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No. of bitstreams: 1 AnyellePRE_DISSERT.pdf: 3332574 bytes, checksum: 6eba66f5232c1024161e4faadd9f882f (MD5) Previous issue date: 2017-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The increasing degradation of natural wetlands has led many shorebirds populations to use alternative or complementary habitats. The artificial salines are one of the most common alternative habitats used by shorebird to feed and rest in coastal areas. The aim of this study was to investigate the richness, composition, habitat use and seasonal variation of shorebirds species associated with the artificial salines of the Apodi-Mossoró Estuary, Brazilian semiarid. Between August 2012 and July 2016, fortnightly shorebirds Charadriiformes censuses were conducted (2 h duration) in an area of 145 ha of saline from this Estuary (04°57’S; 37°08’O), in periods of high and low tide. A cumulative total of 28,868 records of individuals of 19 species Charadriiformes were obtained during 192 censuses. The number of records of shorebirds per census in the summer (2nd fortnight of August to the first fortnight of March: 167.9 ± 16.9 records, mean ± SE, N = 112 censuses) was similar to that sighted in the winter (2nd fortnight of March to the 1st fortnight of August: 125.7 ± 11.4, N = 80) (U = 4221; p = 0.495). In the summer period, the number of shorebirds records per census did not vary between periods of high tide and low tide (U = 1280; p = 0.094). On the other hand, in the winter, the number of shorebird records at high tide was higher than at low tide (U = 501.5; p = 0.004). Comparing the use of microhabitats over the studied saline area, shorebirds were more frequent in the evaporation ponds (85% of total records), and less frequent in pumping (9%) and crystallization (6%) ponds. There was a significant difference in the number of records of individuals/ha (density), with the highest density of individuals per census in the evaporation ponds (H = 246; p < 0.0001). The evaporation and pumping ponds were used mainly for foraging (respectively 79% and 76% of the records by microhabitat) and the crystallization pond for resting (75%). Our results shows that the Apodi-Mossoró Estuary may be recognized as an important area for the conservation of migratory and resident Charadriiformes populations in the South America. The use of artificial salines of this Estuary by shorebirds as alternative habitats for feeding and resting makes important to implement a continuous environmental monitoring program in the salines in order to ensure the maintenance of species-specific ecological requirements and to avoid chemical contamination of these animals / A crescente degradação de áreas úmidas naturais tem levado muitas populações de aves limícolas a buscarem habitats alternativos ou complementares, sendo as salinas artificiais um dos locais mais utilizados por estes animais para alimentação e descanso. O objetivo deste estudo foi investigar a riqueza, a composição, o uso do habitat e a variação sazonal de espécies de aves limícolas associadas às salinas artificiais do Estuário Apodi-Mossoró, semiárido brasileiro. Entre agosto de 2012 e julho de 2016, foram realizados quinzenalmente censos (2 h duração) de aves limícolas Charadriiformes em uma área de 145 ha de salina deste Estuário (04°57’S; 37°08’O), em períodos de maré alta e baixa. Um total acumulado de 28.868 registros de indivíduos de 19 espécies Charadriiformes foram obtidos em 192 censos. O número de registros de aves limícolas por censo no verão (2ª quinzena de agosto a 1ª quinzena de março: 167,9 ± 16,9 registros, média ± EP, N = 112 censos) foi semelhante ao registrado no inverno (2ª quinzena de março a 1ª quinzena de agosto: 125,7 ± 11,4, N = 80) (U = 4221; p = 0,495). No período do verão, o número de registros de aves limícolas por censo não variou entre períodos de maré alta e de maré baixa (U = 1280; p = 0,094). Por outro lado, no inverno, o número de registros em maré alta foi maior que em maré baixa (U = 501,5; p = 0,004). Em comparação ao uso de microhabitats na salina, as aves limícolas foram mais frequentes nos tanques de evaporação (85% do total de registros), e menos frequentes nos tanques de bombeamento (9%) e de cristalização (6%). Houve diferença significativa no número de registros de indivíduos/ha (densidade), com a maior densidade de indivíduos por censo nos microhabitats de evaporação (H = 246; p < 0,0001). Os tanques de evaporação e bombeamento foram utilizados principalmente para o forrageamento (respectivamente, 79% e 76% dos registros em cada um dos tipos de microhabitat) e os de cristalização para o descanso (75%). A partir destes resultados, o Estuário Apodi-Mossoró pode ser reconhecido como uma relevante área para a conservação de populações de Charadriiformes migratórias e residentes na América do Sul. O uso das salinas deste Estuário como habitats alternativos para alimentação e descanso por aves limícolas implica na necessidade de implementação de um programa de monitoramento ambiental continuado nas salinas, a fim de garantir a manutenção dos requerimentos ecológicos espécie-específicos e a não contaminação química destes animais / 2017-05-05

