1,721,037 research outputs found
Conceptualizing pathways to sustainable agricultural intensification
Full text linkThere is widespread consensus among scientists, policy makers, and practitioners that agriculture should become more sustainable, while maintaining the ability to meet future food demand. However, there are still many diverging views on what sustainable intensification means, and how to get there. In this article, we present a conceptual framework to navigate agricultural intensification pathways. The conceptual framework aligns three research themes central to improving the sustainability of agriculture: (1) What are the social, economic, and environmental trade-offs of alternative agricultural intensification options? (2) How do land managers decide on intensification strategies, and how can the adoption of sustainable practices be made more attractive? (3) How do socio-political, technological, and environmental mega-trends and other drivers of change affect sustainable intensification measures and agricultural landscapes? The framework presented here goes beyond earlier frameworks by considering multiple dimensions of intensity and sustainability, drawing from both natural and social science theories. Also, it operates across spatial and temporal scales, and is outcome-focused while explicitly considering the linkages between decision making processes and sustainability outcomes. We argue that given these novelties the conceptual framework can serve as a blueprint to assess pathways towards sustainable agricultural intensification
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
Mind the gaps: What do we know about how multiple chemical stressors impact freshwater aquatic microbiomes?
No full textFreshwaters are critical to human survival and well-being. However, over-reliance on freshwaters has made them among the most threatened ecosystems in the world. Freshwaters also connect terrestrial and marine ecosystems, making them a melting pot for anthropogenic stressors, in-particular agricultural and urban runoff containing chemical and nutrient pollution. Many of the ecosystem services provided by freshwaters are directly or indirectly supported by microorganisms, which form the basal layer of aquatic food webs, drive nitrogen fixation, oxygen production, and nutrients cycling. Yet the effects of multiple interacting stressors on microbial populations and communities is poorly understood and rarely considered in policy development. Here, we evaluate the current state of knowledge around how key anthropogenic stressors, pesticide and antibiotic pollution, affect freshwater microbiomes. Based on their concentrations in EU rivers and prevalence in agriculture, we review freshwater microbial community responses to eight selected chemicals pollutants: glyphosate, diflufenican, oxytetracycline, amoxicillin, metaldehyde, imidacloprid, tebuconazole, and chlorothalonil. We focused on mesocosm-based studies as these balance environmental realism and experimental control, providing mechanistic insights into ecological effects. Our review revealed a systematic bias towards a limited selection of chemicals, studied in isolation, on a subset of microbial taxa. For example, studies focussing on glyphosate represent approximately ⅓ of all the relevant publications identified, while other prevalent chemical pollutants such as metaldehyde, chlorothalonil, and diflufenican are ignored. More research is urgently needed to fill this gap, especially studies investigating the interacting effects of chemical mixtures with other anthropogenic stressors, for example nutrient pollution and climate change. We propose a move away from the over-simplistic study of chemical pollutants towards a research agenda that incorporates more realistic scenarios and comprehensive biomonitoring combining taxonomic and trait-based information
The challenges of linking ecosystem services to biodiversity : lessons from a large-scale freshwater study
No full textWe explore some of the key challenges and opportunities that lie in assessing the role of freshwater biodiversity in sustaining ecosystem services, using the recent large interdisciplinary NERC-DURESS project (www.nerc-DURESS.org) as an exemplar case study of wider issues. The conceptual and methodological challenges raised are identified, explored and a range of methods are proposed to quantify how freshwater ecoservices, such as fish production or water quality regulation, depend on river organisms, and how we might identify biodiversity thresholds under which a service is likely to be compromised. We conclude that interdisciplinary, large scale, in situ approaches like these are needed to (i) fully understand how river biodiversity sustains ecosystem services; (ii) help evaluate if, where, and how the ecosystem approach can benefit long-term resource management and (iii) maximise impacts on policy, practice and decision making, which can be especially effective where strong ‘co-production’ partnerships with a broad range of stakeholders are developed and nurtured from a project's outset
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