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Harnessing spider biodiversity for sustainable horticulture: A call for research and conservation in Aotearoa New Zealand
No full textThe world is facing many pressing issues around food production and environmental sustainability. We are living in the sixth mass extinction event, driven by human activities including agricultural intensification, which has significantly affected invertebrate biodiversity. To address these issues, many scientists, growers, and policy makers are moving towards Integrated Pest Management (IPM) and restoring or creating natural or semi-natural habitats adjacent to or within food production ecosystems to conserve biodiversity whilst maintaining agricultural production. Despite spiders being the dominant, most abundant, and most diverse natural enemies of pests in horticultural ecosystems, their potential contribution to pest management has been understudied in Aotearoa | New Zealand. Internationally, many studies have shown the positive effects that spider abundance and diversity have on economically important food production systems, and many studies have demonstrated that enhancing adjacent habitat can conserve the biological control provided by spiders in these productive ecosystems. We highlight international studies that show positive effects of spider conservation on biological control in agroecosystems and discuss the few studies that have been completed on spiders in agriculture in Aotearoa | New Zealand. To date, only eight studies of spiders in agroecosystems have been published from Aotearoa | New Zealand and only a single study published on spiders in New Zealand horticultural ecosystems despite horticulture being a significant export market to countries that demand low chemical residue practices. All eight of these studies have been surveys of spider abundance and richness found in these systems, with a gap remaining in measuring the ecosystem functions they provide. We call for greater investment into research on spider conservation for biological control in Aotearoa | New Zealand to maximise the potential for ecologically friendly productive system
What has happened to our lake? Characterizing the development of Kahphuche Lake in Nepal : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Applied Science at Lincoln University
No full textThe unfolding of Kahphuche Lake in the Himalayan foothills of western Nepal in less than two decades, at an elevation of 2,450 meters above sea level (m asl), below the accepted lower limit of glacier moraine accumulations in Nepal (i.e., 3,500 m asl) has provoked many questions and confusion regarding its glacier origins and future implications. Given the geographical complexity of seasonal and topographic variations of rugged terrain, coupled with the lack of extensive literature, it is a challenge to understand the development and dynamics of Kahphuche Lake. Thus, the principal aim of this study is to provide an in-depth insight into Kahphuche Lake’s formation and growth, classification, and its broader implications from an interdisciplinary approach.
Two key sources of knowledge are integrated in this research – physical science methods using remote sensing and spatial data analysis, and qualitative insights obtained through key informant interviews. Merging remote sensing data with local knowledge that has been shaped by generations of lived experience who themselves have witnessed the lake’s evolution over time becomes indispensable in filling the gaps, providing a deeper perspective of Kahphuche Lake Catchment, its changes, and the underlying factors driving its formation and growth.
Results revealed that Kahphuche Lake's formation is not limited to environmental components like glacier retreat and glacial meltwater. While previous studies attributed the formation of Kahphuche Lake to the accumulation of meltwater from avalanche deposits, this study strongly suggests that the debris- covered glacier origins of Kahphuche Lake make it a proglacial lake. The qualitative findings also serve as a powerful interpretive tool, enriching and validating the remote sensing analysis while highlighting how local communities perceive this lake as both a marker of environmental change and a cultural and livelihood resource. Consequently, challenging the conventional narrative of glacial lakes forming at elevations higher than 3,500 m in the Nepal Himalayas, the development of Kahphuche Glacial Lake at 2,400 m asl offers a new outlook on the region’s past glacial history and ongoing environmental change in an increasingly dynamic Himalayan landscape
Multi-purpose data worth assessment of a surface water-groundwater and nitrogen transport model
