Dissertations / Theses on the topic 'Phenology'

Understanding the relationships between solitary bees’ flight phenology and flowering phenology is important in the context of global warming. Using Swedish citizen science data, observations of oligolectic solitary bees and flowering phenology were used together with temperature data. All five bees studied had flight period that overlapped with the flowering period their corresponding host plant. None of the species were affected by the temperature, although there was a correlation between earliest observations of flowering phenology and flight phenology. The later the flowering observation was made, the later the flight observation was made. No correlation was found between the length of flight period and length of the flowering period. Increasing temperature is not the only factor that effects flight phenology and flowering phenology.

3 pp.
Phenology is defined and described in terms of how we use observations in education and research. Suggestions for implementing phenology lessons using examples from 4-H youth development and Master Gardener and citizen science training.

The rate of insect development (phenology) is strongly associated with temperature. Within the biological literature, phenologies are estimated largely on the basis of sparsely located point meterological data. The significance of incorporating a geographical dimension was explored in two application areas where phenologies are used, pest risk assessment (PRA) and integrated pest management (IPM). Colorado beetle (leptinotarsa decemlineata) and codling moth (Cydia pomonella) were used as representative non-indigenous and indigenous test organisms. To ensure relevance to both pest risk assessment and integrated pest management applications, phenology models were run using daily meterological data throughout England and Wales. Interpolation was chosen as an efficient means to create spatial temperature 'surfaces' from distributed daily maximum and minimum temperature data observed at a subset of 174 meteorological stations. Because insect pests are known to be highly sensitive to temperature, considerable attention was paid to minimising the errors generated as part of this process relative to that in previous applied agricultural studies. Comparisons between the commonly used trend surface and inverse distance weighting methods of interpolation were made with partial thin plate splines and ordinary kriging. Unlike earlier work, automatic parameter selection was used to calibrate all the interpolation techniques and care was taken to ensure the comparability of estimated temperature values. Error in estimates by all methods was reduced using a number of guiding topo-climate and land cover covariates. The most favourable estimates of maximum and minimum temperatures throughout the country and over the annual cycle were partial thin plate splines, with daily average r.m.s. accuracies computed using jack-knife cross-validation of 0.8°C and 1.13°C respectively. Partial thin plate splines were also found to be more computationally efficient than both inverse distance weighting and de-trended ordinary kriging. This use of jack-knife cross-validation was assessed using a fully independent data set of a further 100 data points, and was found to be statistically comparable. Providing the interaction between phenology models and sequences of geographically relevant temperature data at this daily step and national coverage necessitated the construction of tailor made research software for the project. The coupled temperature interpolation/phenology modelling system was used to provide a range of outputs to explore the accuracy of predicted phenologies over space and time.

Phenology, the study of timings of natural events, is the longest written biological record in the UK. It has thus proved invaluable in revealing how species have responded to recent climate warming. I have played a major role in achieving Scientific 'legitimacy' for the subject and there is a growing urgency to demonstrate climate induced effects to both a scientific and a general audience. My phenological publications fall into four broad areas. 1 . Utilising historic data. Many historic data sets have languished in obscurity for >50 years. Identification and examination of some of these data has revealed how biological events responded to past fluctuations in temperature. The typical response of c.6 days earlier for each 1°C warming has enabled a prediction of response to future climate. National data sets have given greater confidence in these results. 2. Bird phenology. Bird data, particularly that on migration timing, forms a huge resource of phenological material. I have examined the role of temperature in bird phenology and on migration patterns from various sources of data and have begun to extend these studies through international collaboration (two further papers 'in press'). In general, the response of birds is more variable and not as great as that of plants and invertebrates. 3. Other taxa. Post-war changes have already taken place in the timing of a wide range of taxa. In some instances events are at least three weeks earlier. These results have encouraged me to resurrect a phenology network after a 50-year break (www.phenology.org.uk). 4. Increasing awareness. Changes in phenology are readily understood by various sectors of the public and are a good vehicle with which to demonstrate climate change. The UK Government has now accepted phenological events as Climate Change Indicators.

Variation in phenology is linked to the timing of environmental variables and influences survival at both the individual and colony level. Therefore, understanding a species' annual cycle is vital to its ecology and conservation. By reviewing literature on Pygoscelis penguin phenology in Chapter 1, I identify major gaps, both spatially and temporally, in our knowledge of the timing of events in the three species (Adeélie, Pygoscelis adeliae; chinstrap, and Pygoscelis antarctica; gentoo, Pygoscelis papua): particularly, 1) during the guard phase, 2) their behaviour in winter, 3) the phenology of colonies inhabiting locations away from scientific bases, and 4) the general phenology of chinstrap penguins. Chapter 2 assesses which time-lapse camera methods are most relevant to seabird research, highlighting the capabilities and limitations of cameras in past studies and how they may be best applied to future research. Chapter 3 examines the timing of the guard phase in gentoo penguins and how chick aggregation behaviours vary across several sites. Chapters 4 and 5 show variation in winter abundance at breeding sites in both gentoo and Adélie penguins related to abiotic factors and colony location. Lastly, Chapter 6 fills in gaps in the known timing and duration of phenology events in gentoo and chinstrap penguins across their full latitudinal ranges, while relating these timings to chick survival. In the conclusion, I summarize the main findings of the thesis, focusing on three major themes that were observed across the four data chapters and their implications: 1) behaviours are not consistent across colony locations 2) nor between years, and these behaviours depend on 3) local environmental conditions. I then synthesize these empirical findings from each of these chapters, discuss the implication of these findings to ecological theory and conservation policy, highlight some of the limitations of these studies, and recommend possibilities for future research.

Savannas are mixed tree-grass systems and as one of the world's largest biomes represent an important component of the Earth system affecting water and energy balances, carbon sequestration and biodiversity as well as supporting large human populations. Savanna vegetation structure and its distribution, however, may change because of major anthropogenic disturbances from climate change, wildfire, agriculture, and livestock production. The overstory and understory may have different water use strategies, different nutrient requirements and have different responses to fire and climate variation. The accurate measurement of the spatial distribution and structure of the overstory and understory are essential for understanding the savanna ecosystem.

This project developed a workflow for separating the dynamics of the overstory and understory fractional cover in savannas at the continental scale (Australia, South America, and Africa). Previous studies have successfully separated the phenology of Australian savanna vegetation into persistent and seasonal greenness using time series decomposition, and into fractions of photosynthetic vegetation (PV), non-photosynthetic vegetation (NPV) and bare soil (BS) using linear unmixing. This study combined these methods to separate the understory and overstory signal in both the green and senescent phenological stages using remotely sensed imagery from the MODIS (MODerate resolution Imaging Spectroradiometer) sensor. The methods and parameters were adjusted based on the vegetation variation.

The workflow was first tested at the Australian site. Here the PV estimates for overstory and understory showed best performance, however NPV estimates exhibited spatial variation in validation relationships. At the South American site (Cerrado), an additional method based on frequency unmixing was developed to separate green vegetation components with similar phenology. When the decomposition and frequency methods were compared, the frequency method was better for extracting the green tree phenology, but the original decomposition method was better for retrieval of understory grass phenology. Both methods, however, were less accurate than in the Cerrado than in Australia due to intermingling and intergrading of grass and small woody components.

Since African savanna trees are predominantly deciduous, the frequency method was combined with the linear unmixing of fractional cover to attempt to separate the relatively similar phenology of deciduous trees and seasonal grasses. The results for Africa revealed limitations associated with both methods. There was spatial and seasonal variation in the spectral indices used to unmix fractional cover resulting in poor validation for NPV in particular. The frequency analysis revealed significant phase variation indicative of different phenology, but these could not be clearly ascribed to separate grass and tree components.

Overall findings indicate that site-specific variation and vegetation structure and composition, along with MODIS pixel resolution, and the simple vegetation index approach used was not robust across the different savanna biomes. The approach showed generally better performance for estimating PV fraction, and separating green phenology, but there were major inconsistencies, errors and biases in estimation of NPV and BS outside of the Australian savanna environment.

Seed production and germination of some timber tree species were studied in Ghana for possible prediction of seed yield and natural regeneration. Seed phenology in 13 species was monitored for two years, using permanent seed traps in two forest sites. Seed germination tests were conducted in neutral, green shade and dark in shade houses for 20 species. In the forest, germination was tested in forest gaps receiving different irradiances. Fruiting frequency ranged from twice in each year to supra-annual fruiting. Fruiting periods for species were consistent between years. Fruiting synchrony was higher among individuals of a population than between sites for the same species. Fecundity differed between years for the majority of species and between sites for species common to both sites. Premature fruit abscission was quite common. Maximum seed weight and percentage germination occurred during peak fall of mature seeds. Seeds of the majority of species germinated equally in light and dark and also in neutral and low red: far red ratio. These included some species previously classified as pioneers. In the forest germination was depressed in a large clearing for the majority of species. The use of photoblastic germination alone to define pioneers leads to a smaller group of pioneer species than is presently recognised. Large gaps due to logging may discourage natural regeneration.

