Effects of extreme natural events on the provision of ecosystem services in a mountain environment: The importance of trail design in delivering system resilience and ecosystem service co-benefits

Trail sustainability: A state-of-knowledge review of trail impacts, influential factors, sustainability ratings, and planning and management guidance

Protected areas (PAs) provide many important recreational, social, and economic benefits that are largely dependent on their ability to sustain visitation. Trail networks are a critical tourism infrastructure element that directly accommodate high quality recreation activities and experiences while providing access to and protection of irreplaceable natural and cultural resources. Unfortunately, most trail networks consist of historic "legacy" trails that were not sustainably designed and whose intensive use cause unacceptable impacts to PA resources, experiences, and values. This paper provides an international state-of-knowledge review of trail science research within the field of recreation ecology to describe common trail impacts and factors that influence trail degradation that trail stewards can manipulate to enhance the sustainability of trail networks. Two emerging models that seek to rate trail topographic sustainability are presented to illustrate their potential utility to PA managers. Expanding and incorporating trail science research into the sustainable trail planning, design, and Best Management Practice literature are also discussed.

Rehabilitation of eroded trails and gullies on quartzite rock outcrops with native species in a high-altitude grassland

The quartzite rock outcrops and the native vegetation of grasslands located at the Serra da Calçada Mountain in Minas Gerais State (Brazil) have been severely degraded by extreme sports activities such as motocross and off-road vehicles, greatly damaging the abundant headwaters. The main consequences thereof were hilly and gully erosion processes with soil loss and the deviation of the water from its original paths. However, currently, there is no report of successful restoration efforts in severely eroded outcrops in Brazilian high-altitude grasslands (campo rupestre). Through the Universal Soil Loss Equation (USLE), we found a high general erosion rate in the study site (669.91 t·ha^-1·year^-1), and the specific soil loss provoked by off-road vehicles on trails was significantly greater (49 m³ per 100 m²) than that caused by mountain bikes and trekking (5.8 m³ per 100 m²). We performed the physical reconstruction of eroded outcrops and surface water flow paths by allocating locally available quartzite rocks. These rocks were inoculated with different species of bryophytes and planted with native species under two treatments: un-inoculated and inoculated with arbuscular mycorrhizal fungi (AMF) spores of the Rhizophagus irregularis species. After 2 years, the bryophyte communities showed a similar pattern to the preserved site, and the AMF inoculation favoured plant establishment of most species, especially of the Asteraceae, Cyperaceae, Fabaceae, Malpighiaceae, Orchidaceae and Poaceae families. The AMF also improved the soil fertility, highlighting soil P, SOM, CEC, NH₄⁺-N as well as soil water content and water retention capacity. Poaceae family species showed an outstanding occupation, which was considered a functional indicator of rehabilitation success, functioning as a "hydraulic carpet" for water exportation, conduction and drainage across the outcrops. This study provides an eco-technology to restore severely eroded outcrops over headwaters using native species in the Brazilian high-altitude grasslands.

A Review of Village Ecosystem Vulnerability and Resilience: Implications for the Rocky Desertification Control

Under the background of global environmental change, a huge impact has been made on the village ecosystem, which leads to disorder of structure and function of the village ecosystem. The current management measures of the village have failed in allowing the village to achieve sustainable development. Research on the vulnerability and resilience of the village ecosystem is helpful in regards to the ecological restoration of the village. The research status and progress in regards to the vulnerability and resilience of the village ecosystem are not clear, and the summary of research results and problems is insufficient. Based on 87 related literatures, this paper focuses on the current status and progress of village ecosystem vulnerability and resilience research, and reveals the current research results and shortcomings of village ecosystem vulnerability and resilience. We found that: (1) the research on vulnerability and resilience of the village ecosystem is on the rise; (2) the research mainly focuses on the index system, monitoring and assessment, mechanism research and strategy research. The monitoring and assessment research is the most prominent, which mainly discusses the research methods, the vulnerability and the resilience of the village ecosystem; (3) the study area is mainly concentrated in Asia, North America and Africa. Research institutions are mainly institutions of higher learning and research institutes (centers). Finally, this paper finds that major scientific and technical studies such as the construction of indicator systems and the study of governance strategies in the study of vulnerability and resilience of village ecosystems are lagging behind. In future research, we should deepen the research on the concept and connotation of vulnerability and resilience. We must establish a scientific and reasonable research framework for vulnerability and resilience of the village ecosystem. We should also strengthen and improve the index system of vulnerability and resilience of the village ecosystem. We should strengthen research on the impact mechanisms and governance strategies of vulnerability and resilience, and apply the research on vulnerability and resilience to the planning and governance of the village ecosystem.

