Ski Run Research Articles

How does ski infrastructure change soil erosion processes on hillslope?

AbstractSki tourism's popularity is driving a rise in the number of ski resorts. This study aims to present the impact of ski infrastructure on soil erosion processes in the example from a small catchment in the Gubałowskie Foothills in southern Poland, where landscape changes before (since 1879) and after the construction of the ski station (2007) are presented. The analyses of changes in flow accumulation, slope morphometry, and drainage ditches were conducted in the test area. Quantitative analyses were performed using repeated DEMs derived from aerial LiDAR survey and detailed geodetic measurements, complemented by geomorphological mapping done in the field. The study has revealed that the ski infrastructure has not only directly transformed the hillslope by flattening and constructing escarpments (up to 3 m high) but has also created alternating patterns of erosion and accumulation. In the test area, the drainage ditch was poorly designed. It was filled with materials (0.1–0.5 m), and two new outlets formed. The escarpment of the analyzed ski run has been diminished by 0.5 m. An alluvial fan (0.1–0.22 m thick) has developed on the flattened surface below the escarpment with drainage ditch outlets. This fan is eroded by subsurface flow that creates a piping system. The gully below the alluvial fan has retreated upslope, accelerated by subsurface erosion. This study enables the presentation of hillslope adjustments and processes in response to the new conditions caused by ski infrastructure. Such results may support more effective land management in regions changed by ski infrastructure.

Novi lokaliteti vrste Cirsium candelabrum (Asteraceae) u Hrvatskoj

Cirsium candelabrum is a Balkan endemic species, non-indigenous to Croatia. In the last 13 years its spread was observed only in Central Dalmatia. From 2015 to 2021 we have been recording its invasive spreading across the Kvarner region and its arrival to the southern edge of Gorski Kotar. The plants appear in diverse numbers in two different habitat types. In the sub-Mediterranean zone, the species inhabits ruderal habitats arising from the degradation of the natural vegetation by the construction works for traffic and communal infrastructure and the erection of industrial zones and shopping centres, accompanied by numerous invasive alien species. In the upper (montane and subalpine) zone of Mali and Veliki Platak, C. candelabrum dominates in stands on gravely road edges, forest ways, on incisions with glacial till, and especially luxuriant and dense populations form on the dug-up soil under the ski lift and along the ski run on Radeševo. Here, C. candelabrum is accompanied by native species characteristic for the forest edges and clearings and sometimes for ruderal, chasmophytyc or scree habitats.

Soil function assessment in high‐mountain environments: Testing the SEPP tool in a ski resort in the Italian Alps

AbstractSoil function assessment (SFA) plays an important role in evaluating the impact of management practices, land‐use changes and construction work. The Soil Evaluation for Planning Procedures (SEPP) tool is one of the few existing SFA tools that allow automated SFA. It was originally developed to address land‐use planning issues, which traditionally play a minor role in high‐mountain areas. Hence, the SEPP tool has not yet been applied to such environments. In this study, we tested the SEPP performance on high‐mountain soils previously altered by construction work and land‐use changes. Specifically, we evaluated soil data from 16 ski runs and 16 paired control sites in the Italian Alps, aiming to reflect land‐use‐driven differences in soil properties in the SFA results. The study revealed options to adapt SEPP assessment methods if high‐mountain soils with special characteristics (e.g. shallowness or high coarse fragment content) are investigated. The main adaptation options are the consideration of further soil parameters and the adjustment of thresholds of function fulfilment levels. However, the assessment results of the current SEPP version already reflect the most relevant impacts of ski run construction on the soils in the study area: fulfilment of some of the soil functions was impaired and that of others improved, while most remained at a comparable level. We conclude that SFA with the SEPP tool provides valuable support for the evaluation of construction projects and land‐use change in high‐mountain environments. However, the significance of SFA can be improved by considering the intrinsic properties of high‐mountain soils.

