Consulta: subjectFacets:"Population ecology"
Registros recuperados: 15
Data/hora: 11/06/2024 12:18:05

Balloniscus glaber (Crustacea, Isopoda, Balloniscidae), a habitat specialist species in a disturbed area of Brazil
Provedor de dados: Iheringia Série Zoologia
Autores: Kenne,Diego Costa; Araujo,Paula Beatriz.
ABSTRACT Balloniscus glaber Araujo &amp; Zardo, 1995 (Balloniscidae), a Neotropical Oniscidea, has been recorded historically in environments with low or no human interference. In one of these areas, it was determined as aK-strategist. Recently, however, this species was documented in a disturbed forest within urban limits. The present work revealed that the population in the urban area has high density, high number of ovigerous females and mancae in the population, a long reproductive period, and early sexual maturity. These results suggest that modified environments may provide favorable conditions and that the species is not negatively affected by human influence.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Human interference; Anthropogenic influence; Population ecology; K-strategist; Terrestrial isopods.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212015000400430

Uncovering ecological state dynamics with hidden Markov models
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Mcclintock, Brett T.; Langrock, Roland; Gimenez, Olivier; Cam, Emmanuelle; Borchers, David L.; Glennie, Richard; Patterson, Toby A.; Coulson, Tim.
Ecological systems can often be characterised by changes among a finite set of underlying states pertaining to individuals, populations, communities or entire ecosystems through time. Owing to the inherent difficulty of empirical field studies, ecological state dynamics operating at any level of this hierarchy can often be unobservable or ‘hidden’. Ecologists must therefore often contend with incomplete or indirect observations that are somehow related to these underlying processes. By formally disentangling state and observation processes based on simple yet powerful mathematical properties that can be used to describe many ecological phenomena, hidden Markov models (HMMs) can facilitate inferences about complex system state dynamics that might otherwise...
Tipo: Text
Palavras-chave: Behavioural ecology; Community ecology; Ecosystem ecology; Hierarchical model; Movement ecology; Observation error; Population ecology; State-space model; Time series.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00655/76692/77831.pdf

Evaluation of population parameters of coypu Myocastor coypus (Rodentia, Myocastoridae) during and outside the authorised hunting season in the floodplain of the Paraná River, Argentina
Provedor de dados: Mastozoología Neotropical
Autores: Courtalon,Paula; Spina,Florencia; Fernández,Roque; Porini,Gustavo; Bó,Roberto Fabián.
We studied a Myocastor coypus (Molina, 1782) population during the authorised hunting season (AHS) and outside the hunting season (OHS) in the floodplain of the Paraná River (Argentina), a representative area for this species within its original geographic range. The aims of this work were to describe and compare fluctuations in population parameters (relative abundance, sex ratio, age structure) and in the physical condition between these two periods. Additionally, we discussed the possible occurrence of simultaneous influence of environmental factors (particularly the hydroperiod) and hunting pressure on these parameters. The absolute density during the AHS was 2.78 individuals/ha. No differences in the trapping success index were found between AHS and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Argentina; Hunting pressure; Myocastor coypus; Paraná River Delta; Population ecology.
Ano: 2011
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-93832011000200004

Population dynamics, life stage and ecological modeling in Chrysomya albiceps (Wiedemann) (Diptera: Calliphoridae)
Provedor de dados: Neotropical Entomology
Autores: Rosa,GS; Costa,MIS; Corrente,JE; Silveira,LVA; Godoy,WAC.
In this study we investigated the population dynamics of Chrysomya albiceps (Wiedemann) with laboratory experiments, employing survival analysis and stage structure mathematical models, emphasizing survival among life stages. The study also assessed the theoretical influence of density dependence and cannibalism during immature stages, on the population dynamics of the species. The survival curves were similar, indicating that populations of C. albiceps exhibit the same pattern of survival among life stages. A strong nonlinear trend was observed, suggesting density dependence, acting during the first life stages of C. albiceps. The time-series simulations produced chaotic oscillations for all life stages, and the cannibalism did not produce qualitative...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Population ecology; Stage matrix; Blowfly.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2011000200005

Population Dynamics and Spatial Distribution of Spartocera dentiventris (Berg) (Hemiptera: Coreidae) Adults on Nicotiana tabacum L. (Solanaceae)
Provedor de dados: Neotropical Entomology
Autores: JESUS,CRISTIANE R.; REDAELLI,LUIZA R.; ROMANOWSKI,HELENA P.
Spartocera dentiventris (Berg), the gray-tobacco-bug, feeds on the sap of the plant, inducing leaf wilting and twisting, thus causing economic losses to the tobacco crop. The knowledge on its population dynamics is crucial for the development of efficient techniques for monitoring and managing this species. An experimental tobacco (Nicotiana tabacum) crop was established in Porto Alegre County, South Brazil, aiming to study the colonization, establishment, growth and spatial distribution of the adult S. dentiventris population using the mark-release-recapture method. All plants were inspected at least three times a week. From August 1999 to April 2000, 217 individuals were marked. Only one generation completed development up to the adult phase. Population...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Insecta; Population ecology; Mark-release-recapture method.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2002000400006

