1,721,367 research outputs found
Agriculture, biodiversity and markets
No full text[Extract] It is widely accepted that the sustainability of the global ecosystem in general, and of agriculture in particular, is dependent on the preservation, enhancement, and exploitation of biological diversity. Biological diversity - both wild and cultivated - underwrites the sustainability of agricultural production through the provision of the raw genetic material needed to drive innovation and adaptation, and through the provision of ecosystem processes and services that play important functional roles in agricultural systems. Agricultural biodiversity - or agrobiodiversity - plays a pivotal role in the livelihoods of all farmers regardless of resource endowment or geographical location. It provides the basic resources farmers need to adapt to varying conditions in marginal environments and the resources required to increase productivity in favourable areas. Clearly, there is a very close relationship between biodiversity and the livelihoods and well-being of agricultural communities. The need to protect and enhance agricultural biodiversity seems obvious. But what exactly does it meant to protect and enhance agricultural biodiversity? And how is this best achieved? As compelling as the case for agrobiodiversity may appear, these seemingly simple and straightforward questions demand complex and wide-ranging answers
Agrobiodiversity and sustainable farm livelihoods: policy implications and imperatives
No full text[Extract] Our objective in this chapter is to distil some of the broad policy implications of research into the relationships between agriculture, biodiversity and markets. To place these observations in some sort of context, it is important to note that quite apart from the variance in social, political, economical and agroecological conditions faced by relevant policy-making and regulatory institutions around the world (variance that would make highly specific recommendations largely redundant), prior to the 1980s the terms biological diversity and biodiversity were largely unheard of. Before the early 1990s, they were not on the international radar - agricultural biodiversity even less so (see Hannigan, 1995; Escobar, 1998). This is not to say that declines in biodiversity prior to the 1990s were too insignificant to generate awareness or action. Nor that various aspects of biodiversity were not subject to intentional management by farmers and rural communities, investigation by scientific agencies, campaigning by NGOs and/or intervention by governments. In fact, unlike other global environmental issues such as ozone depletion and anthropogenically-induced climate change that were largely unknown before the late 20th century, considerable efforts had been made for some time to protect native species and ecosystems, to farm in ways that enhance soil biota, and to conserve and exploit the genetic diversity of important food plants and animals
The human ecology of agrodiversity
No full text[Extract] In coming to deal with the place of food production in industrial societies we face a set of strong tensions. There is the productivist view of agriculture as a technical problem of how best to exploit particular biophysical structures and functions to produce the maximum amount of useable food and fibre. Set against this is a spectrum of views of agriculture as a socio-cultural activity that all but defines a particular society or nation, farming as a way of life, through to it being seen as a key agent of economic development. Riding uneasily with all these is the growing understanding of the place of agriculture as the dominant form of human land management on the planet that must account for many landscape functions and processes other than just providing for human needs. We need a framework for understanding agriculture in all its complex roles of providing human sustenance and cultural meanings, as well as delivering ecosystems services
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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