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1.
Glob Chang Biol ; 30(1): e17140, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38273497

ABSTRACT

Growing evidence suggests that liana competition with trees is threatening the global carbon sink by slowing the recovery of forests following disturbance. A recent theory based on local and regional evidence further proposes that the competitive success of lianas over trees is driven by interactions between forest disturbance and climate. We present the first global assessment of liana-tree relative performance in response to forest disturbance and climate drivers. Using an unprecedented dataset, we analysed 651 vegetation samples representing 26,538 lianas and 82,802 trees from 556 unique locations worldwide, derived from 83 publications. Results show that lianas perform better relative to trees (increasing liana-to-tree ratio) when forests are disturbed, under warmer temperatures and lower precipitation and towards the tropical lowlands. We also found that lianas can be a critical factor hindering forest recovery in disturbed forests experiencing liana-favourable climates, as chronosequence data show that high competitive success of lianas over trees can persist for decades following disturbances, especially when the annual mean temperature exceeds 27.8°C, precipitation is less than 1614 mm and climatic water deficit is more than 829 mm. These findings reveal that degraded tropical forests with environmental conditions favouring lianas are disproportionately more vulnerable to liana dominance and thus can potentially stall succession, with important implications for the global carbon sink, and hence should be the highest priority to consider for restoration management.


Des preuves de plus en plus nombreuses suggèrent que la competition entre lianes et les arbres menace le puits de carbone mondial en ralentissant la récupération des forêts après une perturbation. Une théorie récente, fondée sur des observations locales et régionales, propose en outre que le succès compétitif des lianes sur les arbres est dû aux interactions entre la perturbation forestière et le climat. Nous présentons la première évaluation mondiale de la performance relative des lianes par rapport aux arbres en réponse aux perturbations forestières et aux facteurs climatiques. En utilisant un ensemble de données sans précédent, nous avons analysé 651 échantillons de végétation représentant 26,538 lianes et 82,802 arbres, issus de 556 emplacements uniques dans le monde entier, tirés de 83 publications. Les résultats montrent que les lianes ont de meilleure performances par rapport aux arbres (augmentation du ratio liane-arbre) lorsque les forêts sont perturbées, sous des zones chaudes aves précipitations faibles, et vers les basses altitudes tropicales. Nous avons également constaté que les lianes peuvent être un facteur critique entravant la récupération des forêts dans les forêts perturbées connaissant des climats favorables aux lianes, car les données de chronoséquence montrent que le succès compétitif élevé des lianes sur les arbres peut persister pendant des décennies après les perturbations, surtout lorsque la température annuelle moyenne dépasse 27.8°C, que les précipitations sont inférieures à 1614 mm et que le déficit hydrique climatique est supérieur à 829 mm. Ces découvertes révèlent que les forêts tropicales dégradées avec des conditions environnementales favorables aux lianes sont disproportionnellement plus vulnérables à la dominance des lianes, et peuvent ainsi potentiellement entraver la succession, avec d'importantes implications pour le puits de carbone mondial et devraient donc être la plus haute priorité à considérer pour la gestion de la restauration.


Subject(s)
Trees , Tropical Climate , Trees/physiology , Forests , Carbon Sequestration , Water
2.
Photochem Photobiol Sci ; 22(12): 2817-2826, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37847459

