New Zealand forests have been reduced and degraded by gross removal, logging, and the effects of mammals introduced by Polynesian and European settlers. These changes increase the value of the remaining forests, so information on the effects of these disturbances will be useful to inform the management of forest protection. Integrated measurements of C and N cycling within forests can be obtained using foliar stable isotope ratios, which may detect differences between forests resulting from natural or anthropogenic disturbances. This thesis characterises the stable isotopic composition distribution and likely drivers of isotopic variation of vegetation in several central South Island forests, and provides a baseline for future ecological New Zealand studies of present and pre-human vegetation. The largest detected stable isotope variation in modern leaf material was that of δ15N values between the eastern and western podocarp-broadleaf forests. This variation was probably controlled by the lower soil N availability associated with the high rainfall of western forests causing low δ15N values (-8.5 ± 3.5 ‰) relative to an eastern forest (+1.6 ± 1.3 ‰) and global temperate forests (average -2.8 ± 2.0 ‰ (Martinelli et al. 1999)). The significant but slightly higher mean δ15N (0.6 ‰) of a historically selectively logged forest (Saltwater Forest) in comparison to the mean in an unlogged forest (Okarito Forest), on the West Coast, could be attributed to either alteration to N cycling from logging, site differences in topography, or local soil N differences between the forests. Although δ13C showed no significant geographical variation, the well-described ‘canopy effect’ was observed in all modern forests, manifested as a positive covariation between δ13C and vegetation height. Similarly, large taxon-specific differences were observed between δ15N and δ13C values in both modern and fossil leaves. Well-preserved fossil leaves, from sediments c. 4500 years B.P in Pyramid Valley, North Canterbury, had higher δ13C (4.2 ‰) and δ15N (2.5 ‰) values than modern vegetation from Riccarton Bush, Christchurch. The difference between ecosystems spanning several millennia probably reflects ecosystem-scale changes in C and N cycling within New Zealand forests following human arrival, particularly from the degradation caused by invasive animals.

The work presented in this dissertation explores the nature of agro-pastoral strategies developed by Neolithic farmers as a way to understand how early food production was inter-twined with environmental and socio-economic opportunities and constraints. Towards this end, a multi-isotope approach is used to address questions of scale and intensity of crop cultivation and animal management at the archaeological sites of Kouphovouno, southern Greece, Makriyalos, northern Greece, and Çatalhöyük, south-central Turkey. Measurements of stable carbon, nitrogen, oxygen and strontium isotope values of carbonized plant remains, human and animal bone collagen and animal tooth enamel are used to examine the similarities and differences in the types of treatments that individual species of plants and animals received during the agricultural cycle at the distinct locations. The results show that farmers at the three sites developed variable methods for exploiting the arable and pastoral landscape and catering to their economic and culinary needs. The discussion considers the implications of these findings to our understanding of the complexity and adaptability of early farming systems.

Doctor of Philosophy / Department of Entomology / Alberto B. Broce / Ludek Zurek / Stable flies, Stomoxys calcitrans (L.), are a serious pest to beef cattle in confined animal feeding operations (CAFOs) by causing economic losses in the form of reduced feed intake and feed efficiency, resulting in reduced weight gain. Integration of sanitation, parasitoids, and residual insecticides offers a much-needed reduction of this pest's impact on CAFOs. In the past two decades, stable flies have become the most important pest of pastured cattle. Further impact that stable flies have on cattle is when cattle seek protection from stable flies by standing in water, which results in water pollution with fecal matter, in addition to reduced foraging time. Sites of winter feeding of round hay bales have demonstrated to be important habitats for stable fly development during spring/summer. Cattle feeding on round bales can waste as much as 40% of the total amount of hay when fed in conventional ring feeders. Hay wastage is largely a function of the type of feeding method and the amount of agonistic behavior of the cattle. Feeding methods range from rolling hay directly onto the ground to the use of various types of feeders. Since traditional control methods utilized in CAFOs against stable flies have not been evaluated in pastures, producers rely heavily on organic insecticides in efforts to control this pest. At this time, there are no effective control methods available for stable fly management on pastured cattle. This research examined different management strategies that could minimize or eliminate stable fly larval habitats by reducing the amount of hay wasted being mixed with manure. In addition, different hay and manure mixtures were compared to characterize the larval habitat at these hay-feeding sites. Finally, the efficacy of boric acid, Metarhizium anisopliae, and tetrachlorvinphos in controlling the development of stable flies in hay substrates was evaluated.