Stevia or Stevia rebaudiana Bertoni are two of the numerous names of this subtropical plant with a sweetening power as much as 300 times higher than in case of sucrose. Stevia is a plant with a very interesting, but up to this date not very utilised potential. The fields of its application, processing, cultivation and wintering options have not been explored very extensively, and therefore I have decided to elaborate this topic related to the impact of the environmental conditions for growing of Stevia rebaudiana. The resources for the text of the diploma thesis were formed by available specialised publications and the Internet. The first part of the thesis represents a brief overview of the whole issue concerning the topic of Stevia rebaudiana. The objectives, hypotheses and methodology of the conducted research, including the findings based on the plant growing as well, and the evaluation of the experiment results have been included in the second part. The purpose of the thesis was to expand the knowledge regarding cultivation, reproduction methods and wintering options of the stevia plants. A field and a greenhouse experiments were staged with a focus on temperature indicators during the growing season and their impact on the total number of wintered plants. Simultaneously, an evaluation of the dry matter yield of the plants per an area unit and statistical processing and evaluation of the experiment results have been performed. Further, a determination of seed germination for Stevia rebaudiana in laboratory conditions has been conducted. The research results have shown that the plants obtained vegetatively are more suitable for cultivation due to a higher yield of the dry matter in both greenhouse as well as field conditions. The only pests invading stevia were the whiteflies appearing only in the greenhouse environment. Variable conditions were arranged for the wintering of the Stevia rebaudiana plants within the experiment; and in spite of the various materials and thermal insulation layers, the plants have not successfully wintered in an unheated environment. On the contrary, in the heated greenhouse space, most of the plants have successfully wintered. The stevia seed germination was low and proves the opinion of the majority of authors. The dry matter yields also matched the yields mentioned in the specialised literature.

Body size explains much of the interspecific variation in the physiology, behavior, and morphology of birds, such as metabolic rate, diet selection, intake rate, gut size, and bill size. Based on mass-specific metabolic requirements and relative energetic costs of activities, being a certain body size has both advantages and disadvantages. In particular, avian herbivores such as geese possess a relatively simple digestive system, consume foods with low digestibility and poor nutrient content, and have increased energetic demands compared to other bird taxa; therefore, any effects of body size on foraging strategies should be readily apparent in this foraging guild. The influence of body size on the behavior and management of Canada Geese (Branta canadensis) and Cackling Geese (B. hutchinsii) as avian herbivores has not been well studied. My dissertation explores the role of body size in comparative foraging behavior, habitat selection, and winter conservation planning for two congeneric geese, the Dusky Canada Goose (B. c. occidentalis; hereafter Duskys) and the Cackling Goose (B. h. minima; hereafter Cacklers). These two taxa share the same over-winter foraging environment (grass seed fields) in the same restricted geographic area (the Willamette Valley) during winter. Duskys and Cacklers differ by more than a factor of two in body size and have different relative bill sizes and social organization. Because of smaller body size, Cacklers have greater relative energy demands and less fasting endurance compared to Duskys; however, Cacklers have comparatively low energetic costs for flight and transport. Duskys, however, have higher total energy requirements than Cacklers. Additionally, Cacklers form large, high-density flocks and have a total over-wintering population size in the study area of about 200,000. Duskys occur in relatively small family groups and have a total over-wintering population size of about 13,000. My study demonstrated that interspecific differences in body size between Cacklers and Duskys was associated with differences in foraging behavior, movements, and habitat selection. Cacklers foraged a greater percentage of time (30%) in all habitats and across the entire winter compared to Duskys. Cacklers had higher peck rates (up to 100 pecks min⁻¹ greater) than Duskys in all foraging habitats expect pasture. The pecking rate of Cacklers was greatest in fields of young grass (200 pecks min⁻¹), which may indicate that Cacklers had relatively high intake rates in this foraging habitat. Based on differences in foraging behavior among habitats, Cacklers may have the foraging strategy of energy intake maximizers, whereas the foraging strategy of Duskys is more towards time-energy expenditure minimizers, at least for part of the winter. Cacklers moved across the landscape very differently from Duskys, exhibiting less site fidelity and greater commuting distances to foraging areas. Cacklers showed a preference for young grass during all periods of the winter, reaffirming that Cacklers are specialized grazers on short green forage, whereas Duskys preferred young grass and pasture. Fields of young grass were the preferred foraging habitat of Cacklers, had less standing crop biomass, and may have enabled higher foraging efficiencies, which may have led to higher intake rates. The ability of the