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The fate of pig slurry phosphorus applied to a sandy loam soil under no-till cropping in southern Brazil
No full textRepeated phosphorus (P) inputs can lead to the accumulation of surplus P in soil with enhanced potential risk of transfer and accelerated eutrophication of aquatic environments. Intensive pork production in Rio Grande do Sul in southern Brazil results in the generation of large quantities of P-rich waste in the form of pig slurry, which is used to fertilise crops. The aim of this study was to assess and quantify the impact of repeated application of pig slurry P over 8 years (2000–2007) on the fate of P in a sandy loam soil maintained under a mixed cropping regime. In a replicated field trial, pig slurry was applied at three rates (20, 40, and 80 m³ ha¯¹), which resulted in cumulative P inputs over the 8-year period of 628, 1256, and 2511 kg P ha¯¹. Slurry inputs of 20, 40, and 80 m³ ha¯¹ resulted in the accumulation of 368, 936, and 2039 kg P ha¯¹ in soil to 60 cm, respectively. A combination of soil storage (59–81 %), crop removal (7–14 %), and total P transfer in surface runoff (5–15 %) accounted for most of the P applied in pig slurry over 8 years. Our results highlight the potential environmental impacts of runoff P losses in long-term waste-amended and intensively managed subtropical coarse-textured soils. Measures to minimise soil erosion and P transfers from land to water bodies are of utmost importance
‘We now have Catholics and Blacks’: Whiteness in a Northern Irish rugby club
No full textNorthern Ireland is often considered in terms of the two majority communities, Catholics and Protestants, and the inter-communal conflict which structured, and continues to structure, much of Northern Irish society. However, situated within often volatile situations, the small ethnic minority communities of Northern Ireland have often been overlooked. This article investigates a Northern Irish rugby club, and examines the way in which whiteness is normalised, racist discourses are dismissed, and the sectarian boundaries, which are normally so strongly maintained, are overlooked in the presence of ‘others.’ As such, this research offers a contemporary perspective of the way whiteness, racism and sectarianism intersect in Northern Irish society, and starts a conversation about the provision of sport for ethnic minority communities in Northern Ireland
Supporting volunteer well-being through disaster: Perspectives and practices of a youth-led informal crisis volunteer group
No full textEmbedded in growing expectations for post-disaster volunteer participation are questions of volunteers’ psychological well-being. Witnessing destruction and suffering, and the intense pressures of the work itself, can place heavy demands on crisis volunteers, particularly in “informal” community groups that may lack the structure, systems, and supports embedded within “formal” disaster response organizations. This article examines how the Student Volunteer Army in Aotearoa New Zealand has negotiated volunteers’ well-being across two disaster responses: an earthquake in 2011 and terrorist attacks in 2019. We identify three interrelated practices adopted by the group to support well-being: “action” (enabling opportunities for people to engage in volunteering); “reflection” (facilitating processes of discussion and debriefing); and “connection” (creating physical space and practices to enhance social interactions). Our discussion considers the implications of multi-layered practices of support that can develop within informal crisis volunteer groups
Chronically stressed benthic macroinvertebrate communities exhibit limited effects on ecosystem function in a microtidal estuary
No full textAnthropogenically driven alterations to coastal sediments and their benthic macroinvertebrate communities impair ecosystem function. However, this paradigm is yet to be tested in ecosystems that typically harbour underdeveloped communities lacking larger bioturbating species. Here, we investigated the effects of sediment condition and macroinvertebrate communities on benthic metabolism, nutrient exchange and denitrification (N₂ production), and assessed the relative importance of taxon richness, abundance, biomass and community bioturbation potential in influencing these processes in 2 regions of the highly modified, microtidal Peel-Harvey Estuary in temperate Western Australia. Sediment condition influenced benthic metabolism more than the macroinvertebrate community, whereas the reverse was true for nutrient exchange. Denitrification was driven by sediment condition and the community in the upper and lower estuary, respectively, highlighting the change in controls of this nitrogen-removal process within estuaries. Overall, benthic macroinvertebrates had little to no effect on many ecosystem processes, exhibiting the limited functional role played by these chronically stressed biota in this estuary. There was also no interaction between sediment condition and the community, suggesting a functional decoupling between these 2 ecosystem components. Where significant macroinvertebrate effects were detected, community biomass was the most frequently selected predictor, demonstrating its fundamental role in ecosystem function. This study reveals pressing implications of what might be expected when benthic environments become particularly degraded and the highly limited potential of the resultant benthic macroinvertebrate communities to provide key ecosystem services such as nutrient processing
Measuring landscape performance for a subdivision in Canterbury, New Zealand: Reflections and critique of methods
No full textCompleted in 2019, Te Whāriki (Phase 1& 2) is a 144-acre residential subdivision adjacent to Lincoln University in Canterbury, New Zealand. The project transformed a dairy farm into a high-performance residential landscape featuring a series of constructed wetlands. According to its design goals, Te Whāriki is expected to help support local biodiversity, improve downstream water quality, reduce car dependence, encourage the use of alternative transport, and provide opportunities for food collection and harvesting. With support provided by the Landscape Architecture Foundation (LAF) and the design firm - Earthwork Landscape Architects, we measured the actual performance of Te Whāriki, as a part of the 2021 LAF Case Study Investigation (CSI) programme.