Changes in phenology due to climate warming could disrupt temporal overlap between interacting organisms when previously synchronized species respond to climate change at different rates. Phenologies of plants and insects are known to be sensitive to temperature and/or timing of snowmelt, with warmer temperatures and earlier snowmelt generally advancing spring flowering and emergence; however, some groups of pollinators, such as solitary bees, have been little explored in this context. One striking aspect of eastern hardwood forests is the emergence of understory wildflowers each spring, most of which rely, at least to some extent, on wild native pollinators for seed set. Without an understanding of the environmental drivers of phenology of these species, we have little ability to predict whether pollinators will continue to be well synchronized with flowering as the climate changes. In this study, I determined how spring temperatures and timing of snowmelt influence the phenology of spring wildflowers, activity of bees, and their temporal overlap in Gatineau Park, Québec. From 2013 to 2018, I characterized bee activity phenology and flowering phenology of understory plants in multiple study plots, focusing on early-flowering Anemone spp. and later-flowering Trillium grandiflorum. The sampled bee community was dominated by Andrena, Lasioglossum, and Nomada, all of which have similar activity periods. Degree-day accumulation was a better predictor of Anemone and Nomada phenology than were day of year or snowmelt date, whereas T. grandiflorum appeared to be more sensitive to photoperiodic cues; since day of year was the variable that best described its phenology. Activity periods of Andrena and Lasioglossum were equally well described by degree-day accumulation and by day of year. No taxon’s phenology was best predicted by snowmelt date. Despite these differences among taxa in the identities of the best predictors of phenology, bee activity and plant flowering phenologies responded at similar rates to interannual and among-site variation in snowmelt date and early spring temperature. Temporal overlap between flowering and bee activity was similar over the years of this study and was affected neither by snowmelt date nor by temperature. These results suggest that interacting plant and bee taxa may respond to different environmental variables but still maintain their synchrony under the conditions recorded so far.

Worldwide harbour seal populations are showing differing and fluctuating trends in abundance, but the drivers of change remain uncertain. Within the Moray Firth, NE Scotland, count surveys carried out over the last 20 years highlighted the development of a new breeding site, providing a unique opportunity to carry out an individual-based study of harbour seal demography and pupping phenology using photo-identification techniques within a mark-recapture framework. Sightings of individual seals suggested that a large proportion of harbour seals are year-round residents at haul-out sites. Both sexes displayed high levels of between-year breeding site fidelity as well as seasonal variation in their haul-out behaviour. Apparent sex-specific survival rates (0.89♂, 0.97♀) and birth rates (0.88) were high. There was a strong correlation between lactation durations and the timing of pupping, suggesting that shifts in pupping phenology are a result of energetic constraints. This highlights the potential for using the timing of pupping as an indicator of ecosystem conditions. This study provided the first concurrent real-time estimates of survival and fecundity in a naturally regulated population of harbour seals. Demographic parameters and physiological responses indicate that prevailing conditions within the Moray Firth are favourable, and that this population should be recovering. However, observed patterns may also be an artefact of the long-term decline having caused an increase in per capita food availability through the reduction in intra-specific competition. This study highlights the current and long-term importance of individual-based data in understanding population dynamics. Through the identification of sentinel sites around the world, harbour seals could provide a single-species indicator of coastal ecosystem conditions in the Northern Hemisphere.

Amphibian breeding phenology has generally been associated with temperature and rainfall, but these variables are not able to explain all of the variation in the timing of amphibian migrations, mating and spawning. This thesis examines some additional, previously under-acknowledged geophysical variables that may affect amphibian breeding phenology: lunar phase and the K-index of geomagnetic activity. A serendipitous observation of a large earthquake during the amphibian breeding season enabled a rare record of animal behaviour prior to an earthquake and led to an investigation into the effect of seismicity on amphibians. Data were collected on breeding migrations at three sites in the UK and Italy for frogs (Rana temporaria) and toads (Bufo bufo). Additional data were collated from published literature. Data on the arrivals of two newt species (Triturus cristatus and Lissotriton helveticus) were also analysed. Lunar phase was found to be important in Rana temporaria and Bufo bufo, with more individuals migrating, in amplexus and spawning around the full moon. Newts' response to the full moon was less clear. A meta-analysis of published data revealed that the effect of the lunar cycle on amphibians may be more prevalent than previously supposed and is species-specific, depending on the unique ecology of each species. The effects of the K- index on amphibian reproduction are unclear because of the low number of days when geomagnetism was high. Five days before a large earthquake in L' Aquila, Italy the majority of toads left the breeding site, only re- appearing when the earthquake was over. Numbers of toads were significantly correlated with days since the earthquake but not with weather variables. Finally I attempted to use the variables of interest (two measures of moon phase, plus the K-index of magnetic activity), along with weather variables to construct statistical models of amphibian breeding phenology and to predict arrivals and spawning / amplexus in single years based on the models. This met with variable success; there was a high variability between years in the ability of the models to predict breeding phenology, which could be due to site-specific factors, unmeasured environmental variables, or an endogenous component to breeding phenology.

Thesis (Ph.D.)--Boston University
PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
In response to warmer temperatures and altered precipitation, plants and animals have adjusted their phenologies, timing of annual biological events, over the past few decades. However, a long-term perspective is needed. I combined observations from Concord, MA from the journals of Henry David Thoreau in the 1850s with other naturalists, to create the longest-known record of migratory bird arrivals in North America. Twenty-two passerine species were found to be highly variable with some arriving earlier in warm years than cold years, and others not changing at all. Banding data from the Manomet Center for Conservation Sciences, in southeastern MA, provided a robust dataset from 1970 to the present to further explore more detailed patterns in bird migrations. Most bird species in this record are experiencing significant population declines, and several arrive earlier in warm years. However, closely related birds did not behave in a manner similar to one another, and there is little evidence to support the hypothesis that species with flexible migration times would be more successful, a pattern found in European species. It is important to consider phenological changes at multiple trophic levels. Investigation of insect emergence dates collected by the Japan Meteorological Agency provided the paradoxical result that insects that emerge earlier in warm years are emerging later now than they did 50 years ago, even though temperatures are getting warmer. Sampling issues associated with strong population decline are the likely explanation. Plants are known to be quite responsive to temperature, yet one of the most primitive groups of plants, ferns, has remained unstudied from the perspective of recent climate change. I examined phenological and physiological responses of two fern species to a range of experimental water and temperature regimes. The cinnamon fern, Osmunda cinnamomea , generally exhibited greater phenological flexibility and hardiness under higher temperatures and drought as compared to the royal fern, Osmunda regalis . Taken together, this dissertation research demonstrates that organisms at various trophic levels respond differently to climate change. Therefore, the response of each species needs to be evaluated individually and in relationship to other species.
2031-01-01

Several reproductive processes of tetraploid Grindelia camporum were investigated. This plant is a potential resin crop for the southwestern United States. Field observations of 100 flower heads from unopened buds through 100% achene dispersal were made. It was found that individual flower heads are available for pollination for approximately 5 days but all disc florets are open for only 1 day. On average, achenes mature in 22 days and are dispersed 53 days after flowering. Fourteen-hundred hand-pollinations were also made on plants from 6 wild populations of G. camporum grown in a greenhouse and shade house. Estimates of fertility and crossability of populations were made based on achene number and achene weight data from these crosses. All populations studied were interfertile and no evidence of outbreeding depression in between -population crosses was found. It is shown that tetraploid G. camporum is self-incompatible and requires manipulation for achene set.

Every year, the oceans absorb one quarter of the carbon dioxide (CO2) emitted to the atmosphere by human activities. This CO2 sink is part of a very active, natural carbon cycle, through which phytoplankton fix CO2 into organic matter in the surface layer of the ocean. Phytoplankton cells tend to aggregate and sink from this surface layer, exporting carbon to the deep ocean and regulating the atmospheric CO2 on long time scales. In the light of the recent unequivocal evidence of global warming, it appears essential to assess its impact on phytoplankton community and to evaluate the subsequent feedback through the oceanic carbon cycle. In recent years, phytoplankton phenology has been suggested as a systematic indicator to monitor the state of the pelagic ecosystem and detect changes triggered by perturbation of environmental conditions. For the first time, the phenology of phytoplankton growing season is estimated at the global scale using remote-sensing ocean colour data. The tropics and subtropics present generally long growing season (15-20 weeks) of low amplitude (< 0.5 mg m−3), whereas the high-latitudes show short growing season (< 10 weeks) of high amplitude (up to 7 mg m−3). Correlation analyses suggest a close coupling between the development of the growing season and the seasonal increase in insolation in the North Atlantic and Southern Ocean. In the tropics and subtropics, light is rarely limiting and the growing season is controlled by nutrient supply enhanced by water mixing. Over the decade 1998-2008, the duration of growing season shows large interannual variability of up to ± 10 weeks. Globally, positive anomalies follow the major 1997-98 El Ni˜no-La Ni˜na events and persist until 2001. Positive phases of climate indices such as the North Atlantic Oscillation and the Southern Annular Mode, associated with enhanced water mixing and nutrients supply, generally sustain longer growing season. Using in-situ observations, we show that the export of carbon can be related to the length of the phytoplankton growing season, with largest export in regions where the growing season is shortest and the blooms most intense. Using satellite observations, from the sensors CZCS and SeaWiFS, we estimate that North of 45◦S, the phytoplankton growing season increased by 2.4 weeks on average between the periods 1979-1986 and 1998-2008. Longer growing seasons are associated with regional patterns of surface warming on the same time scale. We infer from in-situ data a decrease in carbon export of 0.6 Pg C yr−1 (excluding the Southern Ocean) over two decades. This represents an unexpected, and important, feedback between physical and biological processes in the ocean: global warming modifies phytoplankton growth, reducing the capacity of the ocean to absorb atmospheric CO2 leading to a probable aggravation of global warming. Finally, phenological characteristics of the phytoplankton growing season are used to resolve Sverdrup’s critical depth model. Mixed layer integrated plankton community respiration Rmld and net community production NCPmld are estimated at the global scale using remote-sensing data of incident irradiance level and primary production, and a global mixed layer depth climatology. NCPmld estimates agree with in-situ observations and model results in the tropical and North Atlantic regions. The model estimates a net autotrophic imbalance of + 0.65 Pg C yr−1 in the North Atlantic and a net heterotrophic imbalance of − 1 Pg C yr−1 for the whole tropics and subtropics.