No full textUnderstanding which hydrological data types provide the most valuable information for models is crucial, given the limitations of data availability. This study applies data worth analysis to evaluate the impact of various observation types on predictive uncertainty in a coupled SWAT-MODFLOW-RT3D model simulating water flows and nitrate transport in a small headwater catchment in New Zealand. We assessed the worth of continuous nitrate concentrations, in-catchment flow measurements, and SkyTEM-derived groundwater levels for predicting stream flow and in-stream nitrate concentrations. Using PEST software for model calibration and linear uncertainty analysis, we determined the relative worth of different observation types. Results indicate that SkyTEM estimates of groundwater levels and continuously measured nitrate concentrations were particularly effective in reducing predictive uncertainty. This study highlights the value of integrating high-resolution SkyTEM data into models to enhance prediction accuracy for groundwater levels, stream flow, and nitrate pollution. It also demonstrates nitrate's utility as an environmental tracer, refining our understanding of surface water–groundwater interactions and solute transport in the Piako Headwaters Catchment
Withdrawal, restraint, attention, and repair: Strategies of careful design in the landscape
No full textThe legacy of modernism in the designed landscape has often been characterised by strongly formalist, imposing projects which are unflinching in the face of temporality. Dominated by the visual and the evident hand of the designer, these muscular works are expressions of excess, that this paper classifies as ‘strong’ design. Alongside this are the decades of consumerism driven by fashion cycles and a predilection for the new, rather than slow design and investment in objects which can be repaired rather than discarded. However, there is an emerging ethos in design that favours a counter approach, emphasising restraint, modesty and frugality, and echoing the tenet of ‘weak’ or ‘fragile’ philosophies. This paper draws together a wide range of allied approaches to designing landscapes and offers an inventory based around four attitudes towards careful design: withdrawal, restraint, attention, and repair
Asynchronous accumulation of sugar and phenolics in grapevines following post-veraison leaf removal
No full textClimate change necessitates the re-evaluation of viticultural practices to manage increasing grape sugar concentrations and meet consumer demand for lower-alcohol wines. This study aimed to evaluate whether modifying the leaf area to fruit weight (LA:FW) ratio through shoot trimming could reduce sugar accumulation while maintaining phenolic quality in Pinot noir grapes. We examined both the timing and severity of canopy reduction, implementing shoot trimming treatments (half canopy, H, in 2015–2016 and 2016–2017, and quarter canopy, Q, in 2016–2017) at three stages: pre-veraison (V–, E-L 34), veraison (V, E-L 35), and post-veraison (V+, E-L 36) across three vineyard locations. In each trimmed treatment (H or Q), lateral shoots were removed concurrently with shoot trimming to maintain consistent leaf area. Our results show that reducing the LA:FW ratio through trimming delayed and reduced grape sugar accumulation. Phenolic responses, however, varied by timing: early trimming (V–, V) decreased anthocyanin concentration at harvest of up to 37 % in QV– vines compared to controls, primarily due to reduced accumulation rates. In contrast, late trimming (QV+, HV+) maintained the concentration of anthocyanins at harvest and at target soluble solids and preserved anthocyanin-to-sugar ratios similar to the control. Total phenols, seed and skin tannins were unaffected by trimming, particularly in QV+ and HV+ treatments. Therefore, while these treatments decreased soluble solids, these phenolic components remained unchanged. Our results demonstrated that post-veraison (V+) shoot trimming could be a promising strategy to produce darker-colored berries at lower sugar concentrations. Therefore, trimming post-veraison but early in the maturity phase (~15 °Brix) to half-canopy level (HV+), represents a more sustainable approach for achieving dark-colored grapes while maintaining unaltered phenolic profiles at lower sugar concentration
Microbial adaptations to acidic, nutrient- and metal-rich lakes in Aotearoa New Zealand
No full textFour lakes in the same region of Aotearoa New Zealand were investigated to characterize sediment microbial communities and functions under contrasting environmental conditions. Two lakes, an acidic lake (Rototai) and a lake with elevated metals and nutrients (Killarney) were impacted by extreme stressors, while the lowland mesotrophic lake (Kaihoka East) and an alpine lake (Peel) were used as reference lakes. Using metabarcoding and metagenomics analysis, we profiled community composition, functional pathways, and resistance mechanisms in the lake sediments. Rototai contained high abundances of genes involved in sulfur cycling (assimilatory and dissimilatory sulfate reduction, sulfur oxidation) and acid tolerance (kdp potassium-transport system, ClcA antiporters). In contrast, Killarney had elevated abundances of genes involved in methanogenesis, however despite high metal concentrations, no enrichment of metal-resistance genes was detected. Kaihoka East contained the highest prokaryotic diversity and an elevated abundance of genes involved in nitrification. Although community taxonomic differences were modest across lakes, functional analyses revealed distinct metabolic adaptations. These findings highlight the utility of using metagenomic approaches to identify biogeochemical processes and stress-response strategies in lakes. Improved understanding of microbial functional diversity in surface sediments has implications for lake management, particularly in systems impacted by acidification, high nutrient loading, and metal contamination
