Essay - The role of ecological theory in microbial ecology

Microbial ecology is currently undergoing a revolution, with repercussions spreading throughout microbiology, ecology and ecosystem science. The rapid accumulation of molecular data is uncovering vast diversity, abundant uncultivated microbial groups and novel microbial functions. This accumulation of data requires the application of theory to provide organization, structure, mechanistic insight and, ultimately, predictive power that is of practical value, but the application of theory in microbial ecology is currently very limited. Here we argue that the full potential of the ongoing revolution will not be realized if research is not directed and driven by theory, and that the generality of established ecological theory must be tested using microbial systems.

The relationship of immigrant status to perceptions of reading and reading literacy among young Black students: A test of the Cultural -Ecological Theory of School Performance

This study tests Ogbu and Simons' Cultural-Ecological Theory of School Performance using data from the Progress in International Reading Literacy Study of 2001 (PIRLS), a large-scale international survey and reading assessment involving fourth grade students from 35 countries, including the United States. This theory argues that Black immigrant students outperform their non-immigrant counterparts, academically, and that achievement differences are attributed to stronger educational commitment in Black immigrant families. Four hypotheses are formulated to test this theory: Black immigrant students have (a) more receptive attitudes toward reading; (b) a more positive reading self-concept; and (c) a higher level of reading literacy. Furthermore, (d) the relationship of immigrant status to reading perceptions and literacy persists after including selected predictors. These hypotheses are tested separately for girls and boys, while also examining immigrant students' generational status (i.e., foreign-born or second-generation). ^ PIRLS data from a subset of Black students (N=525) in the larger U.S. sample of 3,763 are analyzed to test the hypotheses, using analysis of variance, correlation and multiple regression techniques. Findings reveal that hypotheses a and b are not confirmed (contradicting the Cultural-Ecological Theory) and c and d are partially supported (lending partial support to the theory). Specifically, immigrant and non-immigrant students did not differ in attitudes toward reading or reading self-concept; second-generation immigrant boys outperformed both non-immigrant and foreign-born immigrant boys in reading literacy, but no differences were found among girls; and, while being second-generation immigrant had a relatively stronger relationship to reading literacy for boys, among girls, selected socio-cultural predictors, number of books in the home and length of U.S. residence, had relatively stronger relationship to reading self-concept than did immigrant status. This study, therefore, indicates that future research employing the Cultural-Ecological Theory should: (a) take gender and generational status into account (b) identify additional socio-cultural predictors of Black children's academic perceptions and performance; and (c) continue to build on this body of evidence-based knowledge to better inform educational policy and school personnel in addressing needs of all children. ^

Context-Based Sound and the Ecological Theory of Perception

This paper aims to investigate the ways in which context-based sonic art is capable of furthering a knowledge and understanding of place based on the initial perceptual encounter. How might this perceptual encounter operate in terms of a sound work’s affective dimension? To explore these issues I draw upon James J. Gibson’s ecological theory of perception and Gernot Böhme’s concept of an ‘aesthetic of atmospheres’. Within the ecological model of perception an individual can be regarded as a ‘perceptual system’: a mobile organism that seeks information from a coherent environment. I relate this concept to notions of the spatial address of environmental sound work in order to explore (a) how the human perceptual apparatus relates to the sonic environment in its mediated form and (b) how this impacts on individuals’ ability to experience such work as complex sonic ‘environments’. Can the ecological theory of perception aid the understanding of how the listener engages with context-based work? In proposing answers to this question, this paper advances a coherent analytical framework that may lead us to a more systematic grasp of the ways in which individuals engage aesthetically with sonic space and environment. I illustrate this methodology through an examination of some of the recorded work of sound artist Chris Watson.