Soil erosion on mountain trails as a consequence of recreational activities. A comprehensive review of the scientific literature

This article reviews the scientific literature on trail erosion and the magnitude of the erosive processes that occur on mountain trails due to recreational activities, mainly due to hiking. This work is necessary as a result of the increase in hiking and biking in forest, scrubland and grasslands, and the soil and vegetation degradation induced by these activities. We analysed results that have been compiled in the scientific literature, as well as other issues such as the geographical and temporal distribution of the research, the methods applied, the journals where the research was published, the types and quantity of uses of the pathways and the measures undertaken for damage mitigation. This paper highlights that there is a need for harmonization of methods. The results show that soil erosion rates are highly variable, high, and non-sustainable. Trail erosion research is growing at a rate of 3 papers per year and is published in a small group of scientific journals. Six journals published 47% of the papers on trail erosion, which show a high concentration in environmental journals. There are few papers published in the soil science and geomorphology disciplines, although the research topic and the science background are in these two disciplines. Reported world soil losses from trails ranged from 6.1 Mg ha^-1 y^-1 to 2090 Mg ha^-1 y^-1, all of which are not sustainable. Trail erosion has mainly been investigated in the USA and is a new topic in other regions of the world. There is a need to implement mitigation measures to avoid land degradation, and this should be researched in the near future as right now most of the research describes and quantifies the problem but does not provide solutions: mitigation, rehabilitation or restoration. From a pure scientific approach, we claim that there is a need to research the connectivity of flows and the role of the trails on runoff generation and then sediment yield at pedon, slope and watershed scales. There is a need to research the mechanisms of the soil erosion process in trails: trampling effect, wheel impact, factors and seasonal and temporal changes.

The influence of layout on Appalachian Trail soil loss, widening, and muddiness: Implications for sustainable trail design and management

This research investigates the influence of layout and design on the severity of trail degradation. Previous trail studies have been restricted by relatively small study areas which provide a limited range of environmental conditions and therefore produce findings with limited applicability; this research improves on this limitation by analyzing a representative sample of the Appalachian Trail with significant topographical, ecological, use-related, and managerial diversity. Many trail science studies have also focused on a singular form of trail degradation, whereas this study investigates all three core types of trail impact: trail soil loss, widening and muddiness. Relational analyses with all three indicators provide a more cohesive understanding of trail impact and reveal interrelationships between trail degradation processes. ANOVA testing of the mean values for these trail impact indicators across categories of influential independent factors confirms and refines the relevance of core trail design principles, specifically the sustainability advantages of trails with low grades and side-hill alignments. Findings also reveal and clarify the importance of landform grade in determining the susceptibility of trails to degradation and the influence of routing decisions; these relationships have received relatively little attention in the literature. The results also reveal several methodological considerations for trail alignment metrics and trail impact indicators.

