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Food acquisition is a fundamental process that drives animal distribution and abundance, influencing how species respond to changing environments. Disturbances such as fire create significant shifts in available dietary resources, yet, for many species, we lack basic information about what they eat, let alone how they respond to a changing resource base. In order to create effective management strategies, faunal conservation in flammable landscapes requires a greater understanding of what animals eat and how this change following a fire. What animals eat in postfire environments has received little attention due to the time-consuming methodologies and low-resolution identification of food taxa. Recently, molecular techniques have been developed to identify food DNA in scats, making it possible to identify animal diets with enhanced resolution. The primary aim of this study was to utilize eDNA metabarcoding to obtain an improved understanding of the diet of three native Australian small mammal species: yellow-footed antechinus (Antechinus flavipes), heath mouse (Pseudomys shortridgei), and bush rat (Rattus fuscipes). Specifically, we sought to understand the difference in the overall diet of the three species and how diet changed over time after fire. Yellow-footed antechinus diets mostly consisted of moths, and plants belonging to myrtles and legume families while bush rats consumed legumes, myrtles, rushes, and beetles. Heath mouse diet was dominated by rushes. All three species shifted their diets over time after fire, with most pronounced shifts in the bush rats and least for heath mice. Identifying critical food resources for native animals will allow conservation managers to consider the effect of fire management actions on these resources and help conserve the species that use them.
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Edges are ecologically important environmental features and have been well researched in agricultural and urban landscapes. However, little work has been conducted in flammable ecosystems where spatially and temporally dynamic fire edges are expected to influence important processes such as recolonization of burnt areas and landscape connectivity. We review the literature on fire, fauna, and edge effects to summarize current knowledge of faunal responses to fire edges and identify knowledge gaps. We then develop a conceptual model to predict faunal responses to fire edges and present an agenda for future research. Faunal abundance at fire edges changes over time, but patterns depend on species traits and resource availability. Responses are also influenced by edge architecture (e.g., size and shape), site and landscape context, and spatial scale. However, data are limited and the influence of fire edges on both local abundance and regional distributions of fauna is largely unknown. In our conceptual model, biophysical properties interact with the fire regime (e.g., patchiness, frequency) to influence edge architecture. Edge architecture and species traits influence edge permeability, which is linked to important processes such as movement, resource selection, and species interactions. Predicting the effect of fire edges on fauna is challenging, but important for biodiversity conservation in flammable landscapes. Our conceptual model combines several drivers of faunal fire responses (biophysical properties, regime attributes, species traits) and will therefore lead to improved predictions. Future research is needed to understand fire as an agent of edge creation; the spatio-temporal flux of fire edges across landscapes; and the effect of fire edges on faunal movement, resource selection, and biotic interactions. To aid the incorporation of new data into our predictive framework, our model has been designed as a Bayesian Network, a statistical tool capable of analyzing complex environmental relationships, dealing with data gaps, and generating testable hypotheses.
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Common goals of ecological fire management are to sustain biodiversity and minimize extinction risk. A novel approach to achieving these goals determines the relative proportions of vegetation growth stages (equivalent to successional stages, which are categorical representations of time since fire) that maximize a biodiversity index. The method combines data describing species abundances in each growth stage with numerical optimization to define an optimal growth-stage structure that provides a conservation-based operational target for managers. However, conservation targets derived from growth-stage optimization are likely to depend critically on choices regarding input data. There is growing interest in the use of growth-stage optimization as a basis for fire management, thus understanding of how input data influence the outputs is crucial. Simulated data sets provide a flexible platform for systematically varying aspects of survey design and species inclusions. We used artificial data with known properties, and a case-study data set from southeastern Australia, to examine the influence of (1) survey design (total number of sites and their distribution among growth stages) and (2) species inclusions (total number of species and their level of specialization) on the precision of conservation targets. Based on our findings, we recommend that survey designs for precise estimates would ideally involve at least 80 sites, and include at least 80 species. Greater numbers of sites and species will yield increasingly reliable results, but fewer might be sufficient in some circumstances. An even distribution of sites among growth stages was less important than the total number of sites, and omission of species is unlikely to have a major influence on results as long as several species specialize on each growth stage. We highlight the importance of examining the responses of individual species to growth stage before feeding survey data into the growth-stage optimization black box, and advocate use of a resampling procedure to determine the precision of results. Collectively, our findings form a reproducible guide to designing ecological surveys that yield precise conservation targets through growth-stage optimization, and ultimately help sustain biodiversity in fire-prone systems.
