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Macrofaunal community abundance and diversity and talitrid orientation as potential indicators of ecological long-term effects of a sand-dune recovery intervention

Nourissona, Delphine Hélène; Bessa, Filipa; Scapini, Felicita; Marques, João Carlos
Fonte: Elsevier Ltd. Publicador: Elsevier Ltd.
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.25819%
In the last decades the increasing urban development on coastal areas have produced extensive modifications on shores all over the world, making critical the active management of pressures on sandy beaches. The use of engineering solutions to counteract beach erosion has been significantly increasing; the ecological indicators used to monitor these interventions generally focus on short- and medium-term effects, while little is known on their effectiveness on long-term temporal scales. The following ecological indicators have been tested in the present study: (a) macrofaunal community abundance and diversity and (b) orientation behaviour of Talitrus saltator, a talitrid amphipod widespread on Mediterranean and European Atlantic sandy beaches. Two sites were considered on a sandy beach of the Portuguese Atlantic coast, one located in front of a natural dune and the other at about 500 m of distance, where the dune had been rebuilt between 2000 and 2008 using geotextile tubes. In 2011 and 2012, macrofauna sampling and orientation experiments on T. saltator were performed at both sites in spring and autumn; contemporaneously the main environmental variables were registered. Macrofaunal data were analysed through multivariate statistical tests...

Fight versus flight: the interaction of temperature and body size determines antipredator behaviour in tegu lizards

BARROS, Fabio Cury de; CARVALHO, Jose Eduardo de; ABE, Augusto Shinya; KOHLSDOR, Tiana
Fonte: ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD Publicador: ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.071746%
Ectotherm antipredator behaviour might be strongly affected both by body temperature and size: when environmental temperatures do not favour maximal locomotor performance, large individuals may confront predators, whereas small animals may flee, simply because they have no other option. However, integration of body size and temperature effects is rarely approached in the study of antipredator behaviour in vertebrate ectotherms. In the present study we investigated whether temperature affects antipredator responses of tegu lizards, Tupinambis merianae, with distinct body sizes, testing the hypothesis that small tegus (juveniles) run away from predators regardless of the environmental temperature, because defensive aggression may not be an effective predator deterrent, whereas adults, which are larger, use aggressive defence at low temperatures, when running performance might be suboptimal. We recorded responses of juvenile (small) and adult (large) tegu lizards to a simulated predatory attack at five environmental temperatures in the laboratory. Most differences between the two size classes were observed at low temperatures: large tegus were more aggressive overall than were small tegus at all temperatures tested, but at lower temperatures...

Determinantes bionômicos e eco-químicos do cleptoparasitismo de Lestrimelitta limao Smith 1863 (Hymenoptera: Apidae, Meliponini); Bionomic and eco-chemical determinants of cleptoparasitic behaviour of Lestrimelitta limao (Hymenoptera: Apidae, Meliponini).

Zuben, Lucas Garcia Von
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 01/10/2012 Português
Relevância na Pesquisa
37.321216%
As relações entre flores e abelhas durante a evolução tiveram um importante papel na adaptação desses insetos, uma vez que eles se utilizam dos recursos florais (néctar e pólen) para sua alimentação. A adaptação a essa estratégia alimentar fica evidente pela presença de estruturas morfológicas nessas abelhas relacionadas à esse comportamento, como a corbícula. Apesar da utilização de recursos florais estar presente em praticamente todas as espécies de abelhas, algumas espécies de abelhas sem ferrão (Meliponini) apresentam um tipo de comportamento alimentar que difere bastante de todos os outros encontrados em abelhas sociais. No comportamento conhecido como cleptoparasita, as abelhas não visitam flores e conseguem seu alimento através do saque a outras colônias. Este comportamento está presente como estratégia exclusiva nos gêneros Lestrimelitta e Cleptotrigona. Durante o saque são levados da colônia pilhada, mel, pólen, cerúmen e, principalmente, alimento larval. Apesar de alguns estudos já terem sido realizados, muitas questões importantes relacionadas à ecologia química e comportamental do cleptoparasitismo ainda permaneciam sem respostas. Sendo assim, o presente estudo objetivou investigar esses dois aspectos do cleptoparasistismo em L. limao. Dentro do aspecto comportamental as análises se concentraram na investigação da escolha das colônias hospedeiras. As análises ecoquimícas...

