Protective Function Of Forests Research Articles

Impact of forest type and age on shallow landslide susceptibility: a case study from the 2017 heavy rainfall in northern Kyushu, Japan

ABSTRACT Assessing the impact of forest type and age on shallow landslide susceptibility is important for managing protective functions of forests. Previous studies have examined the correlation between forest types and ages, and shallow landslide susceptibility, but causal effects of forest type and age on shallow landslide susceptibility are yet not clear. This study investigated the causal effect of forest type and age on shallow landslide susceptibility using a propensity score method by combining existing geo-data sets. Here, we focus on shallow landslides caused by an extreme rainfall event on 5–6 July 2017, in the mountainous areas of Asakura City and Toho Village, Fukuoka Prefecture, Japan. Randomly located samples of coniferous forest, broadleaved forest, and young forest exposed to shallow landslide events were analyzed. The inverse probability of treatment weighting with the propensity score was applied to the samples to compare the differences in shallow landslide susceptibility among the three forest classes. Young forest had increased shallow landslide susceptibility, compared with coniferous forest and broadleaved forest, by 3.70 × 10−2 and 4.12 × 10−2, respectively, which corresponded to a two to three times increase in shallow landslide susceptibility when the forest changes from coniferous or broadleaved forest to young forest. No significant difference in shallow landslide susceptibility between coniferous forest and broadleaved forest was observed. These differences in shallow landslide susceptibility should be considered when implementing forest management schemes.

Maintaining the protective function of mountain forests under climate change by the concept of naturalness in tree species composition

In Swiss mountain areas, the protective function of forests is the predominant ecosystem service having high cultural and economic significance. It is assumed that natural forests or close-to-natural forests, i.e., forests being in the equilibrium with environmental conditions are the most resilient and resistant in regard to disturbances and hence best protecting people and assets on the long run. Here, we estimated the naturalness of the tree species composition by comparing Swiss National Forest Inventory (NFI) data with current and future potential Natural forest Site Types (NST). Based on this analysis, we identified species that are under or over-represented in protective mountain forests and derived the subsequent potential for management interventions. The urgency of management interventions is expected be small if all predominant tree species of the idealized potential natural forests are present and only their relative portions in the stand need adjustment. In contrast, interventions are advisable, if predominant tree species of the current and future potential natural forests are absent. Based on NFI data, the tree species composition of 47% of the protective mountain forests were classified as “natural” or “close-to-natural,” while the remaining 53% were classified as “not natural” or “partly natural.” Norway spruce [Picea abies (L.) H. Karst.] and European larch (Larix decidua Mill.) were the two most over-represented species under current and even more so under predicted future climatic conditions. To date, silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) were the two species most frequently absent in protective mountain forests, in which they should prevail. Apart from European beech, the most prominent increase in prevalence is predicted for oak (sessile oak and pubescent oak; Quercus petrea Liebl., Q. pubescens Willd.) and small-leaved lime (Tilia cordata Mill.). These species were currently missing from more than 75% of the stands, in which they are expected to be dominant under future conditions. Our analysis indicates the need to transform tree species compositions of protective mountain forests to optimize fitness under future climates. Some of these transformations will take place naturally, incited by disturbances, others—the majority of them—will need active management interventions.

Presenting a climate-smart forestry evaluation framework based on national forest inventories

Climate-smart forestry (CSF) has gained increasing attention in recent years. Yet, a framework to assess the three pillars of CSF, in terms of mitigation and adaptation to climate change and ecosystem service (ES) provision based on national forest inventory (NFI) data is currently lacking. In this study, we present an assessment framework of CSF based on forest indicators derived from NFI. To quantify the three pillars of CSF we defined 1) mitigation based on the forest carbon stock, 2) adaptation using biodiversity and susceptibility to disturbances caused by storm and bark beetles and 3) ES provision with timber production and protection against avalanches and rockfall. We demonstrate the application of this framework using Swiss NFI data and projections of future forest development under four different management scenarios. Our results show that, in general, the carbon stock is increasing at the national scale when current management practices are maintained. Increases are especially pronounced in the Jura and Southern Alps regions. Trade-offs occur between enhancing mitigation and adaption, and the sustainable provision of ES such as timber production. Scenarios with increased harvesting intensities lead to a higher timber supply in the short-term, while decreasing the carbon stock, biodiversity-related old-growth indicators and the protective function of forests. The indicator framework presented in this study provides a first methodological approach that can support policy making to balance the different forest services in the context of CSF.

