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Better understanding of the following is needed to inform improved nutrient-management tools and water-take limits in the Pukekohe–Bombay area: • Conceptual groundwater flow; • Connection with surface water; • Nitrate pathways; • Potential risk of nitrate contamination of deeper aquifers; • ‘Future nitrate loads to come’; • Connections within the aquifer system. Refined groundwater ages, together with hydrochemistry, water isotopes and atmospheric gas concentrations, enabled detailed understanding of groundwater flow processes. Groundwaters in the aquifers underlaying the Pleistocene deposits and in the deep basalt aquifers are all old, implying very little active circulation through these deeper systems. Rain onto the Pleistocene deposits therefore drains, mainly during the wet season, through shallow, fast-flow paths, without sufficient storage reservoir to sustain significant stream flow during baseflow in the dry season.Active subsurface drainage through large groundwater reservoirs only occurs through the basalt lava of the Pukekohe and Bombay volcanoes and, to a lesser extent, through the unconsolidated volcanic materials, including tuff and tephra. The active groundwater flow systems in the basalt lava have sufficient storage to maintain significant stream baseflow over the course of years. Three main streams drain the basalt lava of the Pukekohe and Bombay volcanoes ontheir northern perimeters: Whangamaire Stream, Whangapouri Creek and Hingaia Stream. These streams have a combined groundwater storage of approximately 350 Mm3. On the south-western flanks of these volcanoes, the upper reaches of the Mauku and Ngakoroa streams also receive discharge from the basalt lava. They have a combined groundwater storage of approximately 37 Mm3. Three main spring systems drain the basalt lava groundwater systems: Hickey, Hillview and Patumahoe springs. The average groundwater flow rates to these springs are approximately 190, 160, and 65 m/y, respectively. Whangamaire Stream and Whangapouri Creek drain the Pukekohe basalt lava at the northern perimeter of the plateau, where they receive most of their flow. Groundwater age, isotopes and hydrochemistry match those of the water in these streams, including high nitrate concentrations. There is no significant flow gain north of the basalt lava within the Pleistocene deposits, indicating absence or insignificance of deep groundwater flux to these streams. This implies that these areas drain only via shallow flow paths that are depleted during summer baseflow conditions. Hingaia Stream receives water in its upper reaches partially from impermeable greywacke basement rock catchments and partially from the north-eastern perimeter of the basalt lava. The mixing of water from the essentially pristine greywacke catchment with water recharged in areas of high nitrate leaching activities results in medium nitrate concentrations. At the northern perimeter of the volcanic cone, where Hillview Spring discharges into Hingaia Stream, flow more than doubles, as does nitrate concentration. Groundwater ages, isotopes and hydrochemistry match those of the water discharging from Hillview Spring, including high nitrate concentrations. In the upper reaches of Ngakoroa Stream, isotopes and nitrate indicate flow contribution from the south-western, low-altitude flanks of the Bombay basalt lava. North of the basalt, the stream does not gain any significant flow. However, nitrate concentration decreases significantly, probably due to in-stream processes. Mauku Stream gains flow in its upper reaches from the Pukekohe basalt lava along its south-western perimeter. Groundwater ages, isotopes and hydrochemistry match those of the water in the upper reaches of the stream. From the north-western flanks of the Pukekohe basalt lava, the stream receives water from a groundwater system recharged at lower altitudes and likely to be anoxic. Stream flow more than doubles, while nitrate concentrations become diluted.Oira Creek, having very low flow, discharges locally recharged, relatively old, groundwater with low nitrate concentrations. Similarly, Waitangi Stream discharges locally recharged groundwater with low nitrate concentrations. Both streams are likely to drain anoxic groundwater systems.The most active groundwater drainage flow with the youngest water feeding the springs occurs near the surface of the water tables. Slightly deeper groundwater is older than expected for the upstream position in the active flow path towards the springs. Recharge to the deeper groundwater system is estimated to be 280 mm/y. As indicated by calculated recharge temperatures, recharge to the deeper groundwater system appears to be preferential flow through fractures, allowing fast flow to beneath the water table. This contrasts with the groundwater providing the spring discharges, which is recharged through matrix flow through the bulk material of the unsaturated zone. Fracture flow in the shallow basalt lava appears to be unstable. In all four basalt lava wells in the Pukekohe and upper Waikato area with long-term monitoring data, hydrochemistry parameters (indicative of land use and geologic sources) have changed drastically over recent decades. These changes were permanent, usually from older to younger water, with raising water tables. This indicates changing capture zones for these wells, with each well changing at a different time. Weathered basalts form rich horticultural soils. Since the 1950s, high-intensity market gardening, associated with high nitrate leaching, has resulted in high nitrate loads into the transmissive basalt lava of the Pukekohe and Bombay volcanoes. These basalt lavas discharge oxic groundwater into streams, indicating absence of organic matter and inorganic electron donors in the aquifer, which would be required for facilitation of microbial reactions, including denitrification. Without denitrification occurring, the nitrate load is expected to discharge from this basalt lava without any nitrate attenuation, with a lag time equal to the travel time (age) of the water through the aquifer. On average, it takes 18 years for the nitrate load to travel through the Pukekohe basalt lava and 36 years to travel through the Bombay basalt lava. Assuming approximately constant nitrate load for circa 65 years since the onset of industrial agriculture in around 1955, these groundwater discharges from the basalt have essentially adjusted to the high land-use nitrate loads in the recharge areas. However, nitrate concentrations in the deeper groundwater are still increasing and adjusting to the high nitrate loads in the recharge areas. Due to the relatively long lag times noted above, reducing land-use nitrate loads will take decades to manifest in the baseflow spring discharges of the basalt in the Pukekohe–Bombay area. In contrast to the oxic water discharging from the basalt lava, significant amounts of water (approximately 60 L/s) discharge from the north-western flanks of the Pukekohe basalt lava that appear to be anoxic and low in nitrate, despite discharging from areas with land use associated with high nitrate leaching. There is potential for significant nitrate attenuation in this groundwater system. Denitrification may also be possible in the shallow drainage system of the Pleistocene deposits, near the redox zone (auth)

