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An investigation of systematic camera trap monitoring for kiwi (Apteryx spp.) : A thesis submitted in partial fulfillment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
No full textIntroduction: Kiwi (Apteryx spp.) are one of New Zealand’s national taonga/taoka (treasures) that are
our responsibility and privilege to protect. To inform protective management, we need to monitor
kiwi population responses to management, for which a non-invasive method that can detect all age
classes has been lacking. Camera traps are non-invasive monitoring devices, which are increasingly
used with recently developed analyses to monitor cryptic terrestrial species around the world. To
apply these methods to kiwi, standardized methods need to be developed and benchmarked against
existing methods.
Aims: The aims of this study were to 1) summarise previous monitoring work on kiwi to develop a
draft systematic camera trap monitoring method for kiwi, 2) determine optimal site selection and
camera trap set-up, 3) determine optimal survey length and camera trap spacing for use with spatial
presence-absence (SPA) analysis and identify whether realistic population estimates are obtained, 4)
compare camera traps with a current noninvasive method using acoustic recorders to determine if
they give realistic and comparable estimates when used with SPA, 5) compare camera traps with dog
survey and an observer listening survey to assess kiwi population health, 6) trial alternative analyses
for use with camera traps in high density sites, 7) investigate stereo cameras for their potential to
add value to camera trap surveys.
Materials and methods: We summarised the current literature on monitoring kiwi and the use of
camera trap surveys. We deployed 34 camera traps over six seasons in Orokonui Ecosanctuary. We
deployed 29 acoustic recorders and carried out detector dog surveys to compare the number of
juveniles detected. We deployed 17 camera traps in Rotokare Scenic Reserve and 18 camera traps in
the Cape Sanctuary to examine their effectiveness in high kiwi density areas. We constructed a
stereo camera by chaining two off-the-shelf trail cameras together to trigger from one PIR sensor
and briefly trialled the stereo camera at Orokonui.
Results: Cameras were able to detect kiwi of all age groups and to provide credible population
densities and trends. Kiwi detections can be maximised by using a detector dog team to select
camera sites and through camera orientation. Comparable population estimates were obtained
using spatial presence-absence (SPA) analysis with an optimal survey length of four months, during
peak incubation, and optimal camera spacing of 350 m. Cameras and acoustic recorders gave
comparable population estimates using SPA. Estimates were realistic based on matrix population
model projection. Camera traps and detector dog surveys found a similar number of juvenile kiwi.
Estimates obtained using Royle-Nichols analysis likely underestimated population size but correctly
indicated population trend direction and magnitude, while the index-manipuation-index method did
not give a biologically possible estimate of population density. The stereo camera method using two
trail cameras was capable of giving surprisingly accurate bill measurements, but further work in
necessary to achieve repeatability.
Discussion and conclusions: Systematic camera trapping is capable of monitoring the whole kiwi
population, including female and young kiwi that are usually under-recorded by other methods.
Systematic camera trapping paired with spatial presence-absence analysis performed well in a low
density population. Camera monitoring shows much promise as another useful noninvasive tool in
the kiwi monitoring toolbox
White clover: A key ingredient of pasture mixes under a 190 kg N/ha/year cap
No full text• White clover is a key ingredient of dairy pastures.
• What is the best pasture mix under 190 kg N/ha/y?
• Effects of mixing species and applying N.
• Series of mixture trials at Lincoln University
Does access to credit really increase mechanization service expenditure? Insights from formal and informal credit perspectives
No full textThis study estimates the effects of access to credit on mechanization service expenditure, utilizing the 2020 China Rural Revitalization Survey data. We distinguish between formal and informal credit access and employ a conditional mixed process (CMP) model to address selection bias issues. The results reveal that access to credit significantly increases mechanization service expenditure by 386 yuan/mu, and the impact is larger on farmers cultivating small-sized farms and those residing in the less developed western region. Access to formal and informal credit affects mechanization service expenditure differently. Specifically, accessing credit from formal sources (e.g., banks) significantly increases mechanization service expenditure by 261 yuan/mu; accessing credit from informal sources (e.g., friends and relatives) significantly decreases the same by 44 yuan/mu. These results are further verified by estimating the effects of loan amounts on mechanization service expenditure. Our findings highlight the importance of improving farmers' access to formal credit in promoting agricultural mechanization
Nitrification regulation by a new organic compost in ultisols of a flue-cured tobacco plantation
