141 resultados para Weed communities
Resumo:
Purpose – This paper seeks to present findings from the first all-Ireland study that consulted older people on their perceptions of interventions and services to support people experiencing abuse.
Design/methodology/approach – Utilising a grounded theory approach, 58 people aged 65 years and over took part in focus groups across Ireland. Four peer-researchers were also trained to assist in recruitment, data collection, analysis, and dissemination.
Findings – Participants identified preventative community-based approaches and peer supports as important mechanisms to support people experiencing, and being at risk of, elder abuse. Choices regarding care provision and housing, as well as opportunities for engagement in community activities where they can discuss issues with others, were identified as ways to prevent abuse.
Originality/value – The development of elder abuse services has traditionally been defined from the perspective of policy makers and professionals. This study looked at the perspective of the end-users of such services for the first time. The research also gave an active role to older people in the research process. The policy implication of the findings from this research is that enhanced attention and resources should be directed to community activities that enable older people to share their concerns informally thereby gaining confidence to seek more formal interventions when necessary.
Resumo:
Mycorrhizal fungi form complex communities in the root systems of most plant species and are thought to be important in terrestrial ecosystem sustainability. We have reviewed the literature relating to the influence of the major forms of anthropogenic pollution on the structure and dynamics of mycorrhizal fungal communities. All forms of pollution have been reported to alter the structure of below-ground communities of mycorrhizal fungi to some degree, although the extent to which such changes will be sustained in the longer term is at present not clear. The major limitation to predicting the consequences of pollution-mediated changes in mycorrhizal fungal communities to terrestrial habitats is our limited understanding of the functional significance of mycorrhizal fungal diversity. While this is identified as a priority area for future research, it is suggested that, in the absence of such data, an understanding of pollution-mediated changes in mycorrhizal mycelial systems in soil may provide useful indicators for sustainability of mycorrhizal systems.
Resumo:
The prediction and management of ecosystem responses to global environmental change would profit from a clearer understanding of the mechanisms determining the structure and dynamics of ecological communities. The analytic theory presented here develops a causally closed picture for the mechanisms controlling community and population size structure, in particular community size spectra, and their dynamic responses to perturbations, with emphasis on marine ecosystems. Important implications are summarised in non-technical form. These include the identification of three different responses of community size spectra to size-specific pressures (of which one is the classical trophic cascade), an explanation for the observed slow recovery of fish communities from exploitation, and clarification of the mechanism controlling predation mortality rates. The theory builds on a community model that describes trophic interactions among size-structured populations and explicitly represents the full life cycles of species. An approximate time-dependent analytic solution of the model is obtained by coarse graining over maturation body sizes to obtain a simple description of the model steady state, linearising near the steady state, and then eliminating intraspecific size structure by means of the quasi-neutral approximation. The result is a convolution equation for trophic interactions among species of different maturation body sizes, which is solved analytically using a novel technique based on a multiscale expansion.
Resumo:
The research on Estonia, Latvia and Lithuania has pointed out some controversial social and political developments since the collapse of the Soviet Union. Crucially, there is a discrepancy between the governments' commitment to creating democratic political regimes, to ensuring harmonious social relations and to accommodating the ethno-cultural diversity of the resident communities. In reflecting on the legacies of the Soviet past, the book addresses the role non-titular populations have played in the process of democratisation and the relation between the states, societies and minorities in the post-Soviet Baltic states. The argument proceeds along three lines. Firstly, the book examines the institutional dimension of democratisation in the region, thereby addressing the processes of state- and nation-building as reflected in various policy-developments. Secondly, it compares the impact of ethno-cultural diversity on the development of the respective Baltic nation-states. The discussion makes clear that the framework of Baltic political communities was designed to suit the interests of the titular groups and thus resulted in the marginalisation of the minority communities. Thirdly, the book assesses the participation of minority communities in the development, criticism and improvement of state institutions and policies since independence. The analysis points out that, two decades after independence, the post-Soviet Baltic states and societies are seen by many members of the majority groups as primarily serving the interests of their ethnic community. In this situation, the members of the non-titular communities need to adapt to the majorities' perceptions in order to benefit from the achievements of democratisation.
Resumo:
Research and processes of knowledge production are often based on racialised and imperialistic frameworks that have either led to the exclusion or pathologisation of minority groups. Researchers address issues of exclusion by adopting recruitment strategies that involve negotiating with gatekeepers to ensure the inclusion of minority or marginalised groups. This often involves in-depth scrutiny of gatekeepers and requires the researchers to negotiate deals and to make personal disclosures. However, there remains relatively little discussion on the pragmatic ethical issues facing researchers in the field as a result of these interactions.