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Biodiversidade , Conservação dos Recursos Naturais , Ecologia/métodos , Incêndios , Animais , Modelos Estatísticos , VitóriaRESUMO
Invasive and over-abundant predators pose a major threat to biodiversity and often benefit from human activities. Effective management requires understanding predator use of human-modified habitats (including resource subsidies and disturbed environments), and individual variation within populations. We investigated selection for human-modified habitats by invasive red foxes, Vulpes vulpes, within two predominantly forested Australian landscapes. We predicted that foxes would select for human-modified habitats in their range locations and fine-scale movements, but that selection would vary between individuals. We GPS-tracked 19 foxes for 17-166 days; ranges covered 33 to >2500 ha. Approximately half the foxes selected for human-modified habitats at the range scale, with some 'commuting' more than five kilometres to farmland or townships at night. Two foxes used burnt forest intensively after a prescribed fire. In their fine-scale nocturnal movements, most foxes selected for human-modified habitats such as reservoirs, forest edges and roads, but there was considerable individual variation. Native fauna in fragmented and disturbed habitats are likely to be exposed to high rates of fox predation, and anthropogenic food resources may subsidise fox populations within the forest interior. Coordinating fox control across land-tenures, targeting specific landscape features, and limiting fox access to anthropogenic resources will be important for biodiversity conservation.
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Conservação dos Recursos Naturais , Florestas , Espécies Introduzidas/tendências , Comportamento Predatório , Animais , Austrália , Feminino , Raposas , Sistemas de Informação Geográfica , Espécies Introduzidas/estatística & dados numéricos , Masculino , Dinâmica Populacional/estatística & dados numéricos , Dinâmica Populacional/tendências , Tecnologia de Sensoriamento Remoto , Análise Espaço-TemporalRESUMO
Fire plays an important role in structuring vegetation in fire-prone regions worldwide. Progress has been made towards documenting the effects of individual fire events and fire regimes on vegetation structure; less is known of how different fire history attributes (e.g., time since fire, fire frequency) interact to affect vegetation. Using the temperate eucalypt foothill forests of southeastern Australia as a case study system, we examine two hypotheses about such interactions: (1) post-fire vegetation succession (e.g., time-since-fire effects) is influenced by other fire regime attributes and (2) the severity of the most recent fire overrides the effect of preceding fires on vegetation structure. Empirical data on vegetation structure were collected from 540 sites distributed across central and eastern Victoria, Australia. Linear mixed models were used to examine these hypotheses and determine the relative influence of fire and environmental attributes on vegetation structure. Fire history measures, particularly time since fire, affected several vegetation attributes including ground and canopy strata; others such as low and sub-canopy vegetation were more strongly influenced by environmental characteristics like rainfall. There was little support for the hypothesis that post-fire succession is influenced by fire history attributes other than time since fire; only canopy regeneration was influenced by another variable (fire type, representing severity). Our capacity to detect an overriding effect of the severity of the most recent fire was limited by a consistently weak effect of preceding fires on vegetation structure. Overall, results suggest the primary way that fire affects vegetation structure in foothill forests is via attributes of the most recent fire, both its severity and time since its occurrence; other attributes of fire regimes (e.g., fire interval, frequency) have less influence. The strong effect of environmental drivers, such as rainfall and topography, on many structural features show that foothill forest vegetation is also influenced by factors outside human control. While fire is amenable to human management, results suggest that at broad scales, structural attributes of these forests are relatively resilient to the effects of current fire regimes. Nonetheless, the potential for more frequent severe fires at short intervals, associated with a changing climate and/or fire management, warrant further consideration.