Fight versus flight: the interaction of temperature and body size determines antipredator behaviour in tegu lizards

de Barros, Fabio Cury; de Carvalho, Jose Eduardo; Abe, Augusto Shinya; Kohlsdor, Tiana
Fonte: Academic Press Ltd Elsevier B.V. Ltd Publicador: Academic Press Ltd Elsevier B.V. Ltd
Tipo: Artigo de Revista Científica Formato: 83-88
Português
Relevância na Pesquisa
37.071746%
Ectotherm antipredator behaviour might be strongly affected both by body temperature and size: when environmental temperatures do not favour maximal locomotor performance, large individuals may confront predators, whereas small animals may flee, simply because they have no other option. However, integration of body size and temperature effects is rarely approached in the study of antipredator behaviour in vertebrate ectotherms. In the present study we investigated whether temperature affects antipredator responses of tegu lizards, Tupinambis merianae, with distinct body sizes, testing the hypothesis that small tegus (juveniles) run away from predators regardless of the environmental temperature, because defensive aggression may not be an effective predator deterrent, whereas adults, which are larger, use aggressive defence at low temperatures, when running performance might be suboptimal. We recorded responses of juvenile (small) and adult (large) tegu lizards to a simulated predatory attack at five environmental temperatures in the laboratory. Most differences between the two size classes were observed at low temperatures: large tegus were more aggressive overall than were small tegus at all temperatures tested, but at lower temperatures...

Cognitive and context “tuning”: tools to break anti-ecological habits

Gaspar, Rui; Palma-Oliveira, José Manuel; Wyer, Natalie; Corral-Verdugo, Victor
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
47.159634%
The fact that people do not behave in the way they are expected to, does not have to do only with a lack of motivation and intention but also with cognitive processes that might interfere with this. Even if the person has an intention to perform an ecological behavior, there can be barriers and constraints that prevent the pro-ecological goal of being attained. Accordingly, one of the techniques that can be used to increase the success in attaining pro-ecological behavioral goals is the development of implementation intentions. However, this technique is sometime ineffectively used due to a disregard of contextual characteristics. To overcome this, we propose the use of context “tuning” as a means to increase the effectiveness of habit change in a habitual context and thus, promote new behaviors in this same context. By conducting two studies, we promoted changes in the salience of the means to attain a behavioral goal, in order to facilitate the desired response elicited by implementation intentions. This was assessed in an online shopping simulation (study 1), with organic and non-organic products to choose from, in two variations of the same habitual context: equal salience (equally salient organic and non-organic goals) and lower salience context (organic goals less salient). Results showed that implementation intentions benefited from context “tuning”...

Why do people fail to act? Situational barriers and constraints on ecological behavior

Gaspar, Rui; Palma-Oliveira, José Manuel; Corral-Verdugo, Victor
Fonte: Nova Science Publishers Publicador: Nova Science Publishers
Tipo: Parte de Livro
Português
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47.27341%
The lack of success in dealing with the inconsistency between positive attitudes and ecological behaviors, and in explaining why people fail to act pro-environmentally is still widespread in practice and research. In our view, this has to do with three main reasons: 1) A positivity fallacy - the belief shared by many researchers and practitioners that as long as people have the right (or positive) attitudes, intentions, skills, information, etc., the right pro-ecological action should follow; thus, they disregard the importance of negative determinants in explaining the attitude-behavior inconsistency. 2) Lack of a psychological level of explanation; even when negative determinants are considered, the psychological explanation is often disregarded or incompletely identified, with most of the factors identified being socio-economical, or urban planning and architectural, etc. However, factors explaining why people fail to act can also be viewed within a psychological level of explanation, with behavior considered to be the result of an interaction between contextual variables and psychological processes. 3) Underestimation of the unconscious processes influence; contextual effects on behavior can be mediated not only by conscious perception but also by cognitive processes of which people are not aware of. Given these reasons...

Understanding the Reasons for Behavioral Failure: A Process View of Psychosocial Barriers and Constraints to Pro-Ecological Behavior

Gaspar, Rui
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
47.159634%
For many years now, behavior change projects and research on pro-ecological behavior seem to have encountered difficulties in answering the question: why do people fail to act? That is, what are the barriers and constraints that prevent people from acting in a pro-ecological way? In order to fill the gap, this paper aims to operationalize the concepts of barriers and constraints, based on an approach that considers the role of behavioral goals (“to achieve X”). In addition, it aims to present a preliminary approach focused on understanding the processes involved in the barriers and constraints emergence and their consequent effect on the implementation of behavioral goals into behaviors. This is done in order to allow for a better understanding of: (1) how the interaction between individual/dispositional characteristics and the characteristics of the situation in which individuals are in, may result in the inhibition/constraining of pro-ecological goals implementation into behaviors; and (2) the role of conscious and unconscious processes in this. Examples of barriers and constraints will be given, in order to make salient the need for future research to address these and for behavioral change projects to take them into consideration.