landscape to support wintering geese changed across the winter because total available plant biomass fluctuated with the rate of grass regrowth. The estimated carrying capacity of the landscape for geese decline by almost one-half during mid-winter (mid-December to mid-February) compared to early winter or late winter periods. Although Cacklers have lower individual energy requirements compared to Duskys, due to a much larger target population size, Cacklers required 89% more foraging habitat than Duskys. Forage requirements encountered a bottleneck during mid-winter, when grass regrowth rates were low and day length was short. Commensurate with this pattern of forage availability, goose body condition declined during the mid-winter period. To support Pacific Flyway target populations for geese, approximately 18,000 ha of total grazing habitat in young and mature grass is needed in the Willamette Valley to support a total over-wintering population composed of 340,000 geese belonging to four subspecies. The role of body size in influencing the foraging behavior and decisions of over-wintering geese has important implications for conservation planning of goose populations. Small-bodied Cacklers are selective in field choice, yet more likely to redistribute across the landscape. Disturbances (e.g., hunting, hazing, or predation) will have a disproportionate effect on the movements of smaller-bodied geese compared to larger geese. These characteristics of Cacklers will make conservation planning to retain geese on public land more difficult. Coordinated management with private landowners and farming practices that maximize preferred goose foraging habitat on public lands may attract geese to utilize protected areas and minimize conflicts with agriculture in the Willamette Valley. Availability of resources during critical periods in winter is an important factor affecting the distribution of geese, but may affect small and large bodied geese differently. Management could be targeted during these critical time periods. By considering the role of body size in the context of life history characteristics, foraging behavior and habitat selection, appropriate management strategies can be developed and implemented to reduce the effects of agricultural depredation by geese, while promoting the future conservation of wintering geese in the Willamette Valley. / Graduation date: 2013

Seabirds are wide-ranging apex-predators and useful bio-indicators of marine systems. Nevertheless, changes are occurring in the marine environment, and seabirds require protection from the deleterious effects of climate change, fisheries, pollution, offshore development, introduced predators and invasive species. The UK supports internationally important populations of seabirds but also has vast wind and wave resources, therefore understanding how seabirds use the marine environment is vital in order to quantify the potential consequences of further exploiting these resources. In this thesis I first describe the range of wave energy converting devices operational or in development in the UK, and review the potential threats and benefits these developments may have for marine birds. I then synthesise data from colony-based surveys with detailed information on population dynamics, foraging ecology and near-colony behaviour, to develop a projection model that identifies important at-sea areas for breeding seabirds. These models show a positive spatial correlation with one of the most intensive at-sea seabird survey datasets, and provide qualitatively similar findings to existing tracking data. This approach has the potential to identify overlap with offshore energy developments, and could be developed to suit a range of species or whole communities and provide a theoretical framework for the study of factors such as colony size regulation. The non-breeding period is a key element of the annual cycle of seabirds and conditions experienced during one season may carry-over to influence the next. Understanding behaviour throughout the annual cycle has implications for both ecological theory and conservation. Bio-logging can provide detailed information on movements away from breeding colonies, and the analysis of stable isotope ratios in body tissues can provide information on foraging during the non-breeding period. I combine these two approaches to describe the migration strategies of northern gannets Morus bassanus breeding at two colonies in the north-west Atlantic, revealing a high degree of both winter site fidelity and dietary consistency between years. These migratory strategies also have carry-over effects with consequences for both body condition and timing of arrival on the breeding grounds. Finally, I investigate the threats posed to seabirds and other marine predators during the non-breeding period by collating information on the distributions of five different species of apex predator wintering in the Northwest African upwelling region. I describe the threat of over-fishing and fisheries bycatch to marine vertebrates in this region, and highlight the need for pelagic marine protected areas to adequately protect migratory animals throughout the annual cycle. In summary, the combination of colony-based studies, bio-logging, stable isotope analysis and modelling techniques can provide a comprehensive understanding of the interactions between individuals and the marine environment over multiple spatial and temporal scales.

