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Whole bunch fermentation and the use of grape stems: Effect on phenolic and volatile aroma composition of Vitis vinifera cv. Pinot Noir wine
No full textBackground and Aims: Whole bunch fermentation is widely used in red wine production but research on whole bunch fermentation is limited, especially for cool climate Pinot Noir. Inclusion of whole bunches or grape stems was investigated in Pinot Noir wine production with respect to extraction of phenolic compounds and aroma production.
Methods and Results: Five Pinot Noir wines were microvinified by including grape stems or whole bunches at various levels: destemmed grapes (DS), 100% stems added back (DS100), 30% whole bunches (WB30), 60% whole bunches (WB60) and 100% whole bunches (WB100). The DS100, WB60 and WB100 treatments showed significantly increased tannin and monomeric phenolics but decreased anthocyanin in wines, which would consequently influence the mouthfeel and colour of wine. Volatile compounds responsible for green/vegetative, spicy, woody and medicinal aromas, including 3-isobutyl-2 methoxypyrazine, 3-isopropyl-2-methoxypyrazine, eugenol, ethyl cinnamate and phenol, were significantly increased in DS100, WB60 and WB100 treatments. The WB30 treatment did not show a significant increase of methoxypyrazines in the resultant wine.
Conclusions: By adding stems or a high proportion of whole bunches in fermentation, increased extraction of tannins may improve the mouthfeel and structure of Pinot Noir wine, but the significantly increased concentration of methoxypyrazines could negatively affect wine quality due to the enhanced green characteristics.
Significance of the Study: This study reveals the significant impact of stem inclusion during fermentation on phenolic and aroma compounds in Pinot Noir wine, which provides insights into better use of whole bunches and stems to improve Pinot Noir wine quality
Narrowing urban-rural income gap in China: The role of Targeted Poverty Alleviation program
No full textThe Targeted Poverty Alleviation (TPA) program in China is widely regarded for its influence in eliminating extreme poverty of 70 million rural inhabitants. However, little is known about the extent to which the TPA program narrows the income gap between urban and rural households. Therefore, this study estimates the effect of the TPA program on the urban-rural income gap, measured by the Theil index. A difference-in-difference model with fixed-effects is used to estimate the panel dataset of 279 prefecture-level cities during 2010–2020. The findings show that the TPA program significantly reduced the urban-rural income gap. We obtain robust results using urban-rural income ratio as an income gap measure. Heterogeneous analysis reveals that the income gap reduction effects of the TPA program are largest in the underdeveloped western region, and the effect is smaller for households residing in the central and eastern regions. Effective targeting and a focus on capability building, following regional differences make the program a notable example in reducing poverty and inequality consistent with the Sustainable Development Goals
Is provenance or phylogeny a better predictor of growth and survival of a soil pathogen in leaf litter?
No full textExotic plants have the potential to increase pathogen inoculum that can affect native plants. New Zealand's iconic kauri tree (Agathis australis) is threatened by disease caused by Phytophthora agathidicida, which is most prevalent in fragmented forests that have been invaded by or are adjacent to populations of exotic species. Exotic plants have been introduced intentionally (i.e., plantations and pastures) and unintentionally along the margins of kauri forests, yet it is unclear if invasive species play a role in pathogen spread. To determine the extent to which native and exotic plant litter supports P. agathidicida inoculum, we performed a phylogenetically controlled detached leaf assay. We inoculated 60 native and 44 invasive species’ leaves with three isolates of P. agathidicida collected from two different geographical regions of New Zealand, measured disease symptoms and re-isolated the pathogen from infected leaves. Lesions grew larger and faster on exotic leaves across all three isolates tested. However, pathogen recovery was not necessarily more likely from exotic leaves. In contrast, one of the three isolates grew faster when recovered from native compared with exotic leaves. Phylogeny did not predict disease expression. This data suggests that native and exotic plant litter may be reservoirs for P. agathidicida, but reservoir potential varies among isolates. These results also support key management tools used in New Zealand aimed at reducing pathogen spread by foot traffic in fragmented kauri forests, such as hygiene stations for shoe cleaning at trailheads and boardwalks in sensitive forest areas. Further, these tools may benefit forest management worldwide, as pathogens and exotic, invasive species increase at a global scale
Grasses procure key soil nutrients for clovers