ABSTRACT

BACKGROUND: Overexposure to sunlight and sunburn are the main preventable causes of skin cancer. Outdoor sports are associated with significant levels of sunlight exposure. AIMS: We sought to quantify the sun radiation exposure received by outdoor rock climbers and assess their sun exposure habits, sun protection behaviors, attitudes, and knowledge regarding skin cancer. METHODS: From April to June 2021, outdoor rock climbers contacted via email completed an online validated self-reported questionnaire on sun related habits, behaviors, attitudes and knowledge. As a pilot trial, ten participants wore a personal dosimeter during two outdoor climbing weekends in May and November 2021. Ambient ultraviolet radiation (UVR) was also recorded. RESULTS: A total of 217 outdoor rock climbers (103 women), mean age 36.8 ± 8.8 years (range 20-70 years) and median climbing practice per week of 8 h (IQR 7.5) were studied. Two in three (65.9%) participants reported at least one sunburn event during the previous rock climbing season. Of the survey respondents, 49.3% reported using sunscreen with SPF ≥ 15, 47% wore sunglasses, and 14.3% indicated they reapplied sunscreen every two hours. The median personal UVR dose measured during the two outdoor climbing weekends analyzed was 5.2 (IQR 1.8) and 8.8 (IQR 1.1) standard erythemal doses, respectively. CONCLUSIONS: The high rates of sunburn, the elevated personal UVR measured and the clearly insufficient sun protection practices followed during rock climbing together with unsatisfactory attitudes towards tanning reveal the need to develop explicit sun protection campaigns and educational strategies to reduce the risk of skin cancer among the athletes studied.


Subject(s)
Skin Neoplasms , Sunburn , Female , Humans , Skin Neoplasms/etiology , Skin Neoplasms/prevention & control , Skin Neoplasms/drug therapy , Sunburn/etiology , Sunburn/prevention & control , Sunlight/adverse effects , Sunscreening Agents/therapeutic use , Ultraviolet Rays/adverse effects , Young Adult , Adult , Middle Aged , Aged , Male
3.
Bot Stud ; 64(1): 26, 2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37736799

ABSTRACT

BACKGROUND: The climbing strategies of lianas and herbaceous vines influence climber competition abilities and survival. The aim of this study was to investigate the climbing strategies of each plant species and observe their organs of origin. RESULTS: The results showed that all Taiwan climbers were approximately 555 species, accounting for 11% of the native flora. Among the 555 climbers, the twining stem type was the most common, with a total of 255 species (46%), the remaining climbing methods accounted for 300 species. Approximately twenty one climbing methods, including nine combination types, were exhibited, of which the most common type was the twining stem, followed by simple scrambling and twining tendrils. Most species of Fabaceae and Apocynaceae were twining stems in dextrorse, excluding Wisteriopsis reticulata and Alyxia taiwanensis, which were in sinistrorse. The prehensile branch of Fissistigma genus, Ventilago genus, and Dalbergia benthamii, originated from second-order or modified stems. In the simple scrambling type, some climbers were covered spines and prickles to attach the host, and the others were clinging to the supports or creeping on the ground without speculation. The hooks or grapnels of the genus Uncaria are derived from the branches, and a pair of curved hooks or a spine of Artabotrys hexapetalus are originated from the inflorescence to tightly attach to a host. The Piper genus use adhesive roots to climb their hosts. Among the genus Trichosanthes, only Trichosanthes homophylla exhibits a combination of twining modified shoots and adhesive roots. Gentianales includes four families with seven climbing mechanisms, while Fabales includes only Fabaceae, which presents six climbing methods. CONCLUSIONS: The twining tendrils had nine organs of origin in Taiwan climber, that these opinions of originated organs might be available to the studies of convergent evolution. The data presented herein provide crucial basic information of the climber habits types and origin structures, which are available for terms standardization to improve field investigation. The terminologies would aid in the establishment of climber habits as commonly taxon-specific and the combination of two climber habits could be a characteristic of taxonomic value.