The Thesis is treating the spreading of non-native waterfowl species into new ecosystems and factors, which influence that process. The impact of selected eco-geographic characteristics on the species diversity and on the numbers of non-native waterfowl individuals was analyzed on the results of the International Waterbird Census. Further, the influence of those characteristics on the numbers and population trends of selected 11 species of the Anatidae family in 17 European countries was assessed. The highest non-native waterfowl species diversity was recorded in countries of the Atlantic coast, i.e. France, Germany, the Netherlands, Belgium and also Switzerland. The main positive influence on their numbers makes the density of population and species diversity of wintering waterfowl. As to the number of non-native species individuals the main impact is produced by both, species diversity and the given latitude, too. It means that the largest number of individual exist in northern countries - Great Britain, Sweden, Germany and the Netherlands. Similar main influences have been traced with the family Anatidae, too, which have received special attention in the analysis, as it shows the highest number of non- native species. As to the main eco-geographic characteristics, having impact on the growth or...

Les activités humaines menacent gravement la biodiversité. Sous le terme de changements globaux, la sur-exploitation des populations et la destruction/dégradation des habitats arrivent en tête de liste des facteurs responsables de l’érosion de la biodiversité. Le changement climatique gagne en magnitude et ajoute une pression supplémentaire sur les espèces. En réponse à l’augmentation des températures du globe, les communautés se réorganisent suite au déplacement de la distribution géographique des espèces vers les pôles. Mais l’accumulation des pressions anthropiques est susceptible de produire des effets d’interaction limitant l’ajustement des communautés au réchauffement climatique. Dans ce contexte critique, la biologie de la conservation a pour but de concilier les activités humaines avec la conservation de la biodiversité. Dans cette thèse j’ai cherché à comprendre comment l’accumulation des pressions anthropiques peut limiter l’ajustement des communautés au réchauffement climatique et à identifier les solutions qui pourraient être mises en place pour faciliter leur adaptation à ce réchauffement. J’ai pris pour modèle d’étude les espèces d’oiseaux d’eau hivernants dans les pays du bassin méditerranéen. Ces espèces emblématiques bénéficient d’un dénombrement international destiné à suivre leurs populations en réponse aux prélèvements par la chasse et à la dégradation des zones humides dont elles dépendent. La Méditerranée est une région fortement anthropisée où l’utilisation des ressources naturelles exerce d’importantes pressions sur les zones humides et leur biodiversité. En réponse, les pays ont différentes stratégies pour protéger ces écosystèmes, ce qui fait de cette région un plan expérimental intéressant pour mesurer l’impact dans changements globaux sur l’assemblage des espèces en fonction des mesures de conservation mises en oeuvre. En étudiant la réponse des communautés au réchauffement climatique sous un gradient de perte/dégradation d’habitat, je montre que l’ajustement des communautés est réduit, voire empêché, par la dégradation des zones humides. La Convention Ramsar vise justement à protéger les zones humides et leur biodiversité en maintenant une exploitation raisonnée des ressources naturelles. En évaluant l’effet de cette convention, je montre que son efficacité à conserver les populations d’oiseaux est dépendante de l’implémentation d’autres outils de protection, mais que son rôle est crucial dans les pays où la législation environnementale est faible. Enfin, j’évalue la capacité des conventions internationales à faciliter l’ajustement des communautés au réchauffement climatique grâce à la réduction des pressions qui s’exercent sur les populations. J’ai comparé la réponse des communautés entre les pays ayant ratifié la Convention de Berne, ceux ayant engagé son application strictement réglementaire sous la Directive Oiseaux (Union Européenne) et ceux n’ayant pas ratifié ces conventions. Le résultat est clair, plus la réglementation est précise et strictement réglementaire, plus les communautés et les espèces strictement protégées s’ajustent à l’augmentation des températures.En conclusion, les activités humaines sont une menace pour la biodiversité, mais les mesures de conservation, en réduisant les pressions sur les populations facilitent leur adaptation au changement climatique. La conservation des oiseaux d’eau nécessite une collaboration internationale et l’établissement de lois strictement réglementaires protégeant les zones humides et les espèces, tout en assurant une utilisation durable des ressources. / Human activities seriously threaten biodiversity. In terms of global changes, overexploitation of populations and habitat destruction/degradation are at the top of the list of factors responsible for biodiversity loss. Climate change is increasing in