428 research outputs found
Interactive effects of losing key grazers and ecosystem engineers vary with environmental context
No full textLoss of biodiversity may cause significant changes to ecosystem structure and functioning. Evidence from long-term in situ removal experiments is rare but important in determining the effects of biodiversity loss against a background of environmental variation. Limpets and mussels are thought to be important in controlling community structure on wave-exposed shores in the UK: limpets as key grazers, mussels as ecosystem engineers. A long-term factorial removal experiment revealed interactive effects that varied between 2 shores in SW England. At one site (Harlyn), removing limpets caused a significant shift in community structure, but where limpets were lost, the presence or absence of mussels made little difference. Where limpets were present, however, the removal of mussels changed the structure and variability of the community. At the other site (Polzeath), the loss of mussels caused significant changes in community structure, and limpets played a less important role. At Harlyn, fucoid algae were abundant throughout the year. There were fewer algae at Polzeath, and cover was dominated by the summer bloom of ephemerals. At Harlyn, the limpets played a major role in controlling algae, but their effects were mediated by the presence of mussels. Other grazers were not able to fulfil their role. At Polzeath, mussels were far more important, and ephemeral algae grew on them regardless of the presence or loss of limpets. These findings emphasise the need to assess spatial and temporal variation in the effects of biodiversity loss and the importance of interactive effects of loss of multiple species from different functional groups
Responding to Literature Through Student–Author Interviews: Eighth-Grade Students Challenge Chris Crowe’s Mississippi Trial, 1955
No full textThis study explores virtual, student–author interviews eighth-grade students led with Chris Crowe in response to his young adult novel Mississippi Trial, 1955. The opportunity to interview the author motivated students to read the novel. Through their text-world development, students connected with the fictional and nonfictional characters, Hiram Hillburn and Emmett Till, respectively. Through their critical reader-responses, students sought truth about Emmett Till’s case as they questioned Crowe about the choices he made as an author and researcher, which supported students’ understanding of character development and historical significance of Emmett Till’s case. Crowe’s answers to the students’ critical questions were not easy, but through the student–author interview preparation and implementation process, participants captured a shared understanding of Emmett Till’s case and how its connection to the U.S. civil rights movement impacted history and is pertinent today. Ultimately, this article advocates for reader-response pedagogy to include virtual or in-person student–author interviews
A transpersonal model of music therapy: Deepening practice (Crowe)
No full textThis is a review of the book "A transpersonal model of music therapy: Deepening practice" authored by Barbara Crowe.
Title: A transpersonal model of music therapy: Deepening practice Author: Barbara Crowe Publication year: 2017 Publisher: Barcelona Publishers Pages: 218 ISBN: 978194541126
Catherine Crowe: Gender, Genre, and Radical Politics
No full textThis is the first full-length study of the popular Victorian writer Catherine Crowe (1790–1872). Crowe is increasingly being recognised as an important and influential figure in the literary and Spiritualist circles of the nineteenth century. This monograph offers a reassessment of her major works, arguing that her writing was prescient. Best known today for her collection of “real” ghost tales The Night Side of Nature: Or Ghosts and Ghost Seers, Crowe also wrote five popular novels, as well as numerous short stories and essays. Innovative and sometimes original in their use of genre, her works covered the Newgate genre, helped to
initiate detective fiction, included elements of the social problem novels of the 1840s, and pointed the way to the Sensation novels of the 1860s.
Politically radical in many ways, Crowe was vocal about women’s oppression by men, social inequality, poverty, slavery, and animal rights.
This volume aims to restore an author who was once famous and lauded to her proper place in the scholarly discussion of Victorian literature
Taxonomy, phylogenetic and biogeographical relationships of African grassland Francolins (Genus: Scleroptila)
No full textBibliography: leaves 23-28.The potential for using a combination of molecular and whole-organismal data has opened up new avenues for avian taxonomy, phylogenetics and biogeography. Such a multifaceted approach is used here to identify diagnosable taxa within the Orange River Francolin Scleroptila levaillanloides species complex and resolve evolutionary relationships between these taxa and other mono-and polytypic forms within the Red-winged Group of francolins (= genus Scleroplila sensli lalo). Mitochondrial cytochrome-b DNA sequence data (±250 b.p.) from 50 individuals and 19 morphological characters extracted from reports in published literature were employed to achieve these aims. These characters were analysed separately and also in combination using maximum parsimony (DNA sequences and organismal data), maximum likelihood (DNA sequences) and distance (DNA sequences) analyses. Monophyly of the Red-winged Group plus the Ring-necked Francolin Dendroperdix slreptophorus was supported by all the analyses (bootstrap support ranged from 50%-94%) except distance analysis. The Orange River Francolin complex was found to be non-monophyletic. Two distinct clades were identified, one comprising taxa from southwestern and the other from northeastern Africa. Morphological analysis yielded a distinct clade of the southwestern Orange River Francolin. The other polytypic species and assemblages thereof show poor resolution. The results of this study clearly demonstrate a need for further assessment of the taxonomic status of Scleroptila spp. and their phylogenetic relationships
The Night Side of Nature
