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PHENOLOGY AND FRUIT TRAITS OF ARCHONTOPHOENIX CUNNINGHAMIANA, AN INVASIVE PALM TREE IN THE ATLANTIC FOREST OF BRAZIL

Mengardo, Ana Luisa; Pivello, Vania Regina
Fonte: SOC TROPICAL ECOLOGY, GTOE, ZOOLOGICAL RESEARCH INST & MUSE; BONN Publicador: SOC TROPICAL ECOLOGY, GTOE, ZOOLOGICAL RESEARCH INST & MUSE; BONN
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.04%
The Australian palm Archontophoenix cunninghamiana was introduced into Brazil as an ornamental species, and became a dangerous invader of remnant Atlantic forest patches, demanding urgent management actions that require careful planning. Its fruits are greatly appreciated by generalist birds and its sudden eradication could be as harmful as its permanence in the native community. Our hypothesis was that A. cunninghamiana phenology and fruit traits would have facilitated the invasion process. Hence the aim of the study was to characterize the reproductive phenology of the palm by registering flowering and fruiting events, estimating fruit production, and evaluating fruit nutritional levels. Phenological observations were carried out over 12 months and analyzed statistically. Fruit traits and production were estimated. Pulp nutritional levels were determined by analyzing proteins, lipids, and carbohydrates. Results showed constant flowering and fruiting throughout the year with a weak reproductive seasonality. On average, 3651 fruits were produced per bunch mainly in the summer. Fruit analysis revealed low nutrient contents, especially of proteins and lipids compared with other Brazilian native palm species. We concluded that the abundant fruit production all year round...

Dendrocronologia, fenologia, atividade cambial e qualidade do lenho de árvores de Cedrela odorata L., Cedrela fissilis Vell. e Schizolobium parahyba var. amazonicum Hub. ex Ducke, no estado do Acre, Brasil; Dendrochronology, phenology and cambium activity and quality of the wood trees of Cedrela odorata L., Cedrela fissilis Vell. and Schizolobium parahyba var. amazonicum Hub. ex Ducke, in Acre state, Brazil

Lobão, Moisés Silveira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/05/2011 PT
Relevância na Pesquisa
37.04%
O estado do Acre possui uma vocação eminentemente florestal, devido a alta abundância natural de espécies madeireiras em um ecossistema caracterizado pela biodiversidade de espécies tropicais. Pesquisas em dendrocronologia nessa região tropical indicam que 35-50% das espécies arbóreas formam anéis de crescimento. Neste sentido, a dendrocronologia, método baseado na análise de anéis de crescimento anuais no lenho, torna-se importante ferramenta, fornecendo dados de longos períodos de crescimento e estimativas acuradas da idade das árvores, para o entendimento da dinâmica da floresta e desenvolvimento de sistemas de manejo florestal sustentados. Portanto, o objetivo dessa pesquisa foi o de estudar três espécies arbóreas de ocorrência natural no Acre, verificar a influência da quantidade total e distribuição sazonal de pluviosidade, temperatura e evapotranspiração, e os aspectos fenológicos apresentados por cada espécie, no seu crescimento em diâmetro e na qualidade do lenho produzido. O estudo foi realizado em três diferentes sítios, sendo que na Reserva Experimental Catuaba, havia três diferentes microsítios: floresta primária, borda de floresta e pastagem. Avaliou-se mensalmente o incremento em circunferência do tronco das árvores com dendrômetros e a fenologia com observações visuais das árvores das espécies selecionadas. Foram retiradas amostras de lenho no DAP do tronco para as avaliações dendrocronológicas...