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Incêndios , Florestas , Austrália , Clima , EcossistemaRESUMO
Disturbance regimes are changing worldwide, and the consequences for ecosystem function and resilience are largely unknown. Functional diversity (FD) provides a surrogate measure of ecosystem function by capturing the range, abundance and distribution of trait values in a community. Enhanced understanding of the responses of FD to measures of vegetation structure at landscape scales is needed to guide conservation management. To address this knowledge gap, we used a whole-of-landscape sampling approach to examine relationships between bird FD, vegetation diversity and time since fire. We surveyed birds and measured vegetation at 36 landscape sampling units in dry and wet forest in southeast Australia during 2010 and 2011. Four uncorrelated indices of bird FD (richness, evenness, divergence and dispersion) were derived from six bird traits, and we investigated responses of these indices and species richness to both vertical and horizontal vegetation diversity using linear mixed models. We also considered the extent to which the mean and diversity of time since fire were related to vegetation diversity. Results showed opposing responses of FD to vegetation diversity in dry and wet forest. In dry forest, where fire is frequent, species richness and two FD indices (richness and dispersion) were positively related to vertical vegetation diversity, consistent with theory relating to environmental variation and coexistence. However, in wet forest subject to infrequent fire, the same three response variables were negatively associated with vertical diversity. We suggest that competitive dominance by species results in lower FD as vegetation diversity increases in wet forest. The responses of functional evenness were opposite to those of species richness, functional richness and dispersion in both forest types, highlighting the value of examining multiple FD metrics at management-relevant scales. The mean and diversity of time since fire were uncorrelated with vegetation diversity in wet forest, but positively correlated with vegetation diversity in dry forest. We therefore suggest that protection of older vegetation is important, but controlled application of low-severity fire in dry forest may sustain ecosystem function by enhancing different elements of FD.
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Aves/fisiologia , Florestas , Animais , Austrália , Biodiversidade , Ecossistema , Modelos Lineares , Dinâmica PopulacionalRESUMO
Animal species diversity is often associated with time since disturbance, but the effects of disturbances such as fire on functional diversity are unknown. Functional diversity measures the range, abundance, and distribution of trait values in a community, and links changes in species composition with the consequences for ecosystem function. Improved understanding of the relationship between time since fire (TSF) and functional diversity is critical given that the frequency of both prescribed fire and wildfire is expected to increase. To address this knowledge gap, we examined responses of avian functional diversity to TSF and two direct measures of environmental heterogeneity, plant diversity, and structural heterogeneity. We surveyed birds across a 70-year chronosequence spanning four vegetation types in southeast Australia. Six bird functional traits were used to derive four functional diversity indices (richness, evenness, divergence, and dispersion) and the effects of TSF, plant diversity and structural heterogeneity on species richness and the functional diversity indices were examined using mixed models. We used a regression tree method to identify traits associated with species more common in young vegetation. Functional richness and dispersion were negatively associated with TSF in all vegetation types, suggesting that recent prescribed fire generates heterogeneous vegetation and provides greater opportunities for resource partitioning. Species richness was not significantly associated with TSF, and is probably an unreliable surrogate for functional diversity in fire-prone systems. A positive, relationship between functional evenness and structural heterogeneity was comnon to all vegetation types, suggesting that fine-scale (tens of meters) structural variation can enhance ecosystem function. Species more common in young vegetation were primarily linked by their specialist diets, indicating that ecosystem services such as seed dispersal and insect control are enhanced in more recently burnt vegetation. We suggest that patchy prescribed fire sustains functional diversity, and that controlled use of patchy fire to break up large expanses of mature vegetation will enhance ecosystem function.