The seasonal timing of plant development is regulated by environmental cues. Flowering time is influenced by the temperature and photoperiod experienced during vegetative growth, while germination timing is affected by temperatures during seed maturation and after dispersal. The timing of each developmental transition also determines seasonal conditions experienced during subsequent life stages, however the significance and stability of these interactions are not well understood. This work aimed to further an understanding of the environmental regulation of plant phenology by creating a multi-stage life history model based on Arabidopsis thaliana. Laboratory and field studies were used to inform predictive models of seed development and seed dormancy. The time required to complete seed development was mainly affected by temperature, and was therefore sensitive to seasonal flowering time. Mean daily temperatures at the end of seed maturation had the greatest influence on rates of primary dormancy loss, and post-dispersal temperatures determined rates of secondary dormancy induction. Germination probabilities were predicted by modelling frequencies of primary and secondary dormancy within the seed population. This revealed an abrupt switch from low to high germination when mean daily temperatures exceeded 14°C. Thermoinhibition was also predicted at high temperatures due to rapid secondary dormancy induction. Combining models with a previously described model of flowering time provided a framework for investigating the effects of perturbations on entire life history phenology. Seed set timing in spring and winter annuals was consistently predicted to coincide with mean daily temperatures of 14°C in locations across Northern Europe, resulting in the production of both dormant and non-dormant offspring. Phenotypic plasticity at each growth phase also served to buffer against modest perturbations in germination date, flowering date, and climate in order to maintain these specific dispersal conditions. This result was interpreted as evidence for a robust bet-hedging germination strategy.

Field experiments were conducted in 2007 to evaluate a cantaloupe (Cucumis melo L.) plant development model as a function of heat units accumulated after planting (HUAP). Field experiments were conducted in 2007 in the Yuma Valley, Arizona (32° 42' N, 114° 42' W), about 150 feet (~ 32 m) elevation in four commercial cantaloupe fields managed by a cooperator-grower using four varieties. Plant measurements were made on regular 14-day intervals and the following growth stages were identified in relation to plant measurement data collection: pre-bloom, early fruit set, early netting, and physiological maturity (harvest). The model was evaluated by comparing the observed HUAP versus the predicted HUAP values using a repeated measures design. Mean differences within each sampling stage were separated using the Fishers’ protected least significance difference (LSD) test at P≤ 0.01. In addition, regression models were performed for all in-season data collected and the accuracy of the model was evaluated on the basis of the R² values with a specified level significance (α = 0.01). No statistical differences were found between the observed phenological data and the predicted values from the model throughout the study period. Also, the model presented an overall accuracy of 54 ± 37 HUAP (2 ± 1 day) in predicting cantaloupe-harvesting time. It can be concluded that the model can be used as a useful tool to assist cantaloupe growers in predicting and identifying critical stages of growth for irrigated spring cantaloupe crops in Arizona and the desert Southwest.

Spring plant phenology is often used as an indicator of a community response to climate change. Remote data and low-resolution climate models are typically used to predict phenology across a landscape; however, this tends to miss the nuances of microclimate, especially in a mountainous area with heterogeneous topography. I investigated how inter-annual variability in regional climate affects the distribution of microclimates (i.e., areas <100m2) and spring plant phenology across a 6400-hectare watershed within the Western Cascades in Oregon. Additionally, I created species-specific models of bud break at the microclimate scale, that could then be applied across a wider landscape. I found that years with warm winters, few storms and low snowpack have a homogenizing effect on microclimate and spring phenology events, and that bud break models developed at a local scale can be effectively applied across a broader landscape. This thesis includes previously unpublished coauthored material.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Os padrões climáticos têm sofrido alterações em escala global nas últimas décadas e consequências graves sobre o desenvolvimento de diversas espécies vegetais têm sido observadas. A intensificação dos avanços fenológicos no hemisfério norte tem despertado o interesse sobre a compreensão da fisiologia da dormência de espécies temperadas quando submetidas a regimes de aquecimento. A proposta desse estudo foi comparar os padrões regionais de temperatura e floração de cultivares de macieiras cultivadas em climas contrastantes, a partir de uma extensa base de dados de temperatura e fenologia. Assim, foi possível compreender como a temperatura controla o processo de floração e diagnosticar as zonas de produção mais vulneráveis ao aquecimento. Séries históricas de temperatura foram coletadas na Europa Ocidental (inverno frio), Marrocos e no sul do Brasil (inverno quente). Datas de ocorrência de dois estágios de floração e o tempo transcorrido entre eles foram analisados. Verificou-se o aquecimento de todas as áreas da Europa Ocidental na primavera, e um leve aquecimento do período invernal na zona sul dessa região. Nesses locais os avanços das datas de floração e o curto tempo de floração ocorreram pela elevação das temperaturas primaveris. A região sul mostrou-se mais vulnerável a futuros aquecimentos. No Marrocos e sul do Brasil o aquecimento foi mínimo nas últimas décadas sendo o inverno mais afetado. Leves mudanças fenológicas e longos períodos de floração estiveram associados às temperaturas invernais. Padrões de fenologia e temperatura intermediárias foram observados no Marrocos. Por outro lado, estudo complementar foi conduzido no Brasil e na França visando compreender o mecanismo de dormência da macieira, os fatores intrínsecos que a controlam, além de analisar as variabilidades regionais e varietais. A cinética da dormência foi determinada em gemas vegetativas por “One-bud cutting test” e em gemas florais por “Tabuenca’s test”. Gemas vegetativas apresentaram dormência oscilante durante outono-inverno-primavera na França, sendo profunda no inverno. No Brasil, as gemas vegetativas apresentaram dormência com variações amenas no período equivalente e com profundidade superficial. O aumento significativo do peso fresco e seco dos primórdios florais caracterizou a fase transitória entre endo- e ecodormência. No entanto, o estabelecimento da ecodormência esteve relacionado com o aumento significativo do peso seco e da capacidade de reidratação dos primórdios florais. A transição entre essas fases foi acelerada no Brasil e mais lenta na França. Ainda, a partir de dados históricos de temperatura e fenologia, foram selecionados modelos fenológicos sequenciais capazes de estimar regionalmente as datas anuais de floração em ambos os hemisférios. Dois modelos foram validados para a estimação do estágio de floração BBCH 61 (NHGoldenF1) e BBCH 65 (NHGoldenF2) de Golden Delicious, na Europa Ocidental. Esses modelos apresentaram elevada acuracidade e apresentaram eficiência superior aos modelos termais. Considerando um cenário RCP de incremento intenso da temperatura até o final do século, observou-se tendência de alongamento do período de acúmulo de frio, principalmente em Nîmes, e antecipação das datas de floração em Angers, até o final desse século, segundo os dois modelos NH. Em ambos os cenários e locais, observou-se redução significativa da fase de ecodormência até o final desse século, com os menores valores registrados em Nîmes. Essa perspectiva de mudanças na temperatura na região Mediterrânea da Europa predispõe futuramente o alongamento do período de floração, resultando distúrbios fisiológicos característicos de regiões de clima ameno hoje. Outros conceitos de modelos ou a inclusão de múltiplos fatores durante a parametrização devem ser considerados em um futuro breve, haja vista ainda, que o agravamento 12 climático na Europa, poderá comprometer a aplicabilidade dos modelos sequências, como se observou na atual situação climática do sul do Brasil.
Weather patterns have changed globally in recent decades causing serious consequences on the development of several plant species. The intensification of phenological advances in the northern hemisphere has raised interest in the understanding of dormancy physiology in temperate species when subjected to warming regimes. The purpose of this study was to compare regional patterns of temperature on the flowering of apple tree cultivars grown under contrasting climates, using an extensive database of temperature and phenology records. Thus, it was possible to understand how temperature controls the flowering process and identify the areas most vulnerable to warming. Historical temperature series collected for Western Europe (cold winter), Morocco and Southern Brazil (warm winter) were used. Historical dates of two flowering stages and the time between them were analyzed. All areas in Western Europe experienced warming in the spring, whereas a slight warming of winter was found in the mild areas. The observed advancement of blooming dates and the short blooming time were linked to spring temperature increase in Western Europe, with the southern region being more vulnerable to future warming. In Morocco and Southern Brazil minimal warming was found in recent decades but winter was most affected. Weak phenological changes and long flowering periods were associated with winter temperatures. Phenology patterns and intermediate temperatures were observed in Morocco. Moreover, an additional study was conducted in Brazil and France to understand the mechanism of dormancy in apple trees, the intrinsic factors that controls it, and to analyze the regional and varietal variability. The kinetics of dormancy in vegetative buds was determined by a "One-bud cutting test" and in floral buds by "Tabuenca's test." Vegetative buds showed fluctuating dormancy during autumn-winter-spring in France, which was deeper in winter. In Brazil, the vegetative buds showed weak variations and shallow depth in the equivalent period. The significant increase in fresh and dry weight of flower primordia characterized the transitional phase between endo- and ecodormancy. However, ecodormancy establishment was related to the significant increase in dry weight of floral primordia and their ability to rehydrate. The transition between these phases was fast in Brazil and slower in France. Sequential models, able to estimate annual blooming dates in both hemispheres were selected from historical temperature and phenology data. Two models were validated to estimate the stages BBCH 61 (NHGoldenF1) and BBCH 65 (NHGoldenF2) of Golden Delicious in Western Europe. These models showed high accuracy and greater efficiency in relation to thermal models. Considering a CPR scenario of intense increase in temperature by the end of this century, there was estimated a trend to extend the period of chill accumulation, especially in Nîmes, and advance dates for flowering in Angers, by the end of this century, according the two NH models. Under both scenarios and locations, there was a significant reduction in the ecodormancy phase, with the lowest values recorded at Nîmes. The projected changes in temperature in the mediterranean region of Europe can extend the flowering period, resulting in physiologic disturbances as today in mild climate. Other concepts of models and/or the inclusion of multiple factors in the model should be considered in the near future, considering that warming in Europe may compromise the applicability of the sequential models, as observed currently in southern Brazil.

