Mountain biking (MTBing) has become one of the most popular recreational activities and this trend is further amplified with the enhanced use of electrically assisted mountain bikes (eMTBing). While ...increasing user frequencies are intensifying social and environmental conflicts, the consequences of MTBing in and for the environment are insufficiently understood. The aim of this review is to outline the ecological impacts of conventional mountain biking and to highlight potential differences and consequences arising with the use of eMTBs.
The results systematically summarise how MTBing can lead to immediate responses of animals, changes in habitat use and diurnal activity patterns of wildlife, a reduced reproductive success, seed dispersal, trampling damage on flora, vegetation changes in areas adjacent to trails, as well as soil compaction, exposure and erosion. The increasing use of eMTBs will cause a larger frequency and spatial cover by bikers and therefore a rising number of trails. Wildlife will be more affected when off-trail riding increases or when the use of so far less frequented areas or times will intensify. Vegetation and soil will be more affected, when new trails are created. Both aspects are more likely with the switch to eMTBing as steep slopes are climbed faster and more frequently. However, these direct effects of MTBing may not be associated with negative long-term consequences for ecosystems as those depend on the specific species or subjects of protection, the environmental context and possible interactions with other human activities. Overall, long-term consequences for plants and animals are difficult to assess and thus general patterns of how the direct effects of (e)MTBing translate into consequences for population dynamics are yet missing. It is essential to improve the knowledge regarding long-term effects of (e)MTBing on the population and ecosystem level and societal debates regarding (e)MTBing need to differentiate effects relevant for animal welfare from implications for nature conservation.
•MTB affects soil, vegetation and wildlife, which may intensify with a switch to eMTB.•Lack of knowledge on riding behaviour and preferences as well as user group in eMTB.•Lack of research on long-term effects of (e)MTB for vulnerable species and ecosystems.
Invertebrate herbivores are ubiquitous in most terrestrial ecosystems, and theory predicts that their impact on plant community biomass should depend on diversity and productivity of the associated ...plant communities. To elucidate general patterns in the relationship between invertebrate herbivory, plant diversity, and productivity, we carried out a long-term herbivore exclusion experiment at multiple grassland sites in a mountainous landscape of central Germany. Over a period of five years, we used above- and belowground insecticides as well as a molluscicide to manipulate invertebrate herbivory at 14 grassland sites, covering a wide range of plant species diversity (13-38 species/m
2
) and aboveground plant productivity (272-1125 g·m
−2
·yr
−1
), where plant species richness and productivity of the sites were not significantly correlated.
Herbivore exclusion had significant effects on the plant communities: it decreased plant species richness and evenness, and it altered plant community composition. In particular, exclusion of belowground herbivores promoted grasses at the expense of herbs. In contrast to our expectation, herbivore effects on plant community biomass were not influenced by productivity. However, effect size of invertebrate herbivores was negatively correlated with plant diversity of the grasslands: the effect of herbivory on biomass tended to be negative at sites of high diversity and positive at sites of low diversity. In general, the effects of aboveground herbivores were relatively small as compared to belowground herbivores, which were important drivers of plant community composition. Our study is the first to show that variation in the effects of invertebrate herbivory on plant communities across a landscape is significantly influenced by plant species richness.
Arthropod abundance has been hypothesized to be correlated with plant diversity but the results of previous studies have been equivocal. In contrast, plant productivity, vegetation structure, abiotic ...site conditions, and the physical disturbance of habitats, are factors that interact with plant diversity, and that have been shown to influence arthropod abundance. We studied the combined effect of plant species diversity, productivity and site characteristics on arthropod abundance in 71 managed grasslands in central Germany using multivariate statistics. For each site we determined plant species cover, plant community biomass (productivity), macro- and micronutrients in the soil, and characterized the location of sites with respect to orographic parameters as well as the current and historic management regimes. Arthropods were sampled using a suction sampler and classified a priori into functional groups (FGs). We found that arthropod abundance was not correlated with plant species richness, effective diversity or Camargo's evenness, even when influences of environmental variables were taken into account. In contrast, plant community composition was highly correlated with arthropod abundances. Plant community productivity influenced arthropod abundance but explained only a small proportion of the variance. The abundances of the different arthropod FGs were influenced differentially by agricultural management, soil characteristics, vegetation structure and by interactions between different FGs of arthropods. Herbivores, carnivores and detritivores reacted differently to variation in environmental variables in a manner consistent with their feeding mode. Our results show that in natural grassland systems arthropod abundance is not a simple function of plant species richness, and they emphasize the important role of plant community composition for the abundance patterns of the arthropod assemblages.