4.
Eur J Sport Sci ; 23(10): 2031-2037, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37167343

ABSTRACT

Grip and elbow flexor strength and endurance are crucial performance surrogates in competitive climbing. Thus, we examined the effects of blood flow restricted (BFR) climbing on grip and elbow flexor performance. Fifteen trained climbers (8 females; 20.8 ± 7.0 yrs; 1.72 ± 0.08 m; 63.0 ± 9.7 kg; 21.7 ± 2.7 IRCRCA grade) were either assigned to the intervention (BFR) or control (noBFR) group, using the minimization method (Strata: age, height, body mass, gender, and IRCRA grade). While BFR was used during low-intensity climbing training (2-times 10 min/session; 3-times/week), noBFR followed identical training protocols without BFR over 5 weeks. BFR of the upper limb was applied via customized pneumatic cuffs (occlusion pressure: 120 ± 23 mmHg, 75%; occlusion pressure). Endurance and strength performances were assessed via one-handed rung pulling (GripSTRENGTH), one-handed bent arm lock off at 90° (ArmSTRENGTH), static-intermitted finger hang (GripENDURANCE), and bent arm hang (ArmENDURANCE). Bayesian credible intervals revealed increased GripENDURANCE (+21 s (95% credible interval: -2 to 43 s)) and ArmENDURANCE +11 s (-5 to 27 s); adaptations via BFR. In contrast, GripSTRENGTH +4 N (-40 to 48 N) and ArmSTRENGTH +4 N (-68 to 75 N) were not affected by the BFR intervention. Fifteen cumulative sessions of BFR application with a cumulative total BFR load of 5 h over a 5 weeks macrocycle remarkably increased grip and elbow flexor endurance. Thus, BFR might serve as a promising means to improve relevant performance surrogates in trained climbers.


Blood flow restricted (BFR) climbing induced superior grip and elbow flexor endurance adaptations compared to non-restricted climbing training over a 5-week lasting training periodBFR and non-BFR climbing training induced similar grip and elbow flexor strength adaptationsTherefore, BFR served as a feasible, promising and beneficial complementary training stimuli additionally to the sheduled climbing training program.


Subject(s)
Elbow , Resistance Training , Female , Humans , Bayes Theorem , Muscle, Skeletal/physiology , Hand Strength/physiology , Upper Extremity , Regional Blood Flow/physiology
5.
Preprint in Portuguese | SciELO Preprints | ID: pps-5619

ABSTRACT

A taxonomic study of the representatives of the Apocynoid grade (Apocynaceae) in Eastern Northeast Brazil is presented, and includes an identification key, morphological descriptions, comments, illustrations, photos, and a table. The study area includes the States of Ceará, Rio Grande do Norte, Paraíba, Pernambuco and Alagoas. The botanical material was collected, prepared, and deposited at the UFP herbarium. The collections of regional herbaria were analyzed. A total of 28 species were recorded belonging to seven genera, being Mandevilla (nine spp.), Prestonia (six spp.), Forsteronia (five spp.), Macropharynx, Odontadenia, Secondatia e Temnadenia (two spp. each). The State with the highest number of species was Pernambuco (21 spp.) and the most species-rich phytogeographic domain was the Atlantic Forest (21 spp.). Most species are climbers and vines (27 spp.), except Mandevilla dardanoi (subshrub) and M. tenuifolia (climber or erect subshrub). Ten species had their distribution expanded in the study area. The follicles of Mandevilla catimbauensis are illustrated by the first time.


Um estudo taxonômico do grado Apocynoid (Apocynaceae) no Nordeste Oriental do Brasil é apresentado, e inclui uma chave de identificação, descrições morfológicas, comentários, ilustrações, fotos e uma tabela. A área de estudo inclui os Estados do Ceará, Rio Grande do Norte, Paraíba, Pernambuco e Alagoas. O material botânico foi coletado, preparado e depositado no herbário UFP. As coleções de herbários regionais foram analisadas. Um total de 28 espécies foi registro pertencente a sete gêneros: Mandevilla (nove spp.), Prestonia (seis spp.), Forsteronia (cinco spp.), Macropharynx, Odontadenia, Secondatia e Temnadenia (duas spp. cada). O Estado com maior número de espécies foi Pernambuco (21 spp.) e o domínio fitogeográfico mais rico foi a Mata Atlântica (21 spp.). A maioria das espécies é composta por trepadeiras e lianas (27 spp.), exceto Mandevilla dardanoi (subarbusto) e M. tenuifolia (trepadeira ou subarbusto ereto). Dez espécies tiveram sua distribuição ampliada na área de estudo. Os folículos de Mandevilla catimbauensis são ilustrados pela primeira vez.