Performance of a stochastic-dynamic modelling methodology for running waters ecological assessment.

Cabecinha, Edna; Cortes, Rui; Cabral, João Alexandre
Fonte: Universidade de Trás-os-Montes e Alto Douro Publicador: Universidade de Trás-os-Montes e Alto Douro
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
37.472793%
An holistic stochastic-dynamic modelling methodology has been developed in order to predict the ecological status of lotic systems in Northeast Portugal. These procedures focus on the interactions between conceptually isolated key-components, such as some relevant benthic macroinvertebrate metrics and changes in local habitat conditions. The proposed model was preceded by a conventional multivariate statistical treatment performed to discriminate the significant relationships between prevailing biological and environmental variables. Since this statistical analysis is static, the dataset recorded from the field included true gradients of habitat changes. In this way, the factors time and space are implicit in the respective treatment. Such a procedure gives credibility to the parameters included in the dynamic model construction. In order to enhance the importance of monitoring in aquatic systems based on ecological integrity indicators, different biotic metrics were selected from the studied benthic macroinvertebrate communities. The samples of aquatic macroinvertebrate, environmental and physical-chemical data were collected from three watersheds of mountain rivers in Northeast Portugal, between 1983 and 1985. The model validation was based on independent data from another watershed not included in the model construction. Thereafter...

Impact of ecotourism on the fish fauna of Bonito region (Mato Grosso do Sul State, Brazil): ecological, behavioural and physiological measures

Lima,Ana Carolina; Assis,Jorge; Sayanda,Diogo; Sabino,José; Oliveira,Rui F.
Fonte: Sociedade Brasileira de Ictiologia Publicador: Sociedade Brasileira de Ictiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2014 Português
Relevância na Pesquisa
47.706113%
Bonito, in Mato Grosso do Sul State, is an important destination for ecotourism in Brazil and the main challenge of sustainable ecotourism here has been to accommodate and adjust the increase of tourism without compromising the ecological integrity of the local ecosystems. In this study we aimed to assess the environmental impact of ecotourism on the fish fauna of Sucuri River in Bonito by integrating ecological, behaviour and physiological criteria and using the fish species Crenicichla lepidota and Moenkhausia bonita as indicators. Two distinct sites were defined to collect data: (1) affected daily by ecotourism (Tourism) and (2) undisturbed (No Tourism). The "stationary point count" method was performed to assess variations in ecological parameters and "ad libitum" and focal animal methods were used to collect behaviour data. The cortisol response of M. bonita to a stress protocol was measured from holding-water. Results showed a significantly increase in species richness, density and diversity at the Tourism site. Nevertheless, behaviour patterns indicated a higher stress at the Tourism site for both species as well higher cortisol levels for M. bonita. In opposition to the ecological measures, the behaviour and physiological ones may be interpreted as an early sign of negative impact caused by ecotourism...

Values and antisocial behaviour during adolescence: The mediating and moderating roles of exposure to violence and moral cognitions

AQUILAR, SERENA
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
37.169756%
The present dissertation is composed by three independent studies. The first study aimed at testing the psychometric properties of the Portrait Values Questionnaire (PVQ; Schwartz et al., 2001) on a sample of Italian early adolescents, both to extend the validity of the Italian version of the PVQ and to examine the structure of values in early adolescence. 407 adolescents, aged fourteen years old, participated in the study. A first-order Confirmatory Factor Analysis to test the 10 factors model and a second-order Confirmatory Factor Analysis to test the model that includes the four higher order value dimensions were performed. The results supported the adequate psychometric properties of the instrument, in line with previous validation studies of the PVQ on adult samples, and revealed that in early adolescence the structure of values is well developed and very similar to that of adults; the only found difference was the impossibility to distinguish between the values of conformity and tradition. The second study aimed at investigating the impact of the selected values of universalism, conformity, power, and hedonism, and the impact of exposure to violence as a witness or a victim in different contexts (family, school, and neighborhood) on antisocial behaviour. In addition...

Ecology and behaviour of Pachycephala rufogularis and P. inornata (Aves: Pachycephalidae) in woodlands of South Australia.