Exploring the performance of jackfruit seed starch and protein microcapsules as probiotic carrier systems: enhancing viability, shelf life, and gastrointestinal resilience
No full textConventional encapsulating materials like maltodextrin, gelatin, casein, and synthetic polymers face challenges such as instability in gastric conditions, high costs, and ethical concerns. As sustainable alternatives, starch-based polymers and protein isolates offer superior protection, biocompatibility, and eco-friendliness. This study is aimed at supporting Sustainable Development Goals by utilizing jackfruit seed starch (JSS) and protein isolate (JSPI) for the microencapsulation of Lactiplantibacillus plantarum. The encapsulation efficiency ranged from 82.87% to 96%, also enhancing cell viability to 1011–109 CFU/g. SEM analysis confirmed the formation of microcapsules (7–30 μm) without free cells. Thermal analysis showed endothermic peak temperatures of 78.4°C–87.5°C, indicating resilience to food processing conditions. Microencapsulation with JSS and JSPI improved probiotic survival up to 8 log CFU/g for 28 days and 7 log CFU/g in gastrointestinal conditions. These findings suggest that JSS and JSPI are promising, sustainable materials for probiotic microencapsulation in food application
Comparing energy intake estimates derived from using respiratory gas flux measurements with backward dietary energy partitioning for beef cattle
No full textThe objectives of this experiment were to refine the use of open-circuit gas-quantification methodology to estimate energy intake by ruminants and compare 4 different approaches to account for urinary N (UN) excretion. Eight cross-bred beef steers with a beginning body weight (BW) of 244 ± 15.1 kg were used in a 77-day feeding experiment. Steers were assigned to 1 of 3 multiples of the calculated metabolizable energy (ME) requirement at maintenance (10.7 megacalories of ME), which are 1.1 x maintenance, 1.4 x maintenance and 1.8 x maintenance. Diets were long-stemmed wheat (Triticum aestivum L.) hay and supplemental alfalfa (Medicago sativa) pellets. Respiratory gas fluxes were measured using an automated head chamber system (AHCS; GreenFeed, C-Lock, Inc., Rapid City, SD, USA). Urinary N excretion was accounted for with 1 of 4 approaches and included estimating UN excretion using prediction models based on either 1) diet quality and dry matter intake, 2) BW, 3) assuming a constant value centered on the average of the 2 model estimates (60 g/day), and 4) assuming UN excretion to be 0. Pearson correlations between estimated gross energy (GE) (r = 0.95), digestible energy (DE) (r = 0.88), and ME intake rates and measured values were highly positive (r = 0.85) regardless of the approach used to estimate UN excretion. Approaches to estimate UN excretion differed by 0.81 % at the most when calculating ME intake and concordance of correlations coefficients showed good or better agreement between the estimated and measured GE, DE, and ME intakes (rc ≥ 0.45). This experiment confirmed that short-term breath measurements from an AHCS, together with BW change, can be used to estimate GE, DE, and ME intake by cattle
On the monophyly of Porrhothele antipodiana (Porrhothelidae: Mygalomorphae) and a new species of Porrhothele from Banks Peninsula
No full textPorrhothele (Mygalomorphae: Porrhothelidae) is a genus of tunnelweb spider endemic to New Zealand. The most frequently encountered species, Porrhothele antipodiana, is widespread throughout New Zealand and it has been suggested that it might represent a cryptic species complex. A phylogenetic hypothesis was generated using sequences of mitochondrial DNA cytochrome oxidase 1 from specimens collected throughout New Zealand. The genetic evidence suggests that P. antipodiana comprises a single widespread species consistent with morphological evidence. However, additional novel lineages were revealed by the analysis for which morphology suggests the presence of undescribed species. One of these, Porrhothele peninsularis sp. nov. is described
The social world and event travel careers of leisure marchers
No full textSport has been the context for a considerable number of studies on social worlds and event travel careers, with most focusing on individual competitive sports. The inherently social nature of team sport participation thus offers a potentially rich area of study. This study addresses this gap and responds to calls for more research on older women’s team sport, through an investigation of the unique sport of leisure marching. It examines how the social world and event travel career differs from individual competitive sports, and how these social practices are intertwined with notions of age and gender. Data was collected through participant observation and interviews and was subjected to qualitative deductive thematic analysis using Unruh’s (1979, 1980) social world concept. Findings highlight commonalities with, and distinctiveness from, individual competitive sports social worlds and reveal gender-and age-related nuances – particularly around the social world aspect of events