6.
Biol Sport ; 40(1): 179-191, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36636194

ABSTRACT

The objective of this systematic review and meta-analysis was to examine the effects of climbing and climbing-and-resistance-training on climbing performance, and strength and endurance tests. We systematically searched three databases (SPORTDiscus, SCOPUS, and PubMed) for records published until January 2021. The search was limited to randomized-controlled trials using active climbers and measuring climbing performance or performance in climbing-specific tests. Data from the meta-analysis are presented as standardized difference in mean (SDM) with 95% confidence intervals (95% CI). Eleven studies are included in the systematic review and five studies compared training to a control group and could be meta-analyzed. The overall meta-analysis displayed an improvement in climbing-related test performance following climbing-specific resistance training compared to only climbing (SDM = 0.57, 95%CI = 0.24-0.91). Further analyses revealed that finger strength (SDM = 0.41, 95%CI 0.03-0.80), rate of force development (SDM = 0.91, 95%CI = 0.21-1.61), and forearm endurance (SDM = 1.23, 95%CI = 0.69-1.77) were improved by resistance-training of the finger flexors compared to climbing training. The systematic review showed that climbing performance may be improved by specific resistance-training or interval-style bouldering. However, resistance-training of the finger flexors showed no improvements in strength or endurance in climbing-specific tests. The available evidence suggests that resistance-training may be more effective than just climbing-training for improving performance outcomes. Importantly, interventional studies including climbers is limited and more research is needed to confirm these findings.

7.
Front Psychol ; 13: 1012792, 2022.
Article in English | MEDLINE | ID: mdl-36533041

ABSTRACT

Introduction: The ascent of a route can be defined as being climbed on-sight or red-point. Climbing performance is measured by the grade of the personal best route that the athlete has ever climbed. Methodology: The study examined 17 youth climbers (10 male and 7 female). The inclusion criteria were age (less than 20 years), a minimum of three sessions per week, a minimum 7a climbing grade and participation in national or international competitions. We used the Cognitrom battery and applied tests measuring spatial orientation and reactivity. Results: Climbing experience explained 42.7% of the variance of on-sight performance, and 49.5% of the variance of red-point performance. Image generation has a negative on both on-sight and red-point performance, lowering the prediction with 0.5% for on-sight climbing and with 1.5% for red-point climbing. Discussion: Experience can predict climbing performance with a better prediction for red-point performance than on-sight with almost 7%. A high level of image generation ability can lead to viewing more approaches for passing the crux, but in a moment of physical and mental breakdown, can lead to failure. Red-pointing is less demanding than on-sight from physiological and psychologycal points of view. On-sight climbing requires greater levels of cognitive skills, such as route intepretation strategies, spatial orientation, motric memory, problem-solving skills, but also greater levels of psychological skills such as stress management, risk management, coping anxiety.

9.
Int J Exerc Sci ; 15(4): 834-845, 2022.
Article in English | MEDLINE | ID: mdl-35992502

ABSTRACT

Indoor sport rock climbing has been increasing in popularity both recreationally and competitively. Despite this increase in popularity, the physiological responses to sport climbing as an exercise to specific muscle groups are not well defined. The purpose of this study was to quantify the change in handgrip strength over a 30-minute bout of continuous climbing, specifically in intermediate-level sport climbers. Ten intermediate rock climbers (age = 27 ± 2 years; climbing experience: 7.3 ± 1.5 years) completed baseline handgrip strength and forearm girth measurements. Each participant ascended one of two 5.9 difficulty routes as many times as possible in 30 minutes. After each ascent, heart rate was obtained, and handgrip strength and forearm girth were measured. Data were analyzed using repeated-measures ANOVA with significance set at α < 0.05. Dominant arm handgrip strength decreased by 22%, and non-dominant handgrip strength reduced by 23%. Dominant and non-dominant forearm girth increased by 4.5% and 4.4%, respectively. Weak but significant negative correlations were observed between handgrip strength and forearm girth in dominant (r = -0.311, p = 0.001) and non-dominant limbs (r = -.491, p = 0.001). These results indicate a relationship between increased forearm girth and decreases in muscular strength. Since handgrip strength decreases substantially during a 30-min climb in intermediate rock climbers, this population would be advised to carefully monitor recovery time between bouts.

