877 research outputs found
The Effect of Dispersed Oil on the Calcification Rate of the Reef-Building Coral Diploria Strigosa
Hermatypic corals represent environmentally and economically important components of the reef ecosystem. Oil spills and clean-up operations in reef areas are potential sources of pollution impact. This paper presents an evaluation of the calcification rate of specimens of the reef-building coral Diploria strigosa in response to 24 hour treatments of chemically dispersed oil at concentrations of 20 ppm. The concentrations and durations were chosen to represent a scenario of a short-term oil spill treated with dispersant passing over a coral reef.
Calcification rates were determined by the buoyant weight technique at several day intervals for up to 29 days following treatment. Results from laboratory experiments (Winter and Summer) conducted in a flow-through seawater system indicate that treated corals, both in comparison to untreated controls as well as to their pretreatment rates, experienced no depression in calcification.
In contrast, a possible short-term enhancement of calcification for the treated corals was observed
Effects of a Dispersed and Undispersed Crude Oil on Mangroves, Seagrasses and Corals
The primary objective of this study was to evaluate the application of dispersant to spilled oil as a means of reducing adverse environmental effects of oil spills in nearshore, tropical waters. The results of numerous laboratory and field studies have suggested that dispersants may play a useful role in reducing adverse impacts on sensitive and valued environments such as mangroves, seagrasses, and corals. However, the use of dispersants has not been allowed thus far in most situations because of a lack of direct experimental data on the various effects of dispersants and the environmental trade-offs presumed to occur as a result of their application to crude oils. To accomplish this objective, a 21/2- year field experiment was designed in which detailed, synoptic measurements and assessments were made of representative intertidal and nearshore subtidal habitats and organisms (man-groves, seagrass beds, and coral reefs) before, during, and after exposure to untreated crude oil and chemically dispersed oil. The results were in-tended to give guidance in minimizing the ecological impacts of oil spills through evaluation of trade-offs in the relative impacts of chemical dispersion to tropical marine intertidal and subtidal habitats
Interview of Christine Sleeter on Multicultural Education: Past, Present, and Key Future Directions
This is an interview of Christine Sleeter on her work in multicultural education over four decades. Links to videos of this interview are available in the Appendix after the references. Transcriptions and videos of Dr. Sleeter’s interview provide plain-spoken content for teacher educators, school administrators, and teachers interested in advancing multicultural education and its critical and practical translation into public school classrooms. The main topics covered in this interview are: (a) the “origins” of multicultural education, (b) the basics of multicultural teaching in student and community relationships, (c) advice for new teachers coming into the profession, (d) discussions of White racism and what White teachers can do, and (e) the new social movement on ethnic studies curriculum. Broadly speaking, this interview provides a plain-spoken account of multicultural education’s past, present, and key future directions from Christine Sleeter, one of the field’s founding and most committed members
Employing culturally responsive pedagogy to foster literacy learning in schools
In recent years it has become increasingly obvious that, to enable students in schools from an increasingly diverse range of cultural backgrounds to acquire literacy to a standard that will support them to achieve academically, it is important to adopt pedagogy that is responsive to, and respectful of, them as culturally situated. What largely has been omitted from the literature, however, is discussion of a relevant model of learning to underpin this approach. For this reason this paper adopts a socio-cultural lens (Vygotsky, 1978) through which to view such pedagogy and refers to a number of seminal texts to justify of its relevance. Use of this lens is seen as having a particular rationale. It forces a focus on the agency of the teacher as a mediator of learning who needs to acknowledge the learner’s cultural situatedness (Kozulin, 2003) if school literacy learning for all students is to be as successful as it might be. It also focuses attention on the predominant value systems and social practices that characterize the school settings in which students’ literacy learning is acquired. The paper discusses implications for policy and practice at whole-school, classroom and individual student levels of culturally-responsive pedagogy that is based on a socio-cultural model of learning. In doing so it draws on illustrations from the work of a number of researchers, including that of the author
A theory of motivation and ontological enhancement: the role of disability policy in student empowerment and institutional change
As debate continues around the nature and values of education, it is important to ask the question of what factors motivate a student to engage with the ends of an educational institution. In this paper, a broad, holistic view of learner motivation, derived from Aristotelian ethics, is used to provide a model to drive institutional change.