Fenologia de quatro espécies tóxicas de senecio (Asteraceae) na região sul do Rio Grande do Sul; Phenology of four poisonous senecio (Asteraceae) species in southern Rio Grande do Sul, Brazil

Karam, Fernando Sérgio Castilhos; Mendez, Maria del Carmen; Jarenkow, Joao Andre; Riet-Correa, Franklin
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
Relevância na Pesquisa
37.04%
O objetivo principal desse trabalho foi determinar a fenologia de Senecio brasiliensis, S. oxyphyllus, S. heterotrichius e S. selloi, e relacioná-la com a epidemiologia da intoxicação em bovinos, na região sul do Rio Grande do Sul. O estudo fenológico foi feito durante dois anos nos municípios de Bagé e Capão do Leão. As leituras foram mensais durante o período vegetativo e quinzenais no período reprodutivo das espécies, para observação desde sua emergência até dispersão de sementes, avaliando-se o vigor, e relacionando essas variáveis com fatores ambientais. Os resultados permitiram concluir que durante todo o ano há emergência de plantas de Senecio spp, desde que haja condições ambientais favoráveis, como umidade e luz, e as fenofases vegetativas são praticamente constantes durante todo o ciclo da planta. Fatores ambientais desfavoráveis como o déficit hídrico, o manejo do solo e o dano de insetos, associados ou não, podem alterar o ciclo das plantas e serem determinantes para a sua permanência no ambiente. A maioria dos exemplares, das quatro espécies, comportou-se como anual e monocárpica. A espécie mais persistente no ambiente foi S. heterotrichius (15% das plantas persistiram durante os dois anos de estudo)...

Effects of environmental conditions associated to the cardinal orientation on the reproductive phenology of the cerrado savanna tree Xylopia aromatica (Annonaceae)

Camargo, Maria Gabriela G.; Souza, Regina M.; Reys, Paula; Morellato, Leonor P.C.
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: 1007-1020
ENG
Relevância na Pesquisa
37.14%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Processo FAPESP: 05/57740-0; Processo FAPESP: 07/59779-6; O cerrado brasileiro vem sofrendo um processo intenso de fragmentação, que levou ao aumento de remanescentes sujeitos aos efeitos de borda e a alterações nas condições ambientais que podem afetar a fenologia das plantas. O objetivo deste trabalho foi verificar se a fenologia reprodutiva de Xylopia aromatica (Lam.) Mart. (Annonaceae) difere sob diferentes condições de luz em um cerrado sensu stricto no sudeste do Brasil. Comparamos a fenologia reprodutiva de árvores de X. aromatica distribuídas nas faces leste e sul do cerrado, observadas mensalmente de janeiro de 2005 a dezembro de 2008. A face leste apresentou maior incidência de luz, temperaturas e aberturas do dossel em relação à face sul. X. aromatica apresentou reprodução sazonal em ambas as faces do cerrado, mas a porcentagem de indivíduos, sincronia e duração das fenofases foram maiores na face leste. O estudo demonstrou a influência das condições ambientais associadas à orientação cardeal das faces do cerrado no padrão fenológico de X. aromatica. Respostas similares poderão ser observadas em outras espécies de cerrado...

Phenology of Atlantic rain forest trees: A comparative study

Morellato, L. Patricia C.; Talora, Daniela C.; Takahasi, Adriana; Bencke, Cinara C.; Romera, Eliane C.; Zipparro, Valescka B.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 811-823
ENG
Relevância na Pesquisa
37.21%
This paper describes the phenology of leaf, flower, and fruit phenology in the Atlantic rain forests of southeastern Brazil. For 17 months, we observed the phenological patterns of trees from two Atlantic forest types at four sites: premontane forest (Sites I and IV; the typical Atlantic rain forest) and coastal plain forest (Sites II and III). All sites experience a nonseasonal, tropical wet climate, characterized by an annual rainfall usually > 2000 mm and lacking a dry season. We tested for the occurrence (or absence) of seasonal phenological patterns within each site and compared the patterns detected among the four different forest sites using circular statistics. The expected weakly seasonal phenological patterns were not observed for these forests. Flowering and leaf flush patterns of Atlantic rain forest trees were significantly seasonal, concentrated at the beginning of the wettest season, and were significantly correlated with day length and temperature. These results stress the influence that seasonal variation in day length has on ever-wet forest tree phenology. Fruiting phenologies were aseasonal in all four forests. Flowering patterns did not differ significantly among three of the four forest sites analyzed, suggesting the occurrence of a general flowering pattern for Atlantic rain forest trees.