Proposal of an Alpine Skiing Kinematic Analysis with the Aid of Miniaturized Monitoring Sensors, a Pilot Study.

The recent growth and spread of smart sensor technologies make these connected devices suitable for diagnostic and monitoring in different fields. In particular, these sensors are useful in diagnostics for control of diseases or during rehabilitation. They are also extensively used in the monitoring field, both by non-expert and expert users, to monitor health status and progress during a sports activity. For athletes, these devices could be used to control and enhance their performance. This development has led to the realization of miniaturized sensors that are wearable during different sporting activities without interfering with the movements of the athlete. The use of these sensors, during training or racing, opens new frontiers for the understanding of motions and causes of injuries. This pilot study introduced a motion analysis system to monitor Alpine ski activities during training sessions. Through five inertial measurement units (IMUs), placed on five points of the athletes, it is possible to compute the angle of each joint and evaluate the ski run. Comparing the IMU data, firstly, with a video and then proposing them to an expert coach, it is possible to observe from the data the same mistakes visible in the camera. The aim of this work is to find a tool to support ski coaches during training sessions. Since the evaluation of athletes is now mainly developed with the support of video, we evaluate the use of IMUs to support the evaluation of the coach with more precise data.

The influence of speed and strength abilities on the overall endurance of children aged 13-14 years with different typologies

AIM: The aim of this study was to determine the effect of a set of speed-strength exercises on the development of general endurance in schoolchildren aged 13–14, taking into account the differentiated load. METHODS: The pedagogical experiment was conducted on the basis of secondary school 60 in Kirov, Russia. The study involved 40 schoolchildren from the 7th grade, who were differentiated into the control and experimental groups of 20 people in each class. Children from the control group (CG) were engaged in physical education according to the standard program, and children from the experimental group additionally performed exercises for the development of speed and strength abilities with different loads. The strength of the nervous system was determined by tapping test, speed-strength abilities were determined by tests – flexion and extension of the arms at the stop while lying on the floor, long jump from a place with a push with two legs, and lifting the torso from the supine position. Overall endurance was determined by the “3 km ski run” test. RESULTS: In the CG, there was an improvement of only 2–4%. In the experimental group, there were significant improvements of 11–16%. CONCLUSION: I f schoolchildren perform exercises for the development of speed and strength abilities at physical education classes at school every time, then not only the indicators of these abilities will improve, but also the indicators of the overall endurance of children aged 13–14 will improve. Our results allow us to supplement the standard physical education program at school and effectively develop the physical qualities of schoolchildren aged 13–14.

ЖЕЛЕЗНЫЙ ЧЕРЕШКОВЫЙ НАКОНЕЧНИК СТРЕЛЫ МОНГОЛЬСКОГО ВРЕМЕНИ ИЗ С. РЕБРИХА

The present article is devoted to the characteristics of the iron tanged arrowhead of the Mongolian period and the place where this artifact was found. The arrowhead was found by V.V. Tolstopyatov in the summer of 2018 at the edge of a pine forest on the right side of the Kasmala river valley. In this place, the surface was partially destroyed during the preparation of the ski run and the arrowhead was on the surface. The special features of the product allow us to date it to the Mongolian time (the 13th -14th centuries AD) and to refer it to the Karmatskaya culture that was common in the Altai Territory. The arrowhead was most likely lost by the archer together with the arrow during a conflict. This fact is confirmed by a rather good condition of the item and its surface, which is common for the so-called “accidental finds” of Mongolian iron items; 16 such items are known in the region.