Predation is an important ecological process that shapes life-history traits, community dynamics, and species coexistence and therefore has been suggested to explain many patterns in avian ecology. Although many studies have reported spatial, temporal, or interspecific patterns in nest predation, relatively few studies have been designed to identify the specific mechanism(s) that underlie these patterns. I examined mechanisms underlying the risk of nest predation in birds by (1) reviewing nine of the most commonly cited hypotheses to explain spatial, temporal, and interspecific variation in the risk of nest predation, (2) conducting a comparative analysis of the nest-concealment hypothesis to examine which methodological issues, extrinsic factors, and species traits influence whether or not foliage density affects the risk of nest predation, and (3) testing six mechanistic hypotheses to determine the underlying cause(s) of intra-seasonal decreases in the risk of nest predation.Many of the hypotheses invoked to explain spatial, temporal, and interspecific variation in the risk of nest predation lack clearly defined mechanisms. I suggest that future studies explicitly define the mechanism and assumption(s) of each hypothesis prior to implementing empirical tests.I found that the discrepancy in results among past studies that have examined the nest-concealment hypothesis was due to interspecific differences in a variety of intrinsic and extrinsic factors that affect nest predation but have previously been ignored. The effects of nest concealment on nest placement and probability of nest predation vary among species and this variation is predictable based on the bird's morphological traits and characteristics of the ecosystem.Increased risk of nest predation early in the breeding season appears to be due, in part, to foliage phenology and spatial and temporal changes in predator behavior. The risk of nest predation was negatively associated with foliage density early, but not late, in the breeding season. Supplemental food provided to nest predators resulted in a numerical response by nest predators, increasing the risk of nest predation at nests located near feeders. I show that intra-seasonal changes in environmental features and predator behavior affect patterns of nest predation, which can influence timing of breeding.

Global environmental changes, especially land-use changes, have profound effects on both ecosystem functioning and biodiversity, having already altered many ecosystem services. These losses emphasize the need to preserve what remains; however when conservation programs are not sufficient, restoring areas that have been destroyed or disturbed can improve conservation efforts and mitigate damages. This work focuses on campos rupestres, Neotropical grasslands found at altitudes, which are part of the Cerrado (Brazilian savannas). They host a great biodiversity with a high level of endemism and, like other mountain ecosystems, provide valuable ecosystem services, such as water purification and recreational services. They have been and still are being impacted by human activities, such as civil engineering construction, quarrying or mining. The first objective of this thesis was to describe the reference ecosystem in order to aim for a clear restoration target and to monitor progress and success. We show that campos rupestres are composed of at least two distinct plant communities (i.e. sandy and stony grasslands), each having a specific composition and structure, hosting a great biodiversity. Several phenological patterns occur among the herbaceous communities: the majority of species flowers and fruits appear during the rainy season but other patterns can be observed. During our 2-year survey, some dominant species belonging to Poaceae, among others, were not observed reproducing, which implies limited chances to disperse on degraded areas. Campo rupestre vegetation is not resilient following a strong disturbance: several years after the disturbance, almost no native species are encountered on the degraded areas, soils are completely altered and seed bank recomposes only with non-target ruderal species. According to the filter model, a local community is a subset of the regional species pool determined by a set of dispersal, abiotic and biotic filters. Acting on the different filters to influence the plant community was the core of our restoration interventions. We then applied three in-situ restoration protocols (hay transfer, species translocation and turf translocation) to restore both kinds of grassland. Hay transfer does not allow the restoration of campo rupestre vegetation because of soil alteration and mainly because of poor seed quality. Indeed, germination studies show that, while some Xyridaceae and Velloziaceae have a high germinability, some dominant Poaceae, Cyperaceae or Asteraceae species have embryoless, unviable or dormant seeds, which makes seeding less efficient. There is no evidence that fire-related cues enhance germination in campos rupestres. Species translocation is successful for only one species, Paspalum erianthum; for the others, root damages probably impede survival. Finally, turf translocation is the most successful method, since numerous species are re-introduced on degraded areas. However due to the low resilience of pristine campos rupestres where turfs are taken from, turf translocation can only be considered in the case of habitat rescue, in circumstances when complete habitat destruction is otherwise unavoidable. Face to the difficulty to restore these peculiar grasslands, the protection and the conservation of campos rupestres must be made a high priority

Mestrado em Engenharia Florestal e dos Recursos Naturais / Instituto Superior de Agronomia. Universidade de Lisboa
Climate change is affecting plant and animal composition in forest ecosystems. Understanding how trees and insects are coping with climate change is most relevant to develop sustainable forest plantations, in the future. Using two REINFFORCE network arboretums, we aimed to analyse how different species and provenances are affected by abiotic and biotic damaging. Additionally, we also aimed to assess phenology influence on herbivory, having as model two Oak species, a native and an exotic, as well as their provenances. In general, there were significant differences in survivorship from different species. However, it did not differ between coniferous and broadleaved species (p = 0.659). It differed at genus level, such as Pinus, where we observed a higher survivorship on natives when compared to exotics. This relation was not verified in oak species. Discolouration was the main damage type verified in some species, in particular on Carob tree, Ceratonia siliqua, which suggests the presence of abiotic stressors, possibly linked to climate conditions and soil. Defoliation values were higher in two broadleaved genera, Quercus and Fagus. Lisbon arboretum had higher damaging and pests than Sintra arboretum, which might be related with the climate differences on both sites and also, the physiological and vegetative status of trees, which presented higher stamina in Sintra. Overall, herbivore damaging was lesser in exotic species than native ones. In herbivory assessment from the two studied Oak species, along Spring season, it was shown that the native species Quercus robur suffered three times more damage, than the exotic species Quercus rubra. Additionally, we showed that herbivore damaging was directly related to phenology development from provenances, thus proving this factor influence
N/A

Large areas of the world’s oceans experience a significant seasonal cycle in phytoplankton biomass. Variability in the phenology of these phytoplankton blooms affect ecosystem dynamics with implications for carbon export production and food availability at higher trophic levels. Climate change is expected to alter phytoplankton seasonality through changes to the underlying physical drivers controlling bloom timing. This thesis focusses on the drivers of contemporary variability and climate change-driven trends in phytoplankton phenology. Satellite-derived chlorophyll data (GlobColour) are used to examine phenological characteristics on a global scale. This dataset is complimented by remotely sensed photosynthetically active radiation (PAR; MODIS), net heat flux (remotely sensed and reanalysis products) and Argo float-derived mixed layer depth datasets in addition to global biogeochemical model output. Four bloom timing metrics are developed to quantify the timing of bloom initiation and termination in a consistent manner. The advantages and limitations of each metric are discussed in the context of the required criteria for a suitable metric definition. The choice of metric definition is based on the performance of the metrics against these criteria. The impact of missing data in the time series on the accuracy of the bloom timing metrics is investigated using the global biogeochemical model NOBM. It is found that missing data cause errors of approximately 30, 15 and 50 days in the date of bloom initiation, peak and termination respectively. The exact cause and implications for phenological studies of these errors is discussed. The physical drivers of interannual variability are examined using global datasets of mixed layer depth, net heat flux and mean mixed layer PAR. The date the net heat flux becomes positive is seen to be a strong predictor for the onset of the subpolar spring bloom, especially in the North Atlantic. This finding is the first to support the critical turbulence hypothesis over Sverdrup’s critical depth theory using satellite observations on a global scale. Physical drivers are only weakly related to interannual variability in bloom timing in the subtropics. The reasons for these relationships and other potential drivers of bloom timing are discussed. Finally, the climate change-driven trends in phytoplankton phenology are investigated using a suite of global biogeochemical models. The ability of the models to capture contemporary seasonality is discussed. The climate change response is found to be strongest at higher latitudes and the phenological changes are consistent with longer periods of strong stratification and earlier onset of ocean warming. Furthermore, it is found that using higher temporal resolution may enable the earlier detection of climate change-driven trends but only at high latitudes.

Smooth brome (Bromus inermis) invasion into tallgrass prairie has led to development of methods of control. Prescribed burning is used by the US Fish and Wildlife Service (USFWS) to manage prairie according to a provisional model developed by Willson and Stubbendieck (2000). The model recommends conducting a prescribed burn at the onset of elongation of smooth brome. The USFWS uses the 5-leaf stage as a phenological cue, signaling the initiation of elongation. Variability in smooth brome development limits the reliability of this method. Our objective was to develop an alternative method to determine when smooth brome populations reach the targeted 50% elongation by correlating accumulated growing degree days and population level plant phenological stages (mean stage count) throughout sites in North Dakota, South Dakota, and Minnesota. A linear regression model was used to determine the onset of elongation in the smooth brome population, regardless of leaf stage variation. Field and greenhouse studies confirmed accumulated growing degree days predicted the initiation of elongation. We also compared smooth brome response to different seasonal burn treatments, determining it could be decreased by burning at other times. As part of the USFWS Native Prairie Adaptive Management program, results will be used to assist management decisions regarding the timing of control.
United States Fish & Wildlife Service
North Dakota State University (NDSU)

Thesis (Ph. D.)--University of California, Riverside, 2009.
Includes abstract. Title from first page of PDF file (viewed Febrary 1, 2010). Includes bibliographical references (p. 140-143). Issued in print and online. Available via ProQuest Digital Dissertations.

