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Diffusive gradients in thin-films (DGT) in soil science research: Review of the last 25 years
No full textThe diffusive gradients in thin-films (DGT) technique was originally developed for use in natural waters to measure the elusive “free” trace metal ion. It was quickly adapted for use in aquatic sediments and soils to measure trace metal and phosphorus fluxes, and the first scientific article reporting its use in soils was submitted for publication 25 years ago. The technique showed early promise as a reliable measurement of plant available trace metal in soils and it was first used for that purpose on Aotearoa soils in the late 2000s. It has since been adapted to measure a variety of different analytes, in expanded dimensionality and simultaneously with measurements of other dynamic soil variables (e.g. pH, enzyme activity). The insight gained in the last quarter of a century of DGT research will be used to re-examine some of the early assumptions about the information it can provide. The presentation will go on to highlight some new and interesting applications for both applied and theoretical soil scientists in Aotearoa. There are clearly important challenges to understanding what the results of DGT measurements in some soils represent. However, increased knowledge of processes that influence the supply of nutrients and trace elements to DGT presents new opportunities to investigate biogeochemical cycling in soils in ways that are not possible with most other techniques. This provides interesting prospects for future soil research where the technique can play a unique and important role
Nitrogen fertilization effects on soil phosphorus dynamics under a grass-pasture system
No full textNitrogen (N) and phosphorus (P) are critical to pasture productivity; however, limited information is available on how the single and combined additions of N and P affect soil P fractions and seasonal changes in microbial and biochemical processes linked to P cycling under pasture systems. A two-year field trial was conducted where N (0 or 250 kg ha¯¹yr¯¹) and P (0 or 50 kg ha¯¹yr¯¹) were applied in a full factorial design to an intensively managed grass-pasture system. Changes in plant growth and nutrient uptake, soil microbial biomass P, soil phosphatase activities, and soil inorganic and organic P fractions were assessed by regular sampling. Phosphorus addition increased Olsen P and shoot P uptake but not shoot biomass compared to the control. In contrast, N addition decreased Olsen P by 23% but increased both shoot biomass and P uptake by 1.6-fold, compared to the control. Microbial biomass P was irresponsive to N and P additions. Phosphatase enzyme activity significantly increased in summer under N addition, which was linked to labile organic P mineralization. After two growing seasons, N addition alone significantly decreased readily-available inorganic P, labile inorganic P, moderately labile inorganic P, and labile organic P by 75, 19, 7, and 28%, respectively, compared to the control. On the other hand, combined N and P addition significantly decreased readily-available inorganic P, labile inorganic P, and labile organic P by 39, 26, and 28%, respectively, but had no impact on moderately labile inorganic P compared to P addition alone. The findings of this study revealed that short-term N fertilization to N-limited grass-pastures can accelerate P cycling by mobilizing labile inorganic and organic P as well as moderately labile inorganic P pools. However, N fertilization combined with P applications exceeding plant requirements cannot mobilize moderately labile inorganic P, which accumulates under high P sorbing soils
Industrial transfer, socioeconomic development and environment: an empirical analysis of China : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
No full textSince 2000 the central government of China has followed a policy of moving industries from Eastern provinces to Central and Western provinces. The primary goal of this policy is to decrease economic disparity within the country, and cross-regional industrial transfer has become a significant driving force in achieving economic growth for inland China. However, in most cases, industrial transfer has resulted in the degradation of the environment. This situation increases the external costs for the economic development of the inland regions and influences the environmental quality, which has been the main obstacle to regional sustainable development. This thesis provides an impact analysis of the industrial transfer on the social economy, the environment and sustainable development for the transfer-in provinces. It is an important basis for rationally guiding industrial transfer in the interior regions and scientifically formulating industrial transfer policies as the basis for maintaining sustainable regional development.
To investigate the impacts of industrial transfer, spatial empirical models are applied to examine the effect of industrial transfer on socioeconomic performance, and the environmental outcome. A coupling coordination degree and a three-dimension model are designed to explore the impact of industrial transfer on sustainable regional development. This study used provincial-level panel data covering 2000-2015.
