensions of the offshore freshened groundwater system to be controlled by high permeability shelf sediments, buried paleochannels and onshore rivers. [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]

Phoma betae is an economically important pathogen of red beet causing preemergence seedling damping, leaf spot and root rot. However, the pathogenicity of P. betae is unknown in New Zealand despite the economic importance of this pathogen. Twenty-five isolates were collected from a survey of red beet seed farms in Canterbury, New Zealand during 2016/2017 and three of these PB101 (from seeds), PB103 (from roots) and PB106 (from leaves) were used for pathogenicity testing of two red-beet cultivars. Isolate PB106 was further used to investigate its effects on spinach and fodder beet as well as red beet under greenhouse conditions. All three P. betae isolates were pathogenic on both red-beet cultivars tested, causing leaf-spot symptoms. Isolates PB101 and PB106 produced significantly larger leaf-spot lesions (P<0.001) compared with PB103. Phoma betae isolate PB106 was pathogenic to both red-beet cultivars, spinach and fodder beet but fodder beet was less susceptible than the other species tested. Regardless of cultivar, P. betae is an important pathogen of beets and is capable of causing leaf spots. [ABSTRACT FROM AUTHOR]

River flow is one of the key determinants of the quality and value of white water recreational resources. However, water abstraction for activities such as irrigation and hydroelectric power generation may reduce the availability of preferred flows with consequential impacts on recreational river users. We evaluated kayaking and rafting values in the Rangitata River, Canterbury, New Zealand under the current flow regime and for a proposed additional high-flow take of 10 m3/s, on a reach between the Klondyke gauge and the Arundel Bridge. This reach is recognised for its outstanding kayaking and rafting values under the Water Conservation (Rangitata River) Order 2006. Differences in flow characteristics between the scenarios were quantified using simulations derived from a 48-year record of mean daily flow over a November to April paddling season, and hourly flow data for a fresh event. Impacts were evaluated by examining the number of days in preferred flow ranges (boatable days) for different user groups. The proposed 10 m3/s take increases boatable days for beginner and intermediate rafters (with a preferred flow range of 55-250 m³/s) and intermediate kayakers (45-170 m³/s) by 0.5 and 1.6 days (0.5% and 1.6%), respectively, perhaps suggesting a small net benefit for boaters. However, boatable days increase by 5.6 days (163%) in the 95-100 m³/s flow band by the flat-lining of flows, whilst flows > 100 m³/s reduce by 5.1 and 4.0 days (15.7% and 16.6%) for beginner and intermediate rafters, and intermediate kayakers, respectively, revealing significant negative underlying impacts. Thus, there can be drawbacks and limitations in the use of overall boatable days or changes in boatable days as the basis for quantifying abstraction impacts. It is essential that boatable days in the component flow ranges preferred by different user groups are considered and analysed in order to determine the true impact of flow takes. [ABSTRACT FROM AUTHOR]

Ryegrass, both perennial (Lolium perenne) and annual (L. multiflorum), can be weeds in other arable crops such as wheat (Triticum aestivum). They are generally removed using selective herbicides, but herbicide-resistant perennial and annual ryegrasses have been reported anecdotally. Perennial ryegrass seeds that were suspected to be herbicide resistant were sourced from near Methven, Canterbury. They were evaluated for tolerance to five herbicides and were found to be resistant to all of them. In a separate experiment, annual ryegrass seeds that were suspected to be herbicide resistant were also sourced from near Methven, Canterbury. They were evaluated for tolerance to six different herbicides and were found to be resistant to haloxyfop applied at up to four times label rate but susceptible to clethodim. These results have important implications for growers and advisers throughout New Zealand. [ABSTRACT FROM AUTHOR]

