1,387 research outputs found
Coexistence and relative abundance in forest trees
No full textContemporary acceleration of biodiversity loss makes increasingly urgent the need to understand the controls of species coexistence1, 2. Tree diversity in particular plays a pivotal role in determining terrestrial biodiversity, through maintaining diversity of its dependent species3, 4 and with them, their predators and parasites. Most theories of coexistence based on the principle of limiting similarity suggest that coexistence of competing species is inherently unstable; coexistence of competitors must be maintained by external forces such as disturbance5, 6, immigration7 or 'patchiness' of resources in space and time8, 9. In contrast, storage theory postulates stable coexistence of competing species through temporal alternation of conditions favouring recruitment of one species over the other10, 11. Here we use storage theory to develop explicit predictions for relative differences between competitors that allow us to discriminate between coexistence models. Data on tree species from a primary forest on the Mexican Pacific coast support a general dynamic of storage processes determining coexistence of similar tree species in this community, and allow us to reject all other theories of coexistence
Global climate and the distribution of plant biomes
No full textBiomes are areas of vegetation that are characterized by the same life-form. Traditional definitions of biomes have also included either geographical or climatic descriptors. This approach describes a wide range of biomes that can be correlated with characteristic climatic conditions, or climatic envelopes. The application of remote sensing technology to the frequent observation of biomes has led to a move away from the often subjective definition of biomes to one that is objective. Carefully characterized observations of life-form, by satellite, have been used to reconsider biome classification and their climatic envelopes. Five major tree biomes can be recognized by satellites based on leaf longevity and morphology: needleleaf evergreen, broadleaf evergreen, needleleaf deciduous, broadleaf cold deciduous and broadleaf drought deciduous. Observations indicate that broadleaf drought deciduous vegetation grades substantially into broadleaf evergreen vegetation. The needleleaf deciduous biome occurs in the world's coldest climates, where summer drought and therefore a drought deciduous biome are absent.Traditional biome definitions are quite static, implying no change in their life-form composition with time, within their particular climatic envelopes. However, this is not the case where there has been global ingress of grasslands and croplands into forested vegetation. The global spread of grasses, a new super-biome, was probably initiated 30-45 Myr ago by an increase in global aridity, and was driven by the natural spread of the disturbances of fire and animal grazing. These disturbances have been further extended over the Holocene era by human activities that have increased the land areas available for domestic animal grazing and for growing crops. The current situation is that grasses now occur in most, if not all biomes, and in many areas they dominate and define the biome. Croplands are also increasing, defining a new and relatively recent component to the grassland super-biome. In the case of both grassland and croplands, various forms of disturbance, particularly frequent disturbance, lead to continued range extensions of the biomes
The language of C.K. Norwid
No full textW niniejszym artykule ukazano różnice między polszczyzną obecną a współczesną C.K. Norwidowi. Autorka skupiła się na rozbieżnościach w zakresie leksyki i gramatyki, tj. fonetyki i fleksji. Materiał źródłowy stanowią utwory pochodzące z tomu Wiersze wybrane w opracowaniu M. Inglota z 1991 roku. Część słownictwa, którym posługiwał się C. Norwid, w dzisiejszych słownikach polszczyzny ogólnej opatrzona jest kwalifikatorami dawne czy przestarzałe. Analiza języka interesujących tekstów wykazuje dużo różnic z obecną polszczyzną także w zakresie fonetyki i fleksji. Stosowane formy są często typowe nie tylko dla XIX, ale także dla XVII czy XVIII wieku.The aim of this article was to present the differences between the present day Polish language and the one used by C.K. Norwid. The author highlighted lexical and grammatical discrepancies, focusing on phonetics and inflection in particular. The source materials were the poems included in the Wiersze wybrane poetry volume, compiled by M. Inglot in 1991. A part of the vocabulary used by Norwid is classified as obsolete or out of date in contemporary dictionaries. Language analysis of the relevant excerpts reveals plenty of differences when confronted with the present day language, also with regards to phonetics and inflection. The forms applied by the poet are typical of the XIXth, as well as XVIIth and XVIIIth century