This paper suggests that interactions with gatekeepers present ethical issues that can be effectively addressed and managed by researchers through the exercise of phronesis. This allows researchers to make critical ethical decisions based on the specific characteristics of the research sites and subjects, not least of which are those issues that emerge as a consequence of researcher positionality. Such decisions are not necessarily identified or accommodated through bureaucratic processes which govern research ethics. We advance the notion of research ethics as an ongoing process that requires researcher skills and engagement, rather than one where it is a one off bureaucratic exercise.
Resumo:
Competition between microbial species is a product of, yet can lead to a reduction in, the microbial diversity of specific habitats. Microbial habitats can resemble ecological battlefields where microbial cells struggle to dominate and/or annihilate each other and we explore the hypothesis that (like plant weeds) some microbes are genetically hard-wired to behave in a vigorous and ecologically aggressive manner. These 'microbial weeds' are able to dominate the communities that develop in fertile but uncolonized - or at least partially vacant - habitats via traits enabling them to out-grow competitors; robust tolerances to habitat-relevant stress parameters and highly efficient energy-generation systems; avoidance of or resistance to viral infection, predation and grazers; potent antimicrobial systems; and exceptional abilities to sequester and store resources. In addition, those associated with nutritionally complex habitats are extraordinarily versatile in their utilization of diverse substrates. Weed species typically deploy multiple types of antimicrobial including toxins; volatile organic compounds that act as either hydrophobic or highly chaotropic stressors; biosurfactants; organic acids; and moderately chaotropic solutes that are produced in bulk quantities (e.g. acetone, ethanol). Whereas ability to dominate communities is habitat-specific we suggest that some microbial species are archetypal weeds including generalists such as: Pichia anomala, Acinetobacter spp. and Pseudomonas putida; specialists such as Dunaliella salina, Saccharomyces cerevisiae, Lactobacillus spp. and other lactic acid bacteria; freshwater autotrophs Gonyostomum semen and Microcystis aeruginosa; obligate anaerobes such as Clostridium acetobutylicum; facultative pathogens such as Rhodotorula mucilaginosa, Pantoea ananatis and Pseudomonas aeruginosa; and other extremotolerant and extremophilic microbes such as Aspergillus spp., Salinibacter ruber and Haloquadratum walsbyi. Some microbes, such as Escherichia coli, Mycobacterium smegmatis and Pseudoxylaria spp., exhibit characteristics of both weed and non-weed species. We propose that the concept of nonweeds represents a 'dustbin' group that includes species such as Synodropsis spp., Polypaecilum pisce, Metschnikowia orientalis, Salmonella spp., and Caulobacter crescentus. We show that microbial weeds are conceptually distinct from plant weeds, microbial copiotrophs, r-strategists, and other ecophysiological groups of microorganism. Microbial weed species are unlikely to emerge from stationary-phase or other types of closed communities; it is open habitats that select for weed phenotypes. Specific characteristics that are common to diverse types of open habitat are identified, and implications of weed biology and open-habitat ecology are discussed in the context of further studies needed in the fields of environmental and applied microbiology.
Resumo:
A dynamic food-web model of more than 1000 species was used to quantify the recovery trajectory of marine community size-structure under different hypothetical fishing regimes, using the Northeast Atlantic as an example. Size-structure was summarised by four indicators: the Large Fish Indicator (LFI), the Large Species Indicator (LSI), the biomass-weighted mean maximum length of fish species (EMBED Equation.3) and the biomass-weighted mean maturation length of fish species (EMBED Equation.3). Time-series of these indicators recorded recovery following release from fishing with various size-selectivities, intensities and durations. In model simulations, fishing-induced trophic cascades were observed to distort fish community size-structure, but these did not have a large influence on recovery level or duration as measured by the four indicators. However, simulations showed that local extinctions of large fish species increased in number with both fishing intensity and duration, and could strongly limit the recovery level. Recovery of fish community size-structure to near equilibrium frequently took multiple decades in simulations; these long transient periods suggest that management interventions for size-structure recovery may require much longer than previously thought. Our results demonstrate the need for community-level modelling to set realistic targets for management of community size-structure.
Resumo:
Nursing plays a key role in the coordination and delivery of palliative care services in rural settings. The purpose of this study is to identify barriers and enablers to providing palliative care in rural communities from a nursing perspective. This study utilized a qualitative descriptive design. Findings highlighted that the remoteness, limited access to resources and professional practice barriers created challenges for nurses as they tried to provide quality palliative care to their clients. System-related barriers were identified and included: lack of services, funding issues, and poor continuity of care. Despite these barriers, nurses drew from supports to optimize palliative care such as using a team approach to care, centers, utilizing local case managers and informal community members, and using palliative care resources. These results may help inform policy decisions around the needs of nurses who practice in rural settings to provide quality care to individuals who are dying and their families.