Recent thermokarst evolution in the Italian Central Alps

AbstractThermokarst depressions are widespread phenomena due to permafrost degradation in the Arctic, whereas only few are known from mountain permafrost of the mid‐latitudes. In the Italian Central Alps, close to the Stelvio Pass (2,763 m above sea level), a ski run was built in 1987. Since 1981, statistically significant air warming has been recorded, especially during summer (+0.65°C per decade). Permafrost temperature recorded at the nearby Share Stelvio Borehole between 1990 and 2011 exhibited a rapid increase (> 0.8°C per decade) and an active‐layer thickening (7 cm/year). Between the years 1999 and 2003, some thermokarst depressions started to develop, initially in the lower part of the ski run and then extending to higher elevations. The depressions increased in number, size, and depth with time. Since ski‐run construction, the area remained free of vegetation until early 2000, when vegetation colonization started, showing a coupling with the onset of thermokarst development and summer warming. Vegetation changes accelerated with the ingress of pioneer and early‐successional as well as of late‐successional species. Moreover, the ingress of shrub species (Salix spp.) typical of lower elevation belts (subalpine and even montane) was dated to 2004. All the observed features show a rapid and coupled response of the abiotic and biotic components of this ecosystem to climate warming. Our data also confirm the similarity of the observed responses and dynamics of the alpine tundra with the Arctic tundra with regard to both permafrost and vegetation.

Anthropogenic Impacts on Water Quality in a Small, Forested Mountain Catchment: A Case Study of the Seebächle, Black Forest, Southern Germany

The aims of this case study are to assess water quality in a small, forested mountain catchment in the Black Forest, forming part of a National Park and Natura 2000 zone. Field work was carried out in the catchment of the Seebächle torrent, a small headwater basin of the River Acher, a confluent of the Rhine, in Southern Germany between late winter and early summer of 2018. The catchment has a diverse natural setting of water bodies, including springs, torrents, and a lake, and is impacted by anthropogenic activities such as summer tourism, winter sports, two quarries, road traffic, and an isolated construction site. Physio-chemical and bacterial water samples were obtained at 10 measurement sites, including a spring, a lake (Mummelsee), a fountain, artificial and natural snow on and next to a ski run (Seibelseckle), artificial ditches and parking lots draining the ski run, and the Seebächle torrent above two granite mines. Samples were either taken directly on site or analyzed in corresponding hydrology and hospital microbiology laboratories. Water of the Seebächle is oxygen-rich, peaty, and mostly acidic, but the pH varies between 4.1 and 9.5 throughout the catchment, inclining towards acid in the fountain and below the ski run and towards alkaline in the lake. Conductivity is spatially highly variable, reaching the most elevated values below the ski run and its parking lot (149 µS/cm). A high density of bacteria including enterobacteria was detected at nearly all sites. Human pathogenic bacteria were found below and surrounding the ski run, at parking lots draining the ski run, as well as at the lowest site during the mid-spring campaign. They were also detected in the touristically highly frequented lake and in the spring feeding the lake during the end-of-spring campaign. Whilst most physico-chemical parameters followed a similar pattern and fell within good to very good EU drinking water quality status, the lake turbidity levels (19.2 NTU) by far exceeded norms after ice thawing. The most contaminated site in terms of bacteria and turbidity (5.2 NTU), ammonium nitrogen (0.18 mg/L), and total nitrogen (5.06 mg/L) was the spring feeding the Mummelsee draining the construction site of a new restaurant. These field analyses show that the water quality of a virtually uninhabited, natural headwater catchment is strongly interconnected and can degrade both by direct and indirect impacts of overtourism.

Artificial Snowmaking: Winter Sports Between State-Owned Company Policy and Tourist Demand

Due to changing climatic conditions, artificial snowmaking has become a major method of ski resort adaptation globally. It is a financially intensive operation requiring high start-up investment and involving operating costs that are dependent on weather conditions. Operational costs and the expansion of artificial snowmaking systems increase the price of ski passes. In our work, we analyzed the operations of a public company that operates the largest ski resorts in Serbia and directs the flow of winter sports tourism. We tried to determine, by means of correlation, the extent to which ski pass prices in the biggest winter resort in Serbia are influenced by factors such as natural snow cover, number of tourist overnights, ski run length, and local wages. The results of the survey indicate an increasing transformation of the ski resort into a thematic attraction independent of climatic factors in terms of determining ski pass prices.

