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1.
Plants (Basel) ; 12(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37896011

RESUMO

Patterns of species diversity have been associated with changes in climate across latitude and elevation. However, the ecological and evolutionary mechanisms underlying these relationships are still actively debated. Here, we present a complementary view of the well-known tropical niche conservatism (TNC) hypothesis, termed the multiple zones of origin (MZO) hypothesis, to explore mechanisms underlying latitudinal and elevational gradients of phylogenetic diversity in tree communities. The TNC hypothesis posits that most lineages originate in warmer, wetter, and less seasonal environments in the tropics and rarely colonize colder, drier, and more seasonal environments outside of the tropical lowlands, leading to higher phylogenetic diversity at lower latitudes and elevations. In contrast, the MZO hypothesis posits that lineages also originate in temperate environments and readily colonize similar environments in the tropical highlands, leading to lower phylogenetic diversity at lower latitudes and elevations. We tested these phylogenetic predictions using a combination of computer simulations and empirical analyses of tree communities in 245 forest plots located in six countries across the tropical and subtropical Andes. We estimated the phylogenetic diversity for each plot and regressed it against elevation and latitude. Our simulated and empirical results provide strong support for the MZO hypothesis. Phylogenetic diversity among co-occurring tree species increased with both latitude and elevation, suggesting an important influence on the historical dispersal of lineages with temperate origins into the tropical highlands. The mixing of different floras was likely favored by the formation of climatically suitable corridors for plant migration due to the Andean uplift. Accounting for the evolutionary history of plant communities helps to advance our knowledge of the drivers of tree community assembly along complex climatic gradients, and thus their likely responses to modern anthropogenic climate change.

2.
Front Plant Sci ; 14: 1135480, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909413

RESUMO

The science of tropical dendrochronology is now emerging in regions where tree-ring dating had previously not been considered possible. Here, we combine wood anatomical microsectioning techniques and radiocarbon analysis to produce the first tree-ring chronology with verified annual periodicity for a new dendrochronological species, Neltuma alba (commonly known as "algarrobo blanco") in the tropical Andes of Bolivia. First, we generated a preliminary chronology composed of six trees using traditional dendrochronological methods (i.e., cross-dating). We then measured the 14C content on nine selected tree rings from two samples and compared them with the Southern Hemisphere (SH) atmospheric 14C curves, covering the period of the bomb 14C peak. We find consistent offsets of 5 and 12 years, respectively, in the calendar dates initially assigned, indicating that several tree rings were missing in the sequence. In order to identify the tree-ring boundaries of the unidentified rings we investigated further by analyzing stem wood microsections to examine anatomical characteristics. These anatomical microsections revealed the presence of very narrow terminal parenchyma defining several tree-ring boundaries within the sapwood, which was not visible in sanded samples under a stereomicroscope. Such newly identified tree rings were consistent with the offsets shown by the radiocarbon analysis and allowed us to correct the calendar dates of the initial chronology. Additional radiocarbon measurements over a new batch of rings of the corrected dated samples resulted in a perfect match between the dendrochronological calendar years and the 14C dating, which is based on good agreement between the tree-ring 14C content and the SH 14C curves. Correlations with prior season precipitation and temperature reveal a strong legacy effect of climate conditions prior to the current Neltuma alba growing season. Overall, our study highlights much potential to complement traditional dendrochronology in tree species with challenging tree-ring boundaries with wood anatomical methods and 14C analyses. Taken together, these approaches confirm that Neltuma alba can be accurately dated and thereby used in climatic and ecological studies in tropical and subtropical South America.

3.
Sci Data ; 9(1): 511, 2022 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-35987763

RESUMO

We introduce the FunAndes database, a compilation of functional trait data for the Andean flora spanning six countries. FunAndes contains data on 24 traits across 2,694 taxa, for a total of 105,466 entries. The database features plant-morphological attributes including growth form, and leaf, stem, and wood traits measured at the species or individual level, together with geographic metadata (i.e., coordinates and elevation). FunAndes follows the field names, trait descriptions and units of measurement of the TRY database. It is currently available in open access in the FIGSHARE data repository, and will be part of TRY's next release. Open access trait data from Andean plants will contribute to ecological research in the region, the most species rich terrestrial biodiversity hotspot.


Assuntos
Biodiversidade , Plantas , Fenótipo , Folhas de Planta , Madeira
5.
PhytoKeys ; 186: 11-41, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34949955

RESUMO

The diversity of Cranichis in Bolivia is evaluated. An updated key for identifying species is provided. Morphological characteristics of 15 species of Bolivian Cranichis are presented together with illustrations of their floral segments. The occurrence of C.diphylla, C.lehmannii, and C.muscosa in this country was not confirmed. In our opinion the previously published Bolivian record for C.polyantha is doubtful. For the first time, C.badia and C.longipetiolata are reported in this country. Two new species of Cranichis are described.