Common psychotic symptoms can be explained by the theory of ecological perception

The symptoms of psychiatric illness are diverse, as are the causes of the illnesses that cause them. Yet, regardless of the heterogeneity of cause and presentation, a great deal of symptoms can be explained by the failure of a single perceptual function – the reprocessing of ecological perception. It is a central tenet of the ecological theory of perception that we perceive opportunities to act. It has also been found that perception automatically causes actions and thoughts to occur unless this primary action pathway is inhibited. Inhibition allows perceptions to be reprocessed into more appropriate alternative actions and thoughts. Reprocessing of this kind takes place over the entire frontal lobe and it renders action optional. Choice about what action to take (if any) is the basis for the feeling of autonomy and ultimately for the sense-of-self. When thoughts and actions occur automatically (without choice) they appear to originate outside of the self, thereby providing prima facie evidence for some of the bizarre delusions that define schizophrenia such as delusional misidentification, delusions of control and Cotard’s delusion. Automatic actions and thoughts are triggered by residual stimulation whenever reprocessing is insufficient to balance automatic excitatory cues (for whatever reason). These may not be noticed if they are neutral and therefore unimportant whereas actions and thoughts with a positive bias are desirable. Responses to negative stimulus, on the other hand, are always unwelcome, because the actions that are triggered will carry the negative bias. Automatic thoughts may include spontaneous positive feelings of love and joy, but automatic negative thoughts and visualisations are experienced as hallucinations. Not only do these feel like they emerge from elsewhere but they carry a negative bias (they are most commonly critical, rude and are irrationally paranoid). Automatic positive actions may include laughter and smiling and these are welcome. Automatic behaviours that carry a negative bias, however, are unwelcome and like hallucinations, occur without a sense of choice. These include crying, stereotypies, perseveration, ataxia, utilization and imitation behaviours and catatonia.

Review article : ecological approach in studying the relation of perception-action : review of the theoretical and empirical data

In daily activities people are using a number of available means for the achievement of balance, such as the use of hands and the co-ordination of balance. One of the approaches that explains this relationship between perception and action is the ecological theory that is based on the work of a) Bernstein (1967), who imposed the problem of ‘the degrees of freedom’, b) Gibson (1979), who referred to the theory of perception and the way which the information is received from the environment in order for a certain movement to be achieved, c) Newell (1986), who proposed that movement can derive from the interaction of the constraints that imposed from the environment and the organism and d) Kugler, Kelso and Turvey (1982), who showed the way which “the degrees of freedom” are connected and interact. According to the above mentioned theories, the development of movement co-ordination can result from the different constraints that imposed into the organism-environment system. The close relation between the environmental and organismic constraints, as well as their interaction is responsible for the movement system that will be activated. These constraints apart from shaping the co-ordination of specific movements can be a rate limiting factor, to a certain degree, in the acquisition and mastering of a new skill. This frame of work can be an essential tool for the study of catching an object (e.g., a ball). The importance of this study becomes obvious due to the fact that movements that involved in catching an object are representative of every day actions and characteristic of the interaction between perception and action.