Individual niche variation is increasingly being demonstrated in animal populations in a wide variety of species and taxa. Niche variation among individuals has important implications for the ecology, evolution and management of animal populations and is a subject of increasing interest. However, despite its widespread occurrence the causes and consequences of individual niche variation remain poorly understood. In this thesis I use the European badger (Meles meles), a well studied species of high ecological interest, as a model system to investigate individual niche variation. In order to achieve this I combine information on individual foraging niches derived via stable isotope analysis (SIA) of badger vibrissae with detailed life history and ecological data from a long-term study population to investigate the incidence, cause and consequence of individual niche variation within badger social groups. First I use the biomarker Rhodamine B to investigate vibrissae growth rates and patterns in badgers and demonstrate that the isotopic composition of a single vibrissa likely reflects diet over several months (Chapter 2). Next I explore the use of SIA as a tool to investigate badger diet, by comparing isotopic patterns to seasonal changes in diet measured using faecal analysis (Chapter 3). My results provide validation that SIA is powerful tool for investigating foraging variation in this species, and suggest that within badger populations substantial dietary variation may occur among individuals. Further investigation of isotopic variation Indicates that individuals within social groups differ markedly and consistently in their isotopic signature, independent of age and sex effects and that in some instances these differences are remarkably consistent across year (Chapter 4).This suggesting long term individual specialisation (Chapter 4). I find that the degree of this individual specialisation, and the relationship between specialisation and body condition is influenced by competition for resources (Chapter 5). Social groups with higher levels of competition exhibit greater specialisation and specialised individuals within these highly competitive environments are in better condition. Finally, I discuss the implications of these results for individual niche variation, for the application of SIA to study this behaviour and for badger ecology generally (Chapter 6). I also outline future directions for further research.

Sublimation experiments have been carried out to determine the effect of the mineral dust content of porous ices on the isotopic composition of the sublimate gas over medium (days to weeks) timescales. Whenever mineral dust of any kind was present, the D/H ratio of the sublimated gas was seen to decrease with time from the bulk ratio. Fractionations of up to 2.5 were observed for dust mixing ratios of 9 wt% and higher of JSC MARS-1 regolith simulant 1-10 mum crushed and sieved fraction. These favored the presence of the light isotope, H2O, in the gas phase. The more dust was added to the mixture, the more pronounced was this effect. Theoretical modeling of gas migration within the porous samples and adsorption on the excavated dust grains was undertaken to explain the results. Adsorption onto the dust grains is able to explain the low D/H ratios in the sublimate gas if adsorption favors retention of HDO over H2O. This leads to significant isotopic enrichment of HDO on the dust over time and depletion in the amount of HDO escaping the system as sublimate gas. This effect is significant for planetary bodies on which water moves mainly through the gas phase and a significant surface reservoir of dust may be found, such as on Comets and Mars. For each of these, inferences about the bulk water D/H ratio as inferred from gas phase measurements needs to be reassessed in light of the volatile cycling history of each body.PACS CODES:98.80.Ft Isotopes, abundances and evolution (astronomy)], 64.70.Hz Sublimation], 68.43.-h Adsorption at solid surfaces]

The Eurasian woodcock Scolopax rusticola (hereon woodcock) is a wader adapted to woodland and farmland habitats. It is an important quarry species, widely hunted across Europe, but owing to its cryptic plumage and elusive nature, there exists only poor information concerning its natural history. As such, the conservation status of the woodcock remains uncertain. One area that is particularly lacking is knowledge of its ecology outside the breeding season. Generally, avian ecological studies have focused on breeding season events due to the importance of reproductive success in determining fitness. However, it is now apparent that the non-breeding season represents an equally important period of the annual cycle. For example, recent studies have shown that declines in some migratory bird populations were due to events during the non-breeding season, either during migration, or on the wintering grounds. In Britain, the non-breeding woodcock population comprises both British breeding and non-British breeding birds, yet the origins and relative distribution of these sub-populations is not fully understood. Nor is it known whether ecological differences exist between them. This thesis addresses these two aspects of woodcock biology, using stable isotope and radio-tracking methods. The former was used to assign birds to their likely origins and determine population-specific distributions across Britain. The latter was used, in conjunction with the former, to determine whether ecological differences exist between locally-breeding and non-locally breeding birds residing in Hampshire in winter. A large degree of mixing between birds from different breeding populations was apparent for woodcock residing in Britain over winter. Russia and Fennoscandia comprised the most likely origins of migratory birds and regional differences in distributions were apparent. The highest proportions of birds from Russia were found in Norfolk and Wales, whilst the highest proportions of birds from Fennoscandia were found in Scotland. The presence of non-breeding residents in Cornwall and Ireland also provided strong evidence for the short-distance, south-westerly movements of resident birds, which probably originated from Scotland. Locally, the movements and behaviour of birds were found to vary with age (adult vs. juvenile) and/or predicted migratory status (resident vs. migrant), with adult residents potentially representing the dominant group. Differences in habitat use, commuting flights, home range size and activity patterns were all apparent. As such, these findings might have important consequences for the relative survival rates and breeding success of resident and migrant woodcock. This work has provided new insights into the non-breeding ecology of woodcock in Britain and contributes significantly to European efforts to better understand this bird species. Given the importance of seasonal interactions, an understanding of events throughout the annual cycle is necessary and this can only be achieved through concerted efforts. Indeed, an integrated approach is imperative to develop the conservation plans necessary to ensure the sustainability of the woodcock.