The results show that industrial transfer is beneficial to promote the development of recipient provinces and increasing the disposable income of local residents. However, the industrial transfer did not decrease the relative income disparities between the recipient provinces and the wealthier eastern region. On the other side, industrial transfer increased the total amount of pollution emissions, for example, waste gas, wastewater, and solid waste (three wastes). Industrial transfer can increase industrial pollution. However, after the eleventh Five-Year plan, some main pollutants, such as chemical oxygen demand (COD) and sulphur dioxide (SO2)experienced a major decline. The empirical results showed that industrial transfer had not resulted in an increase in the main industrial pollutants. Moreover, the industrial transfer had not an apparent effect on expanding of environmental disparity between recipient provinces and the eastern region. Through the analysis of the relationship between industrial transfer, socioeconomic development, and environmental quality, increasing the industrial transfer can improve sustainable regional development. However, for the remote areas, such as Inner Mongolia, Xinjiang and Qinghai, the environmental quality declined significantly with the industrial transfer.
Considering all the effects of industrial transfer, a key of the research was to understand the impact of the industrial transfer policy. The promotion of industrial transfer for the sustainable development of a region needs to move from increasing quantity to improving the quality of the industrial transfer. In vigorously introducing industrial transfer, it is clear that attention also needs to be paid to the protection of environmental quality to achieve the sustainable development of the regions receiving the industrial transfer
An examination of human capital investment, employee productivity and return on investment: The case for the New Zealand hotel industry : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
No full textThis study investigated the relationships between Human Capital Investment (HCI) in the New Zealand hotel industry, its impact on Employee Productivity (EP), and the Return on Investment (ROI). Previous research into HCI, EP and ROI has not considered these factors as being interdependent especially in the area of tourism.
Pre-Covid-19, tourism (including the hotel sector) in New Zealand was a primary driver of the economy. The industry has strong growth prospects despite the current pressures facing the global tourism industry. HCI plays a significant role in the growth of this industry. Hotels believe that their human capital is their most valuable asset and highest operational cost, and agree that HCI is fundamental to sustain business growth. Such investment can take many forms, from initial engagement to ongoing training and education, to ensure employees are as productive as possible. However, literature in the tourism industry reports that productivity research and analysis has not received the attention needed despite being a high priority on the United Nation World Travel Organisation (UNWTO) agenda. In effect, this is a call for more research into tourism productivity related to EP, HCI and HCROI. When businesses, including hotels, invest in their Human Capital (HC) they expect to generate a return that needs to be quantified. ROI measures the cost-efficiency of investment by analysing the financial gain or loss made by the investment relative to the amount of money spent. Therefore, it was particularly important to understand how HCI impacted on productivity and how this was then measured against a ROI.
This research used a mixed-methods approach. In-depth semi-structured interviews were conducted with 25 general and operational hotel managers to gain their understanding of HCI, EP, and ROI and how these were measured and tracked. An online questionnaire gathered data from 102 hotel employees on their understanding of the term EP and factors that increased or decreased their productivity. The study participants were from 18 international and domestic brands of hotels within three- to five-star hotels in three locations in New Zealand: Auckland, Christchurch, and Queenstown.
This research found that investment in the pursuit of productivity is viewed differently by employees, operational and general managers. Each group also has a different view on how to measure productivity. The most striking finding of this research is that hotels do not measure HCROI. ROI measures the cost-efficiency of investment; therefore, the lack of understanding of ROI by hotel managers and senior hotel head office human resource directors is a new understanding and of particular importance and concern. These interconnected findings have not previously been considered or reported in the literature. Overall, a key message for industry practitioners and hospitality researchers is that they should work together to co-produce research that will help managers better understand ROI and its calculation.