Networks cities and ecological habitats

As the world’s rural populations continue to migrate from farmland to sprawling cities, transport networks form an impenetrable maze within which monocultures of urban form erupt from the spaces in‐between. These urban monocultures are as problematic to human activity in cities as cropping monocultures are to ecosystems in regional landscapes. In China, the speed of urbanisation is exacerbating the production of mono‐functional private and public spaces. Edges are tightly controlled. Barriers and management practices at these boundaries are discouraging the formation of new synergistic relationships, critical in the long‐term stability of ecosystems that host urban habitats. Some urban planners, engineers, urban designers, architects and landscape architects have recognised these shortcomings in contemporary Chinese cities. The ideology of sustainability, while critically debated, is bringing together thinking people in these and other professions under the umbrella of an ecological ethic. This essay aims to apply landscape ecology theory, a conceptual framework used by many professionals involved in land development processes, to a concept being developed by BAU International called Networks Cities: a city with its various land uses arranged in nets of continuity, adjacency, and superposition. It will consider six lesser‐known concepts in relation to creating enhanced human activity along (un)structured edges between proposed nets and suggest new frontiers that might be challenged in an eco‐city. Ecological theory suggests that sustaining biodiversity in regions and landscapes depends on habitat distribution patterns. Flora and fauna biologists have long studied edge habitats and have been confounded by the paradox that maximising the breadth of edges is detrimental to specialist species but favourable to generalist species. Generalist species of plants and animals tolerate frequent change in the landscape, frequenting two or more habitats for their survival. Specialist species are less tolerant of change, having specific habitat requirements during their life cycle. Protecting species richness then may be at odds with increasing mixed habitats or mixed‐use zones that are dynamic places where diverse activities occur. Forman (1995) in his book Land Mosaics however argues that these two objectives of land use management are entirely compatible. He postulates that an edge may be comprised of many small patches, corridors or convoluting boundaries of large patches. Many ecocentrists now consider humans to be just another species inhabiting the ecological environments of our cities. Hence habitat distribution theory may be useful in planning and designing better human habitats in a rapidly urbanising context like China. In less‐constructed environments, boundaries and edges provide important opportunities for the movement of multi‐habitat species into, along and from adjacent land use areas. For instance, invasive plants may escape into a national park from domestic gardens while wildlife may forage on garden plants in adjoining residential areas. It is at these interfaces that human interactions too flow backward and forward between land types. Spray applications of substances by farmers on cropland may disturb neighbouring homeowners while suburban residents may help themselves to farm produce on neighbouring orchards. Edge environments are some of the most dynamic and contested spaces in the landscape. Since most of us require access to at least two or three habitats diurnally, weekly, monthly or seasonally, their proximity to each other becomes critical in our attempts to improve the sustainability of our cities.

The imprint of the geographical, evolutionary and ecological context on species-area relationships

Species-area relationships (SAR) are fundamental in the understanding of biodiversity patterns and of critical importance for predicting species extinction risk worldwide. Despite the enormous attention given to SAR in the form of many individual analyses, little attempt has been made to synthesize these studies. We conducted a quantitative meta-analysis of 794 SAR, comprising a wide span of organisms, habitats and locations. We identified factors reflecting both pattern-based and dynamic approaches to SAR and tested whether these factors leave significant imprints on the slope and strength of SAR. Our analysis revealed that SAR are significantly affected by variables characterizing the sampling scheme, the spatial scale, and the types of organisms or habitats involved. We found that steeper SAR are generated at lower latitudes and by larger organisms. SAR varied significantly between nested and independent sampling schemes and between major ecosystem types, but not generally between the terrestrial and the aquatic realm. Both the fit and the slope of the SAR were scale-dependent. We conclude that factors dynamically regulating species richness at different spatial scales strongly affect the shape of SAR. We highlight important consequences of this systematic variation in SAR for ecological theory, conservation management and extinction risk predictions.

The ecological niche of Daphnia magna characterized using population growth rate

The concept of an organism's niche is central to ecological theory, but an operational definition is needed that allows both its experimental delineation and interpretation of field distributions of the species. Here we use population growth rate (hereafter, pgr) to de. ne the niche as the set of points in niche space where pgr. 0. If there are just two axes to the niche space, their relationship to pgr can be pictured as a contour map in which pgr varies along the axes in the same way that the height of land above sea level varies with latitude and longitude. In laboratory experiments we measured the pgr of Daphnia magna over a grid of values of pH and Ca2+, and so defined its "laboratory niche'' in pH-Ca2+ space. The position of the laboratory niche boundary suggests that population persistence is only possible above 0.5 mg Ca2+/L and between pH 5.75 and pH 9, though more Ca2+ is needed at lower pH values. To see how well the measured niche predicts the field distribution of D. magna, we examined relevant field data from 422 sites in England and Wales. Of the 58 colonized water bodies, 56 lay within the laboratory niche. Very few of the sites near the niche boundary were colonized, probably because pgr there is so low that populations are vulnerable to extinction by other factors. Our study shows how the niche can be quantified and used to predict field distributions successfully.