Mid and long-term ecological impacts of ski run construction on alpine ecosystems

The proliferation of ski run construction is a worldwide trend. The machine-grading of slopes involved during ski run construction changes the physical, chemical and biological properties of the soil, having significant long-term ecological impact on the environment. Establishing and developing plant communities in these affected areas is crucial in rehabilitating the biotic and abiotic soil environment, while also improving slope stability and reducing the risk of natural hazards. This study evaluates changes in plant-soil properties and the long-term effects of machine-grading and subsequent restoration of ski runs so as to contribute to formulating the best practices in future ski run constructions. Study plots were established in 2000 and re-surveyed in 2017 on ski runs, which had been machine-graded and hydroseeded in the 1990s. Vegetation, root trait and soil surveys were carried out on ski run plots and compared to paired, undisturbed control sites off the ski runs. Plant cover remained unchanged on the ski-runs over time but plant richness and diversity considerably increased, reaching similar levels to undisturbed vegetation. Plant composition moved towards more semi-natural stages, showing a reduction in seeded plants with a comparable increase in the cover of colonizing native species. Root trait results were site-specific showing great variations between the mid and long-term after-effects of machine-grading and revegetation when compared to undisturbed sites. Under long-term management, the soil pH was still higher and the organic C content still lower in the ski runs than in the undisturbed sites, as the aggregate stability. The standard actions applied (machine-grading, storage and re-use of topsoil, hydroseeding of commercial seed mixtures, application of manure soon after seeding and low-intensity grazing) allowed the ecosystem to partially recover in three decades, and even if the soil has still a lower chemical and physical fertility than the undisturbed sites, the plant species composition reveals a satisfactory degree of renaturalization.

Potential negative effects of construction of a high-mountain ski resort in the High Tatras, Slovakia, on breeding bird assemblages

Development of new ski resorts potentially has strong negative impacts on natural ecosystems. The objective of this paper is to analyse the potential effects of a newly proposed ski resort development plan on bird assemblages in the High Tatras Mts. of Slovakia. I tested two hypotheses that total bird abundance, species richness and diversity would decline, due (1) to the removal of tree and shrub vegetation after ski run construction and/or (2) as a result of a negative edge effect (i.e. decline along ski run edge). I censused birds in three presently occurring habitat types [successional forest (n = 26 (number of circular plots)), spruce forest (n = 22) and dwarf pine stands (n = 21) and ski runs (n = 20)] close to proposed resort site. I used a variable circular plot method on two spatial scales with radii of 25 and 50 m (three counts per plot during breeding season in 2018). Circular plot samples from ski runs were taken from the closest existing ski resort with similar environmental conditions in Tatranska Lomnica. I found that total density, species richness and diversity were negatively affected by habitat alterations near this resort, and provided evidence of negative edge effect of ski runs on bird abundance, diversity metrices and evenness. Based on these results and a literature review, I recommend that building new ski resorts not be built in strictly protected areas and that future ski resort developments be restricted to areas that have lower conservation value.

Evaluation of the Quality of Manual, Compression-Only Cardiopulmonary Resuscitation in a Moving Ski Patrol Toboggan.

