19366 research outputs found
Sort by
Supply-demand measurement and spatial allocation of Sponge facilities for Sponge city construction
No full textSponge City Construction (SCC) has been extensively explored for controlling frequent urban waterlogging and non-point source pollution. Assessing the “supply” and “demand” of SCC as a city-wide approach may aid in appropriate areal coverage to achieve optimal performance on flood control based on local priorities and sustainable urban development plans. However, to date, very few studies have examined the potential spatial mismatches in the “supply” and “demand” of SCC. This study presented the development of a framework to explore the supply–demand relationship based on a spatial multi-criteria evaluation of the existing SCC facilities, risk exposure, and socio-economic vulnerability. The feasibility and application of such a framework were successfully demonstrated in a field application in Guangzhou, China. The results indicated that most of the high-density areas in the city centres of Guangzhou were exposed to high risk with strong SCC demands. Furthermore, Liwan and Yuexiu districts exhibited SCC supply deficits, while SCC supply surpluses were observed in other central districts in Guangzhou. The findings of this study provided insight into the development of a generalised and replicable method that could be used to achieve a balance between the “supply” and “demand” of SCC for more participatory, strategic and multifunctional planning of SCC in various urban contexts
Navigating the depths of marine lipids: From extraction efficiency to flavour enhancement
No full textMarine lipids are recognised to have substantial importance in biology and human health. These remarkable lipids, which originate from the rich biodiversity of the oceans, hold a unique status for several reasons. Marine lipids provide long-chain omega-3 fatty acids (n-3 LCPUFAs), specifically eicosapentaenoic acid (EPA, C20:5) and docosahexaenoic acid (DHA, C22:6) (Ahmmed, Ahmmed, et al., 2021; Ahmmed, Carne, et al., 2021; Ahmmed et al., 2022a, 2022b; Ahmmed et al., 2023), that play an important role in health and wellbeing (Zhang et al., 2019), and especially brain health (Ahmmed et al., 2020; Ahmmed et al., 2023; Burri et al., 2012)
Real-time genomics for One Health
No full textThe ongoing degradation of natural systems and other environmental changes has put our society at a crossroad with respect to our future relationship with our planet. While the concept of One Health describes how human health is inextricably linked with environmental health, many of these complex interdependencies are still not well-understood. Here, we describe how the advent of real-time genomic analyses can benefit One Health and how it can enable timely, in-depth ecosystem health assessments. We introduce nanopore sequencing as the only disruptive technology that currently allows for real-time genomic analyses and that is already being used worldwide to improve the accessibility and versatility of genomic sequencing. We showcase real-time genomic studies on zoonotic disease, food security, environmental microbiome, emerging pathogens, and their antimicrobial resistances, and on environmental health itself – from genomic resource creation for wildlife conservation to the monitoring of biodiversity, invasive species, and wildlife trafficking. We stress why equitable access to real-time genomics in the context of One Health will be paramount and discuss related practical, legal, and ethical limitations
Yield and persistence of legume monocultures grown in the Lees Valley, South Island High Country
No full textSix legume monocultures were established in the Lees Valley, North Canterbury (400 m a.s.l.), which has long cold winters. The stony soils have low pH, high aluminium concentration, and low water holding capacity, which can lead to severe summer soil moisture deficits. The aim was to identify legumes that would survive and persist in this environment and, therefore, increase the available nitrogen in the pastoral system. Legume populations of 88±12 seedlings/m² were established and ranged from 45 (sub clover) to 197 seedlings/m² (Caucasian clover). The highest yields were from ‘Pawera’ red clover at 2.5 and 2.9 t DM/ ha in Years 2 and 3, ‘Demand’ white clover produced 1.7 and 2.6 t DM/ha, and ‘Endura’ Caucasian 1.8 and 1.7 t DM/ha. ‘Kaituna’ lucerne yields were low at 0.7 and 1.4 t DM/ha. Caucasian clover was the most persistent legume. A visual assessment in Year 5 found Caucasian was the only legume still dominating its plot (69%) with the lowest area of bare ground (11%). ‘Leura’ subterranean and ‘Bolta’ balansa annual clovers survived for four years but accumulated annual yields were low (50%). While red and white clover provided the highest yields for two years, Caucasian clover was the most persistent species and is therefore a legume recommended for this environment
Lactobacillus buchneri and molasses can alter the physicochemical properties of cassava leaf silage