Atopic dermatitis (AD) is a chronic skin condition affecting an increasing number of children and adults whose quality of life is impacted by chronic itch and pain. It is characterized by an altered epidermal barrier, skin inflammation, and skin microbiome dysbiosis particularly over-colonization of Staphylococcus aureus. The efficacy and tolerance of a cream containing a S. aureus-targeting technology (endolysin) was assessed in an open-label, two-week study in children and adults with mild-to-moderate atopic dermatitis. A total of 43 patients ranging from 7 months to 57 years old were included and all patients finished the study without any tolerance problem. Disease severity, measured with SCORAD, quickly reduced by 43% in 7 days and by 68 % in 14 days. The benefit was perceived by the whole panel with a marked improvement in overall QoL. This study shows the efficacy of a highly specific S. aureus-targeted technology in alleviating symptoms and improving QoL in children and adults with atopic dermatitis. It could also be beneficial in reducing and preventing flares in subjects with S. aureus load due to its good tolerance and specific action. J Drugs Dermatol. 2021;20(12):1323-1328. doi:10.36849/JDD.6363.

In 2016, the National Groundwater Monitoring Programme (NGMP) sampling kit was modified by adding a 100 mL sulfuric-acidified sampling bottle for the analysis of ammonia-nitrogen (NH3-N). This change was prompted by a review applying the most recent version of Standard Methods (Rice et al. 2012), which is the basis for the sampling protocol adopted by the programme since 2006. Acidification was recommended to inhibit bacterial activity and prevent salt formation with organic bases. This report aims to inform on (i) the impact of this operational change on measured NH3-N concentrations at NGMP sites and (ii) the implication of this change on the long-term NGMP dataset. NGMP samples, including the new bottle, were collected by regional council staff as part of quarterly monitoring. Collected samples were then analysed at the New Zealand Geothermal Analytical laboratory for NH3-N, one of the monitored parameters using acid-preserved bottles, and for other parameters, including major ions and trace metals. Duplicate analysis of NH3-N (flow-injection analysis APHA 4500-NH3-H method) was performed on a subset of the unpreserved bottles for cost-effectiveness. The subset was selected to encompass a range of concentrations (