Introduction: Cardiopulmonary resuscitation (CPR) quality may be impacted by location and setting of an out of hospital cardiac arrest. This study compared the quality of CPR performed on a moving ski patrol toboggan versus stationary CPR, both performed outdoors in winter. Materials and Methods: Compression-only CPR was performed on a manikin attached to a backboard secured into a toboggan. A CPR device was used to measure compression rate, depth and recoil, and elapsed time. A convenience sample of 30 patrollers, in weather-appropriate clothing, participated in this nonrandomized, crossover study. Each first performed 5 continuous sets of 30 compressions of stationary CPR straddling the manikin while kneeling. After 15 minutes rest, participants performed CPR while moving down the designated ski run (fixed length, vertical drop, and slope angles). Each ski run was video captured with a GoPro camera. Quality was defined as compliance with 2015 International Liaison Committee on Resuscitation (ILCOR) guidelines for CPR. Results: Overall, stationary and moving chest compressions complied with ILCOR guidelines, but there was a statistically significant degradation of CPR quality while moving and over time. Fewer compressions met ILCOR guidelines in comparison to stationary CPR compressions: (1) stationary mean depth 87% compliant, moving mean depth 35% compliant, 95% confidence interval: 39-65 (p < 0.001); (2) stationary mean rate 90% while moving mean rate 64% compliant; and (3) stationary recoil 74%, while moving recoil 77% compliant. Noncompliant compressions were typically too shallow, and noncompliance for rate was typically too fast. There were no pauses over 10 seconds once compressions were started. Conclusions: Despite CPR quality being reduced while moving, there were sufficient compliant compressions to support the use of CPR in this setting. Maintaining regular CPR training in a working environment and optimal body position in relation to the patient may be keys to performing high quality CPR on a moving toboggan.

Impact of ski run construction on atypical channel head development.

The development of ski infrastructure in mountainous areas has a significant impact on the development of erosion landforms and modification of existing landforms on slopes. The main purpose of our study was to determine the effects of ski run construction and artificial snowmaking on the development of channel heads and drainage lines as well as pattern of processes occurring along longitudinal profile of stream channel. The research was performed in the Remiaszów catchment on two ski runs in the Białczańska Kotelnica ski area (the Polish Inner Carpathians). Analysis of the location of the channel head of the Remiaszów Stream catchment over time was performed on the basis of multi-temporal DEMs generated using high resolution LiDAR data. The data were obtained via two ALS scans (Airborne Laser Scanning): before the 2013 and after 2016 ski run construction, as well as TLS (Terrestrial Laser Scanning) conducted in 2017 and in the course of fieldwork in 2018 using GPS RTK. The construction of ski runs leads to the formation of new channel heads, all of which develop in drainage ditches. Three distinct zones emerge in the longitudinal profile: 1) artificially concentrated flow zone, 2) forced, dispersed flow zone, 3) rejuvenated, concentrated flow zone. This means that two channel head formation zones become available in the longitudinal profile. Large inflows of water (200% or more) due to artificial snowmaking lead to bidirectional development of the valley network. In general, identification of the channel head pattern in area of ski run construction play important role in understanding of the sustainable development of mountain ecosystem.

The (In)visibility of Groomed Ski Runs.

I analyse the visibility of “groomed” ski runs under different lighting conditions. A model of human contrast sensitivity predicts that the spatial period of groomed snow may render it invisible in the shade or on overcast days. I confirm this prediction with visual demonstrations and make a suggestion to improve visibility.

A method of deriving operation-specific ski run classes for avalanche risk management decisions in mechanized skiing

Abstract. An in-depth understanding of the nature of the available terrain and its exposure to avalanche hazard is crucial for making informed risk management decisions when travelling in the backcountry. While the Avalanche Terrain Exposure Scale (ATES) is broadly used for providing recreationists with terrain information, this type of terrain classification has so far only seen limited adoption within the professional ski guiding community. We hypothesize that it is the generic nature and small number of terrain classes of ATES and its precursor systems that prevent them from offering meaningful assistance to professional decision makers. Working with two mechanized skiing operations in British Columbia, Canada, we present a new approach for deriving terrain classifications from daily terrain assessment records. We used a combination of self-organizing maps and hierarchical clustering to identify groups of ski runs that have been assessed similarly in the past and organized them into operation-specific ski run hierarchies. We then examined the nature of the emerging ski run hierarchies using comprehensive run characterizations from experienced guides. Our approach produces high-resolution ski run hierarchies that offer a more nuanced and meaningful perspective on the available skiing terrain and provide new opportunities for examining professional avalanche risk management practices and developing meaningful decision aids.

