Rock climbing is among the outdoor activities that have undergone the highest growth since the second half of the 20th century. As a result, cliff habitats, historically one of the least disturbed by ...human colonization worldwide, are facing more intense human pressure than ever before. However, there is little data on the impact of this activity in plant-communities, and such information is indispensable for adequate manager decision-making. The goal of this study was to determine the impact of rock climbing on plant communities in terms of cover, richness, and composition in relation to climbing intensity on typical Mediterranean limestone cliffs. Three rock-climbing sites were selected in the Baetic range (SE Spain), corresponding to qualitative categories of climbing frequentation: i)"low" (low frequentation with intermittent climbing), ii)"medium" (high frequentation without overcrowding), and iii) "high" (high frequentation with overcrowding). Within each site, we selected climbing routes and adjacent areas free of climbing, then we carried out a photoplot-based sampling by rappelling. We analysed the images to calculate: richness, species cover, and total cover. This study shows that rock climbing negatively affected the cliff plant community at all three study sites. A significant decrease in plant cover, species richness and a shift in the community composition were recorded for climbed areas, the cover being the variable most sensitive to rock climbing. Impact observed proved to be related to the frequentation level. Low-frequentation sites, with usually more specialized climbers, underwent relatively mild damages, whereas at high frequentation sites the impact was severe and the conservation of the species, especially rare ones, became jeopardized. Our study is the first one available to investigate climbing impact on plant communities in Mediterranean areas, but more research on the impact of rock climbing is needed to assess the regulation of this activity. Regarding management guidelines, we propose a management guideline protocol to evaluate climbing routes and design: i) "Sites free of climbing", ii) "Strictly regulated climbing routes", iii) "Mildly regulated climbing routes", or iv) "Free climbing routes".
Questions
Plant communities are shaped by interactions between natural and anthropogenic disturbances and underlying environmental conditions. We asked how disturbance by rock climbing alters ...patterns of cryptogam species diversity and composition along elevational abiotic gradients.
Location
Red River Gorge, Kentucky, United States of America.
Methods
Surveying was completed within 19 climbing routes on sandstone “slabs.” Quadrats were placed at three different vertical positions (elevations) and three different horizontal positions (center of the route, route margin, off‐route). The former provides a gradient of light and moisture availability while the latter corresponds to climbing impact. Cryptogam species cover was visually assessed in all quadrats. Quadrat microtopography was quantified as well as route‐level Heat Load Index and Climbing Use Intensity. We assessed differences in species richness and Shannon diversity (H) among quadrat positions and evaluated differences in species and cryptogam morphological type abundance and composition.
Results
Significant differences existed in richness H, and total cryptogam abundance between quadrat vertical and horizontal positions with a significant interaction between these two factors. Cryptogram abundance was greatest in off‐route quadrats and increased with elevation in such settings. Abundance was consistently lower in on‐route quadrats and, here, did not change with elevation. Richness and H were greatest in off‐route quadrats and declined with increasing elevation in on‐route quadrats. Significant differences in community composition existed as a function of vertical and horizontal position. On‐route quadrats were associated with crustose and granulose species, while foliose and squamulose lichens, and bryophytes were associated with off‐route quadrats.
Conclusions
Cryptogam composition and abundance were associated with varying intra‐route environmental conditions, and off‐ to on‐route disturbance gradients. There is potential for substantive impacts on the ecology of cliff face ecosystems from climbing. Impacts could be reduced by spacing routes widely and avoiding impacts on upper elevations where diversity and abundance are greatest.
Anthropogenic disturbances like rock climbing interact with environmental conditions to affect plant communities. This creates management challenges where disturbance impacts are non‐randomly distributed. Using a novel sampling strategy that overcomes biases in comparison of climbed and unclimbed cliff faces, we demonstrate climbing causes significant reductions in cryptogam abundance and richness. The magnitudes of effects were associated with stress gradients and disturbance intensity.
Abstract
Human activity drastically transforms landscapes, generating novel habitats to which species must adaptively respond. Consequently, urbanization is increasingly recognized as a driver of ...phenotypic change. The structural environment of urban habitats presents a replicated natural experiment to examine trait–environment relationships and phenotypic variation related to locomotion. We use geometric morphometrics to examine claw morphology of five species of Anolis lizards in urban and forest habitats. We find that urban lizards undergo a shift in claw shape in the same direction but varying magnitude across species. Urban claws are overall taller, less curved, less pointed and shorter in length than those of forest lizards. These differences may enable more effective attachment or reduce interference with toepad function on smooth anthropogenic substrates. We also find an increase in shape disparity, a measurement of variation, in urban populations, suggesting relaxed selection or niche expansion rather than directional selection. This study expands our understanding of the relatively understudied trait of claw morphology and adds to a growing number of studies demonstrating phenotypic changes in urban lizards. The consistency in the direction of the shape changes we observed supports the intriguing possibility that urban environments may lead to predictable convergent adaptive change.
The traditional chassis has the problems of low trafficability and poor stability under complex and changeable unstructured conditions. Thus, a wheel rail composite chassis is proposed. The chassis ...had a tracked travel mechanism at the front wheels and a wheeled travel mechanism at the rear wheels. This study presents the design, theoretical analysis and dynamic simulation analysis of the chassis. The maximum values of the passability of the wheel–track composite chassis that can be passed were calculated according to the relevant parameters. Furthermore, the chassis was modeled and simulated using RecurDyn to verify whether the values were reasonable. According to different values of the terrain, slope, vertical obstacle height and trench width, the change regularity of the track tension and driving torque of the chassis were obtained. The chassis is designed to improve the vehicle’s ability to operate under complex and diverse unstructured conditions.