No full textThe novelist and children's author Catherine Crowe (c.1800–1876) published The Night Side of Nature in two volumes in 1848. This lively collection of ghostly sketches and anecdotes was a Victorian best-seller and Crowe's most popular work. Sixteen editions appeared in six years, and it was translated into several European languages. The stories are intertwined with Crowe's own interpretations and commentaries which attack the scepticism of enlightenment thought and orthodox religion. Crowe seeks instead to encourage and re-invigorate a sense of wonder and mystery in life by emphasising the supernatural. The stories in Volume 1 centre on dreams, psychic presentiments, traces, wraiths, doppelgängers, apparitions, and imaginings of the after-life. Crowe's vivid tales, written with great energy and imagination, are classic examples of nineteenth-century spiritualist writing and strongly influenced other authors as well as providing inspiration for later adherents of ghost-seeing and psychic culture.</jats:p
The Night Side of Nature
No full textThe novelist and children's author Catherine Crowe (c.1800–1876) published The Night Side of Nature in two volumes in 1848. This lively collection of ghostly sketches and anecdotes was a Victorian best-seller and Crowe's most popular work. Sixteen editions appeared in six years, and it was translated into several European languages. The stories are intertwined with Crowe's own interpretations and commentaries which attack the scepticism of enlightenment thought and orthodox religion. Crowe seeks instead to encourage and re-invigorate a sense of wonder and mystery in life by emphasising the supernatural. Volume 2 probes the mysterious phenomena of troubled spirits, haunted houses, spectral lights, apparitions and poltergeists. Crowe's vivid tales, written with great energy and imagination, are classic examples of nineteenth-century spiritualist writing and strongly influenced other authors, including Charles Baudelaire, as well as providing inspiration for later adherents of ghost-seeing and psychic culture.
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Complexity affects habitat preference and predation mortality in postlarval Penaeus plebejus: implications for stock enhancement
No full textGlobal attempts to offset declines in fishery populations through stock enhancement have had varied levels of success due to the absence of preliminary studies to determine which habitats best support release species and the mechanisms controlling their distribution. Habitat preference was examined as a possible mechanism driving distribution of postlarval Penaeus plebejus, a current candidate prawn for stock enhancement in Australia. Occupancy of complex (artificial macrophyte) and simple (bare sand and mud) habitats by postlarvae was compared in the presence and absence of a choice between the habitats. Predation mortality was also compared amongst these habitats. P. plebejus settled into the different habitats randomly during the night, but actively selected macrophyte over the simple habitats during the day. Mortality caused by the predatory fishes Centropogan australis and Acanthopagrus australis was higher in simple habitats than in complex habitats, but was similar across habitats when large penaeid prawns, Metapenaeus macleayi (which are tactile rather than visual feeders), were used as predators. Postlarvae may select macrophyte habitats during the day to lower predation risk, but because nighttime foraging efficiency is reduced in their predators, which are primarily visual hunters, this may preclude the need of postlarvae to obtain shelter in macrophyte habitats at night. Predation mortality of stocked P. plebejus may be minimized by releasing postlarvae directly into macrophyte habitats. Studies such as these must precede all stock enhancement attempts because they identify optimal release strategies and allow ecological and financial costs of enhancement to be weighed against projected benefits, and thereby assess the practicality of enhancement as a management option
Conclusions
No full textMarine ecosystems provide a range of essential benefits to society, including food and other products, waste assimilation, coastal protection and climate regulation as well as less tangible, but no less important cultural and aesthetic benefits (Chapter 2). To a considerable degree, those benefits are underpinned by ecosystem services dependent on the efficient functioning of the ecosystems, although detailed understanding of relationships between particular services and particular functional processes is currently being developed (Chapter 2). In turn, the efficient functioning of ecosystems has been linked to the number and identity of species present, as well as the prevailing environmental conditions (Chapter 5).
Society derives many of its benefits from ecosystems via sectoral activities and industries, such as fishing, construction, energy, shipping, leisure and tourism. These activities can impose pressures on ecosystems, such as removal of biomass, inputs of nutrients and other contaminants and the introduction of artificial structures and non-indigenous species (Chapter 3). Such pressures act through a range of mechanisms affecting different levels of biological organisation to modify biodiversity and ecosystem functioning (Chapters 3 and 4). The chapters in this book have reviewed current knowledge of how the spectrum of human activities and pressures (collectively referred to as stressors) affect biodiversity, ecosystem functioning and the provision of services and benefits to society. A key objective was to provide a synthesis of evidence for policy makers and managers to facilitate trade-offs between sectors of activity based on the benefits they provide weighed against the degree to which they may compromise the delivery of ecosystem services now and into the future (see Chapter 11).
In this chapter, we first synthesise and summarise the inferences presented in the book about the range of impacts of different activities and pressures on biodiversity and ecosystem processes. We then ask how this kind of knowledge can help policy makers and managers, particularly in the achievement of the international targets laid down in the Millennium Development Goals (Chapter 1) and whether the ecosystem approach and the concept of ecosystem services can provide an effective framework for facilitating the achievement of those goals.No Full Tex
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