6.
New Phytol ; 232(6): 2506-2519, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34379801

RESUMO

Recent studies have demonstrated that ecological processes that shape community structure and dynamics change along environmental gradients. However, much less is known about how the emergence of the gradients themselves shape the evolution of species that underlie community assembly. In this study, we address how the creation of novel environments leads to community assembly via two nonmutually exclusive processes: immigration and ecological sorting of pre-adapted clades (ISPC), and recent adaptive diversification (RAD). We study these processes in the context of the elevational gradient created by the uplift of the Central Andes. We develop a novel approach and method based on the decomposition of species turnover into within- and among-clade components, where clades correspond to lineages that originated before mountain uplift. Effects of ISPC and RAD can be inferred from how components of turnover change with elevation. We test our approach using data from over 500 Andean forest plots. We found that species turnover between communities at different elevations is dominated by the replacement of clades that originated before the uplift of the Central Andes. Our results suggest that immigration and sorting of clades pre-adapted to montane habitats is the primary mechanism shaping tree communities across elevations.


Assuntos
Biodiversidade , Ecossistema , Filogenia
8.
Nat Commun ; 12(1): 2138, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837222

RESUMO

It is largely unknown how South America's Andean forests affect the global carbon cycle, and thus regulate climate change. Here, we measure aboveground carbon dynamics over the past two decades in 119 monitoring plots spanning a range of >3000 m elevation across the subtropical and tropical Andes. Our results show that Andean forests act as strong sinks for aboveground carbon (0.67 ± 0.08 Mg C ha-1 y-1) and have a high potential to serve as future carbon refuges. Aboveground carbon dynamics of Andean forests are driven by abiotic and biotic factors, such as climate and size-dependent mortality of trees. The increasing aboveground carbon stocks offset the estimated C emissions due to deforestation between 2003 and 2014, resulting in a net total uptake of 0.027 Pg C y-1. Reducing deforestation will increase Andean aboveground carbon stocks, facilitate upward species migrations, and allow for recovery of biomass losses due to climate change.


Assuntos
Sequestro de Carbono/fisiologia , Carbono/metabolismo , Mudança Climática , Conservação dos Recursos Naturais , Árvores/metabolismo , Biomassa , Florestas , América do Sul , Clima Tropical
9.
Podium (Pinar Río) ; 15(3): 509-517, sept.-dic. 2020. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1143460

RESUMO

Resumen La introducción de las nuevas tecnologías en el béisbol ha optimizado los sistemas para el registro y análisis de información, tanto en el entrenamiento como en el juego, contribuyendo a un control más exacto del rendimiento de un jugador. En el presente trabajo, se aplica el sensor Blast Motion Baseball cuyo objetivo es identificar las variables significativamente influyentes en el rendimiento de los bateadores en el béisbol cubano. Se eligieron bateadores (N=24) pertenecientes a la Serie Nacional de béisbol LIX debido a que constituye el evento nacional de mayor nivel del béisbol cubano. La información fue registrada en prácticas de bateo, mientras el bateador ejecutaba la tarea de conectar bolas lanzadas por el entrenador de frente (front toss), por encima del brazo a una distancia de 30 pies y a una velocidad inferior a las 50 mph. Posteriormente, se compararon los resultados del Blast Motion Baseball con las estadísticas oficiales de la Serie Nacional de Béisbol LIX. Se demostró que los bateadores con mayor velocidad del bate, mayor velocidad máxima de las manos y mayor potencia lograron un mayor rendimiento ofensivo. Por tanto, conocer en tiempo real estas características del swing contribuyen a perfeccionar el proceso de entrenamiento y predecir el rendimiento deportivo de un bateador.


Resumo A introdução de novas tecnologias no basebol otimizou os sistemas de gravação e análise de informação, tanto no treino como no jogo, contribuindo para um controlo mais preciso do desempenho de um jogador. No presente trabalho, é aplicado o Sensor de basebol Blast Motion. O seu objetivo é identificar as variáveis que influenciam significativamente o desempenho dos batedores no basebol cubano. Os batedores (N=24) pertencentes à Série Nacional de basebol LIX foram escolhidos porque constitui o evento nacional de mais alto nível do basebol cubano. A informação foi registada durante o treino de batedores, enquanto o batedor executava a tarefa de ligar bolas lançadas pelo treinador a partir do lançamento frontal, sobre o braço a uma distância de 30 pés e a uma velocidade inferior a 50 mph. Os resultados do Blast Motion Baseball foram então comparados com as estatísticas oficiais da Série Nacional de Basebol LIX. Foi demonstrado que batedores com maiores velocidades de taco, maiores velocidades de mão superior, e mais potência alcançaram um maior desempenho ofensivo. Portanto, conhecer estas características do balanço em tempo real ajuda a refinar o processo de treino e a prever o desempenho atlético de um batedor.