The aim of the study was the process of studying the phenomenon of rock climbing development as one of the promising areas of sports tourism in the Almaty region of the Republic of Kazakhstan, which ...has a wide range of tourist resources systematically involved in various types of tourism. The research method was a large-scale, extended analysis of the tourist attractiveness of the region, and thus defined the most popular tourism destinations, as well as the persistent association of the Almaty region with mountain and foothill terrain, sports tourism and rock climbing. As a result of the research, the authors have formed a clear understanding of rock climbing as one of the promising areas for the development of sports tourism, which is currently becoming increasingly popular among both the local population and tourists of different ages. Sports tourism, rock climbing on natural and artificial (specially created) terrain, requires significant resource provision with respect to both the rock climbing sites, and professional personnel in the field of tourism who possess competencies in the field of sports tourism, ensuring the implementation of this tourist service. The results of the research presented in this article are based on the professional activities of the authors and allow them to have a qualitative impact on the process of training the sports tourism personnel, and contribute to the development of different-level routes for tourists wishing to engage in rock climbing, expand the involvement of tourists and contribute to the development of touristic attractiveness of the regions of the country.
Canonically, each Purkinje cell (PC) in the adult cerebellum receives only one climbing fiber (CF) from the inferior olive. Underlying current theories of cerebellar function is the notion that this ...highly conserved one-to-one relationship renders Purkinje dendrites into a single computational compartment. However, we discovered that multiple primary dendrites are a near-universal morphological feature in humans. Using tract tracing, immunolabeling, and in vitro electrophysiology, we found that in mice ~25% of mature multibranched cells receive more than one CF input. Two-photon calcium imaging in vivo revealed that separate dendrites can exhibit distinct response properties to sensory stimulation, indicating that some multibranched cells integrate functionally independent CF-receptive fields. These findings indicate that PCs are morphologically and functionally more diverse than previously thought.
This paper describes a novel stair-climbing wheelchair operated by human upper body using lever propelled rotary-legs with posture transition mechanism. The design principle of this wheelchair is to ...make use of the user's latent upper body capability, with appropriate mechanisms to enable extended functionality of the regular wheelchair without the need of heavy, expensive mechanisms or electric motors. An arm-operated mechanism allows the user to overcome steps and stairs independently without any external power source. The developed wheelchair consists of manual wheels with casters for planar locomotion, which provides capabilities equivalent to a regular manual wheelchair. In addition, the wheelchair has a rotary-legs mechanism based on lever propulsion control for climbing stairs. It also has a passive mechanism powered by gas springs for posture transition to shift the user's center of gravity between two positions for planar locomotion and for stair-climbing. The proposed design consists of only passive components, which makes the wheelchair more compact and lightweight. In this paper we describe in detail the development of this wheelchair and an investigation of how users can climb stairs independently. We also present evaluation experiments with a healthy participant and a dummy to investigate the feasibility of the proposed design.
Organisms make decisions when they perceive cues of varying intensities. In case of climbing plants, the diameter of supports in contact (tree or stem) is an important cue for their growth as plants ...that coil around a support with large diameter are unable to maintain tensional forces required for continued attachment to the support. The negative association between the diameter and the climbing success has been reported since Darwin published his study on climbing plants. However, it is not known if a climbing plant makes a decision to avoid a support with larger diameter. Here, we tested this possibility by observing the coiling response of tendrils of Cayratia japonica to supports with different diameters. The coiling success of the tendrils was affected by the diameter of the support and the tendril lengths. We propose a decision tree to describe the different phases of the coiling response and demonstrated that the tendrils change their coiling shape depending on the support diameter and the tendril length. To understand the behavioural rules regulating the phase pattern, we constructed a simple model with two assumptions on the tendril movement, (1) when the tendrils receive a contact stimulus, they begin to coil from around the contact point and (2) there is a minimum coiling angle at which the tendrils coil up, once the tendril starts coiling. Image analysis and 3D motion tracking technique revealed that the movement of the tendrils were consistent with the two assumptions of the model. The results suggested that the tendrils flexibly changed the coiling shapes depending on the support diameter and simple behavioural rules could regulate this diameter-dependent response.
Facial Emotion Recognition (FER) is an important research domain which allows us to provide a better interactive environment between humans and computers. Some standard and popular features extracted ...from facial expression images include Uniform Local Binary Pattern (uLBP), Horizontal-Vertical Neighborhood Local Binary Pattern (hvnLBP), Gabor filters, Histogram of Oriented Gradients (HOG) and Pyramidal HOG (PHOG). However, these feature vectors may contain some features that are irrelevant or redundant in nature, thereby increasing the overall computational time as well as recognition error of a classification system. To counter this problem, we have proposed a new feature selection (FS) algorithm based on Late Hill Climbing and Memetic Algorithm (MA). A novel local search technique called Late Acceptance Hill Climbing through Redundancy and Relevancy (LAHCRR) has been used in this regard. It combines the concepts of Local Hill-Climbing and minimal-Redundancy Maximal-Relevance (mRMR) to form a more effective local search mechanism in MA. The algorithm is then evaluated on the said feature vectors extracted from the facial images of two popular FER datasets, namely RaFD and JAFFE. LAHCRR is used as local search in MA to form Late Hill Climbing based Memetic Algorithm (LHCMA). LHCMA is compared with state-of-the-art methods. The experimental outcomes show that the proposed FS algorithm reduces the feature dimension to a significant amount as well as increases the recognition accuracy as compared to other methods.
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