Understanding the driving forces affecting species occurrences is a prerequisite for determining the indicator suitability of crenic plants. We analysed 18 environmental variables in a two-step ...approach, evaluating their ability to explain the species composition of 222 springs on five siliceous mountain ranges, in central Germany and north-west Czech Republic (49.9°–50.8°N, 10.6°–12.8°E). First, we identified the significant environmental variables in three subsets of spatial, hydrophysical and hydrochemical variables using a forward-selection procedure. We then performed a partial canonical correspondence analysis (pCCA) to estimate the influence of each subset alone, as well as in combinations. We also used a multiple response permutation procedure (MRPP) to compare the five regions with respect to the dissimilarity of their vegetation composition and environmental variables. Hydrochemical factors played a fundamental role in determining the plant community of the investigated springs. Spatial factors, in particular altitude, were correlated with the hydrochemical factors, but were less important. Hydrophysical factors played only a marginal role. More precisely, species occurrence was mainly driven by a gradient of nutrient availability, which in turn reflected the acidity status. This gradient was primarily represented by high Al, Cd, and Mn concentrations in acidic crenic waters, high Ca and Mg concentrations were encountered in circumneutral springs. By comparing the five regions we could show that there are spatial patterns in the vegetation of springs, which provide valuable ecological information on the water quality. We therefore suggest that biomonitoring approaches to vegetation are suitable for revealing the acidity status of springs and their forested catchments.
Spring water reflects the hydrochemistry of the aquifer in the associated catchments. On dense siliceous bedrock, the nearsurface groundwater flow is expected to be closely related to the ...biogeochemical processes of forest ecosystems, where the impact of land use is also low. We hypothesize that the plant species composition of springs mainly reflects hydrochemical conditions. Therefore, springs may serve as indicator systems for biogeochemical processes in complex forest ecosystems. To test this hypothesis, we investigate the influence of spring water chemical properties, catchment traits, and spatial position on plant species composition for 73 springs in forested catchments in central Germany, using non-metric multidimensional scaling (NMDS), Mantel tests, and path analyses. Partial Mantel tests and path analyses reveal that vegetation is more greatly influenced by spring water chemistry than by catchment traits. Consequently, the catchment's influence on vegetation is effective in an indirect way, via spring water. When considering spatial aspects (in particular altitude) in addition, the explanatory power of catchment traits for spring water properties is reduced almost to zero. As vegetation shows the highest correlation with the acidity gradient, we assume that altitude acts as a sum parameter that incorporates various acidifying processes in the catchment. These processes are particularly related to altitude – through bedrock, climatic parameters and forest vegetation. The species composition of undisturbed springs is very sensitive in reflecting such conditions and may serve as an integrative tool for detecting complex ecological processes.
Effective visitor management requires reaching visitors with fitting information at the right time through the channels they already use. To identify effective communication channels, 410 ...recreationists were interviewed in north-east Bavaria to determine how they plan and navigate their outdoor activities. Interviews were conducted onsite (38%) as well as through digital media (62%). The study found that the majority of people use digital tools when planning (86%) and navigating (73%) outdoor activities. Additionally, most people (84%) use more than one tool for planning activities, while almost half (48%) use only one tool for navigation. The choice of tools was largely influenced by the planned activity. Trail running (93%), mountain biking (93%), and hiking (84%) were mostly planned using a digital main tool, while sport climbing was mainly planned using an analog main tool (57%), with 87% of sport climbers using printed guidebooks. Age had a smaller effect on tool choice, with 90% of 30-year-olds using a digital main tool for planning outdoor activities compared to 73% of 60-year-olds. The study demonstrates the importance and the diversity of digital tools used for outdoor activities that need to be considered for effective visitor management in tourism as well as nature conservation.
Atmospheric acidic depositions have strongly altered the functioning and biodiversity of Central European forest ecosystems. Most impacts occurred until the end of the 20th century but the situation ...substantially improved thereafter caused by legal regulations in the late 1980's to reduce acidifying atmospheric pollution. Since then slow recovery from acidification has been observed in forested catchments and adjacent waters. However, trends of recovery are inconsistent and underlying mechanisms diminishing recovery are still poorly understood.
We propose that the input of road salt can significantly affect acidity regime and acidification recovery of forest ecosystems.
By comparing the discharge hydro-chemistry and plant community composition of springs fed by forested catchments with and without high levels of salt input over two decades we observed a significant suppression of recovery and elevated levels of nutrient leaching (K+, Ca2+ and Mg2+) in highly salt contaminated catchments.