Population fluctuation, immature mortality and adult longevity of Spartocera dentiventris (Berg) (Hemiptera: Coreidae) on Nicotiana tabacum (Solanaceae)
Provedor de dados: Neotropical Entomology
Autores: Canto-Silva,Celson R.; Romanowski,Helena P.
The population fluctuations, mortality in the immature phases and longevity of the Spartocera dentiventris (Berg) adults were studied in an experimental plot of Nicotiana tabacum (Solanaceae) at the Faculdade de Agronomia - Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil (30º 05' S and 51º 13' W). From November 1996 to March 1997, 30 sampling occasions were carried out: 23 plants were inspected and the number of eggs and nymphs per instar counted and adults marked / recaptured. Mortality in immature bugs was estimated by the difference between the population peaks in successive instars per plants. Parasitism was evaluated based on the egg colour. Two generations developed through the cycle of the crop, the various instars overlapping in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Gray-tobacco-bug; Population ecology; Parasitism.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2003000300003

Ecology of Phallotorynus pankalos (Cyprinodontiformes: Poeciliidae) in a first-order stream of the upper Paraná Basin
Provedor de dados: Neotropical Ichthyology
Autores: Súarez,Yzel R.; Silva,João Paulo da; Vasconcelos,Lilian P.; Antonialli-Júnior,William Fernando.
Some aspects of the population ecology of Phallotorynus pankalos in a first-order stream of the Iguatemi River Basin are described based on samples taken from March/2007 to February/2008. A total of 2680 individuals, including 948 males and 1732 females was collected. Adult females are larger than males; theirs mean fecundity was estimated as 6.5 embryos/female. There was a strong correlation between standard length and ovary weight, relative ovary weight, and number of embryos. The size of the first maturation of 50% of female population was estimated as 18.24 mm of standard lenght. High female mortality was observed after the first reproduction and sex ratio presents seasonal variation with higher female proportion in the winter.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fecundity; Iguatemi River Basin; Population ecology; Reproduction; Stream fish.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000100007

Synchrony is more than overlap: measuring phenological synchronization considering time length and intensity
Provedor de dados: Revista Brasileira de Botânica
Autores: Freitas,Leandro; Bolmgren,Kjell.
The degree of flowering and fruiting synchronization is believed to have ecological and evolutionary relevance at several scales. Here we discuss some measures that have been used to estimate synchrony and propose an index that incorporates both the entire length of an individual phenophase and variation in the number of flowers or fruits over that time period. This new index describes more accurately the phenological synchrony among individuals and populations.
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Fitness; Phenology; Pollination; Population ecology; Seed dispersal.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042008000400017

Population dynamics and reproductive strategy of Scolelepis goodbodyi (Polychaeta: Spionidae) in a subtropical atlantic beach
Provedor de dados: Revista Brasileira de Zoologia
Autores: Leão,Luciana S. Dourado; Soares-Gomes,Abílio; Costa,Tarso; Santos,Cinthya S. Gomes.
The population dynamics and reproductive strategy of the polychaete Scolelepis goodbodyi (Jones, 1962), were investigated between June 2009 and May 2010 at Manguinhos beach, southeastern, Brazil. A total of 9,242 individuals were collected. The density did not differ significantly from one month to another. The estimated values of the growth, recruitment, and mortality rates were studied using the width of the third setiger and the growth curves for the populations were adjusted by the Bhattacharya method (L'= 1.23, K = 1.2, mortality = 0.73). Two annual cohorts were identified in the period. Significant differences between males and females were observed in the population (x² = 71.6, p &lt; 0.01) and between sexually defined and sexually indeterminate...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Annelida; Population ecology; Reproductive biology.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702012000300002

Three years on demography of a group of Alouatta guariba clamitans Cabrera (Primates, Atelidae): growth and fragmentation
Provedor de dados: Zoologia
Autores: Miranda,João M. D.; Bernardi,Itiberê P.; Moro-Rios,Rodrigo F.; Passos,Fernando C.
This study was carried out in the Chácara Payquerê do Bugre, State of Paraná, Southern Brazil (25º29'52" S and 49º39'24" W) and reports on the demography of a group of Alouatta guariba clamitans Cabrera, 1940 followed monthly during three years (from February, 2002 to March, 2005). The growth and subsequent fission of the group are described and argued, as well as their possible underlying causes, focusing on the population ecology and social behavior of this taxa.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brown howlers; Dispersal; Group fission; Group growth; Population ecology.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752006000300013

Cryptic species in Pagamea coriacea sensu lato (Rubiaceae): evidence from morphology, ecology and reproductive behavior in a sympatric context
Provedor de dados: Acta Amazonica
Autores: Esteves,Samantha de Miranda; Vicentini,Alberto.
In this study we explore morphological and ecological variation in sympatric populations of Pagamea coriacea s.l. - a species complex from white-sand vegetation in the Amazon. A total of 147 trees were sampled and monitored at three nearby sites in Central Amazon, Brazil. Multivariate analyses of morphology indicated two distinct groups (A and B), which also differed in bark type, each containing subgroups associated with sexual dimorphism. However, a single hermaphroditic individual was observed within group B. As expected, all pistillate plants produced fruits, but 23% of the staminate plants of group B, and 5% of group A also produced fruits. This variation suggests that the sexual systems of both groups are between dioecy and gynodioecy. There was an...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Population ecology; Species delimitation; Reproductive system variation; White-sand forests; Amazonia.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672013000400003