Sustainable Soil Management in Ski Areas: Threats and Challenges

The skiing industry often represent the main contribution to mountain regions’ economy, by providing several economic benefits and the improvement of services and infrastructure. Ski resorts also play a crucial role as an impacting factor, causing severe changes on Alpine landscape and ecosystems. In particular ski runs construction and operation have considerable impacts on alpine soils, influencing their chemical and physical properties which affecting the establishment and development of plant communities. The work provides a description of the changes in soil properties and the related effects on vegetation. It aims furthermore to investigate the recent best practices applied for a successful soil restoration after ski runs construction, which may contribute to a sustainable use of mountain soils and ecosystems. Based on the current regulatory framework, this review gives a global overview on how, in Europe and specifically in Italy, the sustainable use of soils is considered during the construction and management of ski runs. As the framework is still lacking of specific rules regarding soil protection and management on ski runs, the present work wishes to provide recommendations in order to fill this gap, favoring the effective application of best practices for soil protection during ski run construction and maintenance.

Ski areas affect Pacific marten movement, habitat use, and density

ABSTRACTAlpine ski recreation is one of the most popular outdoor winter sports globally but often involves habitat modification and dense human activity, both of which can harm wildlife. We investigated the effects of ski area development and winter recreation activities on movement, occupancy, and density of Pacific martens (Martes caurina) in the Lake Tahoe region of California and Nevada, USA by comparing 3 ski and 3 control study areas. We systematically surveyed martens using live traps and hair snares during spring–summer and winter seasons from 2009 through 2011 to identify how martens responded to the year‐round effects of habitat fragmentation from ski area development and the seasonal effects of winter recreation activities. Martens selectively moved between remnant forest patches with the shortest crossing distances across open, non‐forested ski runs in both seasons, with the effect more pronounced in females. Overall, habitat connectivity was reduced by 41% in ski areas compared to habitat not fragmented by ski runs. During spring–summer, occupancy rates were not different between habitat within or outside of ski operations areas. During winter, however, occupancy was significantly lower inside (52%) ski area boundaries than outside (88%) them. Reduced detection probability in ski areas indicated martens also reduced the frequency of use of operations areas in winter. Using spatially explicit capture‐recapture models, we found that marten density did not differ between ski areas and controls during spring, but during winter female density declined at ski areas by 63% compared to spring–summer and was &lt;50% of female density compared to controls. This suggests that females seasonally avoid habitat in ski areas by shifting their habitat use to areas outside ski operations boundaries during winter. Although male marten density did not differ, the lack of resident males &gt;3 years old coupled with higher annual turnover rates suggests male densities at ski areas may be reliant on annual male immigration. In winter, martens avoided using habitat in ski operations areas when recreation activity was greatest. Winter ski recreation may not be incompatible with marten use of habitat in ski areas, but habitat fragmentation from ski areas affects marten movement and recreation activities affect seasonal habitat occupancy and female density. Maintaining functional habitat connectivity, via networks of short ski run crossings that link habitat in and out of ski areas, will be important for maintaining or improving marten use of remnant habitat in developed ski areas. © 2017 The Wildlife Society

Automatic Identification of Subtechniques in Skating-Style Roller Skiing Using Inertial Sensors.

This study aims to develop and validate an automated system for identifying skating-style cross-country subtechniques using inertial sensors. In the first experiment, the performance of a male cross-country skier was used to develop an automated identification system. In the second, eight male and seven female college cross-country skiers participated to validate the developed identification system. Each subject wore inertial sensors on both wrists and both roller skis, and a small video camera on a backpack. All subjects skied through a 3450 m roller ski course using a skating style at their maximum speed. The adopted subtechniques were identified by the automated method based on the data obtained from the sensors, as well as by visual observations from a video recording of the same ski run. The system correctly identified 6418 subtechniques from a total of 6768 cycles, which indicates an accuracy of 94.8%. The precisions of the automatic system for identifying the V1R, V1L, V2R, V2L, V2AR, and V2AL subtechniques were 87.6%, 87.0%, 97.5%, 97.8%, 92.1%, and 92.0%, respectively. Most incorrect identification cases occurred during a subtechnique identification that included a transition and turn event. Identification accuracy can be improved by separately identifying transition and turn events. This system could be used to evaluate each skier’s subtechniques in course conditions.