Inter and intraspecific variation on reproductive phenology of the Brazilian Atlantic forest Rubiaceae: Ecology and phylogenetic constraints

San Martin-Gajardo, Ivonne; Morellato, L. Patricia C.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 691-698
ENG
Relevância na Pesquisa
37.21%
The reproductive phenology of seven species of Rubiaceae from the Brazilian Atlantic rain forest was compared to evaluate the occurrence of phylogenetic constraints on flowering and fruiting phenologies. Since phenological patterns can be affected by phylogenetic constraints, we expected that reproductive phenology would be similar among plants within a family or genus, occurring during the same time (or season) of the year. Observations on flowering and fruiting phenology were carried out monthly, from December 1996 to January 1998, at Núcleo Picinguaba, Parque Estadual da Serra do Mar, Ubatuba, São Paulo State, Brazil. Nine phenological variables were calculated to characterize, quantify and compare the reproductive phenology of the Rubiaceae species. The flowering patterns were different among the seven species studied, and the Kruskal-Wallis test indicated significant differences in flowering duration, first flowering, peak flowering and flowering synchrony. The peaks and patterns of fruiting intensity were different among the Rubiaceae species studied and they differed significantly from conspecifics in the phenological variables fruiting duration, fruiting peak date, and fruiting synchrony (Kruskal-Wallis test). Therefore, we found no evidence supporting the phylogenetic hypotheses...

Reproductive phenology of Atlantic forest tree species in Brazil: An eleven year study

Engel, Vera Lex; Martins, Fernando Roberto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1-16
ENG
Relevância na Pesquisa
37.04%
This paper describes the reproductive phenorhythms of tree species in a tropical seasonal lowland forest in Southeastern Brazil. Every two weeks, five individuals of 41 species were observed for the occurrence of flowering and fruiting, from May 1982 to December 1992. All phenophases showed high seasonality, when considering the whole set of species, but the amplitude of the cycles was much more variable between years; only 13 species had regular flowering. Infra-annual flowering and fruiting were found in 11 and four species, respectively, while only one species flowered and fruited continually. Supra-annual cycles were observed in four (flowering) and seven (fruiting) species. An increase was observed in number of species and individuals flowering and fruiting from 1990 to 1992, following mainly an elevation in the absolute minimum air temperature. These data suggest a relationship between reproductive phenology and major climatic phenomena like El Niño events and solar activity cycles. © International Society for Tropical Ecology.

Remote phenology: Applying machine learning to detect phenological patterns in a cerrado savanna

Almeida, Jurandy; Dos Santos, Jefersson A.; Alberton, Bruna; Torres, Ricardo Da S.; Morellato, Leonor Patricia C.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência
ENG
Relevância na Pesquisa
37.04%
Plant phenology has gained importance in the context of global change research, stimulating the development of new technologies for phenological observation. Digital cameras have been successfully used as multi-channel imaging sensors, providing measures of leaf color change information (RGB channels), or leafing phenological changes in plants. We monitored leaf-changing patterns of a cerrado-savanna vegetation by taken daily digital images. We extract RGB channels from digital images and correlated with phenological changes. Our first goals were: (1) to test if the color change information is able to characterize the phenological pattern of a group of species; and (2) to test if individuals from the same functional group may be automatically identified using digital images. In this paper, we present a machine learning approach to detect phenological patterns in the digital images. Our preliminary results indicate that: (1) extreme hours (morning and afternoon) are the best for identifying plant species; and (2) different plant species present a different behavior with respect to the color change information. Based on those results, we suggest that individuals from the same functional group might be identified using digital images...