Countrywide mapping of shrub forest using multi-sensor data and bias correction techniques

The continual increase of shrub forest in the Swiss Alps over the past few decades impacts biodiversity, forest succession and the protective function of forests. Therefore, up-to-date and area-wide information on its distribution is of great interest. To detect the shrub forest areas for the whole of Switzerland (41,285 km2), we developed an approach that uses Random Forest (RF), bias correction techniques and data from multiple remote sensing sources. Manual aerial orthoimage interpretation of shrub forest areas was conducted in a non-probabilistic way to derive initial training data. The multi-sensor and open access predictor data included digital terrain and vegetation height models obtained from Airborne Laser Scanning (ALS) and stereo-imagery, as well as Synthetic Aperture Radar (SAR) backscatter from Sentinel-1 and multispectral imagery from Sentinel-2. To mitigate the expected bias due to the training data sampling strategy, two techniques using RF probability estimates were tested to improve mapping accuracy. 1) an iterative and semi-automated active learning technique was used to generate further training data and 2) threshold-moving related object growing was applied. Both techniques facilitated the production of a shrub forest map for the whole of Switzerland at a spatial resolution of 10 m. An accuracy assessment was performed using independent data covering 7640 regularly distributed National Forest Inventory (NFI) plots. We observed the influence of the bias correction techniques and found higher accuracies after each performed iteration. The Mean Absolute Error (MAE) for the predicted shrub forest proportion was reduced from 6.04% to 2.68% while achieving a Mean Bias Error (MBE) of close to 0. The present study underscores the potential of combining multi-sensor data with bias correction techniques to provide cost-effective and accurate countrywide detection of shrub forest. Moreover, the map complements currently available NFI plot sample point data.

Оценка эффективности рубок ухода в сухих сосняках Казахского мелкосопочника

According to the current Forest Code of the Republic of Kazakhstan, in the forest plantations of specially protected natural areas, the main forestry measures aimed at the conservation and enhancement of the protective functions of forests are intermediate felling, that is, thinning. Pinus sylvestris L. is one of the main forest-forming species in Kazakhstan. Increasing the stability of forest plantations and the possibility of forming recreationally attractive landscapes through thinning is an urgent problem for plantations growing in arid conditions. The research purpose is to analyze the effectiveness of thinning of high intensity in dry pine forests of the Kazakh Uplands for a 70-year period, using dendrochronological methods. It was proved that in dense pine forests growing in dry conditions, there is an increase in radial growth in each subsequent 10-year period after thinning. It was found with statistical certainty that the greatest response to changes caused by thinning of high intensity was observed between 1949 and 1960. Analysis of indexed tree-ring chronologies using regional curves (indexed average tree-ring chronologies of pine) using a cubic spline function revealed differences in pine radial growth indices from the site where thinning of high intensity were carried out and from the control site (time periods: 1947–1955, 1961–1970, 1981–1990, and 1995–2015). The data obtained show a positive effect of thinning of high intensity on the radial growth of trees in the considered pine forests. In dense pine forests of dry growing conditions of the Kazakh Uplands it is recommended to make 1 or 2 cuttings with thinning intensity of 25–35 % at the age of 20–25 and 40–50, respectively, with subsequent increment thinning.

Role of forests in headwater control with changing environment and society

Forest practices in headwater catchments are related to environmental and social contexts. The aim of this study is to analyse the changing protective functions of forests in the upper plain of the Jizera Mts. (North Bohemia, Czech Republic) since the second half of the 19th century. With time, forests have gradually changed from native stands to spruce plantations (Picea abies), introducing exotic conifers (more resistant to air pollution), and, recently, back to more diverse mixed stands. The priority in protective forest functions there shifted from flood protection to integrated control of water resources (quantity and quality). In the 1980s, forest – water interactions were degraded by consequences of extreme acid atmospheric deposition, forest die-back, and extensive clear-cut. In the Jizerka catchment, first signs of recovery were observed in the early 1990s, but, stream waters there are still affected by prolonged acidification. While reconstruction of stream water chemistry at Jizerka follows the drop of the acid deposition in some 5 years, the revival of stream biota takes 10–15 years. In 2071–2100, the projected climate change shows rising annual air temperatures by 3.0–4.6 °C, decreasing water yield by 65–123 mm, 60% drop in ‘minimum residual discharge’, and 20–30% rise in peak-flows. However, these projected environmental changes cannot substantially decline the high potential in water resource recharge, or, start reverse processes in recent recovery from acidification and radically affect the existence of planned mixed forests in the upper plain of the Jizera Mts.