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Aves/classificação , Aves/fisiologia , Ecossistema , Incêndios , Animais , Austrália , Comportamento Alimentar , Modelos Biológicos , Dinâmica Populacional , Fatores de TempoRESUMO
Predicting the effects of fire on biota is important for biodiversity conservation in fire-prone landscapes. Time since fire is often used to predict the occurrence of fauna, yet for many species, it is a surrogate variable and it is temporal change in resource availability to which animals actually respond. Therefore prediction of fire-fauna relationships will be uncertain if time since fire is not strongly related to resources. In this study, we used a space-for-time substitution across a large diverse landscape to investigate interrelationships between the occurrence of ground-dwelling mammals, time since fire, and structural resources. We predicted that much variation in habitat structure would remain unexplained by time since fire and that habitat structure would predict species' occurrence better than time since fire. In line with predictions, we found that time since fire was moderately correlated with habitat structure yet was a poor surrogate for mammal occurrence. Variables representing habitat structure were better predictors of occurrence than time since fire for all species considered. Our results suggest that time since fire is unlikely to be a useful surrogate for ground-dwelling mammals in heterogeneous landscapes. Faunal conservation in fire-prone landscapes will benefit from a combined understanding of fauna-resource relationships and the ways in which fire (including planned fires and wildfires) alters the spatial and temporal distribution of faunal resources.
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Ecossistema , Monitoramento Ambiental , Incêndios , Animais , Austrália , Conservação dos Recursos Naturais , Mamíferos/fisiologia , Modelos Biológicos , Plantas , Dinâmica PopulacionalRESUMO
Society has a negative attitude toward people with intellectual disabilities or psychiatric disabilities. It is well documented that they are subjected to prejudice, stigma, and negative attitudes (Di Giulio, 2003; Finger, 1994). Professional literature indicates that information about disabilities and encounters with persons with disabilities can change negative attitudes (Carter, Hughes, Copeland, & Breen, 2001; Krajewski & Flaherty, 2000). This study accompanied 164 9th-grade students from various junior high schools throughout Israel. Half of the students participated in an integration program for changing attitudes toward persons with disabilities, and the other half served as the control group. The research examined the existence and the degree of relationship between participation in the program, changes in attitudes toward people with disabilities, and self-image. The research findings pointed to a positive change in attitudes of the participants of the program in comparison with the control group, resulting mainly from personal contact with people with disabilities. No relationship was found between levels of self-image of the research group and attitudes toward people with disabilities.
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Comportamento do Adolescente , Pessoas com Deficiência/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Liderança , Autoimagem , Percepção Social , Adaptação Psicológica , Adolescente , Distribuição de Qui-Quadrado , Educação , Feminino , Humanos , Relações Interpessoais , Masculino , Psicometria , Estresse Psicológico , Inquéritos e Questionários , VoluntáriosRESUMO
Biodynamic (BD) agriculture, a form of organic agriculture, includes the use of specially fermented preparations, but peer-reviewed studies on their efficacy are rare. Composting of a grape pomace and manure mixture was studied in two years (2002 and 2005) with and without the BD compost preparations. Water extracts of finished composts were then used to fertigate wheat seedlings, with and without added inorganic fertilizer. BD-treated mixtures had significantly greater dehydrogenase activity than did untreated (control) mixtures during composting, suggesting greater microbial activity in BD-treated compost. In both years there was a distinct compost effect on wheat shoot and root biomass irrespective of supplemental fertilizer. Shoot biomass was highest in all treatments receiving 1% compost extract. Wheat seedlings that received 1% compost extract in 2005 grew similar root and shoot biomass as fertilized seedlings, despite only containing 30% as much nitrogen as the fertilizer treatment. In both years seedlings that received fertilizer plus 1% compost extract produced 22-61% more shoot biomass and 40-66% more root biomass than seedlings that received fertilizer alone, even at higher rates. In 2002 a 1% extract of BD compost grew 7% taller wheat seedlings than did 1% extract of untreated compost. At 0.1% only BD extract grew taller plants than water, but in 2002 only. No effect on shoot or root biomass was seen at 0.1%. Our results support the use of compost extracts as fertilizer substitutes or supplements, testimonial reports on the growth promoting effects of compost extracts, and the occasional superiority of BD compost to untreated compost.