No full textIn developing countries where feed resources are scarce, cassava leaves can be used as feed for animals. However, the use of cassava leaves is limited mainly because of their high fibre content and overall acceptability by animals. The resolution to this problem is to process the cassava leaves by ensiling and using additives. Therefore, the objective of the study was to determine the effects of including different inclusion levels of molasses and bacteria concentration on the physicochemical properties of cassava leaf silage. Molasses was added at inclusion levels of 0, 3, 5 and 7 g/100g of the chopped cassava leaves, and Lactobacillus buchneri was mixed with chopped cassava leaves at different concentrations of 0, 3.1 × 10⁶ cfu/ml, 3.1 × 10⁸ cfu/ml and 3.1 × 10¹⁰ cfu/ml. The effects of inclusion level of molasses on the colour, smell and texture of cassava leaf silage were significant (P < 0.05). Inclusion of bacteria concentration also influenced the smell of silage (P < 0.05). Effects of the inclusion level of molasses and bacteria concentration resulted in decreased pH, crude protein and crude fibre of silage (P < 0.05). There was a quadratic relationship between Ca and K with inclusion level of molasses in cassava leaf silage (P < 0.05). A positive linear relationship was observed between Mg and molasses inclusion levels in cassava leaf silage (P < 0.05). Using principal component analysis (PCA), molasses had a strong positive correlation with PCA 1, whereas crude fibre, pH and crude protein had a positive correlation with PCA 2. The inclusion level of bacterial concentration was negatively correlated to Ca, CP, P and CF. From the study, the use of molasses and L. buchneri can greatly improve the physicochemical qualities of cassava leaf silage
Plant species identity and plant-induced changes in soil physicochemistry—but not plant phylogeny or functional traits - shape the assembly of the root-associated soil microbiome
No full textThe root-associated soil microbiome contributes immensely to support plant health and performance against abiotic and biotic stressors. Understanding the processes that shape microbial assembly in root-associated soils is of interest in microbial ecology and plant health research. In this study, 37 plant species were grown in the same soil mixture for 10 months, whereupon the root-associated soil microbiome was assessed using amplicon sequencing. From this, the contribution of direct and indirect plant effects on microbial assembly was assessed. Plant species and plant-induced changes in soil physicochemistry were the most significant factors that accounted for bacterial and fungal community variation. Considering that all plants were grown in the same starting soil mixture, our results suggest that plants, in part, shape the assembly of their root-associated soil microbiome via their effects on soil physicochemistry. With the increase in phylogenetic ranking from plant species to class, we observed declines in the degree of community variation attributed to phylogenetic origin. That is, plant-microbe associations were unique to each plant species, but the phylogenetic associations between plant species were not important. We observed a large degree of residual variation (> 65%) not accounted for by any plant-related factors, which may be attributed to random community assembly
Formulation of pasture seed mixtures with emphasis on the effect of nitrogen fertilisation : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
No full textThe aim of this study was to determine the optimal proportions of pasture mixtures and amounts of seed and nitrogen fertiliser (N) to maximize yield and quality. Three monocultures and seven species mixtures, that differed widely in their proportions (0 to 1) of perennial ryegrass, white clover and plantain were sown at 1,000 and 2,000 viable seeds/m2 and with either 0 or 225 kg N/ha/year. Plots were drilled in 2.1 x 6 m plots on 31 March 2017 and measured for four years. The plots were grazed in common by sheep eight times annually (except the first defoliation after sowing when they were cut) and irrigated when required.
Herbage accumulation and its proportions of sown species and weeds were determined at each harvest over four years (2017/2018–2020/2021); nutritive value (metabolisable energy (ME), crude protein (CP) and neutral detergent fibre (NDF)) over three years (2018/2019–2020/2021), and light interception and radiation use efficiency (RUE) over two years (2018/2019–2019/2020).
To quantify the fractional intercepted radiation of pastures, an accurate method of measuring light interception was investigated. Fractional intercepted radiation was measured or predicted using a SunScan plant canopy analyser, GreenSeeker handheld sensor, rising plate meter (RPM), destructive harvests, and the combinations of SunScan and GreenSeeker, and SunScan and RPM. A hybrid method of SunScan and RPM (fractional light interception values ≤0.3 of SunScan were replaced with the predicted values using RPM) was chosen as an accurate method based on the parameters of extinction coefficient, critical LAI, R2 values, standard errors of regression.
Response variables were quantified using diversity-interaction modelling to quantify effects of species ‘identity’ (monoculture performance or average monoculture performance of species in the mixtures) and ‘diversity’ (the excess of mixture performance over that expected from average performance of species in the mixtures).
Seed density did not influence species identity and diversity effects on pasture yield and quality in any year.
The annual total dry matter yields of ryegrass and plantain averaged over four years were 16.8 and 16.6 t DM/ha/year without N fertiliser, and 19.1 and 18.9 t DM/ha/year with N. White clover had the same production (14.9 t DM/ha/year) ± N. Mixtures produced diversity effects (additional dry matter yield). The highest extra dry matter yield (4.32 t DM/ha/year) among binary mixtures was obtained from the ryegrass-white clover mixture at the average of two N treatments. Three-species mixtures needed N to produce higher extra yield than binary mixtures. The extra benefit produced by the equal-proportional mixture of three species with N was 5.20 t DM/ha/year.
The annual weed yield was lowest in perennial ryegrass (1.68 t DM/ha/year) at average N (average of 0 and 225 kg N/ha/year). The weed yield of ryegrass reduced from 2.16 at the –N level to 1.2 t DM/ha/year at the +N level. There was no N effect on weed yields of white clover and plantain. Mixtures reduced weed yield, and the highest amount of weed reduction was found in the even three-species mixtures (3.28 t/ha/year).