What are the policy priorities for sustaining ecological processes? A case study from Victoria, Australia

Developments in ecological theory indicate that ecological processes have major implications for sustaining biodiversity and the provision of ecosystem services. Consequently, conservation actions that focus solely on particular species, vegetation communities, habitats or sites ('assets') are unlikely to be effective over the long term unless the ecological processes that support them continue to function. Efforts to sustain biodiversity must embrace both 'assets' and 'process-oriented' approaches. Existing knowledge about ecological processes, incomplete though it is, has not been adequately considered in government decision making. It is, therefore, necessary to consider how to build consideration of ecological processes into legislative and institutional frameworks, policy and planning processes, and on-ground environmental management. Drawing on insights from interviews, a facilitated workshop, and a literature review, this paper identifies a suite of policy priorities and associated reforms which should assist in ensuring that ecological processes are given more attention in policy-making processes. It is concluded that a multi-pronged approach is required, because there are no 'silver bullets' for sustaining ecological processes.

Multiple threats, or multiplying the threats? Interactions between invasive predators and other ecological disturbances

Invasive species have reshaped the composition of biomes across the globe, and considerable cost is now associated with minimising their ecological, social and economic impacts. Mammalian predators are among the most damaging invaders, having caused numerous species extinctions. Here, we review evidence of interactions between invasive predators and six key threats that together have strong potential to influence both the impacts of the predators, and their management. We show that impacts of invasive predators can be classified as either functional or numerical, and that they interact with other threats through both habitat- and community-mediated pathways. Ecosystem context and invasive predator identity are central in shaping variability in these relationships and their outcomes. Greater recognition of the ecological complexities between major processes that threaten biodiversity, including changing spatial and temporal relationships among species, is required to both advance ecological theory and improve conservation actions and outcomes. We discuss how novel approaches to conservation management can be used to address interactions between threatening processes and ameliorate invasive predator impacts.

A succession of theories : purging redundancy from disturbance theory

The topics of succession and post-disturbance ecosystem recovery have a long and convoluted history. There is extensive redundancy within this body of theory, which has resulted in confusion, and the links among theories have not been adequately drawn. This review aims to distil the unique ideas from the array of theory related to ecosystem change in response to disturbance. This will help to reduce redundancy, and improve communication and understanding between researchers. We first outline the broad range of concepts that have developed over the past century to describe community change in response to disturbance. The body of work spans overlapping succession concepts presented by Clements in 1916, Egler in 1954, and Connell and Slatyer in 1977. Other theories describing community change include state and transition models, biological legacy theory, and the application of functional traits to predict responses to disturbance. Second, we identify areas of overlap of these theories, in addition to highlighting the conceptual and taxonomic limitations of each. In aligning each of these theories with one another, the limited scope and relative inflexibility of some theories becomes apparent, and redundancy becomes explicit. We identify a set of unique concepts to describe the range of mechanisms driving ecosystem responses to disturbance. We present a schematic model of our proposed synthesis which brings together the range of unique mechanisms that were identified in our review. The model describes five main mechanisms of transition away from a post-disturbance community: (i) pulse events with rapid state shifts; (ii) stochastic community drift; (iii) facilitation; (iv) competition; and (v) the influence of the initial composition of a post-disturbance community. In addition, stabilising processes such as biological legacies, inhibition or continuing disturbance may prevent a transition between community types. Integrating these six mechanisms with the functional trait approach is likely to improve the predictive capacity of disturbance theory. Finally, we complement our discussion of theory with a case study which emphasises that many post-disturbance theories apply simultaneously to the same ecosystem. Using the well-studied mountain ash (Eucalyptus regnans) forests of south-eastern Australia, we illustrate phenomena that align with six of the theories described in our model of rationalised disturbance theory. We encourage further work to improve our schematic model, increase coverage of disturbance-related theory, and to show how the model may link to, or integrate with, other domains of ecological theory.