Abstract The introduction of new technologies in baseball has optimized the systems for recording and analyzing information, both in training and in the game, contributing to a more accurate control of a player's performance. In this work, it is applied the Blast Motion Baseball sensor which objective is to identify the variables significantly influencing the performance of batters in Cuban baseball. There were chosen batters (N=24) belonging to the National Baseball Series LIX because it constitutes the national event of higher level in Cuban baseball. The information was recorded during batting practice, while the batter was performing the task of connecting balls thrown by the coach from the front toss, over the arm at a distance of 30 feet and at a speed of less than 50 mph. The results of Blast Motion Baseball were then compared with the official statistics of the LIX National Baseball Series. It was shown that batters with higher bat speed, higher top hand speed and more power achieved greater offensive performance. Therefore, knowing these characteristics of the swing in real time helps to perfect the training process and predict the sports performance of a batter.

10.
PLoS One ; 15(4): e0231553, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32311701

RESUMO

Our knowledge about the structure and function of Andean forests at regional scales remains limited. Current initiatives to study forests over continental or global scales still have important geographical gaps, particularly in regions such as the tropical and subtropical Andes. In this study, we assessed patterns of structure and tree species diversity along ~ 4000 km of latitude and ~ 4000 m of elevation range in Andean forests. We used the Andean Forest Network (Red de Bosques Andinos, https://redbosques.condesan.org/) database which, at present, includes 491 forest plots (totaling 156.3 ha, ranging from 0.01 to 6 ha) representing a total of 86,964 identified tree stems ≥ 10 cm diameter at breast height belonging to 2341 identified species, 584 genera and 133 botanical families. Tree stem density and basal area increases with elevation while species richness decreases. Stem density and species richness both decrease with latitude. Subtropical forests have distinct tree species composition compared to those in the tropical region. In addition, floristic similarity of subtropical plots is between 13 to 16% while similarity between tropical forest plots is between 3% to 9%. Overall, plots ~ 0.5-ha or larger may be preferred for describing patterns at regional scales in order to avoid plot size effects. We highlight the need to promote collaboration and capacity building among researchers in the Andean region (i.e., South-South cooperation) in order to generate and synthesize information at regional scale.


Assuntos
Altitude , Biodiversidade , Florestas , Árvores , Clima , América do Sul
11.
PLoS One ; 10(3): e0121458, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25803846

RESUMO

Despite long-standing interest in elevational-diversity gradients, little is known about the processes that cause changes in the compositional variation of communities (ß-diversity) across elevations. Recent studies have suggested that ß-diversity gradients are driven by variation in species pools, rather than by variation in the strength of local community assembly mechanisms such as dispersal limitation, environmental filtering, or local biotic interactions. However, tests of this hypothesis have been limited to very small spatial scales that limit inferences about how the relative importance of assembly mechanisms may change across spatial scales. Here, we test the hypothesis that scale-dependent community assembly mechanisms shape biogeographic ß-diversity gradients using one of the most well-characterized elevational gradients of tropical plant diversity. Using an extensive dataset on woody plant distributions along a 4,000-m elevational gradient in the Bolivian Andes, we compared observed patterns of ß-diversity to null-model expectations. ß-deviations (standardized differences from null values) were used to measure the relative effects of local community assembly mechanisms after removing sampling effects caused by variation in species pools. To test for scale-dependency, we compared elevational gradients at two contrasting spatial scales that differed in the size of local assemblages and regions by at least an order of magnitude. Elevational gradients in ß-diversity persisted after accounting for regional variation in species pools. Moreover, the elevational gradient in ß-deviations changed with spatial scale. At small scales, local assembly mechanisms were detectable, but variation in species pools accounted for most of the elevational gradient in ß-diversity. At large spatial scales, in contrast, local assembly mechanisms were a dominant force driving changes in ß-diversity. In contrast to the hypothesis that variation in species pools alone drives ß-diversity gradients, we show that local community assembly mechanisms contribute strongly to systematic changes in ß-diversity across elevations. We conclude that scale-dependent variation in community assembly mechanisms underlies these iconic gradients in global biodiversity.


Assuntos
Altitude , Biodiversidade , Biota , Modelos Biológicos , Fenômenos Fisiológicos Vegetais , Bolívia , Análise dos Mínimos Quadrados , Análise de Regressão , Análise Espacial , Especificidade da Espécie , Clima Tropical
12.
Montevideo; s.n; 1925. 13 p.
Não convencional em Espanhol | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1235792

Assuntos
Hanseníase
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