Identification of specific tree species in ancient semi-natural woodland from digital areal sensor imagery
No full textRemote sensing has great potential as a source of information on tree species. The classification approaches used commonly to extract species information from remotely sensed imagery typically aim to optimize the overall accuracy of species identification, a target which need not satisfy the requirements of a particular user. Often users are interested in a specific species or subset of species, and these may not be accurately identified in a conventional classification. Here, a two-phase classification approach was used to map specific species from aerial sensor imagery of an ancient British woodland. Particular attention was focused on the identification of sycamore since this is displacing the native ash and information on its distribution would enhance basic understanding and management activities. The results show that the classification approach can be adapted to focus on a specific species of interest and used to increase classification accuracy significantly. For example, sycamore was classified to a low accuracy when a conventional approach to classification with a neural network was used (46.6–63.6%, depending on perspective), but the adoption of the two-phase approach increased its accuracy significantly (82.3–93.3%). The results demonstrate the ability to map specific class(es) of interest accurately from remotely sensed imagery. The approach used also highlights the ability to tailor an analysis to the specific requirements of the ecological study in hand and is of broad applicability
Autographed Photo From C.K. Steele to Joseph E. Lowery, April 1980
No full textAn autographed photo of C.K. Steele, Joseph E. Lowery, and Walter E. Fauntroy at a Southern Christian Leadership Conference National Board meeting. The photo is signed by C.K. Steele. The autograph states "Justice With Love - C.K. Steele, Sr.".The Atlanta University Center Robert W. Woodruff Library acknowledges the generous support of the Joseph & Evelyn Lowery Institute for Justice and Human Rights, the Joseph Echols Lowery Irrevocable Trust, and other donors in supporting the processing and digitization of Morehouse College's Joseph Echols and Evelyn Gibson Lowery Collection
New view of strategy: An interview with C.K. Prahalad
No full text'Strategic intent', 'core competence' and 'strategy as stretch and leverage', are all management concepts that have become associated with C.K. Prahalad and his frequent co-author, Gary Hamel, most often in the pages of the Harvard Business Review, but also in other journals and books. These ideas now form the basis of much new thinking about competitiveness by strategic managers. With the publication in 1994 of Competing for the Future, C.K. Prahalad and Gary Hamel create a new view of strategy in one overall statement developing earlier HBR concepts like foresight, strategic architecture, global pre-emption and 'the need to forget'. Then, with new ideas like opportunity space, opportunity horizon, corporate challenge, and expeditionary marketing, the authors present a new language system to capture these ideas. Interviewed in Michigan by EMJ's editor, Paul Stonham, C.K. Prahalad points first that Competing for the Future is about 'democratizing' strategy -- how to engage a large number of people in creating a strategic direction, and that managers are now receptive to exploring ways of revitalizing companies. Continuing of the corporation, profitable growth, and ability to change, are all essential criteria for competitiveness. Wealth creation involves leveraging resources and creating new investment opportunities all the time. Shareholders and investors recognize this. C.K. Prahalad has views on the cultural springs of success, on innate competitive advantage, and on acquisitions as one of a number of alternative modes to acquire competence. He declines to be drawn into a close comparison of large and small companies, but prefers to focus on entrepreneurship and innovation. He points to the decreasing unilateral role of governments in international trade and finance, and to the need for innovative companies to search the global market for managerial talent. Business schools still produce functionally-biased managers; they should concentrate in future on producing at least four skills in their potential managers: teamwork, resolution of complex conflicts, languages, and operationalizing concepts. Finally, hinting in the interview of the next phase of his work, C.K. Prahalad does not lessen the anticipation of his readers.