Applying machine learning based on multiscale classifiers to detect remote phenology patterns in Cerrado savanna trees

Almeida, Jurandy; dos Santos, Jefersson A.; Alberton, Bruna; Torres, Ricardo da S.; Morellato, Leonor Patricia C.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
37.14%
Plant phenology is one of the most reliable indicators of species responses to global climate change, motivating the development of new technologies for phenological monitoring. Digital cameras or near remote systems have been efficiently applied as multi-channel imaging sensors, where leaf color information is extracted from the RGB (Red, Green, and Blue) color channels, and the changes in green levels are used to infer leafing patterns of plant species. In this scenario, texture information is a great ally for image analysis that has been little used in phenology studies. We monitored leaf-changing patterns of Cerrado savanna vegetation by taking daily digital images. We extract RGB channels from the digital images and correlate them with phenological changes. Additionally, we benefit from the inclusion of textural metrics for quantifying spatial heterogeneity. Our first goals are: (1) to test if color change information is able to characterize the phenological pattern of a group of species; (2) to test if the temporal variation in image texture is useful to distinguish plant species; and (3) to test if individuals from the same species may be automatically identified using digital images. In this paper, we present a machine learning approach based on multiscale classifiers to detect phenological patterns in the digital images. Our results indicate that: (1) extreme hours (morning and afternoon) are the best for identifying plant species; (2) different plant species present a different behavior with respect to the color change information; and (3) texture variation along temporal images is promising information for capturing phenological patterns. Based on those results...

Using phenology to assess urban heat islands in tropical and temperate regions

Jochner, Susanne; Alves-Eigenheer, Milene; Menzel, Annette; Morellato, Leonor Patricia C.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 3141-3151
ENG
Relevância na Pesquisa
37.21%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 09/54208-6; The study of urban phenology is relevant to assess the effects of heat islands and the potential impacts of climate change on plants. Temperature is the main factor regulating plant development in moist/temperate regions. However, plants in tropical cities may respond to additional environmental cues, such as air humidity. We examined whether differences in air temperature and humidity along an urban-rural gradient influenced phenological onset dates of trees in a temperate mid-latitude city (Munich, Germany) and a city in the neotropics (Campinas, Brazil). (Dis)similarities were identified incorporating equivalent study design based on identical methods for recording phenology and site-specific meteorological data. We found that phenological onset dates of silver birch (Betula pendula) were able to describe local temperature variations in Munich. Correlation coefficients between mean temperature and onset dates of Betula were significant and varied between r=-0.48 and r=-0.72. However, onset dates for yellow trumpet tree (Tabebuia chrysotricha)...

Effects of environmental conditions associated to the cardinal orientation on the reproductive phenology of the cerrado savanna tree Xylopia aromatica (Annonaceae)

Camargo,Maria Gabriela G.; Souza,Regina M.; Reys,Paula; Morellato,Leonor P.C.
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2011 EN
Relevância na Pesquisa
37.14%
The Brazilian cerrado has undergone an intense process of fragmentation, which leads to an increase in the number of remnants exposed to edge effects and associated changes on environmental conditions that may affect the phenology of plants. This study aimed to verify whether the reproductive phenology of Xylopia aromatica (Lam.) Mart. (Annonaceae) differs under different light conditions in a cerrado sensu stricto (a woody savanna) of southeastern Brazil. We compared the reproductive phenology of X. aromatica trees distributed on east and south cardinal faces of the cerrado during monthly observations, from January 2005 to December 2008. The east face had a higher light incidence, higher temperatures and canopy openness in relation to south face. X. aromatica showed seasonal reproduction at both faces of the cerrado, but the percentage of individuals, the synchrony and duration of phenophases were higher at the east face. The study demonstrated the influence of the environmental conditions associated to the cardinal orientation of the cerrado faces on the phenological pattern of X. aromatica. Similar responses may be observed for other species, ultimately affecting patterns of floral visitation and fruit production, which reinforces the importance of considering the cardinal direction in studies of edge effects and fragmentation.