Moise, Dragoş
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2009 Português
Relevância na Pesquisa
47.321216%
Since European settlement, the woodlands and associated habitats, especially in the temperate zones of Australia, have been extensively cleared and converted to arable land and pastures. Much of the remaining vegetation in the agricultural zone occurs as small isolated patches prone to disturbance and degradation. Apart from habitat loss and fragmentation, altered fire regimes, periods of intense drought, and the introduction of exotic plants and animals, have contributed to the deterioration of most of the natural habitats across Australia, with a negative impact on the native wildlife, including birds. Many woodland bird species have undergone widespread declines, culminating in some local or even regional extinctions. In the mallee woodlands of south-east Australia two closely related species of whistlers (fam. Pachycephalidae) — Red-lored Whistler Pachycephala rufogularis and Gilbert’s Whistler P. inornata — have overlapping ranges, and in some areas they co-exist. These two species are morphologically and ecologically similar. However, despite the similarities, P. rufogularis has undergone greater declines in distribution and abundance than P. inornata. The ecology of these two species is poorly known, which renders adequate management impracticable. The major objectives of this thesis were to determine the key habitat requirements for the two species...

Species interactions: estimating per-individual interaction strength and covariates before simplifying data into per-species ecological networks

Wells, K.; O'Hara, R.B.
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //2013 Português
Relevância na Pesquisa
37.092537%
1. Ecological network models based on aggregated data from species interactions are widely used to make inferences about species specialization, functionality and extinction risk. While increasing number of network data are available and are used in comparative studies, data quality and uncertainty have received little attention. Moreover, key individual-level information such as the proportion of individuals not involved in interactions and underlying processes driving interactions are ignored by aggregated data analysis. 2. We suggest an individual-level hierarchical interaction model as a more flexible approach to considering uncertainty, sampling effort and conditions under which interactions take place and from which network attributes can be derived. We performed a simulation exercise to compare inference under different sample sizes and from aggregated data matrices to those from our individual-level model. 3. Formalizing the process of network formation in an individual-level model made clear that per-species interaction frequencies are not independent of sample size and population pools and also ignore important information given by the proportion of non-interacting individuals. Hierarchical linear models are a possible solution to infer community-level attributes of network formation and allow various kinds of comprehensive model extensions to capture variation of per-individual interactions in space and time that shape upper level organization. 4. Individual-level hierarchical models provide the link between individual behaviour and interactions under variable environmental conditions and can be summarized into networks in a conceptually neat way. Such models may not only help to account for various sources of variation but also conceptualize aspects overlooked in aggregated data. In particular...

Effects of experience on the development of social behaviour of house-dwelling bats; Effetti dell'esperienza sullo sviluppo del comportamento sociale nei chirotteri antropofili

ANCILLOTTO, LEONARDO
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
37.169756%
This study aims at clarifying the mechanisms underlying the formation and maintenance of stable social units in bats (Chiroptera), a characteristic shared by most species of this group of mammals, by investigating the effects of the early social environment, i.e. pursuing the hypothesis that imprinting-like influences on the development of social behaviour exist and may have a profound impact on the social lives of bats. First I present an overview on bats' social behaviour and systems: these mammals comprise a high number of species and thus constitute an excellent group for testing general hypotheses about evolution and development of social behaviour. Bat social systems in fact range from solitary species to others aggregating in conspicuous groups of up to millions individuals. Such complexity leads to a variety of social behaviours rarely found in other taxonomic groups: there is increasing evidence that bats are able of cooperative social behaviours such as allogrooming, communal nursing, group hunting and social learning, all interactions that require high-level cognitive skills. Investigating such a complex system needs a multi-disciplinary approach, fundamental for disentangling the mechanisms through which bat sociality develops. I performed a series of experiments and used classical ethological and statistical methods (ethogram composition...

Impact of ecotourism on the fish fauna of Bonito region (Mato Grosso do Sul State, Brazil): ecological, behavioural and physiological measures

Lima, Ana Carolina; Assis, Jorge; Sayanda, Diogo; Sabino, José; Oliveira, Rui F.
Fonte: Scielo Publicador: Scielo
Tipo: Artigo de Revista Científica
Publicado em /03/2014 Português
Relevância na Pesquisa
47.706113%
Bonito, in Mato Grosso do Sul State, is an important destination for ecotourism in Brazil and the main challenge of sustainable ecotourism here has been to accommodate and adjust the increase of tourism without compromising the ecological integrity of the local ecosystems. In this study we aimed to assess the environmental impact of ecotourism on the fish fauna of Sucuri River in Bonito by integrating ecological, behaviour and physiological criteria and using the fish species Crenicichla lepidota and Moenkhausia bonita as indicators. Two distinct sites were defined to collect data: (1) affected daily by ecotourism (Tourism) and (2) undisturbed (No Tourism). The "stationary point count" method was performed to assess variations in ecological parameters and "ad libitum" and focal animal methods were used to collect behaviour data. The cortisol response of M. bonita to a stress protocol was measured from holding-water. Results showed a significantly increase in species richness, density and diversity at the Tourism site. Nevertheless, behaviour patterns indicated a higher stress at the Tourism site for both species as well higher cortisol levels for M. bonita. In opposition to the ecological measures, the behaviour and physiological ones may be interpreted as an early sign of negative impact caused by ecotourism...