To determine growth and development patterns of irrigated melon (Cucumis melo L.) plants as a function of heat units accumulated after planting (HUAP), as well as to develop a general irrigated cantaloupe plant development model as a function of HUAP. Fifteen commercial melon fields managed by cooperator-growers were selected at five locations in Arizona from 2003 through 2006 to conduct phenological monitoring studies. Basic plant growth and development measurements were collected at phenological stages that corresponded to pre-bloom, early fruit set, early netting, and physiological maturity. Results indicate that in general, growth and development stages of melons occurred with a high degree of consistency as function of HUAP in all sites. Varietal differences did not appear to have large effects on phenological development. Also, a general irrigated cantaloupe plant development model as function of HUAP for all sites and varieties was obtained. The purpose of this phenological baseline or model is to assist growers in predicting and identifying critical stages of growth for crop management purposes. Early bloom occurred at 357 ± 41 HUAP; early fruit set at 619 ± 81 HUAP; early netting at 820 ± 82 HUAP; and physiological maturity (of primary fruit set or crown fruit) was identified to occur at 1297 ± 128 HUAP.

Composition, phenology and restoration of campo rupestre mountain grasslands - Brazil. Global environmental changes, especially land-use changes, have profound effects on both ecosystem functioning and biodiversity, having already altered many ecosystem services. These losses emphasize the need to preserve what remains; however when conservation programs are not sufficient, restoring areas that have been destroyed or disturbed can improve conservation efforts and mitigate damages. This work focuses on campos rupestres, Neotropical grasslands found at altitudes, which are part of the Cerrado (Brazilian savannas). They host a great biodiversity with a high level of endemism and, like other mountain ecosystems, provide valuable ecosystem services, such as water purification and recreational services. They have been and still are being impacted by human activities, such as civil engineering construction, quarrying or mining. The first objective of this thesis was to describe the reference ecosystem in order to aim for a clear restoration target and to monitor progress and success. We show that campos rupestres are composed of at least two distinct plant communities (i.e. sandy and stony grasslands), each having a specific composition and structure, hosting a great biodiversity. Several phenolo gical patterns occur among the herbaceous communities: the majority of species flowers and fruits appear during the rainy season but other patterns can be observed. During our 2-year survey, some dominant species belonging to Poaceae, among others, were not observed reproducing, which implies limited chances to disperse on degraded areas. Campo rupestre vegetation is not resilient following a strong disturbance: several years after the disturbance, almost no native species are encountered on the degraded areas, soils are completely altered and seed bank recomposes only with non-target ruderal species. According to the filter model, a local community is a subset of the regional species pool determined by a set of dispersal, abiotic and biotic filters. Acting on the different filters to influence the plant community was the core of our restoration interventions. We then applied three in-situ restoration protocols (hay transfer, species translocation and turf translocation) to restore both kinds of grassland. Hay transfer does not allow the restoration of campo rupestre vegetation because of soil alteration and mainly because of poor seed quality. Indeed, germination studies show that, while some Xyridaceae and Velloziaceae have a high germinability, some dominant Poaceae, Cyperaceae or Asteraceae species have embryoless, unviable or dormant seeds, which makes seeding less efficient. There is no evidence that fire-related cues enhance germination in campos rupestres. Species translocation is successful for only one species, Paspalum erianthum; for the others, root damages probably impede survival. Finally, turf translocation is the most successful method, since numerous species are re -introduced on degraded areas. However due to the low resilience of pristine campos rupestres where turfs are taken from, turf translocation can only be considered in the case of habitat rescue, in circumstances when complete habitat destruction is otherwise unavoidable. Face to the difficulty to restore these peculiar grasslands, the protection and the conservation of campos rupestres must be made a high priority.
Composição, fenologia e restauração dos campos rupestres Brasil. As mudanças ambientais globais, principalmente as mudanças de uso da terra, afetam profundamente o funcionamento dos ecossistemas e a biodiversidade e já alteraram muitos serviços ecossistêmicos. Essas perdas enfatizam a necessidade de se preservar ecossistemas intocados; no entanto, quando os programas de conservação não são suficientes, a restauração das áreas que foram destruídas ou perturbadas pode melhorar os esforços de conservação e mitigar os danos. Este trabalho trata dos campos rupestres, campos neotropicais encontrados em altitudes, incluídos no Cerrado, que possuem uma grande biodiversidade com um alto grau de endemismo e, assim como outros ecossistemas de montanhas, fornecem serviços ecossistêmicos valiosos, tais como filtragem da água e áreas de lazer. Eles foram e ainda estão sendo impactados por atividades humanas, tais como obras de engenharia civil, pedreiras e minas. O primeiro objetivo do presente trabalho foi descrever o ecossistema de referência, a fim de definir claramente um objetivo de restauração para monitorar o progresso e o sucesso da restauração. Mostramos que campos rupestres são compostos por pelo menos duas comunidades vegetais distintas (campos arenoso e pedregoso), cada uma com composição e estrutura específicas e apresentando grande biodiversida de. Vários padrões fenológicos ocorrem nas comunidades herbáceas de campos rupestres: a maioria das espécies florescem e frutificam durante a estação chuvosa, quando algumas espécies reproduzem durante a estação seca mas outros padrões podem ser observados. Durante o nosso levantantamento fenológico de 2 anos, algumas espécies dominantes de Poaceae, entre outros, não foram observadas reproduzindo, o que implica possibilidades limitadas de dispersão em áreas degradadas. A vegetação de campos rupestres não é resiliente após um grande distúrbio: vários anos depois do distúrbio, espécies nativas quase não são encontradas em áreas degradadas, os solos estão completamente alterados e os bancos de sementes recompõem apenas espécies ruderais. De acordo com o modelo dos filtros, uma comunidade local é o resultado de um conjunto regional de espécies selecionadas por três filtros: um filtro de dispersão, um filtro abiótico e um filtro biótico. A atuação sobre os diferentes filtros para influenciar a comunidade de planta s foi o núcleo de nossas intervenções de restauração. Aplicamos, então, três protocolos de restauração in-situ (a transferência de feno, a translocação de espécies e translocação do placa de vegetação) para restaurar os dois tipos de campos. A transferência de feno não permite a restauração da vegetação de campos rupestres devido à alteração do solo e, principalmente, por causa da baixa qualidade das sementes. De fato, estudos mostram que algumas Xyridaceae e Velloziaceae têm uma germinação alta, enquanto algumas espécies dominantes, como Poaceae, Cyperaceae ou Asteraceae, têm sementes sem embrião, inviáveis ou dormentes, o que torna a semeadura uma técnica pouca eficiente. Não há evidências de que o fogo aumenta a germinação das espécies de campos rupestres . A translocação de espécies foi bem sucedida para apenas uma espécie, Paspalum erianthum; para as outras, danos nas raizes provavelmente impediram a sobrevivência. A translocação de placa de vegetação finalmente foi o método mais bem sucedido, uma vez que numerosas espécies foram reintroduzidas em áreas degradadas. No entanto, devido à baixa resiliência dos campos rupestres de onde as placas foram retiradas, a translocação de placa de vegetação apenas pode ser considerada no caso de resgate de habitat, em circunstâncias em que a destruição completa do habitat é inevitável. Face à dificuldade de se restaurar os campos rupestres, a proteção e a conservação dos mesmos deve ser uma prioridade.

La production primaire (PP) dans l'Océan Austral joue un rôle crucial dans la capacité des océans à absorber le carbon atmosphérique. Elle est caractérisée par une forte limitation en Fer et par un cycle saisonnier très marqué, présentant un bloom planctonique en fin d'hiver, plus ou moins intense selon les régions. Ma thèse est centrée sur la compréhension des mécanismes qui contrôlent ce bloom et sa variabilité, ainsi que sur les éléments, présents et futurs, qui contrôlent son intensité. J'ai abordé le premier aspect (phénologie et mécanismes) en mettant en place une approche mécaniste basée sur une nouvelle configuration du modèle biogéochimique PISCES forcé par un environnement physique 1D idéalisé. Cette méthodologie m'a permis de réconcilier les différentes théories sur la formation des blooms aux hautes-latitudes, d'identifier les spécificités du bloom de l'Océan Austral et de proposer des critères adaptés à sa détection dans les observations. En outre, les résultats de cette étude de modélisation ont été confrontés à ceux issues d'une deuxième approche, basée sur des observations satellitaires, ce qui a permis la localisation géographique des différentes phénologies de bloom que j'ai identifiées dans l'Océan Austral. Pour répondre au deuxième aspect (altération et changements futurs), j'ai également suivi une double approche. J'ai d'abord examiné comment les limitations par la lumière et par le fer se combinent, via la variabilité du cycle saisonnier du mélange vertical, et pilotent ainsi la production primaire dans l'Océan Austral actuel à l'aide de la configuration idéalisée présentée plus haut. Dans un deuxième temps, cette analyse a permis d'aider à l’interprétation des variations de PP observées dans les projections climatiques issues de 8 modèles couplés (CMIP5). L'ensemble de mes résultats permet de mieux comprendre les processus physiques et biologiques qui contrôlent la croissance du phytoplancton dans l'Océan Austral et d'appréhender comment la modification de ces processus peut entraîner des altérations de la PP dans une région clé pour l'évolution future du climat
Primary production (PP) in the Southern Ocean (SO) plays a crucial role on atmospheric carbon uptake. PP in this ocean is highly iron-limited and presents a marked seasonal cycle. Such a seasonal cycle has a strong productive phase in late winter, called bloom, which distribution and intensity is highly variable. My PhD focus on two specific aspects of the PP in the SO: first, the mechanisms that drive such a bloom and its dynamics and, second, the elements able to control the bloom intensity at present and in the future. The first aspect (bloom phenology and mechanisms) was addressed by setting up a mechanistic approach based on a novel model configuration: a complex biogeochemical model (PISCES) forced by a 1D idealised physical framework. This methodology allowed me to conciliate the different bloom formation theories and to identify the SO bloom specificities. Moreover, I proposed how to use different bloom detection criteria to properly identify bloom from observations. Such criteria were then tested in a complementary observation-based approach (with satellite and in-situ data) to characterise different bloom phenologies and its spatial distribution in the SO. The second aspect (bloom intensity and future change) was also addressed by a twofold approach. First, using the 1D model, I studied how seasonal variability of vertical mixing combine light and Fe limitation to drive PP. Secondly, I used such an analysis to interpret PP trends observed in 8 coupled model climatic projections (CMIP5 models). My PhD thesis results allow for a better understanding of the physical and biological processes controlling phytoplankton growth. My conclusions also suggest how an alteration of these processes by Climate Change may influence PP in the whole SO, a key region for future climate evolution