The influence of climate change and canopy disturbances on landslide susceptibility in headwater catchments

Forests have an important regulating function on water runoff and the occurrence of shallow landslides. Their structure and composition directly influence the risk of hydrogeomorphic processes, like floods with high sediment transport or debris flows. Climate change is substantially altering forest ecosystems, and for Central Europe an increase in natural disturbances from wind and insect outbreaks is expected for the future. How such changes impact the regulating function of forest ecosystems remains unclear. By combining methods from forestry, hydrology and geotechnical engineering we investigated possible effects of changing climate and disturbance regimes on shallow landslides. We simulated forest landscapes in two headwater catchments in the Eastern Alps of Austria under four different future climate scenarios over 200 years. Our results indicate that climate-mediated changes in forest dynamics can substantially alter the protective function of forest ecosystems. Climate change generally increased landslide risk in our simulations. Only when future warming coincided with drying landslide risk decreased relative to historic conditions. In depth analyses showed that an important driver of future landslide risk was the simulated vegetation composition. Trajectories away from flat rooting Norway spruce (Picea abies (L.) Karst.) forests currently dominating the system towards an increasing proportion of tree species with heart and taproot systems, increased root cohesion and reduced the soil volume mobilized in landslides. Natural disturbances generally reduced landslide risk in our simulations, with the positive effect of accelerated tree species change and increasing root cohesion outweighing a potential negative effect of disturbances on the water cycle. We conclude that while the efficacy of green infrastructure such as protective forests could be substantially reduced by climate change, such systems also have a strong inherent ability to adapt to changing conditions. Forest management should foster this adaptive capacity to strengthen the protective function of forests also under changing environmental conditions.

Swot analysis as a prerequisite formation of anti-crisismanagement mechanism of south of Ukraine

The purpose of the article is to carry out a thorough SWOT-analysis of theactivity of the State Enterprise «Mykolaiv Regional Forestry and Hunting Management» as a necessary factor for the formation of a crisis management system of forestry enterprises in the South of Ukraine. The identified potential threatsand inherent weaknesses in the activity of the investigated enterprise require theprompt implementation of an appropriate financial, economic and organizationaltechnical mechanism for the exit of the subject of economic activity from the crisis.Мethodology of the research is to use a set of methods: expert evaluation,comparative and system analysis. This methodological approach made it possibleto analyze the weaknesses and strengths of the activity of the studied enterpriseand to justify the use of a certain strategy on it. The scientific novelty of theobtained results is to investigate the possibility of using separate strategies in theactivities of forestry enterprises in the South of Ukraine. The scientific noveltyof the obtained results is to investigate the possibility of using separate strategiesin the activities of forestry enterprises in the South of Ukraine. The necessity toimplement a strategy aimed at enhancing the ecological and protective function offorest plantations is substantiated. The scientific conclusions drawn on the chosenstrategy determine the necessary directions for the development and implementationof the appropriate mechanism for crisis management of subsidized forestryenterprises. Conclusions. The conducted SWOT-analysis of the activity of the StateEnterprise “Mykolaiv Regional Forestry and Hunting Management” revealed theweaknesses and strengths of the entity, singled out the existing opportunities andpotential threats of the enterprise. The possibility of using a strategy aimed atenhancing the ecological and protective function of forest plantations in theactivities of forestry enterprises in the South of Ukraine has been proved. Thedetermined strategy necessitates further research on the formation of componentsof the respective mechanism of crisis management of forestry enterprises in theSouth of Ukraine.