The integration of GPS, vegetation mapping and GIS in ecological and behavioural studies

Rutter,Steven Mark
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2007 Português
Relevância na Pesquisa
37.639019%
Global Positioning System (GPS) satellite navigation receivers are increasingly being used in ecological and behavioural studies to track the movements of animals in relation to the environments in which they live and forage. Concurrent recording of the animal's foraging behaviour (e.g. from jaw movement recording) allows foraging locations to be determined. By combining the animal GPS movement and foraging data with habitat and vegetation maps using a Geographical Information System (GIS) it is possible to relate animal movement and foraging location to landscape and habitat features and vegetation types. This powerful approach is opening up new opportunities to study the spatial aspects of animal behaviour, especially foraging behaviour, with far greater precision and objectivity than before. Advances in GPS technology now mean that sub-metre precision systems can be used to track animals, extending the range of application of this technology from landscape and habitat scale to paddock and patch scale studies. As well as allowing ecological hypotheses to be empirically tested at the patch scale, the improvements in precision are also leading to the approach being increasing extended from large scale ecological studies to smaller (paddock) scale agricultural studies. The use of sub-metre systems brings both new scientific opportunities and new technological challenges. For example...

Ecological plasticity by morphological design reduces costs of subordination: influence on species distribution

Moreno, Eulalia; Barluenga, Marta; Barbosa, Andrés
Fonte: Springer Publicador: Springer
Tipo: Artículo Formato: 25088 bytes; application/msword
Português
Relevância na Pesquisa
37.562988%
We studied the feeding behaviour of two subordinate tit species (Parus spp.) in two competitive contexts: feeding solitarily versus feeding in the presence of the dominant great tit. Considering ecological plasticity as the within-species component of mean behavioural performance associated with different morphologies in different species, we test the hypothesis that subordinate species with morphological designs allowing a greater ecological plasticity (e.g. blue tit whose hindlimb morphology is modified for greater leg flexion) may gain an advantage against subordinate species with a less plastic design (e.g. crested tit whose hindlimb morphology is modified for aid in leg extension) in a competitive context. Our results demonstrate that the blue tit has greater foraging abilities than the crested tit, as the former is able to modify its feeding behaviour in the presence of the dominant great tit significantly more than the crested tit. In light of these results we propose that some subordinate species can take advantage of their greater ecological plasticity against another less plastic, subordinate species, suggesting that ecological plasticity due to morphological design is a way of reducing costs of subordination as well as a novel...

Species richness, interaction networks, and diversification in bird communities a synthetic ecological and evolutionary perspective/

Carnicer i Cols, Jofre
Fonte: Bellaterra: Universitat Autònoma de Barcelona, Publicador: Bellaterra: Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf
Publicado em //2008 Português
Relevância na Pesquisa
37.4065%
Consultable des del TDX; Títol obtingut de la portada digitalitzada; Aquesta tesi examina els mecanismes ecològics i evolutius que mantenen els gradients de riquesa específica en ocells. S'examinen en primer lloc el patrons de diversitat de l'avifauna de Nord Amèrica. (capitol 1). Tot seguit es testen mecanismes a escala regional, tot estudiant el cas de l'avifauna de Catalunya (capitols 2 i 3). Finalment, es testen diferents mecanismes que regulen la diversitat a escala local en una comunitat d'ocells frugívors al Parc nacional de Doñana. El capitol 6 integra tots els anteriors i els relaciona tot fent una revisió bibliogràfica en profunditat.; Species richness gradients have been analyzed during many decades and they have progressively emerged as a central topic in community ecology (Darwin 1859, Wallace 1878, Willis 1922, Dobzhansky 1950, Fisher 1960, Hillebrand 2004, Riclkefs 2004, Mittelbach et al. 2007, among others). Historically, species richness gradients have been analyzed from two main points of view: the ecological and the evolutionary perspective (Ricklefs 2004, 2006b). The ecological perspective assumes that populations are evolutionarily fixed and studies species richness gradients as the result of regional colonization and extinction processes...