La production primaire (PP) dans l'Océan Austral joue un rôle crucial dans la capacité des océans à absorber le carbon atmosphérique. Elle est caractérisée par une forte limitation en Fer et par un cycle saisonnier très marqué, présentant un bloom planctonique en fin d'hiver, plus ou moins intense selon les régions. Ma thèse est centrée sur la compréhension des mécanismes qui contrôlent ce bloom et sa variabilité, ainsi que sur les éléments, présents et futurs, qui contrôlent son intensité. J'ai abordé le premier aspect (phénologie et mécanismes) en mettant en place une approche mécaniste basée sur une nouvelle configuration du modèle biogéochimique PISCES forcé par un environnement physique 1D idéalisé. Cette méthodologie m'a permis de réconcilier les différentes théories sur la formation des blooms aux hautes-latitudes, d'identifier les spécificités du bloom de l'Océan Austral et de proposer des critères adaptés à sa détection dans les observations. En outre, les résultats de cette étude de modélisation ont été confrontés à ceux issues d'une deuxième approche, basée sur des observations satellitaires, ce qui a permis la localisation géographique des différentes phénologies de bloom que j'ai identifiées dans l'Océan Austral. Pour répondre au deuxième aspect (altération et changements futurs), j'ai également suivi une double approche. J'ai d'abord examiné comment les limitations par la lumière et par le fer se combinent, via la variabilité du cycle saisonnier du mélange vertical, et pilotent ainsi la production primaire dans l'Océan Austral actuel à l'aide de la configuration idéalisée présentée plus haut. Dans un deuxième temps, cette analyse a permis d'aider à l’interprétation des variations de PP observées dans les projections climatiques issues de 8 modèles couplés (CMIP5). L'ensemble de mes résultats permet de mieux comprendre les processus physiques et biologiques qui contrôlent la croissance du phytoplancton dans l'Océan Austral et d'appréhender comment la modification de ces processus peut entraîner des altérations de la PP dans une région clé pour l'évolution future du climat
Primary production (PP) in the Southern Ocean (SO) plays a crucial role on atmospheric carbon uptake. PP in this ocean is highly iron-limited and presents a marked seasonal cycle. Such a seasonal cycle has a strong productive phase in late winter, called bloom, which distribution and intensity is highly variable. My PhD focus on two specific aspects of the PP in the SO: first, the mechanisms that drive such a bloom and its dynamics and, second, the elements able to control the bloom intensity at present and in the future. The first aspect (bloom phenology and mechanisms) was addressed by setting up a mechanistic approach based on a novel model configuration: a complex biogeochemical model (PISCES) forced by a 1D idealised physical framework. This methodology allowed me to conciliate the different bloom formation theories and to identify the SO bloom specificities. Moreover, I proposed how to use different bloom detection criteria to properly identify bloom from observations. Such criteria were then tested in a complementary observation-based approach (with satellite and in-situ data) to characterise different bloom phenologies and its spatial distribution in the SO. The second aspect (bloom intensity and future change) was also addressed by a twofold approach. First, using the 1D model, I studied how seasonal variability of vertical mixing combine light and Fe limitation to drive PP. Secondly, I used such an analysis to interpret PP trends observed in 8 coupled model climatic projections (CMIP5 models). My PhD thesis results allow for a better understanding of the physical and biological processes controlling phytoplankton growth. My conclusions also suggest how an alteration of these processes by Climate Change may influence PP in the whole SO, a key region for future climate evolution

Changes in phenology are often cited as a key biotic impact of climate change. Consequently, understanding the major environmental cues and responses to those cues in different species is important for making predictions about the future impacts and ecological implications of changing phenology. In this thesis, I set out to explore the phenological cues, mechanisms of response to temperature and the potential for interacting species to experience phenological mismatch in a range of UK plants. To do this, I utilised phenological records from two citizen science schemes; the well-established Nature’s Calendar, which collects observations for the UK Phenology Network (UKPN), and Track a Tree, a novel project I set up specifically to examine the phenology of interacting plant species in UK woodlands. I first assessed the ability of plasticity to track shifts in the optimum phenology for 22 plant species. I employed a statistical approach to estimate the plasticity and temperature sensitivity of the phenological optimum for leafing and flowering dates obtained from the UKPN. In identifying the most important cues I found that all species are sensitive to spring forcing temperatures, with plastic responses ranging from -3 to -8 days °C-1. Chilling temperatures in autumn/winter and photoperiod were important in species with early and late phenology, respectively. In seven species, plasticity was sufficient to track geographic variation in the optimum phenology. In four species, plasticity did not track the optimum, which is consistent with clinal local adaptation to temperature, and which could place phenology under directional selection in a changing climate. I then performed a phylogenetic comparative analysis on the median phenology and estimates of plasticity and local adaptation for the 22 species analysed previously. I found that phenological event (leafing or flowering) and growth form (woody or herbaceous perennial) predicted plasticity in phenological response. These traits may help inform future predictions of phenological responses to temperature. In contrast, the median date of phenology and clinal local adaptation over latitude were not predicted by any of the ecological traits considered. I next used records from the Track a Tree project to examine the relative phenology of canopy tree and understorey flowering species across UK woodlands. I found that first leafing and peak flowering of focal species pairs were correlated over space, and that the time between canopy leafing and the ground flora flowering (relative phenology) was spatially consistent. Relative phenology of two canopy tree species pairs was spatially consistent, but for a native versus non-native tree species pair the relationship varied over space (with a slope close to 0). If temperature-mediated plasticity determines these species’ phenology, my results suggest understorey flowering may be able to track canopy leafing in future, maintaining shading interactions. Finally, I used the Track a Tree data to partition the variance in phenology for seven tree species, and test what predicts variation in oak and birch. I found that the contributors to variance differ among tree species, with spatial variables important, and within site variance low, for all species except sycamore. The low intraspecific within-site variance suggests that some species may have a limited capacity for phenological buffering. These findings contribute to understanding what impacts on the phenological distribution of different species, an important requirement for assessing the phenological buffering of mismatch. In this thesis, I broadened the range of approaches that can be used to understand plant phenology in a changing climate. I demonstrated the value of employing novel statistical methods to analyse existing phenology data and the utility of hypothesis driven citizen science for predicting phenological shifts and the subsequent ecological implications for interacting species.

Die Länge der Vegetationsperiode (VP) spielt eine zentrale Rolle für die interannuelle Variation der Kohlenstoffspeicherung terrestrischer Ökosysteme. Die Analyse von Beobachtungsdaten hat gezeigt, dass sich die VP in den letzten Jahrzehnten in den nördlichen Breiten verlängert hat. Dieses Phänomen wurde oft im Zusammenhang mit der globalen Erwärmung diskutiert, da die Phänologie von der Temperatur beeinflusst wird.

Die Analyse der Pflanzenphänologie in Süddeutschland im 20. Jahrhundert zeigte:
- Die starke Verfrühung der Frühjahrsphasen in dem Jahrzehnt vor 1999 war kein singuläres Ereignis im 20. Jahrhundert. Schon in früheren Dekaden gab es ähnliche Trends. Es konnten Perioden mit unterschiedlichem Trendverhalten identifiziert werden.
- Es gab deutliche Unterschiede in den Trends von frühen und späten Frühjahrsphasen. Die frühen Frühjahrsphasen haben sich stetig verfrüht, mit deutlicher Verfrühung zwischen 1931 und 1948, moderater Verfrühung zwischen 1948 und 1984 und starker Verfrühung zwischen 1984 und 1999. Die späten Frühjahrsphasen hingegen, wechselten ihr Trendverhalten in diesen Perioden von einer Verfrühung zu einer deutlichen Verspätung wieder zu einer starken Verfrühung.