Standardized phenology monitoring methods to track plant and animal activity for science and resource management applications

Denny, Ellen G.; Gerst, Katharine L.; Miller-Rushing, Abraham J.; Tierney, Geraldine L.; Crimmins, Theresa M.; Enquist, Carolyn A. F.; Guertin, Patricia; Rosemartin, Alyssa H.; Schwartz, Mark D.; Thomas, Kathryn A.; Weltzin, Jake F.
Fonte: Springer Berlin Heidelberg Publicador: Springer Berlin Heidelberg
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
37.14%
Phenology offers critical insights into the responses of species to climate change; shifts in species’ phenologies can result in disruptions to the ecosystem processes and services upon which human livelihood depends. To better detect such shifts, scientists need long-term phenological records covering many taxa and across a broad geographic distribution. To date, phenological observation efforts across the USA have been geographically limited and have used different methods, making comparisons across sites and species difficult. To facilitate coordinated cross-site, cross-species, and geographically extensive phenological monitoring across the nation, the USA National Phenology Network has developed in situ monitoring protocols standardized across taxonomic groups and ecosystem types for terrestrial, freshwater, and marine plant and animal taxa. The protocols include elements that allow enhanced detection and description of phenological responses, including assessment of phenological “status”, or the ability to track presence–absence of a particular phenophase, as well as standards for documenting the degree to which phenological activity is expressed in terms of intensity or abundance. Data collected by this method can be integrated with historical phenology data sets...

Fenologia e comportamento de parasitoidismo de Spalangia endius Walker, 1839 (Hymenoptera, Pteromalidae) em condi????es de laborat??rio; Phenology and parasitoidism behavior of Spalangia endius Walker, 1839 (Hymenoptera, Pteromalidae) under laboratory conditions

Ara??jo, Dani Furtado de
Fonte: Universidade Federal de Pelotas; Biologia; Programa de P??s-gradua????o em Parasitologia; UFPel; BR Publicador: Universidade Federal de Pelotas; Biologia; Programa de P??s-gradua????o em Parasitologia; UFPel; BR
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.21%
Synantropic flies frequently reach the status of plague in urban and rural areas, assuming an important role regarding its vectorial ability and nuisance to men and animals. Therefore, it is necessary to know their natural enemies in order to achieve a satisfactory control of these dipterans. The success of the biological control as an alternative to the Integrated Pest Management depends on the evaluation of enemies as potential control agents through the development of breeding techniques and laboratory evaluations. Considering that, this study had as objective to understand the phenology of Spalangia endius as well as the parasitoidism of this species using M. domestica, Muscina stabulans and Chrysomya megacephala as hosts, being the last two potential alternative hosts. Colonies of S. endius, M. domestica, M. stabulans e C. megacephala were kept in climatized chamber, at 26??C ?? 2, relative air humidity ???70% and 12 hours photophase. In order to know the phenology of S. endius, 360 pupae of Musca domestica with ages ranging from 24 to 48 hours were exposed to 15 couples of S. endius for a period of 48 hours at 26??C ?? 2. These pupae were kept in B.O.D chambers at the same conditions of the climatized chamber, where 15 specimens were dissecated to observe the stage and the development time of the hymenopteran. The phenology allows concluding that S. endius presents a development cycle (egg-adult) of 19 to 31 days...