magnitude and adding additional pressure on species. In response to the increase in global temperatures, communities are changing as a result of the shift in the geographical distribution of species towards the poles. But the accumulation of anthropogenic pressures is likely to produce interaction effects that limit community adjustment to global warming. In this critical context, conservation biology aims to reconcile human activities with biodiversity conservation. In this thesis I have investigate how the accumulation of anthropogenic pressures can limit the adjustment of communities to global warming and to identify solutions that could be put in place to facilitate their adaptation to this warming. I have used the wintering waterbird species in the countries of the Mediterranean basin as a model for my study. These iconic species benefit from an international census to monitor their populations in response to hunting and the degradation of the wetlands on which they depend. The Mediterranean is a highly anthropized region where the use of natural resources exerts significant pressures on wetlands and their biodiversity. In response, countries have different strategies to protect these ecosystems, making this region an interesting experimental plan to measure the impact in global changes on species assemblage based on conservation measures implemented. By studying the response of communities to global warming under a gradient of habitat loss/degradation, I show that community adjustment is reduced or even prevented by wetland degradation. The Ramsar Convention aims to protect wetlands and their biodiversity by maintaining a rational use of natural resources. In assessing the effect of this convention, I show that its effectiveness in conserving bird populations depends on the implementation of other protection tools, but that its role is crucial in countries where environmental legislation is weak. Finally, I assess the capacity of international conventions to facilitate community adjustment to global warming by reducing population pressures. I compared the communities' response between countries that have ratified the Bern Convention, those that have started its strictly regulatory application under the Birds Directive (European Union) and those that have not ratified these conventions. The result is clear, the more precise and strictly regulatory the regulations, the more communities and strictly protected species adjust to the increase in temperatures.In conclusion, human activities are a threat to biodiversity, but conservation measures, by reducing pressures on populations, facilitate their adaptation to climate change. Waterbird conservation requires international collaboration and the establishment of strictly regulatory laws to protect wetlands and species, while ensuring sustainable use of resources.

Les rizières constituent des habitats favorables pour les oiseaux d’eau, en particulier en tant que halte migratoire, zone de reproduction ou site d’alimentation hivernal. Dans ce dernier cas, la disponibilité des ressources alimentaires (grains de riz non ramassés, graines d’adventices ou invertébrés) semble être fortement influencée par les pratiques culturales post-récolte. Ce projet vise à tester des pratiques post-récolte alternatives au brûlage-labour traditionnellement mis en place en Camargue afin de mesurer les conséquences en termes de disponibilité de nourriture et de fréquentation des parcelles par les canards hivernants. Différents traitements post-récolte (inondation, brûlage, labour, disquage et leurs combinaisons) ont été testés. Nous avons réalisé un suivi de la quantité de graines (riz, adventices) disponibles au cours du temps, depuis la récolte en Septembre-Octobre jusqu'en Mars ainsi qu’un suivi de l'usage des parcelles par les canards pendant la journée et pendant la nuit. En parallèle, nous avons étudié les bénéfices agronomiques potentiels de certaines pratiques en interculure et nous avons cherché à identifier une solution mutuellement bénéfique, répondant aux besoins d’habitat d'hivernage des canards et à ceux des riziculteurs, le tout à moindre coût. / Rice fields provide foraging habitat to waterfowl during migration, breeding and wintering seasons. In the latter case, food availability (waste rice, weed seeds or invertebrates) seems to be strongly influenced by post-harvest agricultural practices. This project aims at testing alternative post-harvest practices to the traditional burning-mowing in the Camargue in order to assess their consequences in terms of food availability and field use by wintering ducks. Different post-harvest treatments (flooding, burning, mowing, disking and their combinations) were conducted. The amount of seeds (rice + weeds) available through time was assessed, from harvest in Sept-Oct until March, and duck use of these fields during the day and during the night was simultaneously monitored. In parallel, we studied potential agronomic benefit of specific post harvest practices and we searched a mutually beneficial solution that provides needed wintering ducks habitat and is acceptable to rice farmers with limited costs.