Dieser Unterschied in der Trendentwicklung zwischen frühen und späten Frühjahrsphasen konnte auch für ganz Deutschland in den Perioden 1951 bis 1984 und 1984 bis 1999 beobachtet werden.
Der bestimmende Einfluss der Temperatur auf die Frühjahrsphasen und ihr modifizierender Einfluss auf die Herbstphasen konnte bestätigt werden. Es zeigt sich jedoch, dass
- die Phänologie bestimmende Funktionen der Temperatur nicht mit einem globalen jährlichen CO2 Signal korreliert waren, welches als Index für die globale Erwärmung verwendet wurde
- ein Index für grossräumige regionale Zirkulationsmuster (NAO-Index) nur zu einem kleinen Teil die beobachtete phänologischen Variabilität erklären konnte.

Das beobachtete unterschiedliche Trendverhalten zwischen frühen und späten Frühjahrsphasen konnte auf die unterschiedliche Entwicklung von März- und Apriltemperaturen zurückgeführt werden. Während sich die Märztemperaturen im Laufe des 20. Jahrhunderts mit einer zunehmenden Variabilität in den letzten 50 Jahren stetig erhöht haben, haben sich die Apriltemperaturen zwischen dem Ende der 1940er und Mitte der 1980er merklich abgekühlt und dann wieder deutlich erwärmt.
Es wurde geschlussfolgert, dass die Verfrühungen in der Frühjahrsphänologie in den letzten Dekaden Teile multi-dekadischer Fluktuationen sind, welche sich nach Spezies und relevanter saisonaler Temperatur unterscheiden. Aufgrund dieser Fluktuationen konnte kein Zusammenhang mit einem globalen Erwärmungsignal gefunden werden.
Im Durchschnitt haben sich alle betrachteten Frühjahrsphasen zwischen 1951 und 1999 in Naturräumen in Deutschland zwischen 5 und 20 Tagen verfrüht. Ein starker Unterschied in der Verfrühung zwischen frühen und späten Frühjahrsphasen liegt an deren erwähntem unterschiedlichen Verhalten. Die Blattverfärbung hat sich zwischen 1951 und 1999 für alle Spezies verspätet, aber nach 1984 im Durchschnitt verfrüht. Die VP hat sich in Deutschland zwischen 1951 und 1999 um ca. 10 Tage verlängert.
Es ist hauptsächlich die Änderung in den Frühjahrphasen, die zu einer Änderung in der potentiell absorbierten Strahlung (PAS) führt. Darüber hinaus sind es die späten Frühjahrsphasen, die pro Tag Verfrühung stärker profitieren, da die zusätzlichen Tage länger undwärmer sind als dies für die frühen Phasen der Fall ist. Um die relative Änderung in PAS im Vergleich der Spezies abzuschätzen, müssen allerdings auch die Veränderungen in den Herbstphasen berücksichtigt werden.
Der deutliche Unterschied zwischen frühen und späten Frühjahrsphasen konnte durch die Anwendung einer neuen Methode zur Konstruktion von Zeitreihen herausgearbeitet werden. Der neue methodische Ansatz erlaubte die Ableitung verlässlicher 100-jähriger Zeitreihen und die Konstruktion von lokalen kombinierten Zeitreihen, welche die Datenverfügbarkeit für die Modellentwicklung erhöhten.
Ausser analysierten Protokollierungsfehlern wurden mikroklimatische, genetische und Beobachtereinflüsse als Quellen von Unsicherheit in phänologischen Daten identifiziert. Phänologischen Beobachtungen eines Ortes können schätzungsweise 24 Tage um das parametrische Mittel schwanken.Dies unterstützt die 30-Tage Regel für die Detektion von Ausreissern.
Neue Phänologiemodelle, die den Blattaustrieb aus täglichen Temperaturreihen simulieren, wurden entwickelt. Diese Modelle basieren auf einfachen Interaktionen zwischen aktivierenden und hemmenden Substanzen, welche die Entwicklungsstadien einer Pflanze bestimmen. Im Allgemeinen konnten die neuen Modelle die Beobachtungsdaten besser simulieren als die klassischen Modelle.

Weitere Hauptresultate waren:
- Der Bias der klassischen Modelle, d.h. Überschätzung von frühen und Unterschätzung von späten Beobachtungen, konnte reduziert, aber nicht vollständig eliminiert werden.
- Die besten Modellvarianten für verschiedene Spezies wiesen darauf hin, dass für die späten Frühjahrsphasen die Tageslänge eine wichtigere Rolle spielt als für die frühen Phasen.
- Die Vernalisation spielte gegenüber den Temperaturen kurz vor dem Blattaustrieb nur eine untergeordnete Rolle.
The length of the vegetation period (VP) plays a central role for the interannual variation of carbon fixation of terrestrial ecosystems. Observational data analysis has indicated that the length of the VP has increased in the last decades in the northern latitudes mainly due to an advancement of bud burst (BB). This phenomenon has been widely discussed in the context of Global Warming because phenology is correlated to temperatures.

Analyzing the patterns of spring phenology over the last century in Southern Germany provided two main findings:
- The strong advancement of spring phases especially in the decade before 1999 is not a singular event in the course of the 20th century. Similar trends were also observed in earlier decades. Distinct periods of varying trend behavior for important spring phases could be distinguished.
- Marked differences in trend behavior between the early and late spring phases were detected. Early spring phases changed as regards the magnitude of their negative trends from strong negative trends between 1931 and 1948 to moderate negative trends between 1948 and 1984 and back to strong negative trends between 1984 and 1999. Late spring phases showed a different behavior. Negative trends between 1931 and 1948 are followed by marked positive trends between 1948 and 1984 and then strong negative trends between 1984 and 1999.
This marked difference in trend development between early and late spring phases was also found all over Germany for the two periods 1951 to 1984 and 1984 to 1999.

The dominating influence of temperature on spring phenology and its modifying effect on autumn phenology was confirmed in this thesis. However,
- temperature functions determining spring phenology were not significantly correlated with a global annual CO2 signal which was taken as a proxy for a Global Warming pattern.
- an index for large scale regional circulation patterns (NAO index) could only to a small part explain the observed phenological variability in spring.

The observed different trend behavior of early and late spring phases is explained by the differing behavior of mean March and April temperatures. Mean March temperatures have increased on average over the 20th century accompanied by an increasing variation in the last 50 years. April temperatures, however, decreased between the end of the 1940s and the mid-1980s, followed by a marked warming after the mid-1980s.
It can be concluded that the advancement of spring phenology in recent decades are part of multi-decadal fluctuations over the 20th century that vary with the species and the relevant seasonal temperatures. Because of these fluctuations a correlation with an observed Global Warming signal could not be found.
On average all investigated spring phases advanced between 5 and 20 days between 1951 and 1999 for all Natural Regions in Germany. A marked difference be! tween late and early spring phases is due to the above mentioned differing behavior before and after the mid-1980s. Leaf coloring (LC) was delayed between 1951 and 1984 for all tree species. However, after 1984 LC was advanced. Length of the VP increased between 1951 and 1999 for all considered tree species by an average of ten days throughout Germany.
It is predominately the change in spring phases which contributes to a change in the potentially absorbed radiation. Additionally, it is the late spring species that are relatively more favored by an advanced BB because they can additionally exploit longer days and higher temperatures per day advancement. To assess the relative change in potentially absorbed radiation among species, changes in both spring and autumn phenology have to be considered as well as where these changes are located in the year.
For the detection of the marked difference between early and late spring phenology a new time series construction method was developed. This method allowed the derivation of reliable time series that spanned over 100 years and the construction of locally combined time series increasing the available data for model development.
Apart from analyzed protocolling errors, microclimatic site influences, genetic variation and the observers were identified as sources of uncertainty of phenological observational data. It was concluded that 99% of all phenological observations at a certain site will vary within approximately 24 days around the parametric mean. This supports to the proposed 30-day rule to detect outliers.
New phenology models that predict local BB from daily temperature time series were developed. These models were based on simple interactions between inhibitory and promotory agents that are assumed to control the developmental status of a plant. Apart from the fact that, in general, the new models fitted and predicted the observations better than classical models, the main modeling results were:
- The bias of the classical models, i.e. overestimation of early observations and underestimation of late observations, could be reduced but not completely removed.
- The different favored model structures for each species indicated that for the late spring phases photoperiod played a more dominant role than for early spring phases.
- Chilling only plays a subordinate role for spring BB compared to temperatures directly preceding BB.

The usefulness of interspecific crosses between Sitka spruce (Picea sitchensis (Bong.) Carr.) and interior spruce (Picea glauca (Moench) Voss, Picea engelmannii Parry and their hybrids) was investigated in one coastal environment. For height growth and bud set most of the variation was at the regional and individual cross level, but very little variation was at the subregional level. The main genetic effects, male and female, accounted for a majority of the genetic variance and additive genetic effects are interpreted as the main factor in the determination of height growth and bud set. For bud set the maternal source of variation accounted for the majority of the genetic variance and a maternal influence on bud set is suggested. Some specific cross combinations were outstanding in height growth and non-additive genetic factors are considered important in these crosses. For bud break most of the variation was due to the residual error, although regions and crosses were statistically significant sources of variation. The Female*Male term was the most important genetic source of variation although bud break is not considered to have as much genetic variation as height and bud set. Large differences were found in the pattern of cold hardiness in the fall and it is considered that photoperiod plays a much larger role than previously thought, especially for interior spruce. Most of the variation was again at the regional and individual cross level. The intermediate performance of the hybrids suggests an inheritance of cold-hardiness based on additive genetic effects. Recommendations are given in the text for the use of these hybrids as well as the areas in which further research would be desireable.
Forestry, Faculty of
Graduate

Leaf phenology refers to the timing of leaf life cycle events and is essential to our understanding of the earth system as it impacts the terrestrial carbon and water cycles and indirectly global climate through changes in surface roughness and albedo. Traditionally, leaf phenology is described as a response to higher temperatures in spring and lower temperatures in autumn for temperate regions. With the advent of carbon ecosystem models however, we need a better representation of seasonal cycles, one that is able to explain phenology in different areas around the globe, including tropical regions, and has the capacity to predict phenology under future climates. We propose a global phenology model based on the hypothesis that phenology is a strategy through which plants reach optimal carbon assimilation. We fit this 14 parameter model to five years of space borne data of leaf area index using a Bayesian fitting algorithm and we use it to simulate leaf seasonal cycles across the globe. We explain the observed increase in leaf area over the Amazon basin during the dry season through an increase in available direct solar radiation. Seasonal cycles in dry tropical areas are explained by the variation in water availability, while phenology at higher latitudes is driven by changes in temperature and daylength. We explore the hypothesis that phenological traits can be explained at the biome (plant functional group) level and we show that some characteristics can only be explained at the species level due to local factors such as water and nutrient availability. We anticipate that our work can be incorporated into larger earth system models and used to predict future phenological patterns.