Detection of QTL for metabolic and agronomic traits in wheat with adjustments for variation at genetic loci that affect plant phenology

Hill, C.B.; Taylor, J.D.; Edwards, J.; Mather, D.; Langridge, P.; Bacic, A.; Roessner, U.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2015 EN
Relevância na Pesquisa
37.14%
Mapping of quantitative trait loci associated with levels of individual metabolites (mQTL) was combined with the mapping of agronomic traits to investigate the genetic basis of variation and co-variation in metabolites, agronomic traits, and plant phenology in a field-grown bread wheat population. Metabolome analysis was performed using liquid chromatography–mass spectrometry resulting in identification of mainly polar compounds, including secondary metabolites. A total of 558 metabolic features were obtained from the flag leaves of 179 doubled haploid lines, of which 197 features were putatively identified, mostly as alkaloids, flavonoids and phenylpropanoids. Coordinated genetic control was observed for several groups of metabolites, such as organic acids influenced by two loci on chromosome 7A. Five major phenology-related loci, which were introduced as cofactors in the analyses, differed in their impact upon metabolic and agronomic traits with QZad-aww-7A having more impact on the expression of both metabolite and agronomic QTL than Ppd-B1, Vrn-A1, Eps, and QZad-aww-7D. This QTL study validates the utility of combining agronomic and metabolomic traits as an approach to identify potential trait enhancement targets for breeding selection and reinforces previous results that demonstrate the importance of including plant phenology in the assessment of useful traits in this wheat mapping population.; Camilla B. Hill...

Female perspectives on breeding phenology in Eastern Ontario Gray Treefrogs

Roberts, Hayley J.
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
37.14%
Studies of the forces that shape local adaptation contribute to our understanding of origins of range-wide variation, speciation, and potential responses to changing environments. Phenology is an important component of such local adaptation. Phenological research is central to studies of geographical range limits and species distributions, migration, speciation, response to climate change and ex situ conservation and re-introduction programs. Despite over 22,000 phenological studies published thus far, there is a lack of phenological information on reproductive patterns of temperate anurans, particularly for females. My thesis therefore focuses on gaining insights into temperate frog phenology primarily of females, and patterns of female choice. I focus on Hyla versicolor (Gray Treefrogs), an Eastern North American temperate frog. My data come from perimeter transect surveys done at two wetlands at the Queen’s University Biological Station over the entire 2014 breeding season. I compared male and female peak abundance using an N-mixture model. Both males and females peaked on Julian Day 154 (June 3rd 2014). Females arrived three days after males in my focal wetlands, and left three days before. Timing of arrival is most likely based on a combination of females responding to male advertisement calls...

Especificação e implementação do banco de dados do projeto e-phenology; Specification and implementation of the database of the e-phenology

Greice Cristina Mariano
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 09/08/2013 PT
Relevância na Pesquisa
37.44%
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.; Environmental changes have become an important issue on the world. A representative example of these problems arises in context of studies of phenology. Recently...

The Effect of Warming on Phenology, Physiology, and Leaf Nitrogen in Six Deciduous Tree Species Over the Growing Season

Stine, Anne Walton
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Tese de Doutorado
Publicado em //2013
Relevância na Pesquisa
37.3%

There is no consensus on climatic warming's effect on phenology, photosynthesis, and leaf nitrogen content in temperate deciduous tree species. A major question is whether or how these trees will utilize a longer growing season. Data on leaf photosynthetic rates, leaf nitrogen content, and leaf phenological status were collected weekly or biweekly in 2012 for Acer rubrum, Liquidambar styraciflua, Liriodendron tulipifera, Quercus alba, Quercus rubra, and Fraxinus americana at Duke Forest in Orange County, North Carolina. Seedlings were grown in open-topped chambers established in 2009 that were maintained at either ambient or 5 degrees Celsius above ambient temperatures. Half the chambers were shaded, half were under gap conditions.

Four of six species had advanced spring phenology with warming treatment, and four of six species delayed leaf senescence with warming treatment. Shade delayed spring phenology later more than earlier in the season, and gap conditions delayed fall phenology. Warming had an inconsistent effect on photosynthetic rate. Two species increased photosynthetic rate with chambered +5C conditions, another decreased photosynthetic rate in unchambered plots. Half of the species studied had no significant correlation between temperature and photosynthetic rate. The timing of photosynthetic decline was simultaneous within species across warming treatments...