Does resilience yield dividends? Co-benefits of investing in increased resilience in Cedar Rapids

Cedar Rapids, IA, offers a unique case study in planning for increased resilience. In 2008, Cedar Rapids experienced severe flooding. Rather than simply rebuilding, the city of Cedar Rapids began to invest in a resilient flood control system and in the revitalization of its Downtown neighborhood. This paper develops a Computable General Equilibrium (CGE) model for the regional economy of Cedar Rapids to quantify 'resilience dividends': net co-benefits of investing in increased resilience. A resilience dividend includes benefits to the community even if another disaster does not occur. We build a CGE model of Cedar Rapids at two different time periods: one in 2007, before the flooding, and one in 2015, after the flooding and initial investment in resilience. We show that a positive economic shock to the economy results in larger co-benefits for key economic indicators in 2015 than in 2007. Our approach illustrates how co-benefits are distributed throughout the economy.

Towards a Comprehensive Framework for Climate Change Multi-Risk Assessment in the Mining Industry

Changing climate conditions affect mining operations all over the world, but so far, the mining sector has focused primarily on mitigation actions. Nowadays, there exists increasing recognition of the need for planned adaptation actions. To this end, the development of a practical tool for the assessment of climate change-related risks to support the mining community is deemed necessary. In this study, a comprehensive framework is proposed for climate change multi-risk assessment at the local level customized for the needs of the mining industry. The framework estimates the climate change risks in economic terms by modeling the main activities that a mining company performs, in a probabilistic model, using Bayes’ theorem. The model permits incorporating inherent uncertainty via fuzzy logic and is implemented in two versatile ways: as a discrete Bayesian network or as a conditional linear Gaussian network. This innovative quantitative methodology produces probabilistic outcomes in monetary values estimated either as percentage of annual loss revenue or net loss/gains value. Finally, the proposed framework is the first multi-risk methodology in the mining context that considers all the relevant hazards caused by climate change extreme weather events, which offers a tool for selecting the most cost-effective action among various adaptation strategies.

Soil erosion on the "El Portalet" mountain trails in the Eastern Iberian Peninsula

Leisure activities in natural areas have experienced a large increase in popularity. In Mediterranean ecosystems, research on soil erosion in agriculture and forest fire affected land has been well developed but trail erosion has not been widely studied. In this work we evaluated two trails in the eastern Iberian Peninsula to assess soil erosion rates and provide new data. The study area is located in a semi-arid Mediterranean climate (around 400 mm y^-1) and in limestone terrain with scarce soil development. The average erosion rates were 24.39 Mg ha^-1 y^-1 and 40.40 Mg ha^-1 y^-1 for the "Barranc de la Cova de la Hedra" and "Casa del Racó" study trails, respectively. These are non-sustainable rates due to the shallow soils and slow soil development in Mediterranean ecosystems. We found that the depth at the centre of the trail and the maximum depth measured could quickly and easily assess soil erosion rates in the mountain trails. Measuring the width and depth in the centre of the trail can assess 91% of the total erosion and reduces the time of the survey by 80%.

How Networks of Informal Trails Cause Landscape Level Damage to Vegetation

When visitors are not constrained to remain on formal trails, informal trail networks can develop and damage plant communities in protected areas. These networks can form in areas with low growing vegetation, where formal trails are limited, where there is limited regulation and where vegetation is slow to recover once disturbed. To demonstrate the extent of impacts from unregulated recreational use, we assessed damage to alpine vegetation by hikers and pack animals in the highest protected area in the southern Hemisphere: Aconcagua Park, in the Andes. Within the 237 ha area surveyed in the Horcones Valley, over 19 km of trails were found, nearly all of which (94%) were informal. This network of trails resulted in the direct loss of 11.5 ha of vegetation and extensive fragmentation of alpine meadows (21 fragments) and steppe vegetation (68 fragments). When levels of disturbance off these trails were quantified using rapid visual assessments, 81% of 102 randomly located plots showed evidence of disturbance, with the severity of disturbance greatest close to trails. As a result, vegetation in 90% of the Valley has been damaged by visitor use, nearly all of it from unregulated use. These results highlight the extent to which informal trails and trampling off-trail can cause landscape damage to areas of high conservation value, and hence the importance of better regulation of visitor use. The methodology used for off-trail impact assessment can be easily applied or adapted for other popular protected areas where trampling off-trail is also an issue.