Current software engineering topics such as clone detection and service selection need to improve the capability of detection process and selection process. The clone detection is the process of finding duplicated code through the system for several purposes such as removal of repeated portions as maintenance part of legacy system. Service selection is the process of finding the appropriate web service which meets the consumer’s request. Both problems can be converted into a matching problem. Matching process forms an essential part of software engineering activities. In this research, a well-known mathematical algorithm Stable Marriage Problem (SMP) and its variations are investigated to fulfil the purposes of matching processes in software engineering area. We aim to provide a competitive matching algorithm that can help to detect cloned software accurately and ensure high scalability, precision and recall. We also aim to apply matching algorithm on incoming request and service profile to deal with the web service as a clever independent object so that we can allow the services to accept or decline requests (equal opportunity) rather than the current state of service selection (search-based), in which service lacks of interacting as an independent candidate. In order to meet the above aims, the traditional SMP algorithm has been extended to achieve the cardinality of many-to-many. This adaptation is achieved by defining the selective strategy which is the main engine of the new adaptations. Two adaptations, Dual-Proposed and Dual-Multi-Allocation, have been proposed to both service selection and clone detection process. The proposed approach (SMP-based) shows very competitive results compare to existing software clone approaches, especially in identifying type 3 (copy with further modifications such update, add and delete statements) of cloned software. It performs the detection process with a relatively high precision and recall compare to the CloneDR tool and shows good scalability on a middle sized program. For service selection, the proposed approach has several advantages such as service protection and service quality. The services gain equal opportunity against the incoming requests. Therefore, the intelligent service interaction is achieved, and both stability and satisfaction of the candidates are ensured. This dissertation contributes to several contributions firstly, the new extended SMP algorithm by introducing selective strategy to accommodate many-to-many matching problems, to improve overall features. Secondly, a new SMP-based clone detection approach to detect cloned software accurately and ensures high precision and recall. Ultimately, a new SMPbased service selection approach allows equal opportunity between services and requests. This led to improve service protection and service quality. Case studies are carried out for experiments with the proposed approach, which show that the new adaptations can be applied effectively to clone detection and service selection processes with several features (e.g. accuracy). It can be concluded that the match based approach is feasible and promising in software engineering domain.

This project addressed if decaying macroalgae and leaf detritus play a major role in the detrital pool of a 7th-order karst riverine system. Decay rates, macroinvertebrates colonization patterns, and change in δ13C values of Cladophora, Platanus occidentalis, and a mix of Acer negundo and A. saccharinum were tracked during summer and autumn months for portions of multiple years. Packs of air-dried Cladophora, Acer, and P. occidentalis were placed in mesh bags and put in groups (n=4) in wire baskets. Seven baskets were submerged in riffle (0.5 m) and deeper run (2 m) habitats. Benthic organic matter was collected with each pack to see if there was a correlation with δ13C signatures of decaying macroproducers to help understand what is entering the detrital food web. Summer 2014 Cladophora and Acer were significantly faster to breakdown than Platanus in both habitats. In autumn‒spring 2014‒2015, Cladophora was significantly faster to breakdown than leaves. Isotopic values of Cladophora were not significantly different than leaves in summer 2014 but were significantly more δ13Cdepleted in the autumn‒spring 2014‒2015. There were no significant differences in macroinvertebrate abundance between the macroproducers for either season. Cladophora had significantly lower macroinvertebrate richness in both seasons, lower shredder abundance, but a significantly higher abundance of clingers. The mean δ13C values of benthic detritus were significantly different than all three macroproducers in the summer and significantly different than Cladophora in the run treatment for autumn‒spring. Seasonality had a strong influence on breakdown rates, leading to greater mass loss of all three species in the warm summer months compared to the cooler autumn‒spring months. The low macroinvertebrate richness and shredder abundance on the decaying macroalga suggests Cladophora may not be consumed by macroinvertebrates but used strictly as habitat. The implication of rapid Cladophora decay during warm seasons, plus few colonizing macroinvertebrate taxa, is that the decaying macroalgae may not pass through a decomposer food web before being remineralized as CO2.