No full textRhizobial nitrogen fixation in legumes provides spillover benefits to neighbouring plants such as pasture grasses. Generally, it is understood to be unidirectional between plant functional groups, providing a benefit from legumes to grasses. We question whether bidirectional complementarity also exists in terms of exploiting the wider soil nutrient pool. We test this hypothesis using soil cores with their component vegetation assemblages sampled from a hill country pasture in South Island, New Zealand. The soil was deficient in key essential elements: P, S, B, Mo and Ni. Facilitation from grasses to clovers was evident; legume–grass mixtures procured more nutrients from the soil than when either species was growing alone. When grasses and clover grow together in unfertilized grassland, more nitrogen is procured by the plant community, and other limiting plant nutrients in the soil are better exploited. Coexistence with grasses is favourable to clovers in terms of soil biogeochemistry
Rural income growth, ethnic differences, and household cooking fuel choice: Evidence from China
No full textThis paper investigates the associations between rural income growth, ethnic differences, and household cooking fuel choice, using the 2016 China Labor-force Dynamics Survey data. We consider the presence of fuel-stacking behavior (using multiple fuels) amongst survey households and categorize cooking fuels into clean fuels, non-clean fuels, and mixed fuels. Data collected from 6,461 rural households are estimated using a multinomial logit model. Findings suggest that relative to households at the lowest income quintile 1, those at the income quintiles 2-5 are more likely to use clean fuels but are less likely to use non-clean fuels for cooking, and the magnitudes of the effects increase across the income quintiles. Compared with the majority Han Chinese households, ethnic minority households are more likely to use mixed fuels but are less likely to use clean fuels for cooking. Only those ethnic minority households at the highest income level (quintile 5) appear to be more likely to use clean cooking fuels
Christchurch, Canterbury region, Aotearoa, New Zealand
No full textProjections of sea level rise (SLR) at a regional level in Aotearoa/New Zealand have only recently begun to be quantified, requiring cautious interpretations when developing planning and design interventions. In the case of Ōtautahi/Christchurch, the risk of flooding increased drastically with a series of earthquakes that took place in 2010 and 2011, affecting urban and natural areas. While the city’s typical strategies have been to retreat urban areas to higher ground, raise floor levels, and construct stop banks, this chapter examines SLR from the perspective of using dynamic landforms to protect tidal habitat areas for four different migratory birds that fly along the East Asian–Australasian Flywa
Does mobile payment adoption affect the level and inequality of food expenditure?
No full textThis study examines the impact of mobile payment adoption on the level and inequality of food expenditure using the 2017 Chinese General Social Survey data. We employ the Gini coefficient to measure food expenditure inequality and use the two-stage predictor substitution approach to address the endogeneity of mobile payment adoption. The results show that mobile payment adoption is associated with lower food expenditure. Specifically, mobile payment adopters spend 2,347 yuan less annually on food than non-adopters. Furthermore, food expenditure inequality is lower among mobile payment adopters than non-adopters. Owning a car, education, and income are positively associated with food expenditure; food expenditure inequality is lower in the more advanced regions of China. The results suggest that mobile payments can play an important role in helping households save considerably on food expenditure, a necessary outlay constituting a significant proportion of the overall spending of Chinese households
Financial accessibility, entrepreneurship, and government initiatives: an investigation of small and medium-sized enterprises in Vietnam : A thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University
No full textSmall and medium-sized enterprises (SMEs) in Vietnam account for 98% of total enterprises, employ about 40% of the labour force and contribute about 40% to Vietnam’s gross domestic product (GDP). Vietnam’s SMEs grew by an annual average of 14.6% from 2007 to 2019, with an associated average SME loan growth of 14.7% from 2012 to 2019. However, the lending rate to Vietnam’s SMEs then gradually declined from 13.5% in 2012 to 7.7% in 2019. A survey by the Central Institute for Economics Management (CIEM) in 2015 revealed that financial constraint is the top challenge facing Vietnam’s SMEs in growing their business. The survey also highlighted that only 25% of surveyed SMEs applied for a bank loan and over 85% had problems obtaining loan approval. The two significant reasons that Vietnamese SMEs confront credit constraints are complicated government regulations and SMEs' capacity to repay the loans. The literature also shows that SME entrepreneurship is significantly correlated with credit constraints and SME performance. This study investigates the determinants of credit constraints and how these constraints facilitate or hinder SME performance in Vietnam. We also consider the mediating roles of SME entrepreneurship and government support in the correlation between credit constraints and SME performance.