Framework to improve the application of theory in ecology and conservation

Ecological theory often fails applied ecologists in three ways: (1) Theory has little predictive value but is nevertheless applied in conservation with a risk of perverse outcomes, (2) individual theories have limited heuristic value for planning and framing research because they are narrowly focused, and (3) theory can lead to poor communication among scientists and hinder scientific progress through inconsistent use of terms and widespread redundancy. New approaches are therefore needed that improve the distillation, communication, and application of ecological theory. We advocate three approaches to resolve these problems: (1) improve prediction by reviewing theory across case studies to develop contingent theory where possible, (2) plan new research using a checklist of phenomena to avoid the narrow heuristic value of individual theories, and (3) improve communication among scientists by rationalizing theory associated with particular phenomena to purge redundancy and by developing definitions for key terms. We explored the extent to which these problems and solutions have been featured in two case studies of long-term ecological research programs in forests and plantations of southeastern Australia. We found that our main contentions were supported regarding the prediction, planning, and communication limitations of ecological theory. We illustrate how inappropriate application of theory can be overcome or avoided by investment in boundary-spanning actions. The case studies also demonstrate how some of our proposed solutions could work, particularly the use of theory in secondary case studies after developing primary case studies without theory. When properly coordinated and implemented through a widely agreed upon and broadly respected international collaboration, the framework that we present will help to speed the progress of ecological research and lead to better conservation decisions.

Wellness education : an integrated theoretical framework for fostering transformative learning

Optimum Wellness involves the development, refinement and practice of lifestyle choices which resonate with personally meaningful frames of reference. Personal transformations are the means by which our frames of reference are refined across the lifespan. It is through critical reflection, supportive relationships and meaning making of our experiences that we construct and reconstruct our life paths. When individuals are able to be what they are destined to be or reach their higher purpose, then they are able to contribute to the world in positive and meaningful ways. Transformative education facilitates the changes in perspective that enable one to contemplate and travel a path in life that leads to self-actualisation. This thesis argues for an integrated theoretical framework for optimum Wellness Education. It establishes a learner centred approach to Wellness education in the form of an integrated instructional design framework derived from both Wellness and Transformative education constructs. Students’ approaches to learning and their study strategies in a Wellness education context serve to highlight convergences in the manner in which students can experience perspective transformation. As they learn to critically reflect, pursue relationships and adapt their frames of reference to sustain their pursuit of both learning and Wellness goals, strengthening the nexus between instrumental and transformative learning is a strategically important goal for educators. The aim of this exploratory research study was to examine those facets that serve to optimise the learning experiences of students in a Wellness course. This was accomplished through three research issues: 1) What are the relationships between Wellness, approaches to learning and academic success? 2) How are students approaching learning in an undergraduate Wellness subject? Why are students approaching their learning in the ways they do? 3) What sorts of transformations are students experiencing in their Wellness? How can transformative education be formulated in the context of an undergraduate Wellness subject? Subsequent to a thorough review of the literature pertaining to Wellness education, a mixed method embedded case study design was formulated to explore the research issues. This thesis examines the interrelationships between student, content and context in a one semester university undergraduate unit (a coherent set of learning activities which is assigned a unit code and a credit point value). The experiences of a cohort of 285 undergraduate students in a Wellness course formed the unit of study and seven individual students from a total of sixteen volunteers whose profiles could be constructed from complete data sets were selected for analysis as embedded cases. The introductory level course required participants to engage in a personal project involving a behaviour modification plan for a self-selected, single dimension of Wellness. Students were given access to the Standard Edition Testwell Survey to assess and report their Wellness as a part of their personal projects. To identify relationships among the constructs of Self-Regulated Learning (SRL), Wellness and Student Approaches to Learning (SAL) a blend of quantitative and qualitative methods to collect and analyse data was formulated. Surveys were the primary instruments for acquiring quantitative data. Sources included the Wellness data from Testwell surveys, SAL data from R-SPQ surveys, SRL data from MSLQ surveys and student self-evaluation data from an end of semester survey. Students’ final grades and GPA scores were used as indicators of academic performance. The sources of qualitative data included subject documentation, structured interview transcripts and open-ended responses to survey items. Subsequent to a pilot study in which survey reliability and validity were tested in context, amendments to processes for and instruments of data collection were made. Students