This thesis was conducted to evaluate important epidemiological features of Gastro-Intestinal Nematode (GIN) infections in Ontario sheep flocks; namely, the PeriParturient Egg Rise (PPER), overwintering of GIN free-living stages on pasture, and Anthelmintic Resistance (AR). Three main studies were carried out: a longitudinal study was conducted on six sheep farms to evaluate the PPER in ewes lambing in different seasons and to determine whether total plasma protein (TPP) levels and packed cell volume (PCV) were associated with increased fecal GIN-egg shedding. Secondly, a pilot-study was conducted on three farms to describe pasture-level environmental conditions and over-wintering survival and infectivity of free-living GIN larvae, especially Haemonchus contortus. Lastly, a cross-sectional study was conducted on 47 sheep farms in Ontario, to evaluate the frequency of AR, compare different diagnostic tests for AR, and evaluate management practices associated with AR. In the longitudinal study, the PPER was observed in winter, spring and autumn lambing ewes, though the magnitude and distribution of the PPER varied with season. Lower TPP and PCV values were associated with increased fecal GIN-egg counts. The pilot-study suggested that H. contortus larvae did not overwinter successfully on pasture, while other GINs, such as Teladorsagia sp., Trichostrongylus spp. and Nematodirus spp., were able to overwinter on pasture, and were infective the following spring. Resistance to ivermectin, fenbendazole and levamisole was demonstrated on 97% (28/29), 95% (19/20) and 6% (1/17) respectively of the farms tested; most of the resistance observed was found in Haemonchus sp. The Fecal Egg Count Reduction percentage following treatment was influenced by which mean (i.e. arithmetic vs. geometric) was used in the formula; use of pre-treatment in addition to post-treatment faecal egg counts was not influential. Both the fecal egg count reduction test and the larval development assay diagnosed resistance, but there was poor agreement between the two tests, as indicated by the Kappa test. The prior use of benzimidazoles on farms was associated with higher levels of fenbendazole resistance. The information generated in this thesis will be used to develop a parasite control program for sheep flocks in Ontario and to guide future research on GIN parasitism. / New Directions - Ontario Ministry of Agriculture, Food and Rural Affairs; Ontario Sheep Marketing Agency; Ontario Agriculture Centre Canada; Merial; Animal Health Strategic Initiative - University of Guelph Partnership; Undergraduate Research Assistantship; Gartshore Memorial Sheep Scholarship;

The aim of the thesis was to document patterns in breeding and migration in Swedish Canada geese Branta canadensis, to explain these against the genetic and historical background of the population, and to test predictions of hypotheses pertaining to parental investment. The Canada goose population in Sweden was founded by the introduction of a few individuals in the 1930's. DNA fingerprint similarity between geese breeding in Sweden was on average at the same level as between inbred close relatives in other wild bird species. The genetic variability of the population appeared to be considerably reduced in comparison to that of Canada geese breeding in North America. Dispersal and migration patterns were studied using plastic neck-bands that could be identified at long distance. Most Canada goose females nested at the lake where they grew up. Males were more prone to disperse than females, although most of them still returned to breed close to their area of origin. Geese from three breeding areas in Sweden had different winter distributions, although wintering areas overlapped considerably. Individual geese tended to return to the same wintering area as they had used in previous years. The females' investment in the egg clutch was related to the migration distance from spring foraging areas to the nesting area, suggesting an energetic cost of migration for egg production. Within breeding seasons, clutch size decreased with later initiation of nesting, but only in years with early breeding. A probable reason for this decrease was that body reserves available for egg production were larger in early layers. In years with late breeding, clutch size did not decrease, most likely because late-nesting females could supplement their body reserves by foraging on fresh vegetation. Nest defence intensity was studied by recording the behaviour of the female geese when a human approached the nest. The results largely confirmed predictions for nest defence intensity extracted from parental investment theory. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1993, härtill 6 uppsatser</p> / digitalisering@umu