No full textNitrate nitrogen (nitrate-N) is crucial for the development of tobacco quality. However, how to enhancing soil nitrification in tobacco plantation is still an immediate concern that requires attention. This study aimed to examine the impact of mixed organic manure on soil nitrification in tobacco cultivation regions. We selected an Ultisols field, which was planted with tobacco from Yunnan province, to explore the impact of adding various organic manures (F1-F6: regular organic manures, F7: mixed organic compost which was derived from crop residues), on soil gross N mineralization and nitrification. This study was conducted through a 75-day indoor leaching experiment, with constant temperature (25°C) and humidity (65% of field water capacity). The results showed that F4 significantly (p < .05) enhanced soil N mineralization, and had the highest mineralized-N and potentially releasable mineralized-N (N₀) due to its highest organic carbon (OC) and total-N, which amounted to 422 mg kg¯¹ and 705.7 mg kg¯¹ , respectively. F7 exhibited a significant increase (p < .05) in the rate of soil N mineralization, with the highest first-order mineralization rate constant (k1) of 0.090 d¯¹. Moreover, it displayed a substantial increase (p < .05) in nitrate-N content and potentially releasable nitrate-N (Np), measuring 41.5 mg kg¯¹ and 41.3 mg kg¯¹, respectively. Furthermore, F7 exhibited the highest first-order nitrification rate constant (k2) of 0.076 d¯¹ . It also demonstrated a considerably higher net nitrate-N/mineralized-N ratio of 33.5%, which was significantly (p < .05) greater than that of F1-F6 (nitrate-N/mineralized-N ratio: −7.06 to 1.86%). At day 15 and day 45, F7 exhibited the highest nitrate-N concentration and nitrate-N/mineralized-N ratio (28.1 mg kg¯¹ and 49.7%) in comparison to F1-F6, which had lower nitrate-N concentrations (ranging from 0.4 to 6.9 mg kg¯¹ ) and nitrate-N/mineralized-N ratios (ranging from 0.4 to 11.9%). These results indicate that the addition of mixed organic compost significantly enhances soil nitrification compared to regular organic manures. Therefore, it suggests that incorporating mixed organic compost improves soil nitrification in Ultisols
A new framework: Non-Western perspectives on international volunteering
No full textInternational volunteering has typically been conceived as a Western sociocultural phenomenon. Within this paper, we aim to apply a non-Western lens to the development of a conceptual framework, through which to consider an alternative perspective on international volunteering. We highlight how, increasingly, non-Western countries are a place that not only hosts international volunteers but also sends volunteers abroad. Using the notions of solidarity, respect and equality, we illustrate the complexities and nuances of what non-Western international volunteering involves. This paper serves as a point of departure for a deeper assessment of the conceptualization of international volunteering from non-Western perspectives that recognize these will be different from Western perspectives, even in an era of globalization partially driven by international volunteering
Urban heat mitigation strategies
No full textUrban heat has been detected in many cities worldwide and has negatively impacted the urban environment and human well-being. Many strategies have been developed to mitigate urban heat, collectively called urban heat mitigation strategies (UHMSs). This study reviewed the four types of passive UHMSs (i.e., greenery, cool materials, evaporation techniques, and shading devices) from an implementation perspective to support urban heat mitigation. The definitions, mitigation performance, planning and design variables, and cost-benefits of these UHMSs are elaborated from three categories, according to the place of application: private realm, public realm, and combinations. The results show that green infrastructures have high performance in cooling and energy saving in private and public realms, and their effectivenesses are affected by many factors, such as vegetation species. For cool materials, reflective materials generally have higher cooling potentials and lower costs than heat storage materials and heat harvesting materials. The predominant planning and design variables for cooling effectiveness are the colour and construction materials, and coating materials. The evaporation techniques can reduce ambient temperature significantly due to the high cooling potential of latent heat. The main variables include water flow rate, water particle size, area and shape of water bodies etc. To achieve optimal cooling performance, it is required to properly define the surface temperature of the evaporative cooling pads for evaporative cooling towers and shading structures and slat angles for shading. Also, UHMS combinations can have higher mitigation performance than a single one. All these findings help decision-makers better understand the implementation of UHMS in detail, supporting the proper selection and application of strategies for urban heat mitigation
Impact of mobile payment adoption on household expenditures and subjective well-being : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Commerce and Management at Lincoln University
No full textIn recent years, mobile payment has gradually become increasingly popular worldwide. Especially in China, mobile payments are ubiquitous and gradually replacing traditional cash payments. This thesis estimates the effects of mobile payment adoption on household expenditures and subjective well-being. It considersfour categories of household expenditures (clothes, durable goods, consumer goods, and cultural and leisure activities) and four indicators (life satisfaction, contentment, income satisfaction, and depression) of subjective well-being. This thesis uses the Augmented Inverse Probability Weighting estimator to analyse the 2017 Chinese General Social Survey data while accounting for the selection bias inherent in mobile payment adoption. The empirical results show that people’s decisions to adopt mobile payments are positively associated with their educational level, car ownership, social interaction, Internet penetration rate, and residential location. Mobile payment adoption significantly increases household expenditures on consumer goods and cultural and leisure activities but not on clothes and durable goods. Moreover, mobile payment adoption significantly decreases contentment while increasing depression. This thesis also finds that mobile payment adoption significantly decreases urban people’s contentment but significantly increases urban people’s depression. Disaggregated analyses show that mobile payment adoption increases spending on consumer goods but decreases contentment for urban households; increases spending on consumer goods and depression for rural households; increases spending on consumer goods; decreases contentment and income satisfaction for male respondents; and increases spending on clothing, cultural, and leisure activities, and depression for female respondents. Therefore, the government should create products and services to extend the benefits of mobile payments to all segments of Chinese society. At the same time, it should help consumers avoid the debt incurredthrough educational programs and advertising