who adopted meaning oriented (deep/achieving) approaches tended to assess their Wellness at a higher level, seek effective learning strategies and perform better in formal study. Posttest data in the main study revealed that there were significant positive statistical relationships between academic performance and total wellness scores (rs=.297, n=205, p<.01). Deep (rs=.343, n=137, p<.01) and achieving (rs=.286, n=123, p<.01) approaches to learning also significantly correlated with Wellness whilst surface approaches had negative correlations that were not significant. SRL strategies including metacognitive selfregulation, effort, help-seeking and critical thinking were increasingly correlated with Wellness. Qualitative findings suggest that while all students adopt similar patterns of day to day activities for example attending classes, taking notes, working on assignments the level of care with which these activities is undertaken varies considerably. The dominant motivational trigger for students in this cohort was the personal relevance and associated benefits of the material being learned and practiced. Students were inclined to set goals that had a positive impact on affect and used “sense of happiness” to evaluate their achievement status. Students who had a higher drive to succeed and/or understand tended to have or seek a wider range of strategies. Their goal orientations were generally learning rather than performance based and barriers presented a challenge which could be overcome as opposed to a blockage which prevented progress. Findings from an empirical analysis of the Testwell data suggest that a single third order Wellness construct exists. A revision of the instrument is necessary in order to juxtapose it with the chosen six dimensional Wellness model that forms the foundation construct in the course. Further, redevelopment should be sensitive to the Australian context and culture including choice of language, examples and scenarios used in item construction. This study concludes with an heuristic for use in Wellness education. Guided by principles of Transformative education theory and behaviour change theory, and informed by this representative case study the “CARING” heuristic is proposed as an instructional design tool for Wellness educators seeking to foster transformative learning. Based upon this study, recommendations were made for university educators to provide authentic and personal experiences in Wellness curricula. Emphasis must focus on involving students and teachers in a partnership for implementing Wellness programs both in the curriculum and co-curricularly. The implications of this research for practice are predicated on the willingness of academics to embrace transformative learning at a personal level and a professional one. To explore students’ profiles in detail is not practical however teaching students how to guide us in supporting them through the “pain” of learning is a skill which would benefit them and optimise the learning and teaching process. At a theoretical level, this research contributes to an ecological theory of Wellness education as transformational change. By signposting the wider contexts in which learning takes place, it seeks to encourage changing paradigms to ones which harness the energy of each successive contextual layer in which students live. Future research which amplifies the qualities of individuals and groups who are “Well” and seeks the refinement and development of instruments to measure Wellness constructs would be desirable for both theoretical and applied knowledge bases. Mixed method Wellness research derived and conducted by teams that incorporate expertise from multiple disciplines such as psychology, anthropology, education, and medicine would enable creative and multi-perspective programs of investigation to be designed and implemented. Congruences and inconsistencies in health promotion and education would provide valuable material for strengthening the nexus between transformational learning and behaviour change theories. Future development of and research on the effectiveness of the CARING heuristic would be valuable in advancing the understanding of pedagogies which advance rather than impede learning as a transformative process. Exploring pedagogical models that marry with transformative education may render solutions to the vexing challenge of teaching and learning in diverse contexts.

Mothers of young children with special health care needs : maternal well-being and engagement in work

This thesis reports research focused on the well-being and employment experiences of mothers who have a child with special health care needs. Data are drawn from Growing Up in Australia: The Longitudinal Study of Australian Children (LSAC). This is a public access database. The thesis uses the social ecological theory of Bronfenbrenner (1984) and the work of Zubrick et al. (2000) on human and social capital to inform the conceptual framework developed for the research. Four studies are reported. LSAC has a nationally representative sample of Australian children and their families. The study is tracking the development of 10,000 children, with data collected every two years, from 2004 to 2018. This thesis uses data from the Kindergarten Cohort of LSAC. The 4,983 children in the Kindergarten Cohort were aged 4 years at recruitment into the study in 2004. The analyses in this thesis use child and family data from Wave 1 (2004) and Wave 2 (2006) for a subsample of the children who are identified as having special health needs. This identification is based on a short screening questionnaire included in the Parent 1 Interview at each wave of the data collection. It is the children who are identified as having special health care needs which can be broadly defined as chronic health conditions or developmental difficulties. However, it is the well-being and employment experiences of the mothers of these children that are the primary focus in three of the four studies reported in this thesis.