We develop a survey questionnaire to collect information from Vietnamese SMEs about financial accessibility, entrepreneurship, government support/constraints, and SME performance. The results show that SME credit constraints are significantly driven by credit demand, perceived credit constraints and SME characteristics (e.g., size, business association membership and corporate social responsibility). We also find that credit-unconstrained SMEs have a higher performance than credit-constrained SMEs. Mediation analysis results confirm the complementary mediating effect of SME entrepreneurship that enhances the positive correlation between credit access and SME performance. Mediation analysis also shows that government support significantly positively affects SME credit access, but there is no strong evidence of the effect of government support on SME performance
Wetting and drainage cycles in two New Zealand soil types: Effects on relative gas diffusivity and N₂O emissions
No full textNitrous oxide (N₂O) is a potent greenhouse gas generated in agricultural soils by microbial processes that vary according to soil redox. Soil oxygen (O₂) supply and demand strongly influence soil redox. Migration of O₂ into the soil primarily occurs via gas diffusion, expressed as relative gas diffusivity (Dp/Do), and is influenced by soil structure (air-filled porosity and tortuosity of pores) and soil water content. Soil N₂O emissions have been shown to increase at low values of Dp/Do but detailed studies examining the relationship between Dp/Do and soil N₂O emissions remain limited, with relatively few soil types examined, and no studies of repeated wetting-drainage cycles. Thus, the objectives of this study were to examine how successive wetting-drainage cycles affected both Dp/Do dynamics and associated N₂O emissions in two New Zealand soils; a pallic silt loam and an allophanic loam, with the latter also having a higher organic matter content. Soil cores, repacked to varying density, were wetted up with ¹⁵N enriched NO₃¯ solution and placed on tension tables where they underwent two consecutive 12-day wetting-drainage cycles from saturation to field capacity (0 to 10 kPa). Over time measurements were made of N₂O, N₂, inorganic-N and soluble carbon, while Dp/Do was modelled using soil physical characteristics. For both soils each wetting-drainage cycle induced N₂O fluxes but with 5-fold lower fluxes in the allophanic soil. Greater aggregation and sand content in the allophanic soil generated higher porosity and Dp/Do values that were almost always greater than recognized anaerobic limits. Thus, wetting-induced N₂O fluxes observed in the allophanic soil during early drainage were concluded to result from anaerobic or hypoxic pathways of N₂O production potentially within the intra-aggregate zone. While wetting-drainage events induce N₂O emissions by altering Dp/Do and the soil aeration status, the draining of soils, especially soils high in organic matter, may enhance O₂ demand generating anaerobic zones conducive to denitrification. Further detailed studies examining the interaction between soil structure and soil organic matter content and their effect on N₂O emissions under wetting-drainage events, with measures of soil O₂, are needed
Electron shuttle potential of biochar promotes dissimilatory nitrate reduction to ammonium in paddy soil
No full textEnhancing dissimilatory nitrate reduction to ammonium (DNRA) is environmentally and agronomically beneficial due to DNRA improving nitrogen (N) retention in soil. However, the rate of DNRA is generally considerably lower than that of denitrification because DNRA requires more electron donors than denitrification. Biochar has been increasingly reported to act as an “electron shuttle” to facilitate electron transfer and to promote redox reactions in soil. Thus, this study aimed to investigate whether and how biochar could enhance the DNRA process in a paddy soil. The results showed that, compared with the no-biochar control, the application of rice straw biochar increased the DNRA rate from 0.2 to 0.7 mg NH₄⁺-N kg⁻¹ dry soil d⁻¹. As well, biochar simultaneously, increased the relative abundance of DNRA functional microbes (nrfA-type microbes) and functional gene (nrfA) expression levels. Biochar's enhancement of DNRA was positively correlated with the biochar properties relevant to electron shuttling (e.g., specific capacitance). In contrast, the application of electron shuttle-weakened biochar (oxidized by H₂O₂) did not increase, or even decreased, the DNRA rate in the paddy soil. These results demonstrate that biochar can act as an electron shuttle to enhance electron availability for DNRA functional microorganisms and consequently promote the DNRA process in paddy soil. Our results indicate that amendment of paddy soil with biochar containing a high-capacity electron shuttle function is beneficial for preserving N by transforming the mobile nitrate anion into the less mobile ammonium cation in paddy soils