A series of performance metrics were firstly selected according to the design goals and other associated benefits. The selected metrics include the number of observed species, frequency of using cars and alternative transport, and pollutant load reduction. These metrics were then evaluated by using a range of methods, including a resident survey, on-site measurements, and the Pathfinder landscape carbon calculator. Apart from these standardised CSI evaluation methods, we have also applied some innovative or modified methods as many standardised CSI methods are developed in the North American context, with embedded North American standards or requiring specific datasets that are not available in New Zealand. These innovative and modified methods include iNatualist data queries, a modified System for Observing Play and Recreation in Communities (SOPARC), and a modified Watershed Treatment Model (WTM).
The evaluation results show that Te Whāriki generally performs well and has met most of its design goals. We also found that the wetlands and walking tracks within the residential landscape are significant in encouraging the residents to exercise more, and contribute to their self-reported improved mode and quality of life. The evaluation also identified lessons learned from the management and maintenance practices, including the need for more interpretive information regarding the use of edible elements of the landscape.
This presentation aims to 1) share the key findings and lessons learned from this evaluation, 2) highlight the innovative and modified evaluation methods we applied in our evaluation, and 3) building upon past discussions related to the CSI evaluation framework (De Almeida & Lopresto, 2019; Yang et al., 2016), offer a series of reflections on the CSI framework, related to broader issues around landscape performance evaluation practices. By sharing these findings and reflections, we hope to catalyse further conversations on the current evaluation framework and contribute to its further iteration and improvement
Physicochemical variables better explain changes in microbial community structure and abundance under alternate wetting and drying events
No full textSoil microbial communities play an important role in nutrient cycling; however, their response under repeated long-term fertilization has attracted little attention and needs further appraisal. A 14-day incubation study compared the relative abundance, diversity, and composition of bacterial and fungal microbial communities in soils treated with long-term applications of chemical fertilizer (CF), pig manure plus chemical fertilizer (PMCF), and rice straw plus chemical fertilizer (SRCF) in a paddy field. A high-throughput sequencing approach was applied to assess the diversity and composition of microbial community. Results revealed the Shannon index of the bacterial community decreased with fertilizer addition but increased in case of fungal community. The abundance of the Actinobacteria was higher in the PMCF, while Proteobacteria were higher in the CF and SRCF treatments than those in the unamended control under alternate wetting and drying (AWD) and permanent flooding (PF). In addition, chemical fertilizer history increased the abundance of Firmicutes under AWD. Initially, Nitrospira were found higher in the unamended control than in the amended treatments, but an increase was observed with time in fertilized treatments. Among all genera, Proteobacteria were the most abundant bacterial genus. The main properties that markedly affected the bacterial communities were SOC (R² = 0.4037, p < 0.02), available P (R² = 0.3273, p < 0.05), and NO₃− (R² = 0.3096, p < 0.08). Soil physicochemical factors and biogenic factors explained a variation of 46.27% and 29.35%, respectively. At the same time, 4.59% was the combined effect of physicochemical and biogenic factors. Our results suggested that the physicochemical properties had a more significant impact on bacterial activities than water regime by increasing N and organic matter concentrations in the soils
δ¹⁸O as a tracer of PO₄³¯ losses from agricultural landscapes