Viticultural practices such as trunk girdling and shoot topping along with defoliation, shading and node number per vine treatments were used to alter the carbohydrate physiology of mature Chardonnay grapevines growing in the cool climate of Canterbury, New Zealand. The timing of vine defoliation in the season previous to fruiting decreased concentrations of over-wintering carbohydrate reserves (mostly starch) in both the trunks and roots of grapevines. Roots were particularly sensitive, with defoliation as early as 4 weeks after bloom in the previous season reducing starch concentrations to 1.5%Dwt at bud burst compared with 17%Dwt in non-defoliated vines. In contrast, partial vine defoliation as early as bloom in the previous season reduced root starch concentrations to 4-7%Dwt at bud burst compared with 15%Dwt in non-defoliated vines. Vine shading and trunk girdling treatments at bloom in the previous season, resulted in small reductions in root starch concentrations (16%Dwt) compared with non-shaded and non-girdled vines (19%Dwt), but shoot topping did not. Study across three growing seasons established that higher concentrations of over-wintering trunk and root carbohydrate reserves were associated with warmer and sunnier weather in the previous growing season. Individual shoot leaf removal at either the beginning or towards the end of the inflorescence initiation period, reduced shoot starch concentrations to 3-6%Dwt compared with 11 %Dwt for no leaf removal, such reductions persisted through to the following season. Shoot topping at the start of the initiation period had no effect on shoot carbohydrate accumulation, but trunk girdling temporarily increased shoot starch concentrations during the first 31 days after treatment. Reductions in over-wintering trunk and root carbohydrate reserves were associated with a reduction in inflorescences per shoot and flowers per inflorescence in the following season, the reduction as much as 50% compared with non carbohydrate stressed vines. While there were strong linear or curvilinear relationships between the concentration of starch in trunks and roots at bud burst and inflorescences per shoot and flowers per inflorescence, in case the of inflorescences per shoot, there was not an immediate cause and effect because inflorescences were initiated in the previous season. Individual shoot leaf removal during the inflorescence initiation period illustrated that leaf removal directly inhibited the initiation of inflorescences in latent buds. Shoot carbohydrate measurements showed a strong curvilinear relationship to the number of inflorescences per shoot, with a threshold starch concentration of 10-12%Dwt during the inflorescence initiation period required for a maximum number of inflorescences per shoot. Furthermore, examination of individual node positions emphasised the importance of the subtending leaf on the initiation of inflorescences within the latent bud. The number of inflorescences per shoot post bud burst was reduced on vines that were both carbohydrate reserve stressed (by previous season's defoliation) and had a high node (108) number retained per vine after winter pruning compared with little or no reduction in inflorescences per shoot on carbohydrate reserve stressed vines that had a low (20) node number per vine. The reduction in inflorescences per shoot on high node vines was associated with reduced carbohydrate reserves and reduced shoot vigour (thinner and lighter shoots). Flowers per inflorescence were reduced by as much 50% in response to lower overwintering carbohydrate reserves. Fewer flowers per inflorescence were attributed to a reduction in primary branching of the inflorescence and also a reduction in flowers per branch. Strong linear relationships between the concentrations of starch in trunks and roots and flowers per inflorescence indicate that the determination of flowers per inflorescence, unlike inflorescences per shoot, may be dependent on the level of overwintering carbohydrate reserves. This is most likely due to changes in branching of the inflorescence and individual flower formation occurring during the bud burst period. Per cent fruitset was not affected by reductions in carbohydrate reserves, so fewer inflorescences per shoot and flowers per inflorescence resulted in reduced vine yield. The findings of this thesis indicate that changes in the level of carbohydrate production and partitioning in response to a range of viticultural management practices and seasonal weather contribute to seasonal variation in grapevine flowering and yields in New Zealand's cool climate environment. The relationships between carbohydrate reserves and flowering illustrate the potential to use this information to predict grapevine flowering and forecast yields. The practical implications of this research illustrate that the viticulturist must manage grapevines not only for the current crop, but also for subsequent crops by maintaining sufficient carbohydrate reserves for balanced growth flowering and fruiting from season to season.