The effect of heads-up-display (HUD) goggles on skiing and snowboarding speeds

This study empirically explores whether the use of heads-up-display (HUD) goggles increases the risk in ski areas by increasing skiing and snowboarding speeds. Twenty-seven skiers and snowboarders participated in a repeated measures experiment that included a control session without the HUD goggle and three sessions with the HUD goggle under a variety of conditions. The skiing behaviour of each participant was monitored using a Global Positioning System (GPS) tracker. The runs of the ski area were divided into 51 homogeneous run sections and speed quantiles (median to maximum in 5 percentage point intervals) were calculated for each individual pass through these run sections (n=4,451). A mixed-effects model was then applied to examine the effect of HUD goggles on skiing speeds for each quantile in combination with various personal (e.g., skiing ability) and external factors (e.g., terrain). Among the variables tested, ability level had the strongest positive effect on skiing speeds, while terrain characteristics including steep gradients, ungroomed runs, and treed areas, were all associated with slower skiing speeds. No long-term effect of HUD goggle use on skiing speeds was found, but advanced/expert skiers did appear to benchmark ‘personal best’ speeds during first HUD use – particularly on long straight run sections – before returning to slower speeds during subsequent HUD use. Whereas no significant HUD effect was observed among beginners/intermediates, skiing speeds were significantly faster among beginners/intermediates listening to music during the sessions. The potential for distraction as a result of HUD use still requires investigation. Management implications•Considerable growth in the use of smart wearable devices is expected.•The findings of this study suggest that the use of HUD goggles does not cause a persistent increase in skiing speeds.•Ski resort managers might want to examine their existing policies and practices (e.g., patrols, speed warning signs) on long-straight ski run sections to mitigate any safety issues associated with advanced/expert users benchmarking ‘personal best’ speeds during first HUD use.•Ski resort managers may consider HUD goggle technology as an opportunity for providing visitors with geo-targeted information such as lift wait times and slope congestion data that could improve their skiing experience.

Initial disturbance intensity affects recovery rates and successional divergence on abandoned ski slopes

Summary The importance of site history (including initial disturbance intensity and propagule arrival) in determining successional trajectories is a key theoretical and applied line of research in ecology. Abandoned ski slopes provide an opportunity to study successional processes following differing initial disturbance intensities. Some ski slopes are graded with heavy equipment when constructed (‘graded’, severe initial disturbance), while others are simply cleared of tall woody vegetation (‘cleared’, lesser initial disturbance). In a blocked chronosequence study of graded and cleared ski slopes abandoned 10–43 years previously, we found that graded ski slopes did not show predictable recovery trajectories over many decades. In contrast, cleared ski runs showed significant convergence with adjacent reference forest communities. Convergence in community composition on cleared ski runs was driven by trees, though understorey species were more numerous and dominant during succession. Understorey communities did not predictably change in species or life‐form composition over time, regardless of ski run type. Graded ski runs exhibited little or no edaphic recovery over time, showing neither reductions in bare ground and visible soil erosion, nor increases in soil depth. Cleared ski runs, in contrast, showed evidence of recovery in all of these variables except soil depth, which remained uniformly high. Synthesis and applications. The creation of new ski slopes by tree clearing is preferable to the grading of new slopes with heavy machinery, because grading reduces ecosystem function and decreases the predictability of soil and vegetation recovery decades after abandonment. Existing graded ski slopes (both operational and abandoned) may benefit from restoration of soils and vegetation.