Survival dynamics of Melocactus conoideus Buining &amp;amp; Brederoo (Cactaceae), a threatened species endemic to northeastern Brazil
Provedor de dados: Acta Botanica Brasilica
Autores: Luz-Freire,Hévila Prates; Trindade,Diego Pires Ferraz da; Sá-Neto,Raymundo José de; Corrêa,Michele Martins.
Studies on the survival of species are essential to understanding their biology and to developing effective conservation and management plans. This study aimed to determine the best model to explain the survival of the species Melocactus conoideus on the basis of time, density, age structure and habitat location, as well as to describe the interactions among those factors. The study was conducted in three M. conoideus habitat patches in the municipality of Vitória da Conquista, in the state of Bahia, Brazil, only one of which was within a "conservation unit" (protected area). In each patch, we selected 120 specimens of M. conoideus, which were marked with identification plates and classified by developmental stage and density. The survival of those...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cactus; Mortality; Population ecology; Spatial aggregation.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062014000200016

Population structure and fruit availability of the babassu palm ( Attalea speciosa Mart. ex Spreng) in human-dominated landscapes of the Northeast Region of Brazil
Provedor de dados: Acta Botanica Brasilica
Autores: Campos,Juliana Loureiro Almeida; Albuquerque,Ulysses Paulino; Peroni,Nivaldo; Araújo,Elcida de Lima.
ABSTRACT We studied the population structure and fruit availability of the babassu palm, Attalea speciosa, in three human-dominated landscapes located near a rural community in the region of Araripe, in the Northeast Region of Brazil, that were under intense fruit harvest. Fifty 10 x 10 m plots were randomly established in each of the three landscapes, and all individuals of A. speciosa within the plots were classified as seedlings, juveniles or adults, with the height of all adult individuals being measured. An additional 20 individuals were marked in each landscape, and the number of total bunches, fruits per bunch and bunches per palm tree were recorded. The populations of A. speciosa in the three landscapes exhibited an inverted J-shape plot, but...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Extractivism; Harvest; Landscape management; Non-timber forest products; Population ecology.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062017000200267

Ethnobotanical and ethnoecological study of Butia catarinensis Noblick &amp;amp; Lorenzi: contributions to the conservation of an endangered area in southern Brazil
Provedor de dados: Acta Botanica Brasilica
Autores: Kumagai,Leonardo; Hanazaki,Natalia.
Butia catarinensis Noblick &amp;amp; Lorenzi is a small palm (approximately 2 m high when full-grown) endemic to the southern coast of Brazil. Local farmers use the fruit and pulp for various purposes, and this extractive activity complements their income. The objective of this study was to understand the relationships between local people and B. catarinensis in its natural environment. Ethnobotanical and ethnoecological data were collected through participant observation, participatory research tools and semi-structured interviews. The density of B. catarinensis was measured in two areas, each containing twelve 10 m × 20 m plots. Interviewees recognized different varieties of the palm, its phenological stages, as well as potential pollinators and seed...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arecaceae; Atlantic Rainforest; Ethnobotany; Population ecology; Coastal sand dune vegetation.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062013000100002

Variação espaço-temporal na distribuição e abundância de Moenkhausia sanctaefilomenae (Characiformes: Characidae) em lagoas da planície de inundação do rio Cuiabá, Pantanal, Brasil - doi: 10.4025/actascibiolsci.v34i1.6809
Provedor de dados: Acta Scientiarum: Biological Sciences
Autores: Lourenço, Luzia da Silva; Universidade Estadual Paulista; Mateus, Lucia Aparecida de Fátima; Universidade Federal de Mato Grosso; Penha, Jerry Magno; Universidade Federal de Mato Grosso.
Identificar os fatores bióticos e abióticos que determinam a variação na distribuição e abundância das populações, tornou-se nos últimos anos um grande desafio para os ecologistas. Assim neste estudo foram avaliados o efeito das variáveis abióticas e a abundância de predadores sobre a abundância de Moenkhausia sanctaefilomenae, a variação no comprimento médio dos indivíduos entre lagoas e períodos e o efeito das variáveis abióticas e da abundância de predadores sobre a estrutura em comprimento. Foram amostradas 16 lagoas da planície de inundação do rio Cuiabá, no período de junho (vazante), setembro (seca) e dezembro (enchente) de 2005 e março (cheia) de 2006. Para M. sanctaefilomenae,a distribuição é mais ampla e a abundância é maior no final da vazante,...
Tipo: Abundância; Distribuição
Palavras-chave: 2.05.00.00-9 predação; Fatores abióticos; Estrutura populacional; Ecologia populacional Ecologia predation; Abiotic factors; Population structure; Population ecology.
Ano: 2011
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/6809