No full textAccurately tracing the sources and fate of excess PO₄³¯ in waterways is necessary for sustainable catchment management. The natural abundance isotopic composition of O in PO₄³¯ (δ¹⁸OP) is a promising tracer of point source pollution, but its ability to track diffuse agricultural pollution is unclear. We tested the hypothesis that δ¹⁸OP could distinguish between agricultural PO₄³¯ sources by measuring the integrated δ¹⁸OP composition and P speciation of contrasting inorganic fertilisers (compound vs rock) and soil textures (sand, loam, clay) in southwestern Australia.δ¹⁸OP composition differed between the three soil textures sampled across six livestock farms: sandy soils had lower overall δ¹⁸OP values (21 ± 1‰) than the loams (23 ± 1‰), which corresponded with a smaller, but more readily leachable, PO₄³¯pool. Fertilisers had greater δ¹⁸OP variability (∼8‰), with fluctuations due to type and manufacturing year. Consequently, catchment ‘agricultural soil leaching’ δ¹⁸OP signatures could span from 18 to 25‰ depending on both fertiliser type and timing (lag between application and leaching). These findings emphasise the potential of δ¹⁸OP to untangle soil-fertiliser P dynamics under controlled conditions, but that its use to trace catchment-scale agricultural PO₄³¯ losses is limited by uncertainties in soil biological P cycling and its associated isotopic fractionation
Debating racial hierarchy and the exclusion of Māori from the 1928 All Blacks Rugby tour to South Africa
No full textThe announcement by the New Zealand Rugby Football Union in 1927 that no Māori players would be selected for the following year’s All Blacks tour to South Africa, prompted heated debate within New Zealand. While some insisted that the Union should not send a team unless it was fully representative of a country in which Māori and Pākehā apparently enjoyed very harmonious relations, others argued that the exclusion was necessary to protect Māori from the endemic race problems and white prejudice of South Africa. This debate points to a much longer, and more nuanced, history of disputes over sporting contacts with South Africa than has been generally recognised. It also reveals much about New Zealand perceptions of race and racial hierarchies in the inter-war British Empire and the role of certain Māori leaders in shaping and reinforcing these attitudes
How many gigabytes per hectare are available in the digital agriculture era? A digitization footprint estimation
No full textThe applications of digital agriculture technologies are increasing rapidly with increased interest from the new generation of farmers to use digital solutions. Such technologies include several in-field and remote sensors besides data processing software packages. The accumulation of archived data from season to season has become an issue considering the high spatial and temporal resolution of the generated data from the commercially available sensors. Therefore, the aim of this study was to evaluate and quantify the accumulated data considering the evolution of utilized digital solutions from a farmer's case study. This study estimated the data storage disc space requirements in the last two decades from a 22 ha field located in North Italy. The farmer's accumulated data sources were from an in-field weather station, soil analysis information, soil apparent electrical conductivity scanning, soil moisture sensor, planter performance monitoring system, yield maps, Sentinel-2 satellite images, and recently drone images. The accumulated data were reported on an annual basis with respect to each year's specific contribution. The results showed that the total accumulated data size from the study field reached 18.6 GB in 2020 mainly due to the use of drone images with a predicted total data size of 40.5 GB by 2025
Diverse forms of xylem-like cells and strand formation in Xylogenic Eucalyptus bosistoana callus culture
Get PDFIn vitro xylem induction system is a basic tool in physiological, biochemical, and molecular studies of secondary cell wall formation, lignin biosynthesis and deposition associated with tracheary element formation. Eucalyptus bosistoana is a Class 1 durable hardwood tree species, selected by the New Zealand Dryland Forest Initiative for good quality wood and high adaptability to the NZ growing conditions. Xylogenic E. bosistoana callus culture was established and up to 40% of the callus cells were xylem-like cells (XLCs) which may have differentiated from small, cytoplasmically dense or compact dividing, and exhibited increased lignin contents during culture. The eucalyptus XLCs showed diverse sizes, patterns of secondary cell wall thickenings similar to the xylem cells in the young shoots and organized development including cell–cell connections of the XLCs to form xylem strands. This is the first report of the organized development of XLCs in E. bosistoana callus culture