Phenology is an integrative science that comprises the study of recurring biological activities or events. In an era of rapidly changing climate, the relationship between the timing of those events and environmental cues such as temperature, snowmelt, water availability, or day length are of particular interest. This article provides an overview of the observer-based plant phenology sampling conducted by the U.S. National Ecological Observatory Network (NEON), the resulting data, and the rationale behind the design. Trained technicians will conduct regular in situ observations of plant phenology at all terrestrial NEON sites for the 30-yr life of the observatory. Standardized and coordinated data across the network of sites can be used to quantify the direction and magnitude of the relationships between phenology and environmental forcings, as well as the degree to which these relationships vary among sites, among species, among phenophases, and through time. Vegetation at NEON sites will also be monitored with tower-based cameras, satellite remote sensing, and annual high-resolution airborne remote sensing. Ground-based measurements can be used to calibrate and improve satellite-derived phenometrics. NEON's phenology monitoring design is complementary to existing phenology research efforts and citizen science initiatives throughout the world and will produce interoperable data. By collocating plant phenology observations with a suite of additional meteorological, biophysical, and ecological measurements (e.g., climate, carbon flux, plant productivity, population dynamics of consumers) at 47 terrestrial sites, the NEON design will enable continental-scale inference about the status, trends, causes, and ecological consequences of phenological change.

Orientadores: Ricardo da Silva Torres, Leonor Patricia Cerdeira Morellato
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação
Made available in DSpace on 2018-08-23T23:56:37Z (GMT). No. of bitstreams: 1 Mariano_GreiceCristina_M.pdf: 1816826 bytes, checksum: cc663b657f48189f61cec85c7549130d (MD5) Previous issue date: 2013
Resumo: As mudanças ambientais tornaram-se uma questão importante na agenda global. Um exemplo representativo desses problemas surge no contexto dos estudos de fenologia. Recentemente, fenologia tem ganho importância como o indicador mais simples e confiável dos efeitos das mudanças climáticas sobre plantas e animais. A escassez ou falta de informações e sistemas de monitoramento em regiões tropicais, em particular, na América do Sul, vêm estimulando diversos centros de pesquisa a desenvolverem trabalhos visando preencher esta lacuna. Um exemplo é o Projeto e-phenology, que é multidisciplinar e combina pesquisas em Ciência da Computação e Fenologia. O principal objetivo do projeto é atacar os problemas práticos e teóricos envolvidos no uso de novas tecnologias para realizar a observação remota da fenologia de plantas e integrar estas informações com os dados de campo. Neste contexto, este trabalho apresenta a especificação e implementação de um banco de dados para gerenciar as informações que devem ser manipuladas pelo Projeto ephenology. A proposta apresentada permite a integração de dados de fenologia coletados a partir de observações no campo, com dados climáticos obtidos de sensores de clima e dados de imagens obtidas por câmeras digitais. Tanto a modelagem quanto a implementação do banco de dados tiveram como base os dados dos estudos de fenologia de plantas realizados pelos biólogos e ecólogos do grupo do Laboratório de Fenologia da UNESP de Rio Claro
Abstract: Environmental changes have become an important issue on the world. A representative example of these problems arises in context of studies of phenology. Recently, phenology has gained importance as the simplest and most reliable indicator of the effects of climate change on plants and animals. The shortage or lack of information and monitoring systems in tropical regions, in particularly in South America, has encouraged many centers to develop researches to fulfill this gap. One example includes the e-phenology project. The e-phenology is a multidisciplinary project that combines research in Computer Science and Phenology. The project's main goal is to attack the practical and theoretical problems involved in using new technologies for monitoring plant phenology remotely and integrating obtained data with on-the-ground observations. In this context, this work presents the specification and implementation of a database to manage the information that should be handled by the e-phenology Project. The proposal allows the integration of phenology data collected from field observations, with climate data obtained from climate sensors and image data obtained by digital cameras. Both the modeling and the implementation of the database were based on studies on plant phenology conducted by biologists and ecologists of the Laboratory of phenology at UNESP of Rio Claro
Mestrado
Ciência da Computação
Mestra em Ciência da Computação

Includes bibliographical references.
To date the peculiarities of the inflorescence structure in the wind-pollinated genus Cliffortia (Rosaceae), has gone unnoticed. In this study stereo microscope examination and sketching of fresh and dried specimens, combined with extensive field observations, were performed on eight species of the genus. In its simplest form the inflorescence is a reduced short shoot, bearing a lateral e-bracteate flower and a potentially viable apical bud. Variations in the basic structure can be in the number of flowers, the mix of the sexes of the flowers and the number and type of short shoots as primary, secondary and tertiary axes. A high incidence of structural plasticity of the inflorescence exists. Structural changes can take place throughout the development of the inflorescence or only at the onset of the vegetative stage. These changes occur in the short shoot(s) constituting the axes of the inflorescence, causing either an increase in the length of the internodes, apical proliferation of the axes or a combination of these two effects. A specific combination of changes is linked to a specific inflorescence type. The vegetative elements of the inflorescence thus modified, are retained as an integral part of the vegetative branching system, instead of being discarded after the shedding of the fruits. Thus the inflorescence disappears without being discarded, while the integration of the inflorescence matrix into the vegetative elements of the plant, has a marked effect on the vegetative branching pattern. In some species the structural changes in the inflorescence are linked to changes in the predominance of one sex over the other over time, so that an individual, initially of the one sex, can become one of the opposite sex by the end of the season. In the past the erroneous interpretation of a single point in the process of a sex change as if it is a permanent state of sexuality, led to the prevalent acceptance of dioecy as the norm for the genus, while in truth, it is monoecy with dichogamy in this genus, as in many other wind-pollinated taxa.

The spreading of the invasive plant Garden Lupine (Lupinus polyphyllus) has become a matter of national importance in Sweden, due to it posing a threat to native plant and pollinator diversity. The effective attraction of bumblebees (Bombus spp.) as pollinators facilitates the production of large numbers of seeds, which are key to the Garden Lupine’s success. Possible self-pollination could also provide a competitive edge for the plant. The objective of this study was to study the relationships between Garden Lupine color morphs, pollinator attraction and seeding. Inflorescences of three color morphs were studied during the flowering period, and bumblebee behavior was observed on the site. After seeding, any produced seeds were collected and analyzed, as well as experimentally germinated to provide insight into their viability. A subset of inflorescences of each color morph was prevented access to pollinators, to study potential self-pollination effects. Bumblebees preferred blue flowers over pink, but no difference in pollination between the color morphs was found. Flower color did not affect seed production or seed morphology. Self-pollinated inflorescences produced fewer seeds than those with access to pollinators, but no difference in seed morphology or germinative success between the pollination methods could be established. The results suggest that seed production and germination are less dependent on pollination than expected. The ability to germinate through self-pollination provides insight into the invasive potential of Garden Lupine, suggesting that further studies are needed to successfully counteract its spread.
Den invasiva växten blomsterlupin (Lupinus polyphyllus) har på senare år blivit en nationell angelägenhet i Sverige, där den hotar mångfalden av inhemska växter och pollinatörer. Blomsterlupinens framgångsrika tilldragning av framförallt humlor (Bombus spp.) som pollinatörer möjliggör det stora antalet frön som den producerar, vilket är nyckeln till dess invasiva etablering. Eventuell förmåga till självpollinering kan också utgöra en konkurrensfördel. Målet med studien var att utforska relationen mellan blomsterlupinens färgmorfer, pollinering samt fröbildning. Blomställningar av tre färgmorfer studerades under blomningsperioden. Humlornas beteende observerades också under perioden vid lupinlokalen. Efter frösättning samlades alla producerade frön upp och analyserades, varefter ett frögroningsexperiment utfördes för att belysa frönas grobarhet. I ett fältexperiment nekades en delmängd av blomställningarna tillgång till pollinatörer, för att studera eventuell självpollinering och dess effekter. Humlorna föredrog blåa blommor före rosa, men ingen skillnad i pollinering mellan färgmorferna kunde fastställas. Blommornas färg hade ingen effekt på fröproduktion eller -morfologi. Självpollinerade blomställningar producerade färre frön överlag än de med tillgång till pollinatörer, men ingen skillnad i frömorfologi eller grobarhet mellan pollineringsmetoderna kunde påvisas. Resultaten antyder att fröproduktion och frögroning hos blomsterlupin är beroende av pollinering i mindre grad än förväntat. Förmågan att gro genom självpollinering belyser blomsterlupinens invasiva potential, och antyder att fler studier behövs för att framgångsrikt motverka dess spridning.