Focussing on the approach of one Higher Education institution to the particular accommodations required for students with disabilities, the paper identifies three factors which motivate students, a failure to engage with the aims and ends of the educational project, a failure to see that a particular learning aim is worth attaining, and a simple lack of will‐power to attain it. To each of these failures a social cause is identified, and a change in both the institutional culture and the individual learner's approach to their education is suggested
Education policy as an act of white supremacy: whiteness, critical race theory and education reform
The paper presents an empirical analysis of education policy in England that is informed by recent developments in US critical theory. In particular, I draw on ‘whiteness studies’ and the application of Critical Race Theory (CRT). These perspectives offer a new and radical way of conceptualising the role of racism in education. Although the US literature has paid little or no regard to issues outside North America, I argue that a similar understanding of racism (as a multifaceted, deeply embedded, often taken-for-granted aspect of power relations) lies at the heart of recent attempts to understand institutional racism in the UK. Having set out the conceptual terrain in the first half of the paper, I then apply this approach to recent changes in the English education system to reveal the central role accorded the defence (and extension) of race inequity. Finally, the paper touches on the question of racism and intentionality: although race inequity may not be a planned and deliberate goal of education policy neither is it accidental. The patterning of racial advantage and inequity is structured in domination and its continuation represents a form of tacit intentionality on the part of white powerholders and policy makers. It is in this sense that education policy is an act of white supremacy. Following others in the CRT tradition, therefore, the paper’s analysis concludes that the most dangerous form of ‘white supremacy’ is not the obvious and extreme fascistic posturing of small neonazi groups, but rather the taken-for-granted routine privileging of white interests that goes unremarked in the political mainstream
Modelling regional land change scenarios to assess land abandonment and reforestation dynamics in the Pyrenees (France)
International audienceOver the last decades and centuries, European mountain landscapes have experienced substantial transformations. Natural and anthropogenic LULC changes (land use and land cover changes), especially agro-pastoral activities, have directed influenced the spatial organization and composition of European mountain landscapes. For the past 60 years, natural reforestation has been occurring due to a decline in both agricultural production activities and rural population. Stakeholders, to better anticipate future changes, need spatially and temporally explicit models to identiy areas at risk of land change and possible abandonment. This paper presents an integrated approach combining forecasting scenarios and a LULC changes simulation model to assess where LULC changes may occur in the Pyrenees Mountains, based on historical LULC trands and a range of future socio-economic drivers. The proposed methodology considers local specificities of Pyrenan valleys, sub-regional climate and topographical properties, and regional economic policies. Results indicate that some regions are projected to face strong abandonment, regardless of scenario conditions. Overall, high rates of change are associated with administrative regions where land productivity is highly dependent on socio-economic drivers and climatic and environmental conditions limit intensive (agricultural and/or pastoral) production and profitability. The combination of the results for the four scenarios allows assessements of where encroachment (e.g. colonization by shrublands) and reforestation are the most probable. This assessment intends to provide insight into the potential future development of the Pyrenees to help identify areas that are the most sensitive to change and to guide decision makers to help their management decisions
'Family comes in all forms, blood or not': disrupting dominant narratives around the patriarchal nuclear family
After nearly 25 years of democracy, lives of young South Africans are
still profoundly shaped by the legacies of apartheid. This paper
considers how these differences are produced, maintained and
disrupted through an exploration of changing narratives
developed by a small group of South African pre-service teachers,
with a particular focus on the narratives developed around
discourses of fatherhood generally and absent fathers in
particular. We draw on interviews conducted with three students
in which we discussed their digital stories and literature reviews.
In this paper, we draw attention to the limitations of digital
storytelling and the risks such autobiographical storytelling
presents of perpetuating dominant narratives that maintain and
reproduce historical inequalities. At the same time, in highlighting
ways in which this risk might be confronted, the paper also aims
to show the possibilities in which these dominant narratives may
be challenged.IBS
The Effects of Oil and Oil Dispersants on the Skeletal Growth of the Hermatypic Coral Diploria strigosa
Specimens of the hermatypic coral species Diploria strigosa were exposed to various concentrations (1–50 ppm) of oil or oil plus dispersant for 6–24 h periods in four laboratory and two field experiments. After dosing, corals were transplanted to, or left in, the field and recollected approximately one year later for extension (linear) growth analysis by the alizarin stain method. The experiments were designed to assess the long-term effects of brief low-level concentrations of chemically dispersed oil and oil alone on corals in a situation, for example, where an oil slick (treated and non-treated with dispersants) passes over a reef. No significant differences between extension growth parameters (Septa increase, Columella increase) and a calical shape parameter (New Endotheca Length) of treated corals versus controls were found in any of the experiments. In two summer experiments calical relief (Fossa length) was found to be depressed in corals of some of the experimental treatments
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