A Qualitative Characterization of Spring Vegetation Phenology Using MODIS Imagery for the Piedmont of North Carolina from 2000 to 2007

Bausch, Adam J.
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project Formato: 4418172 bytes; 95437 bytes; application/pdf; application/pdf
EN_US
Relevância na Pesquisa
37.14%
Recent studies have shown vegetation phenology around the world is being altered by increased variability in temperatures associated with a warming climate. The onset of spring and the duration of the growing season in many eastern states has been pushed forward an average of 2-5 days and lengthened by as much as 10-15 days respectively, as a response to climatic forcing. Analyzing phenological changes to forest dynamics is aided by the use of satellite imagery with high temporal and spatial resolution to accurately estimate the timing of recurrent events associated with the flush of green vegetation at the beginning of spring in deciduous forests. This study used daily MODIS images at 250m processed to Normalized Difference in Vegetation Index (NDVI) for the spring greenup from 2000-2003 and 2007. Of the 792 available images, 20 sites along the Piedmont, coastal plain, and mountains of North Carolina were filtered (a lowpass Savitsky-Golay convolution filter) to remove atmospheric noise, and used to estimate relevant phenological parameters. Onset of spring, length of growing season, rate of green-up, as well as, maximum green-up, were identified using a segmented regression technique. Over the study period, the Piedmont sites exhibited high variability in dates of onset among sites ( 5days) and negatively between years (6 days)...

Phenology and recruitment of Caryocar costaricense (Caryocaceae), an endemic tree species of Southern Central America

Solís,Silvia; Lobo,Jorge; Grimaldo,Mayori
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2009 EN
Relevância na Pesquisa
37.14%
Basic aspects of the reproductive biology are largely unknown for most tropical tree species, although they are important elements to understand the impacts of anthropogenic activities as logging and forest fragmentation on these populations. In this study, data are presented on leaf and reproductive phenology, fruit production and seedling demography of a population of an endemic tree species of Southern Central America, Caryocar costaricense. This species has been affected by selective logging and forest fragmentation of its habitat. Phenology was studied by observation of 15-22 tree crowns during two reproductive periods (2003 and 2005). Circular plots were established around 11 adult trees to count the number of fallen fruits and seedlings during three years (2003, 2004, 2005). Although reproductive phenology is restricted to the short dry season in this species, seed germination occurred year-round. Fruit and seedling production shows a strong inter-individual variation within the study populations, with two large trees producing nearly 50%-70% of the fruits and seedlings during two years. Most of the seeds that fall beneath the tree crown are covered by litterfall or removed by fauna. We found evidence that many of these seeds become part of a seed bank in the forest floor. Because of the observed reproductive dominance of few large trees in these populations...

Inter and intraspecific variation on reproductive phenology of the Brazilian Atlantic forest Rubiaceae: ecology and phylogenetic constraints

SanMartin-Gajardo,Ivonne; C. Morellato,L. Patricia
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2003 EN
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The reproductive phenology of seven species of Rubiaceae from the Brazilian Atlantic rain forest was compared to evaluate the occurrence of phylogenetic constraints on flowering and fruiting phenologies. Since phenological patterns can be affected by phylogenetic constraints, we expected that reproductive phenology would be similar among plants within a family or genus, occurring during the same time (or season) of the year. Observations on flowering and fruiting phenology were carried out monthly, from December 1996 to January 1998, at Núcleo Picinguaba, Parque Estadual da Serra do Mar, Ubatuba, São Paulo State, Brazil. Nine phenological variables were calculated to characterize, quantify and compare the reproductive phenology of the Rubiaceae species. The flowering patterns were different among the seven species studied, and the Kruskal-Wallis test indicated significant differences in flowering duration, first flowering, peak flowering and flowering synchrony. The peaks and patterns of fruiting intensity were different among the Rubiaceae species studied and they differed significantly from conspecifics in the phenological variables fruiting duration, fruiting peak date, and fruiting synchrony (Kruskal-Wallis test). Therefore, we found no evidence supporting the phylogenetic hypotheses...