11.
J Hand Surg Am ; 47(7): 662-672, 2022 07.
Article in English | MEDLINE | ID: mdl-35256226

ABSTRACT

Rock climbing places substantial stress on the upper extremities and can lead to unique injuries not common to other sports. With increasing popularity of the sport, hand surgeons are expected to see more patients with these pathologies. An understanding of the sport, accurate diagnoses, and appropriate treatment protocols are critical to maintain climbers' competitive abilities.


Subject(s)
Arm Injuries , Athletic Injuries , Mountaineering , Sports , Arm Injuries/diagnosis , Arm Injuries/therapy , Athletic Injuries/diagnosis , Athletic Injuries/therapy , Humans , Mountaineering/injuries , Upper Extremity/injuries
12.
Int J Sports Physiol Perform ; 17(5): 768-773, 2022 05 01.
Article in English | MEDLINE | ID: mdl-35235904

ABSTRACT

PURPOSE: To determine the relative contributions of handgrip and individual finger strength for the prediction of climbing performance in a bouldering competition. A secondary aim was to examine the influence of body size, bouldering experience, and training habits. METHODS: Sixty-seven boulderers (mean [SD], age = 21.1 [4.0] y; body mass = 69.5 [9.8] kg) volunteered for this study. Data collection occurred immediately before an indoor bouldering competition and involved the assessment of handgrip and individual finger maximal force production using an electronic handheld dynamometer. The bouldering competition consisted of 70 routes graded V0 to V8, with higher point values awarded for completing more difficult routes. Stepwise multiple regression analysis was used to examine the relative contributions of handgrip and individual finger strengths, body mass, height, bouldering experience, and bouldering frequency to the prediction of performance scores in the competition. RESULTS: Ring finger pinch strength, bouldering experience, and bouldering frequency significantly (P < .05) contributed to the model (R2 = .373), whereas body mass; height; full handgrip strength, as well as index, middle, and little finger pinch strengths did not. The ß weights showed that ring finger pinch strength (ß = .430) was the most significant contributor, followed by bouldering experience (ß = .331) and bouldering frequency (ß = .244). CONCLUSIONS: The current findings indicated that trainable factors contributed to the prediction of bouldering performance. These results suggest greater bouldering frequency and experience likely contribute to greater isolated individual finger strength, thereby optimizing preparation for the diverse handholds in competitive rock climbing.


Subject(s)
Hand Strength , Mountaineering , Adult , Body Height , Fingers , Humans , Young Adult
13.
J Travel Med ; 29(5)2022 08 20.
Article in English | MEDLINE | ID: mdl-35348739

ABSTRACT

BACKGROUND: Each year several Mt. Kilimanjaro hikers die due to altitude illness (AI) although urgent descent is technically easily possible. The objectives of this study were to determine the incidence and predictors of severe altitude illness (SAI) symptoms and of summit success in Mt. Kilimanjaro hikers, and the measures taken when AI symptoms develop. METHODS: A prospective observational cohort study in Mt. Kilimanjaro hikers was conducted from December 2019 until March 2020. Participants were asked to complete a questionnaire at the entrance gate and one at the descend gate. A multivariate logistic regression was performed to study the relations between the variables. RESULTS: A total of 1237 recreational hikers and 266 porters or guides were included. The incidence of severe symptoms was 8.6% in recreational hikers and 1.5% in porters and guides. One percent (1.1%) of hikers was hospitalized due to SAI. A history of SAI, young age, summit failure and lack of clear advice predicted the development of severe symptoms. Uhuru peak was reached by 87.9% of the hikers. Absence of severe symptoms, acetazolamide prophylaxis, climbing higher in daytime, young age and climbing in more days predicted summit success. The majority climbed further despite the presence of mild or severe symptoms. The only measure taken in case of mild symptoms that was associated with a lower incidence of severe symptoms was not climbing further. CONCLUSION: The incidence of SAI symptoms in Mt. Kilimanjaro hikers was observed to be high. However, how hikers reacted during symptoms was not appropriate. Therefore, travel health counsellors should emphasize even more that hikers do not ascend higher until mild symptoms have resolved and that it is vital to descend immediately when severe symptoms develop. In addition, they can be informed on the measures, which improved summit success.