Nutritive values were likely to be a function of identity effects and there was no effect of N. At average N, ME was higher in perennial ryegrass (11.0 MJ kg/DM) and white clover (11.0 MJ kg/DM) than in plantain (10.7 MJ kg/DM). CP was higher in white clover (25.7%) than plantain (20.5%) and perennial ryegrass (19.2%). Higher neutral detergent fibre (NDF) was found in perennial ryegrass (47.8%) than plantain (36.3%) and white clover (35.0%).
After four years, an equi-proportional mixture of perennial ryegrass and white clover, based on seed count and equivalent to 12 kg PR and 7 kg WC (19 kg total coated seed)/ha at the low seed density (1000 seeds/m2), produced an optimal balance of increased total yield (20.6 t DM/ha/year), weed suppression (3% of total yield), ME (11 MJ/kg DM), CP (21.7%) and NDF (44%) at the –N level. The optimal mixture at the +N level was the three-species mixture with the proportion of 0.4 PR: 0.3 WC: 0.3 P equivalent to 9.60 kg PR, 4.20 kg WC, and 6.0 kg P (19.8 kg total coated seeds/ha) at the low seed density. It produced 23.0 t DM/ha/year with no weed, 10.8 MJ ME kg/DM, 19.5% CP, and 46.1% NDF. The equi-proportional seed mixture of perennial ryegrass and white clover changed to a mixture of 71% ryegrass, 26% white clover, and 3% weed as the actual proportions in the sward averaged over four years, yielding 20 t DM/ha/year. At the +N level, all three species mixtures, which changed to ryegrass-dominant mixtures in a four-year period, remained the highest-yielding mixtures, producing 20.8–22.4 t DM/ha/year.
Differences in dry matter yield among mixtures were fully explained by the combined effect of light interception and radiation use efficiency (RUE). The optimal mixtures ±N that maximised intercepted light and RUE simultaneously were the same mixtures that produced maximum dry matter yield. They provided 188 and 170 MJ/m2/year more intercepted photosynthetically active radiation (PAR) and 0.23 g DM/MJ PAR more RUE.
This study provided the two optimal seed mixtures for ±N level that maximised total dry matter yield with high quality and minimised weed yield under irrigated conditions. The dry matter yield differences among monocultures and mixtures were explained by the accumulated intercepted PAR and RUE. Moreover, there was an observation that accumulated intercepted PAR and RUE values changed depending on the methods used to measure light interception
Minutes of the inaugural 25 October 2022 meeting of International Committee on Systematics of Prokaryotes (ICSP) Subcommittees on Taxonomy representatives: Challenges, trends, and perspectives for microbial taxonomists
No full textA special online meeting to discuss contemporaneous issues facing ICSP Subcommittees on Taxonomy was convened for Chairs and/or Secretaries of these groups by the current Secretary for Subcommittees, S.L.W. On. In attendance were representatives from 13 of the 16 Subcommittees currently active: namely those covering aerobic Bacteroidota (J. Bowman), Aeromonadaceae, Vibrionaceae and related organisms (F. Thompson), Bifidobacterium, Lactobacillus and related organisms (P. Mattarelli), Campylobacter and related bacteria (S.L.W. On), Chlamydiae (N. Borel), Halobacteria (A. Oren), Halomonadaceae (D.R. Arahal), Methanogenic Archaea (O.P. Sharma), Micrococcinaceae (K.-I. Suzuki), Myxococcota (R.L. Hahnke, R. Garcia), Pasteurellaceae (H. Christensen), Phototrophic bacteria (A. Wilmotte), Rhizobia and Agrobacteria (J.P.W. Young). The Chair of the ICSP, I.C. Sutcliffe, was also in attendance. The meeting was convened at 8 pm (NZT) on 25 October 2022
Using archival material in tourism, hospitality and leisure studies: Beauty and the beast
No full textThe aim of this chapter is to emphasize the importance of archival material and how, despite its secondary nature, it is capable of providing first-hand information for researchers. By providing a variety of examples from tourism, hospitality and leisure, this chapter demonstrates how this underused data can be a valuable resource for these areas of study. In order to illustrate how to use archival material as data, a step-by-step process to analyzing archival photographs is provided. The chapter discusses the challenges and ethical considerations associated with using archival material while also providing suggestions for the use of this data source in future studies
Microwave field measurement of New Zealand alpine snow wetness
No full textWe present a method of measuring the complex permittivity of alpine snow in the microwave S-band (2.1-4 GHz) using the waveguide method. This method was field trialed in the Southern Alps in New Zealand, where six snow samples of varying melt conditions were measured and their complex permittivity calculated. Combined with snow density data, we estimated the volumetric liquid water content (i.e. snow wetness) of the snow samples. This data allows us to assess the viability of aerial snow depth surveys with the ultra-wideband radar