Despite their good performance in terms of their design objectives, many modern code-prescriptive buildings built in Christchurch, New Zealand, had to be razed after the 2010–2011 Canterbury earthquakes because repairs were deemed too costly due to widespread sacrificial damage. Clearly, a more effective design paradigm is needed to create more resilient structures. Rocking, posttensioned connections with supplemental energy dissipation can contribute to damage avoidance designs (DAD). However, few have achieved all three key design objectives of damage-resistant rocking, inherent recentering ability, and repeatable, damage-free energy dissipation for all cycles, which together offer a response that is independent of loading history. Results of experimental tests are presented for a near full-scale rocking beam-column subassemblage. A matrix of test results is presented for the system under varying levels of posttensioning, with and without supplemental dampers. Importantly, this parametric study delineates each contribution to response. Practical limitations on posttensioning are identified: a minimum to ensure static structural recentering and a maximum to ensure deformability without threadbar yielding. Good agreement between a mechanistic model and experimental results over all parameters and inputs indicates the model is robust and accurate for design. The overall results indicate that it is possible to create a DAD connection where the nonlinear force-deformation response is loading history independent and repeatable over numerous loading cycles, without damage, creating the opportunity for the design and implementation of highly resilient structures. [ABSTRACT FROM AUTHOR]

The article discusses the effectiveness of the implementation of the Canterbury Water Management Strategy (CWMS) in Canterbury, New Zealand.

This article compares the proximate but not parallel trajectories of Canterbury Regional Council's (ECan) and the Christchurch City Council's changing authority to manage the urban and natural environment from 2010 to 2015. We ask why the trajectories are so far from parallel, and speculate as to why the central government interventions were so different. The apparent mismatch between the justifications for the interventions and the interventions themselves reveals important implications on the national and local levels. Nationally, the mismatch speaks to the current debate over an overhaul of the Resource Management Act. Locally, it informs current discussions in Wellington, Nelson, Gisborne and elsewhere about amalgamating district and regional councils. [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]

This study evaluates energy efficiency of pastoral (PDFs) and barn (BDFs) dairy farming systems in New Zealand through application of data envelopment analysis (DEA) approach. Two models constant return to scale (CCR) and variable return to scale (BCC) of DEA were employed for determining the technical (TE), pure technical (PTE) and scale (SE) efficiencies of New Zealand pastoral and barn dairy systems. Further, benchmarking was also performed to separate efficient and inefficient dairy farms and energy saving potential was identified for both dairy systems based upon their optimal energy consumption. For this study, the energy inputs data were taken from 50 dairy farms (including PDFs and BDFs) across Canterbury, New Zealand. The results indicated that the average technical, pure technical and scale efficiencies of pastoral (PDFs) dairy systems were 0.84, 0.90, 0.93 and for barn (BDFs) systems were 0.78, 0.84, 0.92, respectively, showing that energy efficiency is slightly better in PDFs system than the BDFs. From the total number of dairy farms 40% and 48% were efficient based on the constant return to scale and variable return to scale models, respectively. Further, the energy saving potential for PDFs and BDFs dairy systems through optimal energy consumption were identified as 23% and 35%, respectively. Thus, energy auditing, use of renewable energy and precision agricultural technology were recommended for energy efficiency improvement in both dairy systems. [ABSTRACT FROM AUTHOR]

In pines, the release of seeds from serotinous cones is primarily considered a response to the high temperatures of a fire. However, the naturalization of serotinous pines in regions where fires are rare highlights the need to quantify environmental conditions that determine seed release to allow accurate prediction of dispersal and spread risk. We investigated the conditions that break cone serotiny in Pinus radiata , a widely planted forestry species that has naturalized in temperate regions worldwide. We quantified the cone temperatures at which cones open in this species, while also assessing potential confounding effects of cone moisture and age on these temperature requirements. We compared our laboratory results with cone opening behaviour under typical field conditions during summer in Canterbury, New Zealand. Cones opened at a mean temperature of 45 °C, much higher than maximum ambient air temperatures recorded in New Zealand. We found no influence of cone age or moisture content on opening temperature. Under field conditions, cones opened upon reaching similar temperatures to those determined in the laboratory; however, passive solar heating caused cones to reach temperatures up to 15 °C higher than ambient conditions. This resulted in 50 % of cones opening in field conditions where maximum air temperatures never exceeded 30 °C. Our results highlight the need for complementary laboratory and field experiments for understanding seed release from serotinous cones. Our findings have important implications for weed risk assessments, showing that serotinous pines can release seed in temperate climates without fire. [ABSTRACT FROM AUTHOR]