While HCI to EP might be considered a logical and linear process, for hotels in this research, it does not then move to consider ROI. This disconnect and consequently the missing loop from ROI back to discussions about future HCI add to the body of knowledge of how hotels consider their human capital. This thesis contributes to the hotel industry and literature
Effects of a polysaccharide extract from Amomum villosum Lour. on gastric mucosal injury and its potential underlying mechanism
No full textAVLP-2, a novel acidic polysaccharide, was isolated and purified from Amomum villosum Lour. The structural characteristics of the polysaccharides were characterized using monosaccharide composition, methylation, FT-IR, and NMR techniques. Results showed that AVLP-2 comprises galactose and glucose monomers, has a molecular weight of 10.488 kDa, and has backbone structures →4)- α-D-GalAp-(1→3,4)- α-D-GalAp-(1→, →4)- α-D-GalAp-(1→6)- α-D-Galp-(1→, and n→6)- α-D-Galp-(1→4)-β-D-Glcp-(1→, with α-D-Galp-(1→ branches. Furthermore, AVLP-2 had a significant protective effect against oxidative stress in alcohol-induced injury and LPS inflammation models GES-1 cells by regulating the levels of ROS and inflammatory factors. In the animal experiments, AVLP-2 improved the oxidative stress status of the gastric mucosa by increasing SOD activity and GSH levels and inhibiting the excessive generation of malondialdehyde in tissues. The levels of MPO, IL-1β, IL-10, and NF-κB p65 were downregulated, while that of TNF-α was upregulated by AVLP-2 treatment, thereby reducing the alcohol-induced inflammation
Is there a connection between psychological ownership and entrepreneurial resilience?
No full textThe vulnerability of SMEs was a primary concern for policymakers across the globe following the disruptions posed by COVID-19 as SMEs form an essential part of the economy; hence, their resilience has become an important topic for research and discussion. Within SMEs, entrepreneurial firms are an indispensable group and management literature has highlighted that ownership acts as a source of competitive advantage for organisations. Through this research, we wanted to explore the relationship between psychological ownership and entrepreneurial resilience. A systematic literature review revealed that psychological ownership and entrepreneurial resilience are linked through the individual’s cognitive, effective and emotional attributes
Yield gaps of lucerne (Medicago sativa L.) in livestock systems of Argentina
No full textArgentina grows the second-largest area of lucerne in the world. Despite its importance, a yield gap exists between potential and measured yields, but factors contributing to it are still unclear. This study aimed to identify management factors and research needs to reduce the lucerne yield gap to improve the livestock systems in this region. We used meteorological data coupled with lucerne crop modelling and measured yields from the National Lucerne Cultivar Evaluation Network (NLCEN) to quantify the lucerne yield gap in nine sites located within the Argentinian Pampas (between parallels 30–45°S and meridians 58–65°W) and three sites outside the Pampas. Specifically, we used the model developed by McCall & Bishop-Hurley (2003), adapted and calibrated for lucerne in Argentina by Berone et al. (2017) to estimate the potential yield (PY) for 12 locations (three irrigated and nine rainfed), and compared those results with measured yields from the NLCEN to calculate yield gaps. We found the average available photosynthetic active radiation (PAR) and temperatures were sufficient to achieve 21.5 ± 3.7 t dry matter (DM) ha¯¹ yr¯¹ under rainfed conditions (environments with mean annual rainfall from 400 to 1,200 mm). However, the average measured yield from the NLCEN was 16.8 ± 2.4 t DM ha¯¹ yr¯ (a 22% gap). Potential yields ranged between 10 and 25 t DM ha¯¹ yr¯¹under rainfed conditions and between 25 and 39 t DM ha¯¹ yr¯¹ for irrigated crops. As latitude increased rainfed locations had lower yields, while irrigated locations had higher yields. Adding irrigation was predicted to increase yields to 35.4 ± 2.0 t DM ha¯¹ yr¯¹ (a 53% gap) in rainfed sites. For irrigated locations, the gap was smaller (27.3 ± 3.5 vs 32.4 ± 2.2 t DM ha¯¹ yr¯¹ for measured vs potential yield, respectively), and most likely linked to nutrient deficits. Also, current grazing management was estimated to achieve approximately 50% less grazing efficiency than optimal grazing management. Our results demonstrated that the livestock industry can potentially increase animal production under current environmental conditions. The four main adjustments to achieve this are increased use of irrigation, increased use of fertilisers, earlier commencement of grazing in spring and increased stocking rates. The costs of irrigation, fertilisers and grazing management are envisaged to be small compared with potential increases in incomes and thus profitability available to beef and dairy farmers using lucerne as a major feed source in Argentina
Genome-wide epigenetic changes during and following grapevine somatic embryogenesis