Microbial communities in groundwater carry out biochemical processes that are essential ecosystem functions, such as nutrient cycling and removal of contaminants. These processes play an important role in the quality of groundwater used for drinking and irrigation as well as interconnected surface water. The effects of climate change on these communities, e.g. from increasing salt levels from rising sea levels, or from global temperature increases, are unknown. This study used a combination of culture-dependent (growth curves, isolation of bacteria) and culture-independent (marker gene sequencing, functional gene quantification) methods to identify the potential effects of saltwater intrusion on groundwater microbes and their functions. Groundwater samples were collected from sites in two regions, Waikato and Canterbury, and exposed to a range of concentrations of chloride. Each groundwater sample responded differently to chloride, depending on the microbial community present within that sample. Some groundwater microbial communities were negatively impacted by increasing chloride concentrations, including declines in bacteria responsible for nitrate and ammonia removal. These ecosystems should be prioritised for future protection from sea level rise or increased pumping of groundwater for agriculture. Other samples were stimulated in the presence of chloride, often caused by an increase in abundance of salt-tolerant heterotrophic bacteria using sugars, peptides, or organic acids for energy. Identification of keystone species affected by saltwater in these ecosystems will enable management decisions to be made about future abstraction limits or if defences against sea level rise are needed. (The authors)

This study aims to holistically describe the flow sources, pathways and lag times of water through the rivers and aquifers of the West Coast catchments. This information is required to ground truth and improve groundwater flow models and management tools. Such improvements will help to prevent degradation of rivers and aquifers from land-use activities that impact on cultural, recreational and economical values, as well as on drinking water supplies and quality. This study is mainly funded through the MBIE Endeavour programme ‘Te Whakaheke o Te Wai’ and complemented by the MBIE Envirolink fund (C05X2005). Groundwater chemistry and age tracer data were assembled from a range of sources: (i) GNS’s national datasets (National Groundwater Monitoring Programme, National Tracer Survey), (ii) regional datasets (State Of the Environment monitoring and specific site investigations), (iii) existing data from the Water Dating laboratory and (iv) water samples collected in March 2020 as part of this study. The aggregated dataset consists of 100 sites (including 97 bores, two springs and one river) and spans the period November 1998 to March 2020. The environmental tracer data (age, isotopes, temperature, gas concentration and chemistry) was combined and interpreted using graphical analysis (e.g. Piper diagram) spatial analysis and multivariate statistics. These analyses inform characterisation of groundwater flow and hydrochemical processes in the West Coast aquifers. Short (less than 10 years) residence times are typical for groundwater resources in the region. Three geographically distinct hydrochemical signatures are consistent with topography and geological distinct areas: pristine, alpine foothills (cluster A); impacted coastal or fluvial (clusters B1 and B2) areas; and a dilute valley with indication of land-use impact (clusters C1, C2 and C3). West Coast rivers and streams are hydraulically well connected to adjacent Holocene gravel aquifers. These aquifers are mostly oxic in nature. There is does not appear to be a relationship between well depth and groundwater age, indicating absence of confined or disconnected groundwater condition throughout large parts of the region’s aquifers. In the Grey Valley, groundwaters have tracer signatures indicative of recharge from local rain and rivers. This area has the largest groundwater demand and abstraction for the region (Mourot and White 2020). Time series groundwater age data for the valley was not sensitive enough to identify impact of abstraction on groundwater circulation from increased abstraction between 2012 and 2017 (WCRC 2014). It is expected that significant change in water allocation may be rapidly reflected in future water age monitoring data due to the short residence time of water in this system (auth)

Wer Kulturvermittlung hört, denkt hauptsächlich an Führungen und Workshops in Museen. Wenige von uns verbinden die Kunstvermittlung mit der Ausstellungsinszenierung. Diese ist jedoch die aussagekräftigste Kulturvermittlerin der Originalobjekte. Sie bietet den Objekten einen visuellen Kontext, in dem sie wahrgenommen und interpretiert werden. Sie ist auch das Medium, durch die Kurator*innen, die an die Besucher*innen gerichtete Botschaft senden. Tendenziell wird die Inszenierung als Auslöser von Emotionen genutzt oder die Ausstellungsobjekte dienen als einseitige Illustration eines “Storytellings”. In beiden Fällen rücken jedoch die Materialität und die vielfältigen Bedeutungen eines authentischen Objekts in den Hintergrund. In dieser Masterarbeit wird recherchiert, wie die Inszenierung einen Rahmen bilden kann, in dem Ausstellungsobjekte uns ihre eigene Geschichte erzählen, und somit wieder im Zentrum zu stehen. Wie kann die Mehrdeutigkeit der Objekte bewahrt werden, ohne das Verständnis der Botschaft zu verringern? Kann die Inszenierung, Denotation und Konnotation Prozesse eines Objekts unterstützen, wenn ja, wie? Ist die Materialität der Ausstellungsobjekte für die Deutung des Objekts relevant, oder nur ihre semiotische Seite wird in den Vordergrund gestellt? Ausgehend von der Theorie der Semiotik ist eine systematische Methode entworfen worden. Diese ist für die Untersuchung der Ausstellungspräsentation eines bestimmtes Objekttypus, die byzantinische Reliquienkreuze in Bronze, eingesetzt worden. Diese Arbeit unterliegt dem Versuch zu begreifen mit welchen Mitteln die Inszenierung unabhängig von Ausstellungstexten auch Fachkenntnisse transportieren kann.