Assessing and optimizing the hydrological performance of Grey-Green infrastructure systems in response to climate change and non-stationary time series
No full textClimate change has led to the increased intensity and frequency of extreme meteorological events, threatening the drainage capacity in urban catchments and densely built-up cities. To alleviate urban flooding disasters, strategies coupled with green and grey infrastructure have been proposed to support urban stormwater management. However, most strategies rely largely on diachronic rainfall data and ignore long-term climate change impacts. This study described a novel framework to assess and to identify the optimal solution in response to uncertainties following climate change. The assessment framework consists of three components: (1) assess and process climate data to generate long-term time series of meteorological parameters under different climate conditions; (2) optimise the design of Grey-Green infrastructure systems to establish the optimal design solutions; and (3) perform a multi-criteria assessment of economic and hydrological performance to support decision-making. A case study in Guangzhou, China was carried out to demonstrate the usability and application processes of the framework. The results of the case study illustrated that the optimised Grey-Green infrastructure could save life cycle costs and reduce total outflow (56–66%), peak flow (22–85%), and TSS (more than 60%) compared to the fully centralised grey infrastructure system, indicating its high superior in economic competitiveness and hydrological performance under climate uncertainties. In terms of spatial configuration, the contribution of green infrastructure appeared not as critical as the adoption of decentralisation of the drainage networks. Furthermore, under extreme drought scenarios, the decentralised infrastructure system exhibited an exceptionally high degree of removal performance for non-point source pollutants
Comparative genome identification of accessory genes associated with strong biofilm formation in Vibrio parahaemolyticus
No full textVibrio parahaemolyticus biofilms on the seafood processing plant surfaces are a potential source of seafood contamination and subsequent food poisoning. Strains differ in their ability to form biofilm, but little is known about the genetic characteristics responsible for biofilm development. In this study, pangenome and comparative genome analysis of V. parahaemolyticus strains reveals genetic attributes and gene repertoire that contribute to robust biofilm formation. The study identified 136 accessory genes that were exclusively present in strong biofilm forming strains and these were functionally assigned to the Gene Ontology (GO) pathways of cellulose biosynthesis, rhamnose metabolic and catabolic processes, UDP-glucose processes and O antigen biosynthesis (p < 0.05). Strategies of CRISPR-Cas defence and MSHA pilus-led attachment were implicated via Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation. Higher levels of horizontal gene transfer (HGT) were inferred to confer more putatively novel properties on biofilm-forming V. parahaemolyticus. Furthermore, cellulose biosynthesis, a neglected potential virulence factor, was identified as being acquired from within the order Vibrionales. The cellulose synthase operons in V. parahaemolyticus were examined for their prevalence (22/138, 15.94 %) and were found to consist of the genes bcsG, bcsE, bcsQ, bcsA, bcsB, bcsZ, bcsC. This study provides insights into robust biofilm formation of V. parahaemolyticus at the genomic level and facilitates: identification of key attributes for robust biofilm formation, elucidation of biofilm formation mechanisms and development of potential targets for novel control strategies of persistent V. parahaemolyticus
Predicting yield of irrigated red clover (Trifolium pratense L.) pastures in response to temperature
No full textTwo datasets from red clover monoculture pastures grown in Lincoln, New Zealand, were analysed to generate coefficients to predict red clover yield. The mean annual production of established red clover was 17.0±0.48 t DM/ha, with a maximum mean growth rate of 125±9.36 kg DM/ha/day (spring Year 2). In the establishment year irrigated red clover grew at a constant rate of 7.30±0.14 kg DM/ha/°Cd (Tb = 3 °C) throughout the year. In contrast, there was a split-line linear response in Years 2 and 3, which differed between years and decreased after the second week of January. Specifically, the growth rate in Phase 1 was 7.70±0.38 kg DM/ha/°Cd in Year 2, which was 16% higher than the 6.60±0.28 kg DM/ha/oCd in Year 3. The difference probably reflected increased competition from weed grasses as red clover content declined from >95% to ~75% of total annual yield. After January, red clover grew at 3.05±0.35 kg DM/ha/°Cd, in both years. This lower rate occurred in the mid-January-July period, and probably reflected a change in partitioning of assimilate to red clover roots in response to a decreasing photoperiod. The coefficients reported here for red clover need to be validated from other datasets. However, they provide easily transferable coefficients that can be used to estimate red clover yield under non-limiting conditions for other locations. These could be integrated into feed budgeting software to assist on-farm decision making