Laser Sintering is an Additive Manufacturing technology that uses digital files to construct 3-dimensional parts by depositing and consolidating layers of powdered material. Application of the technology for metal and ceramic powders is common but the focus of this work was on polymer laser sintering. A significant drawback for polymer laser sintering is the limited selection of materials currently available for use compared with more conventional processes such as injection moulding. This constrains the usefulness of the technology for designers and engineers. A primary reason for this is a lack of detailed understanding of the development process for new materials for laser sintering. This PhD investigation examines some of the key attributes and requirements needed for successfully implementing new polymer-based laser sintering materials. A strategic method for characterizing and identifying new polymer materials was created utilizing thermal measurements, practical and analytical methods to quantify sintering rate, and degradation studies. Validation of this work occurred through the successful integration of a new laser sintering material at industrial project partner Burton Snowboards. Thermal degradation as a result of the laser sintering process was studied in detail and resulted in the creation of a proposed new parameter: Stable Sintering Region (SSR). The term acknowledges and defines the region above the melting point that is the minimum requirement for sintering to occur and an upper limit beyond which polymer deterioration impedes on mechanical properties. A quantitative approach to define the SSR was developed and explored with three different laser sintering materials, two of which were flexible elastomers. The ability to specifically interpret laser sintering process parameters from thermal degradation characterization was created and used to explore the effects of high energy input on tensile properties and molecular weight. The results of these tests showed the potential to identify an Optimum Sintering Range based on maximizing mechanical properties through the control of energy input and molecular weight. This thesis makes a significant contribution to the knowledge and understanding of polymer laser sintering, especially in the context of materials development. Novel concepts such as the Stable Sintering Region were developed using a theoretical approach and practical measurements and were also thoroughly explored for verification. Additionally, a new method to use a powder characterization technique to predict the actual machine parameters of a material in the laser sintering process was quantified. This has several implications for testing new materials for laser sintering and efficiently identifying appropriate processing conditions.

The Saskatchewan River Delta (SRD) in central Canada, North America’s largest inland delta, is an important spring and fall stopover site for waterfowl with thousands flocking there annually to stage. However there is very little information on their origins prior to arrival and their feeding ecology while in the Delta. To date, band recoveries are largely from birds banded south of the SRD, mostly due to limited banding activity in productive waterfowl habitats to the north such as the Peace-Athabasca Delta and the broader boreal forest. There is also very little information on the importance of the SRD as an overall recruitment area for the North American waterfowl population. No studies have used stable isotopes to infer the origins and diets of these birds. I first used stable isotopes of hydrogen (2H) and sulfur (34S) to infer migratory origins and specifically evaluate the contribution of local and non-local birds to the staging population in the SRD during fall migration. Based on 2H, I found that few birds (34%) originated in the SRD despite its known role as breeding habitat; instead, most birds (56%) were migrants from the north of the SRD and a small fraction (10%) came from south of the SRD. Stable sulfur isotope data proved a useful tool in further delineation of birds into prairie and forest regions, respectively. Secondly, I used stable carbon (13C) and nitrogen (15N) isotopes and mercury concentrations in liver tissue ([Hg]) to trace nutrient sources of these waterfowl using the SRD prior to fall migration, and tested for differences in diets among species, sexes and age groups within species. I demonstrated the importance of macrophytes as a source of food, particularly among the American Widgeon and Northern Pintail (70% of the diet). However, there was some level of partitioning of resources at the species level, as Blue-winged Teal and Green-winged Teal used invertebrate sources, as did a distinct group of Mallards. This is likely a result of birds minimizing competition for resources during the short staging period in the SRD when waterfowl densities are high. Finally, I found that 15N values in liver, a known indicator of trophic position, can be confounded by variation in basal sources; hence, there is the need to use other isotopes or tracers such as [Hg] for verification. Overall, my results suggest an important role for northern ecosystems in central Canada in contributing to the waterfowl breeding population in the Central Flyway, and a key role for the SRD in providing fuel for waterfowl during fall migration. .