We show that the pollution of near-surface groundwater (interflow) by road salt application can have lasting effects on ecosystem processes over distances of several hundred metres apart from the salt emitting road.
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•Road salt significantly affects acidity regime of road adjacent forest catchments.•Peak water concentrations of Na and Cl occurred during snowmelt periods (April/May).•Water concentrations of Na and Cl remained constantly high throughout the whole year.•Road salt seems to increase the leaching of soil cation nutrients (K, Mg and Ca).•Effects were detectible up to a distance of 830m from the road.
The number of people riding mountain bikes (MTBs) with electrical assistance (eMTB) is growing rapidly, creating a substantial switch from conventional mountain biking to electrically assisted ...mountain biking. Electrical support has the potential to alter riding behaviour on mountain bikes, associated with a change in destination choice and physiological demand. Hence, this study conducted test rides with 10 sport science students riding on conventional and electrically assisted mountain bikes with the purpose to examine how electrical assistance affects the spatio-temporal riding parameters mean speed, total distance, total climb and surface type. In addition, we recorded the physiological parameter heart rate and calculated the energy expenditure when riding conventional MTBs and eMTBs. We found higher speed associated with longer distance and elevated climb on eMTBs, combined with a higher percentage in the use of singletrails. At the same time, participants riding mountain bikes with electrical assistance showed lower heart rates and lower energy expenditure. Moreover, our results indicate that e-assisted participants are able to reach higher altitudes despite a lower endurance performance. Accordingly, the increasing use of eMTBs is leading to an augmentation of the movement capacity of people in natural mountain areas and thus, promoting physical activity and nature experiences on the one hand. However, a higher number of people in sensitive natural systems is also related to increasing risks for flora and fauna, particularly when riding gets “faster - higher – farther”. Informing people about the risks to increase awareness and promote appropriate behaviour in combination with the setting of a proper trail management, is of crucial importance to successfully merge recreation and nature protection in mountain systems.
This study reveals clear differences in riding behaviour, trail choice and physiological response when riding conventional mountainbikes and mountainbikes with electrical assistance in mountain systems. With electrical assistance allowing less restricted access to physically demanding terrain, an increasing number of mountain bikers may reach sensitive ecosystems in high altitudes. To minimise ecological consequences such as vegetation damage and disturbance of wildlife, it is vital to adequately adjust management solutions. Our results highlight the need for clear regulations and informing of people, translating into a considerate and sustainable behaviour and trail choice and hence the prevention of conflicts with nature conservation and human stakeholders like recreationists or farmers.
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•Riding mountain bikes with electrical support implicates higher mean speed and a strong tendency to ride higher and farther.•The proportion of riding on singletrails is higher when using electrically-assisted mountain bikes.•On eMTBs, less physical energy is demanded and less time is spent above the individual anaerobic threshold.•People with eMTBs are able to reach higher altitudes despite a lower endurance performance.
•Cross-country ski track preparation affects soil properties and flowering phenology.•Similar abiotic but differing biotic effects of mid and high elevation ski tracks.•Cross-country skiing may ...enhance diverse species compositions in landscapes.
Space requirements by winter sports and accelerating global warming are usually perceived as stressors for mountain meadow plant communities. Cross-country ski track preparation (i.e. grooming), however, might retard effects of climate change and, being limited in space requirements, might increase abiotic heterogeneity. The effect of cross-country ski tracks on meadow vegetation was quantified along a representative ski track that had been operated for 30 years in the Fichtelgebirge, a low mountain range in central Europe. Paired sampling was implemented to assess the effect of skiing operations on snow and soil properties, plant phenology, biomass production and species composition. Additionally, boosted regression tree analyses were used to quantify the relative importance of the cross-country ski track compared to other environmental conditions.
The cross-country ski track strongly increased snow density, enhanced soil frost, and retarded snowmelt, thereby delaying flower phenology (by 2.1 days) and the early development stages of plant species on the track. However, biomass, species richness and species composition were unaffected by skiing operations except for one species (Leontodon autumnalis) showing exclusive occurrence on the track while four others showed reduced relative occurrence on the track.
While snow and soil properties were influenced by cross-country ski track preparation, natural environmental variability was more influential for species composition and biomass production than the ski track. We therefore conclude that the ski track – without artificial snow – did not negatively affect species composition. By delaying flower phenology, effects of the ski track even counteracted global warming to some degree. Due to their small spatial extent in the landscape, these ski tracks may add to environmental heterogeneity and thus support sustaining diverse species compositions during environmental changes.