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Plântula/crescimento & desenvolvimento , Solo , Triticum/genética , Bioensaio , Biomassa , Biotecnologia/métodos , Fertilização , Fertilizantes , Esterco , Nitrogênio/química , Oxigênio/química , Raízes de Plantas/metabolismo , Compostos de Amônio Quaternário/química , Fatores de Tempo , VitisRESUMO
Perceived altruism, an attitude that clients may attribute to those who work with them, was examined in a qualitative and quantitative study about the impact of volunteers in drop-in centers for youth at risk in Israel. Data were collected by interviews, observations, case studies, and questionnaires. The results show that the volunteers' unique contribution affected the service as a whole. The beneficiaries knew that volunteers were servicing them, perceived volunteers as true altruists, were satisfied to the degree of preferring their services over that of paid workers, and were positively affected by the encounter with volunteering. A significant impact was that volunteers set a living example of the possibility of human goodness via personal encounters and demonstrated the existence of a responsive society with mutual, unconditional caring. These results exhibit practical implications for innovative interventions with youth at risk and illustrate the significance of the psychology of goodness.
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Altruísmo , Redes Comunitárias , Voluntários , Adolescente , Adulto , Comportamento do Consumidor , Feminino , Humanos , Israel , Masculino , Adulto JovemRESUMO
Terrorism and its aftermath have become part of the Western way of life, and social workers have a central role to play in helping affected families and their communities. Drawing on community-based experience in Israeli communities, the authors examine the planning of multidisciplinary teams and how their planning was put into effect in their communities in several terrorist attacks. The authors use reports of social workers, community volunteers, and clients to map the phases of the activity, the roles and goals of the social workers with different focal systems during the phase stages, and the tasks that the social workers carried out.
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Planejamento em Saúde Comunitária/organização & administração , Planejamento em Desastres/organização & administração , Papel Profissional , Serviço Social/organização & administração , Terrorismo , Participação da Comunidade/métodos , Implementação de Plano de Saúde , Humanos , Entrevistas como Assunto , Israel , Serviço Social/métodos , Voluntários/organização & administraçãoRESUMO
This study examined the association of key variables with the intention to disclose and actual disclosure to an additional significant other of being HIV-infected. Sixty-five participants were recruited from five AIDS/HIV centers in Israeli hospitals. Participants completed questionnaires at entry to the study. They were asked about the extent to which they had already disclosed being HIV-infected, their intentions regarding future disclosure, and their emotional state; six months later their disclosure was examined. Depression and shame affected the intention to disclose the secret. Disclosure was associated with being male, having a high level of depression and shame, and having a low level of education. Participants with high levels of guilt who stated that they intended to disclose the secret were most likely to have done so. Implications for practice are discussed.
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Confidencialidade/psicologia , Infecções por HIV/psicologia , Relações Interpessoais , Autorrevelação , Revelação da Verdade , Adulto , Análise de Variância , Busca de Comunicante , Depressão/complicações , Depressão/psicologia , Feminino , Seguimentos , Infecções por HIV/complicações , Infecções por HIV/etnologia , Humanos , Israel , Masculino , Pessoa de Meia-Idade , Autoavaliação (Psicologia) , Fatores Sexuais , Vergonha , Fatores SocioeconômicosRESUMO
This article describes a community organization program and its tangible results in a stigmatized neighborhood in the center of Israel. The program lasted six years; its central goal was the autonomy of the community, the empowerment of its residents, and collaboration among the human services workers and between them and the resident leaders. The results, measured objectively and quantitatively, included a large increase in the number of community activists; strong and statistically significant increases of self-esteem and mastery of surroundings; increase in family, service delivery, and community empowerment among the activists, and the participation of residents and outsiders in a project to build their own homes in the neighborhood.