Subject(s)
Altitude Sickness , Mountaineering , Acute Disease , Altitude , Altitude Sickness/epidemiology , Altitude Sickness/prevention & control , Humans , Incidence , Prospective Studies , Tanzania/epidemiology
14.
Orthop J Sports Med ; 10(2): 23259671211073137, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35174249

ABSTRACT

BACKGROUND: The prevalence of findings on shoulder magnetic resonance imaging (MRI) is high in asymptomatic athletes of overhead sports. PURPOSE/HYPOTHESIS: The purpose of this study was to determine the prevalence of atypical findings on MRI in shoulders of asymptomatic, elite-level climbers and to evaluate the association of these findings with clinical examination results. It was hypothesized that glenoid labrum, long head of the biceps tendon, and articular cartilage pathology would be present in >50% of asymptomatic athletes. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 50 elite climbers (age range, 20-60 years) without any symptoms of shoulder pain underwent bilateral shoulder examinations in addition to dedicated bilateral shoulder 3-T† MRI. Physical examinations were performed by orthopaedic sports medicine surgeons, while MRI scans were interpreted by 2 blinded board-certified radiologists to determine the prevalence of abnormalities of the articular cartilage, glenoid labrum, biceps tendon, rotator cuff, and acromioclavicular joint. RESULTS: MRI evidence of tendinosis of the rotator cuff, subacromial bursitis, and long head of the biceps tendonitis was exceptionally common, at 80%, 79%, and 73%, respectively. Labral pathology was present in 69% of shoulders, with discrete labral tears identified in 56%. Articular cartilage changes were also common, with humeral pathology present in 57% of shoulders and glenoid pathology in 19% of shoulders. Climbers with labral tears identified in this study had significantly increased forward elevation compared with those without labral tears in both active (P = .026) and passive (P = .022) motion. CONCLUSION: The overall prevalence of intra-articular shoulder pathology detected by MRI in asymptomatic climbers was 80%, with 57% demonstrating varying degrees of glenohumeral articular cartilage damage. This high rate of arthritis differs significantly from prior published reports of other overhead sports athletes.

15.
J Clin Med ; 10(21)2021 Oct 28.
Article in English | MEDLINE | ID: mdl-34768532

ABSTRACT

BACKGROUND: The aim of this study was to assess the effects that psychological and physiological stressors have on indoor rock climbers, as well as to identify sex differences. METHODS: 14 intermediate rock climbers participated in the study, 10 males and 4 females. Mean age was 31 ± 8 years for males and 21 ± 2 years for females. Day 1 consisted of test familiarization and baseline measurements. Day 2 included two test conditions, startle and fatigue, separated by 20 min. In the startle condition, participants had to lead climb a route, and a loud audio stimulus was presented near the top of the climb. In the fatigue condition, participants were required to climb as fast as they could until muscular failure. The competitive state anxiety inventory second review (CSAI-2R) questionnaire was used to assess somatic anxiety, cognitive anxiety, and self-confidence. The four-square step test (FSST) was used to assess motor control, and cortisol levels were acquired via passive drool (PD). RESULTS: Cortisol concentrations were highest in the pre-startle condition (1.72 µg/dL ± 0.66), and values decreased post-startle (1.67 µg/dL ± 0.74) and post-fatigue (1.42 µg/dL ± 0.72). However, cortisol concentrations increased post-startle in females (1.57 µg/dL ± 0.96). Somatic anxiety in males was significantly higher post-startle (16.36 ± 5.54) than pre-startle (14.23 ± 5.09). Females had significantly higher somatic anxiety post-startle (18.00 ± 8.76), and they had lower self-confidence levels (30.00 ± 5.89) than males. CONCLUSIONS: There are differences in the way that males and females prepare and respond to stressful situations. Furthermore, time of day may have had a significant impact on cortisol concentrations.

