1,721,015 research outputs found
Can carbon-trading schemes help to protect China's most diverse forest ecosystems? A case study from Xishuangbanna, Yunnan
No full textXishuangbanna has been largely transformed from biodiverse natural forests and mixed-use farms into monoculture rubber plantations in just twenty years. This conversion has expanded into forests previously protected by the community and onto marginal sites at high-elevation. Market-based ecosystem payments, especially carbon financing, are potential tools to prevent further forest loss in China. Here, we compare rubber net present value (NPV), carbon sequestration, and seed-plant species diversity for Xishuangbanna given three land-use scenarios: Business-As-Usual (BAU), Economic Oriented Scenario (EOS) and Conservation Oriented Scenario (COS) using a previously published spatial map of rubber profitability. The EOS achieved the greatest rubber profit but caused substantial reductions in natural forest area, biodiversity and carbon stocks. The EOS also requires substantial immigration of workers into a remote and ecologically important region with little social infrastructure for basic security, food security, health-care and education, causing frequently ignored costs. As expected, the COS will maintain the highest levels of natural forest area, sequester 57% more carbon, and 71% more biodiversity than EOS. Given the conservation value of the carbon stores and rich biodiversity residing in Xishuangbanna's natural forests, reducing rubber NPV only marginally would probably cost less than attempting to recover these resources. We recommend that rubber plantations be limited to established, productive lowland areas whilst protecting intact high-elevation forest and reforesting low-productivity plantations. These actions will enhance carbon sequestration and biodiversity conservation. Management policies focused solely on profits, like the EOS scenario, will fail to sustain the entire range of natural resources and ecosystem services. The prices in the carbon market would have to be considerably larger than they are currently to compete with the profitability of rubber. (C) 2014 Elsevier Ltd. All rights reserved
Protected areas:mixed success in conserving East Africa's evergreen forests
Get PDFIn East Africa, human population growth and demands for natural resources cause forest loss contributing to increased carbon emissions and reduced biodiversity. Protected Areas (PAs) are intended to conserve habitats and species. Variability in PA effectiveness and 'leakage' (here defined as displacement of deforestation) may lead to different trends in forest loss within, and adjacent to, existing PAs. Here, we quantify spatial variation in trends of evergreen forest coverage in East Africa between 2001 and 2009, and test for correlations with forest accessibility and environmental drivers. We investigate PA effectiveness at local, landscape and national scales, comparing rates of deforestation within park boundaries with those detected in park buffer zones and in unprotected land more generally. Background forest loss (BFL) was estimated at -9.3% (17,167 km(2)), but varied between countries (range: -0.9% to -85.7%; note: no BFL in South Sudan). We document high variability in PA effectiveness within and between PA categories. The most successful PAs were National Parks, although only 26 out of 48 parks increased or maintained their forest area (i.e. Effective parks). Forest Reserves (Ineffective parks, i.e. parks that lose forest from within boundaries: 204 out of 337), Nature Reserves (six out of 12) and Game Parks (24 out of 26) were more likely to lose forest cover. Forest loss in buffer zones around PAs exceeded background forest loss, in some areas indicating leakage driven by Effective National Parks. Human pressure, forest accessibility, protection status, distance to fires and long-term annual rainfall were highly significant drivers of forest loss in East Africa. Some of these factors can be addressed by adjusting park management. However, addressing close links between livelihoods, natural capital and poverty remains a fundamental challenge in East Africa's forest conservation efforts
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Market signals of unsustainable and inequitable forest extraction: assessing the value of illegal timber trade in the Eastern arc mountains of Tanzania
No full textNatural forests and woodlands of the Eastern Arc Mountains (EAM) in Tanzania are under threat from deforestation and degradation. The estimated annual revenues from EAM hardwood for domestic use are USD 10 million in terms of planks, and twice as much when processed into furniture. Timber profits are largely captured by people whose livelihoods do not directly depend on other EAM ecosystem services. Market data, such as declining plank sizes and shifts to low-quality timber species, contain possible early warning signals of unsustainable hardwood harvesting. Policy recommendations include simplifying regulations for legal trade, developingsustainable financing, and increasing softwood supply.Natural forests and woodlands of the Eastern Arc Mountains (EAM) in Tanzania are under threat from deforestation and degradation. The estimated annual revenues from EAM hardwood for domestic use are USD 10 million in terms of planks, and twice as much when processed into furniture. Timber profits are largely captured by people whose livelihoods do not directly depend on other EAM ecosystem services. Market data, such as declining plank sizes and shifts to low-quality timber species, contain possible early warning signals of unsustainable hardwood harvesting. Policy recommendations include simplifying regulations for legal trade, developingsustainable financing, and increasing softwood supply
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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