No full textSomaclonal variation is a proven source of genetic diversity and is of particular interest in cases where breeding is not a suitable route for crop improvement. Novel sequencing techniques can enhance this approach by enabling the rapid genotypic characterisation of large populations of regenerated plants before phenotypes are expressed. We have been producing novel grapevine somaclones using somatic embryogenesis. However, the stress of tissue culture can alter the epigenetic state of plant cells in a way that may persist in regenerated plants. To study the epigenetic changes induced by this process, we performed bisulphite sequencing on embryogenic callus (EC) and plants regenerated from EC. Compared with leaf material, we found that EC had increased cytosine methylation, particularly in the asymmetrical CHH context, which is indicative of de novo methylation. However, genes and transposable elements (TEs) within genes showed reduced TEspecific CHG methylation. Plants regenerated from EC showed hypermethylation across all cytosine contexts three years after tissue culture. Interestingly, when EC were treated with the demethylating compound 5-Azacytidine, regenerated plants showed higher methylation than those from untreated callus, particularly in CG and CHG contexts. These data suggest that demethylation of TEs during somatic embryogenesis triggers de novo hypermethylation that is stabilised across symmetric cytosine contexts, and which persists years into the future. Based on these results, nanopore-based genotyping efforts are being adapted to include methylation calling, so that the functional impact of epigenetic changes can be determined in somaclone
Governing taste: Data, temporality and everyday kiwifruit dry matter performances
No full textData is essential to governing those emerging matters of concern that confront the agrifood every day. But data is no neutral intermediary. It disrupts, exposes, and creates new social, economic, political, and environmental possibilities, whilst simultaneously hiding, excluding, and foreclosing others. Scholars have become attuned to both the constitutive role of data in creating everyday worlds, and the need to develop critical accounts of the materialities, spatialities and multiplicities of data relationships. Whereas this emerging work develops insight to the capacity for data topologies to reterritorialise the spatial performances of everyday life, it has largely reduced the associated temporal dimensions to matters of fact. The efect of these performances has been to naturalize the temporal quality of speed and elide the multiple temporalities required to enact contemporary data worlds. Applying the lenses of infrastructuring, performativity and ferality, this paper explores temporality and data in the everyday worlds produced through the New Zealand kiwifruit industry’s focus on dry matter. The paper argues that temporalities are deeply embedded in the kiwifruit industry’s data relations. We show that while temporal data relations are critical to the industry, we also highlight ways in which those relations introduce new, potentially destabilizing performances into kiwifruit relations
Impact of GlobalGAP compliance on cost of production in small-scale pineapple farming in Ghana
No full textIntroduction. Food safety standards play a critical role in governing global food production and trade. They ensure that food is produced, processed, and distributed under hygienic and safe conditions. Notable among them is GlobalGAP, which is implemented globally and widely recognised as the most important voluntary food safety standards in the fresh produce industry. Although GlobalGAP compliance has enhanced hygienic and safe food production in Ghana and other developing countries, adoption rates have been low among smallholders. Previous studies have identified cost of GlobalGAP compliance as the key constraint hindering its uptake by smallholders. However, little research has been done to attribute this increase in cost to specific inputs used by farmers. Such information would help policymakers to target interventions at the most important drivers of quality-enhancing compliance costs and make adoption of GlobalGAP more affordable to small-scale farmers. This study analyses the cost of pineapple production for GlobalGAP certified smallholders in Ghana.
Data and methods. The study relied on household and farm-level data to investigate the research problems. A multistage sampling approach was used to select districts, communities, and small-scale pineapple farmers. Data were solicited via a field survey of 236 GlobalGAP certified small-scale pineapple households in Ghana. We employed a transcendental logarithmic cost function to identify the key drivers of quality improvement and production costs.
Key findings and conclusion. Study findings show that GlobalGAP quality improvements require more of all inputs, resulting in higher per hectare productions costs. Among the inputs, capital accounts for the largest share of increases in quality improvement and production costs, and these costs are more responsive to increased use of capital on small farms compared to larger small-scale farms. Fixed improvements account for nearly 80 percent of capital costs. Policy interventions aimed at encouraging smallholder adoption of GlobalGAP standards should therefore focus on lowering the cost of fixed improvements incurred by adopters. It is recommended that ways in which clusters of farmers can share on-farm infrastructure like storerooms for chemicals and equipment should be explored and supported by industry and government stakeholders