16.
Ecology ; 102(12): e03541, 2021 12.
Article in English | MEDLINE | ID: mdl-34582567

ABSTRACT

Lightning is a common source of disturbance, but its ecological effects in tropical forests are largely undescribed. Here we quantify the contributions of lightning strikes to forest turnover and plant mortality in a lowland Panamanian forest using a real-time lightning monitoring system. We examined 2,195 lightning-damaged trees distributed among 93 different strikes. None exhibited scars or fires. On average, each strike disturbed 451 m2 (95% CI: 365-545 m2 ), created a canopy gap of 304 m2 (95% CI 198-454 m2 ), and caused 7.36 Mg of woody biomass turnover (CI: 5.36-9.65 Mg). Cumulatively, we estimate that lightning strikes in this forest create canopy gaps equaling 0.39% of forest canopy area, representing 20.1% of annual gap area formation, and are responsible for 16.1% of total woody biomass turnover. Trees, lianas, herbaceous climbers and epiphytes were killed by lightning at rates 8-29 times greater than their baseline mortality rates in undamaged control sites. The likelihood of lightning-caused death was higher for trees, lianas, and herbaceous climbers than for epiphytes, and high liana mortality suggests that lightning is an important driver of liana turnover. These results indicate that lightning influences gap dynamics, plant community composition and carbon storage capacity in some tropical forests.


Subject(s)
Lightning , Tropical Climate , Biomass , Forests , Plants , Trees
17.
Biol Sport ; 38(2): 229-234, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34079167

ABSTRACT

Sport climbing will become an official event at the 2020 Tokyo Olympics; it is a popular wilderness sport among athletes and amateurs. Our previous study suggested that the T1470A polymorphism (rs1049434) of the monocarboxylate transporter 1 (MCT1) gene is associated with athletic performance and physiological phenotypes. The purpose of this study was to investigate the frequency of MCT1 T1470A polymorphism in Polish and Japanese climbers using a case-control study. Our sample consisted of 226 climbers (Japanese: n = 100, 64 male and 36 female; Polish: n = 126, 97 male and 29 female) and 1028 non-athletic controls (Japanese, n = 407; Polish = 621) who were genotyped for the MCT1 T1470A polymorphism (rs1049434) using the TaqMan SNP genotyping assay or restriction enzyme. The frequency of the TT genotype and T allele was significantly higher in climbers than in controls among the Polish subjects (genotype: p = 0.030, allele: p = 0.010); however, there were no significant differences in the genotype and allelic frequencies between the Japanese climbers and controls (genotype: p = 0.968; allele: p = 0.803). Our results suggested that the frequency of the T allele (TT+TA genotype) in the MCT1 T1470A polymorphism is over-represented in Polish climbers but not in Japanese climbers. In addition, the frequency of the T allele and TT genotype in Polish lead climbers is higher than that in controls.

18.
Plants (Basel) ; 9(6)2020 May 27.
Article in English | MEDLINE | ID: mdl-32471114

ABSTRACT

Self-supporting plants and climbers exhibit differences in their structural and biomechanical properties. We hypothesized that such fundamental differences originate at the level of the material properties. In this study, we compared three non-woody members of the Solanales exhibiting different growth habits: (1) a self-supporting plant (potato, Solanum tuberosum), (2) a trailing plant (sweet potato, Ipomoea batatas), and (3) a twining climber (morning glory, Ipomoea tricolor). The mechanical properties investigated by materials analyses were combined with structural, biochemical, and immunohistochemical analyses. Generally, the plants exhibited large morphological differences, but possessed relatively similar anatomy and cell wall composition. The cell walls were primarily composed of hemicelluloses (~60%), with α-cellulose and pectins constituting ~25% and 5%-8%, respectively. Immunohistochemistry of specific cell wall components suggested only minor variation in the occurrence and localization between the species, although some differences in hemicellulose distribution were observed. According to tensile and flexural tests, potato stems were the stiffest by a significant amount and the morning glory stems were the most compliant and showed differences in two- and three-orders of magnitude; the differences between their effective Young's (Elastic) modulus values (geometry-independent parameter), on the other hand, were substantially lower (at the same order of magnitude) and sometimes not even significantly different. Therefore, although variability exists in the internal anatomy and cell wall composition between the different species, the largest differences were seen in the morphology, which appears to be the primary determinant of biomechanical function. Although this does not exclude the possibility of different mechanisms in other plant groups, there is apparently less constraint to modifying stem morphology than anatomy and cell wall composition within the Solanales.