Digital datasets of New Zealand hydrogeological systems and their boundaries have been developed using a nationally-consistent and transparent methodology. Here, we define hydrogeological systems as geographical areas with broadly-consistent hydrogeological properties, and similar resource pressures and management issues. These systems are represented in two Geographical Information System (GIS) datasets at the 1:250,000 scale, i.e., hydrogeological system polygons and system boundary polylines. The hydrogeological system polygons (1896 in total) include attributes corresponding to mapping levels, i.e.: unique names; unique identification numbers; system class; coastal information; aquifer overview; geology and age group; and description. The system boundary polylines have attributes identifying the data source and the type of each boundary line, providing transparency and traceability. These datasets were developed through an iterative process that used GNS Science’s QMAP (a national GIS database of surface geology) as the primary input dataset, supplemented by other national datasets (e.g., topographic contours, regional surface drainage and aquifer potential). A method to ‘translate’ QMAP data into the national map of hydrogeological systems was developed in a pilot region (Southland); validated in a second geologically-contrasting region (Waikato); and then applied nationally to the remaining on-shore New Zealand. (auth)

Groundwater is an important source of water for the Wairau Plain. Concerns about its sustainable yield and contamination from nutrients have prompted several hydrogeological studies over time to better understand the groundwater system. The main aim of this study is the review and consistent interpretation of age-tracer, isotope and chemistry data, collected between 1968 and 2019, to obtain the hydraulic parameters necessary to understand the declining water levels and spring flows and to assess the groundwater storage that feeds the river and springs. (auth)

To help meet objectives set under the New Zealand Government’s National Policy Statement for Freshwater Management appropriate modelling tools are required to assist land and water management decision-making. The principal objective of the smart models for aquifer management research project (SAM) is to develop a decision-specific ‘smart’ modelling framework that takes into consideration modelling objectives and scenarios, available data and resources. Importantly, ‘smart’ models also consider the computational burden of large groundwater flow and transport models, including complexity and large scale, without compromising the reliability of decisions based on these models. Outputs from the research programme include development of methodologies to determine: (i) the modelling strategy which is most useful in a decision-making context; (ii) the data which is most useful in a decision-making context; and (iii) the gains and/or diminishing returns achieved with more data or more complex models. Three real-world case study catchments were selected: Hauraki (Waikato); Ruamahanga (Wellington), and Mid-Mataura/Waimea (Southland). This report collates and summarises community and stakeholder freshwater management objectives relevant to the three case study catchments derived from various engagement processes. Additional information has been obtained by interviews and consultations undertaken by the SAM project team. The information in this report provides the basis for selected resource management decision-support questions and scenarios to be tested in the SAM programme. (auth)

The National Institute for Water and Atmospheric Research established, and is leading, the 'National Hydrological Project (NHP), with GNS Science (GNS) and Landcare Research as sub-contracted partners. This report details the GNS activities in the NHP task "design and conceptualisation of catchment-wide isotopic data layers, including data-acquisition of isotope field samples, in selected case studies" and aims to refine isotopic data layers, for stable isotopes and tritium, to make them applicable for studies that estimate groundwater - surface water interaction at the catchment-scale. We describe the main activities carried out between May 2017 and May 2018: (1) the sampling design in three selected case study areas (Southland, Horizons and Gisborne regions) and associated collected water samples for NHP are described (with the first analyses results expected in the course of the next financial year 2018-19); (2) outline of the theory and rationale behind the sampling design; and (3) a review of existing tritium and stable isotope measurements, obtained outside the NHP, from both national and regional case study scale sampling programmes. The theory and review strengthen the rationale of the sampling design, and combined they lead to recommendations for further work, the most important of which is to align other streams of existing research to overcome the huge data sparsity resulting from using only data collected though the NHP, and to make the important step towards the national scale. (auth)