Investigating spatial structure in specific tree species in ancient semi-natural woodland using remote sensing and marked point pattern analysis
No full textRemote sensing classification has the potential to provide important information, such as tree species distribution maps, to ecologists, at a range of spatial and temporal scales. However, standard classification procedures often fail to provide the high accuracies required for many ecological applications. Previously, a modified remote sensing classification technique was used to provide very high classification accuracies for one
or two classes (e.g. species) of interest. The aim of this paper was to demonstrate that the output from the method can be suitable for spatial ecological analyses, and to provide a generic simulation framework for assessing the adequacy of any given remote sensing classification for such analyses. Marked point pattern analysis (MPPA) was applied to tree species distribution data obtained for sycamore Acer pseudoplatanus and ash
Fraxinus excelsior from a 400 ha ancient semi-natural woodland in southern England using the modified remote sensing classification method to test several hypotheses of ecological interest relating to the spatial distribution and interaction of these species. Monte Carlo simulation methods were then used to evaluate the data and data quality requirements of the MPPA to check that the classified tree species maps for sycamore and ash were adequate. Using the combined method the spatial distributions for sycamore and ash were found to be aggregated and inter-dependent at a range of spatial scales. Together, the remote sensing classification and simulation approaches provide the basis for exploiting more fully the potential of remote sensing to provide information of value to ecologists
Journalistiek oriëntalisme. C.K. Elout en de transformatie van de koloniale verslaggeving in Nederland 1920–1930
No full textIn the interwar period, the leading Dutch journalist C.K. Elout conducted two research trips to the Dutch East Indies for the newspaper Algemeen Handelsblad. This article studies Elout’s letters from his travels in the context of the growing journalistic interest in the Netherlands in colonial matters in the 1920s. The reason for this interest was the increase in information transferred between the Netherlands and South-east Asia as a result of new technologies and rising tensions in the Indies due to the emergence of the anticolonial movement. Through his letters, Elout intended to stimulate colonial reporting in the Netherlands, with the goal of strengthening overseas ties. Therefore, this corpus of texts can be seen as a form of journalistic orientalism in which the author extensively reflects on the differences between the West and the East. This article focuses on these reflections and demonstrates how they influenced Elout’s later commentary on the news from the Dutch East Indies
C.K. McClatchy and Upton Sinclair's EPIC campaign: The Power of the Press in 1934 California
No full textThe media's powerful role in the political process is taken for granted in the 1990s. The California gubernatorial election of 1934, pitting the Socialistturned-Democrat author Upton Sinclair against the RepublicanFrank Merriam and Progressive Raymond Haight, has been frequently suggested by historians to be the forerunner of modern political races influenced so heavily by the mass media. This study focuses on the techniques of the press to subtly and not so subtly subject the political process to the influence of its powerful editors, here represented by C.K. McClatchy of the Sacramento, Fresno, and Modesto Bees.McClatchy's papers provide an interesting control group, in that he appears to have been the only major editor in the state to back the third party candidate, Raymond Haight. Accordingly, in the areas where the Bee was circulated, Haight received his only strong showings and even was victorious in some counties
Jealousies: Mansfield in Mansfield, and the poetry of C.K. Stead
No full textThis paper will consider the character of Katherine Mansfield as portrayed in the novel Mansfield by C.K. Stead (2004), together with the influence of Mansfield on Stead’s poetry. In 1972, Stead was the third recipient of the Katherine Mansfield Memorial Fellowship at Menton, which enabled him to spend eight months in the South of France, working at the Villa Isola Bella, once the home of Katherine Mansfield. During this visit, Stead took the opportunity of re-reading all the Mansfield primary texts published at that time, which led directly to the publication some years later of his Letters and Journals of Katherine Mansfield: A Selection (1977). This immersion in ‘all things Mansfield’ initiated Stead’s fascination with the author, which remains undiminished.
Stead set his novel Mansfield during three years from 1915-1918, a fascinating period in Mansfield’s life when she found her true voice as an author, was still in “reasonably good health”, and which was, as he points out, “the time of her most intense engagement with an extraordinary cast of characters on the English literary scene”. It was also the period of the Great War, which would profoundly affect and influence the lives of Mansfield and her contemporaries. Although technically a work of fiction, since imagination and guess work both, inevitably, play a part, nevertheless Stead’s comprehensive knowledge of Mansfield’s life and literary output, together with his uncanny ability to recreate his characters’ points of view, results in a fascinating novel which has a ring of ‘truth’ about it. The paper will also consider various poems by Stead, including ‘Jealousy 1’ and ‘Jealousy 2’, based on episodes in Mansfield’s life, together with a new poem ‘Isola Bella’, which Stead has written especially for this conferenc
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