19.
Ecology ; 101(5): e03004, 2020 05.
Article in English | MEDLINE | ID: mdl-32100291

ABSTRACT

Lianas, woody climbing plants, are increasing in many tropical forests, with cascading effects such as decreased forest productivity, carbon sequestration, and resilience. Possible causes are increasing forest fragmentation, CO2 fertilization, and drought. Determining the primary changing species and their underlying vital rates help explain the liana trends. We monitored over 17,000 liana stems for 13 yr in 20 ha of old-growth forest in the Congo Basin, and here we report changes and vital rates for the community and for the 87 most abundant species. The total liana abundance declined from 15,007 lianas in 1994 to 11,090 in 2001 to 9,978 in 2007. Over half (52%) of the evaluated species have significantly declining populations, showing that the community response is not the result of changes in a few dominant species only. Species density change (i.e., the change in number of individuals per hectare) decreased with mortality rate, tended to increase with recruitment rate, but was independent of growth rate. Species change was independent of functional characteristics important for plant responses to fragmentation, CO2 , and drought, such as lifetime light requirements, climbing and dispersal mechanism, and leaf size. These results indicate that in Congo lianas do not show the reputed global liana increase, but rather a decline, and that elements of the reputed drivers underlying global liana change do not apply to this DR Congo forest. We suggest warfare in the Congo Basin to have decimated the elephant population, leading to less disturbance, forest closure, and declining liana numbers. Our results imply that, in this tropical forest, local causes (i.e., disturbance) override more global causes of liana change resulting in liana decline, which sharply contrasts with the liana increase observed elsewhere.


Subject(s)
Trees , Tropical Climate , Carbon Sequestration , Congo , Forests , Humans
20.
Eur J Sport Sci ; 20(4): 427-436, 2020 May.
Article in English | MEDLINE | ID: mdl-31258054

ABSTRACT

Kinesio taping (KT) is a commonly used intervention in sports and, recently, KT has become popular among athletes competing in sport climbing and bouldering events. However, evidence on the effect of KT on grip strength and endurance is still controversial. Therefore, the purpose of this study was to evaluate immediate effects of KT on muscular strength and endurance of the finger flexor muscles in sport climbers. Twenty recreationally-trained active sport climbers (10 men, 10 women) aged 28.5 ± 10.6 years performed one familiarisation trial and subsequently, in a randomised crossover design, two test trials either with (TAPE) or without (CONTROL) KT over the finger flexor muscles. Test trials consisted of three performance measurements (hand grip strength and endurance, finger hang, and lap climbing) at intervals of 48 h in a randomised order. We observed no significant differences in the parameters of hand grip peak force, fatigue index, finger hang time, lap climbing distance and time, or maximum blood lactate values after lap climbing between the TAPE and CONTROL trials (p > 0.05). The participants' climbing ability was significantly correlated with the intra-individual performance changes between the TAPE and CONTROL conditions for the fatigue index (r = -0.598, p = 0.005), but not in any of the other performance-related parameters. Therefore, KT over the finger flexor muscles neither enhanced hand grip strength and endurance nor the sport climbing performance parameters of finger hang, lap climbing distance and time, and maximum blood lactate values after lap climbing.


Subject(s)
Athletic Tape , Hand Strength , Mountaineering , Physical Endurance , Adolescent , Adult , Cross-Over Studies , Female , Humans , Male , Muscle Fatigue , Young Adult
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