| 1. |
- Householder, John Ethan, et al.
(författare)
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One sixth of Amazonian tree diversity is dependent on river floodplains
- 2024
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Ingår i: NATURE ECOLOGY & EVOLUTION. - 2397-334X.
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Tidskriftsartikel (refereegranskat)abstract
- Amazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region's floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon's tree diversity and its function.
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| 2. |
- Luize, Bruno Garcia, et al.
(författare)
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Geography and ecology shape the phylogenetic composition of Amazonian tree communities
- 2024
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Ingår i: JOURNAL OF BIOGEOGRAPHY. - 0305-0270 .- 1365-2699.
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and v & aacute;rzea forest types, the phylogenetic composition varies by geographic region, but the igap & oacute; and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R-2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R-2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions.
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| 3. |
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| 4. |
- Mateu, Pau, et al.
(författare)
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Living Life Through Sport : The Transition of Elite Spanish Student-Athletes to a University Degree in Physical Activity and Sports Sciences
- 2020
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Ingår i: Frontiers in Psychology. - Lausanne : Frontiers Research Foundation. - 1664-1078. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Interest in studying the different transitions faced by elite athletes throughout their careers has grown significantly in recent years. While transition from secondary school to university is an important research area in Europe, there is a void of studies on how student-athletes experience the transition to specific degrees. One of the most sought-after university degrees among elite athletes in Spain is a degree in Physical Activity and Sport Sciences (PASS). The first aim of this study was to investigate the main demands, barriers, and resources perceived by elite student-athletes in various phases of dual career transition to a university degree in PASS. The second aim was to identify the transition pathways pursued depending on the subjective importance they attached to sport and education. Eleven elite student-athletes (Mage = 20.7, SD = 1.6 years) who were in their second and third year of the degree in PASS participated in semi-structured interviews. Deductive-inductive thematic analysis of the interview transcripts revealed three main themes: (a) general university transition issues, (b) PASS-specific transition issues, and (c) transition pathways. Our results show that the close link between sport and the content of the degree was perceived by the elite student-athletes as their main resource. This link, however, was also perceived as a major barrier as the compulsory practical subjects entailed a risk of injury or overtraining that could affect both athletic and academic development. We noticed how the importance they attached to sport or studies varied at different moments of the transition period, a phenomenon we termed “fluid transition pathways.†Dual career promotion for elite athletes is an important part of European sports policy, and our findings provide new knowledge that could help Spanish PASS faculties develop specific assistance programs to support transitioning student-athletes. © 2020 © 2020 Mateu, Inglés, Torregrossa, Marques, Stambulova and Vilanova.
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| 5. |
- Nunomura, Myrian, et al.
(författare)
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Coming of Age in Women Artistic Gymnastics: The influence of rules on career development
- 2015
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Ingår i: 12th European Association for Sociology of Sport Conference, 10-13 Juni, 2015, Dublin, Ireland.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Age has long been debated in women’s artistic gymnastics (WAG). Since the 1970s, young gymnasts with pre-pubescent physiques and extreme levels of performance tend to dominate the sport. Growing critique of the problematic side-effects of this trend led the International Gymnastics Federation (FIG) to introduce the minimum age limit of 16 for international competitions in 1996. Since then, the FIG has implemented further changes through their rules book the Code of Points, which have implications for gymnasts’ career development. In drawing on results from an interview study with more than 20 internationally successful gymnasts who are/were over the age of 20 when competing, as well as coaches and judges, this presentation discusses the impact of the Code of Points on career development. The findings demonstrate that on the one hand, stakeholders spoke of how the Code of Points related to gymnasts extending their career into their twenties. In particular, the changes towards artistry are important criteria that interviewees related to career continuation. On the other hand, the increased difficulty requirements since the beginning of 2000 continue to place enormous pressures on gymnasts to train intensely from a young age. The physical demands and the risk for injuries detriment gymnasts’ career prolongation. We conclude that although the FIG has made some efforts to encourage the presence of older gymnasts, these have only been semi-successful, with a younger, pre-pubescent body still viewed as ideal for WAG.
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| 6. |
- Rodrigues Marques, Renato Francisco, et al.
(författare)
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From soccer to futsal: Brazilian elite-level men players’ career pathways
- 2021
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Ingår i: Soccer & Society. - : Informa UK Limited. - 1466-0970 .- 1743-9590. ; 22:5, s. 486-501
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Tidskriftsartikel (refereegranskat)abstract
- Many Brazilian boys dream of a professional soccer career. During adolescence, however, many players move into futsal, a popular, less professionalized counterpart to soccer. To study players’ investment in a futsal career, this article aimed to understand how childhood socialization relates to players’ career development; to reconstruct the pathways players developed to become elite futsal athletes; and to identify reasons that led players to move from soccer to futsal. Semi-structured interviews with 18 Brazilian national team futsal players provided data. Bourdieu’s Theory of Social Fields helped to understand players’ investment in futsal. The results show that players experienced a fruitful social context and familial socialization that facilitated ‘ball-kicking capitals’; developed a habitus that better matched the futsal than the soccer subfield; and delegitimized soccer as a suitable environment to participate in. We conclude with critical implications for futsal and soccer stakeholders aiming to maintain/create attractive career environments in times of increasing professionalism
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| 7. |
- Rodrigues Marques, Renato Francisco, et al.
(författare)
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Moving Away: Intra-National Migration Experiences of Brazilian Men Elite Futsal Players During Youth
- 2022
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Ingår i: International Review for the Sociology of Sport. - : SAGE Publications. - 1012-6902 .- 1461-7218. ; 57:6
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Tidskriftsartikel (refereegranskat)abstract
- Migration experiences are common for athletes, especially in team sports. Moving from home to a recruiting sport club has become an indispensable career investment. This is also the case in Brazilian futsal, where many developing players move to more promising clubs within the country. This process is often challenging, but little researched. The purpose of this article is to investigate 13 Brazilian men elite futsal players’ intra-national migration experiences during their youth. We aim to: provide insight into what factors allowed players to invest in a futsal career through migration; demonstrate the challenges young players faced during their migration; and describe how they adapted to the futsal context they had moved to. We use a Bourdieusian framework to examine young futsal players’ disposition to intra-national migration and the influence of capitals on their integration in the receiving places. A thematic analysis allowed us to identify that: Players’ disposition to migration was shaped by their families’ habitus and illusio related to futsal; some of the reported issues could have been avoided if clubs had provided more efficient support to young migrant athletes; and families and networks (social capital) were key for players being able to adapt to the new futsal context.
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| 8. |
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| 9. |
- Sarneel, Judith M., et al.
(författare)
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Reading tea leaves worldwide : decoupled drivers of initial litter decomposition mass-loss rate and stabilization
- 2024
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Ingår i: Ecology Letters. - : John Wiley & Sons. - 1461-023X .- 1461-0248. ; 27:5
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Tidskriftsartikel (refereegranskat)abstract
- The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.
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| 10. |
- ter Steege, Hans, et al.
(författare)
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Mapping density, diversity and species-richness of the Amazon tree flora
- 2023
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Ingår i: COMMUNICATIONS BIOLOGY. - 2399-3642. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution. A study mapping the tree species richness in Amazonian forests shows that soil type exerts a strong effect on species richness, probably caused by the areas of these forest types. Cumulative water deficit, tree density and temperature seasonality affect species richness at a regional scale.
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