Motivations and incentives for pro-environmental behaviour: the case of silvopasture adoption in the tropical forest frontier

Zabala, Aiora
Fonte: University of Cambridge; Department of Land Economy Publicador: University of Cambridge; Department of Land Economy
Tipo: Thesis; doctoral; PhD
Português
Relevância na Pesquisa
37.097239%
On the frontier of biodiversity-rich tropical forests, how land is used has an important role in buffering the primary ecosystem. Unsustainable small-scale cattle farming endangers soil quality and degrades the landscape. Silvopasture is a type of agroforestry that provides both ecological and livelihood benefits. A number of projects have been implemented across the tropics to encourage silvopasture adoption, with varying success. This dissertation questions the reasons for variable outcomes among participants within these projects: what motivates smallholders to adopt innovative land-use practices, and what form of incentives may help to overcome obstacles and catalyse adoption. This dissertation contributes to the ongoing debate on payments for ecosystem services, specifically about their suitability and effectiveness. To understand what influences decisions to adopt sustainable land-use practices, I review systematically and quantitatively the literature on adoption predictors, and I empirically analyse participation and short-term adoption in a pilot project for planting fodder trees in the border of a protected forest in Chiapas, Mexico, using primary and secondary data. I focus on subjective perspectives and livelihood strategies of actual and potential participants as explanatory variables...

Amazônia socioambiental: sustentabilidade ecológica e diversidade social

Lima, Deborah; Pozzobon, Jorge
Fonte: Universidade de São Paulo. Instituto de Estudos Avançados Publicador: Universidade de São Paulo. Instituto de Estudos Avançados
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/08/2005 Português
Relevância na Pesquisa
47.424336%
ESTE ARTIGO baseia-se no emprego de um conceito central do discurso ambientalista - o de sustentabilidade ecológica - para construir um quadro analítico da diversidade socioambiental da Amazônia contemporânea. O exercício consiste em um ordenamento geral de categorias sociais segundo seu comportamento ambiental. Este é o ponto de partida para uma análise dos fundamentos históricos, econômicos e culturais da sustentabilidade ecológica atribuída a cada segmento social. A análise mostra a complexidade da interação entre múltiplos fatores que explicam o comportamento ecológico particular de cada um dos seguintes segmentos sociais considerados: a) povos indígenas de comércio esporádico, b) povos indígenas de comércio recorrente, c) povos indígenas dependentes da produção mercantil, d) pequenos produtores "tradicionais", e) latifúndios "tradicionais", f) latifúndios recentes, g) migrantes/ fronteira, h) grandes projetos e i) exploradores itinerantes. Com este exercício, alguns estereótipos consagrados são contrariados, como aqueles que relacionam baixa sustentabilidade ecológica com pobreza, ou alta sustentabilidade ecológica com identidade indígena. Concluímos mostrando a importância de prosseguir com análises de amplo espectro para entender a diversidade socioambiental da Amazônia.; WITH ONE of the central concepts of environmental discourse - that of ecological sustainability - we analyse the social diversity of contemporary Amazonia...

Metabolic correlates of the foraging and social behaviour of dart-poison frogs

Pough, F. Harvey; Taigen, Theodore
Fonte: Elsevier: Animal Behaviour Publicador: Elsevier: Animal Behaviour
Tipo: Artigo de Revista Científica Formato: 37365 bytes; application/pdf
Português
Relevância na Pesquisa
37.379019%
The foraging and social behaviour of four species of Panamanian dart-poison frogs, Dendrobatidae, were recorded and that information was combined with an analysis of aerobic and anaerobic metabolism and with published information about food habits to test predictions about associations among behavioural, ecological and physiological characteristics of anurans. Several generalizations were supported by the data. The widely foraging species of frogs made more prey capture attempts in total and took more prey at each feeding station than did the sedentary species. The widely foraging species had higher capacities for aerobic metabolism and lower anaerobic capacities than did the sedentary species. Other generalizations were not supported. Dietary habits were only loosely related to foraging mode and neither aerobic capacity nor foraging mode was a good predictor of the frequency of vocalization or of agonistic behaviour. High aerobic capacity and widely foraging behaviour may be derived characters in the family Dendrobatidae, but the metabolic and behavioural requirements of territorial defence provide an alternate hypothesis for the association of some ecological and physiological characteristics of frogs.