The effects of forest cover and disturbance on torrential hazards: large-scale evidence from the Eastern Alps

Global human population growth, limited space for settlements and a booming tourism industry have led to a strong increase of human infrastructure in mountain regions. As this infrastructure is highly exposed to natural hazards, a main role of mountain forests is to regulate the environment and reduce hazard probability. However, canopy disturbances are increasing in many parts of the world, potentially threatening the protection function of forests. Yet, large-scale quantitative evidence on the influence of forest cover and disturbance on natural hazards remains scarce to date. Here we quantified the effects of forest cover and disturbance on the probability and frequency of torrential hazards for 10 885 watersheds in the Eastern Alps. Torrential hazard occurrences were derived from a comprehensive database documenting 3768 individual debris flow and flood events between 1986 and 2018. Forest disturbances were mapped from Landsat satellite time series analysis. We found evidence that forests reduce the probability of natural hazards, with a 25 percentage point increase in forest cover decreasing the probability of torrential hazards by 8.7%± 1.2%. Canopy disturbances generally increased the probability of torrential hazard events, with the regular occurrence of large disturbance events being the most detrimental disturbance regime for natural hazards. Disturbances had a bigger effect on debris flows than on flood events, and press disturbances were more detrimental than pulse disturbances. We here present the first large scale quantification of forest cover and disturbance effects on torrential hazards. Our findings highlight that forests constitute important green infrastructure in mountain landscapes, efficiently reducing the probability of natural hazards, but that increasing forest disturbances can weaken the protective function of forests.

Spatial Assessment of Seasonal Changes in Pollution of the Air Ground Layer with Aerosol Particles in School Yards of Tiaret city (Algeria)

According to the data obtained in the autumn-winter period, the excess of PM2.5 in air during the schoolday after a short stay by pupils in the school yards was 1.5 –2 times. The PM2.5 concentration in the autumn - winter period was up to 1.5 times higher than that of the spring – summer time. High concentrations of dust particles are observed in areas close to heavy traffic in winter in the South-Eastern part of the city. Low concentrations were recorded in the autumn-winter time in areas adjacent to forests in the North –Western part of the city of Tiaret. However, the protective function of forest stands in the spring – summer period in the North-Western part of the city of Tiaret is less evident. The need for introduction of several nature protection measures in the city is obvious. Among them: fuel quality control and fines for the use of low-grade fuel, increasing the density of trees and shrubs in the city in the areas uncovered by vegetation.

OPŠTEKORISNE FUNKCIJE ŠUMA U NORMATIVNO-PLANSKIM AKTIMA I U PRAKSI: PRIMJER ŠUMA NA TERITORIJI GRADA BANJALUKE

Ovim radom želimo dati osvrt na problematiku koja se tiče ostvarivanja opštekorisnih funkcija šuma(OKFŠ), kao segmenta savremenog i usvojenog principa višenamjenskog upravljanja šumama. Cilj namje bio da analiziramo važeće normativne i planske akte koji se odnose na problematiku upravljanjašumama sa posebnim osvrtom na: višenamjensko šumarstvo, OKFŠ, zaštitu prirode, da utvrdimo kakose oni u konačnici sprovode u praksi upravljanja šumama, a sve na primjeru šuma na teritoriji GradaBanjaluke. Šume BL smo odabrali jer ih u našim uslovima vidimo kao idelan primjer za realizacijuvišenamjenskog šumarstva, odnosno šume oko samog grada vidimo kao dobar poligon za realizacijuciljeva gazdovanja šumama koji prevazilaze trenutno dominantno zastupljen privredni cilj (moguće jena malom prostoru ostvarivanje seta funkcija), sa posebnim naglaskom na, kako zaštitni, tako i socijalniaspekt OKFŠ (rekreacija, edukacija, povećanje kvaliteta života urbanog stanovništva i sl.). Rezultatiistraživanja ukazuju da postoji solidna osnova unutar normativnih i planskih akata, ali da se na polju realizacijeistih do danas uradilo veoma malo. Na kraju rada su definisane kratke smjernice za poboljšanjestanja u okvirima predmetne problematike.

Natural and antropogenic landscapes as a component of knowledge about environment

The purpose of this article is to discover ways and opportunity to familiarize students with natural and anthropogenic landscapes in the process of studying geography at school. The main material. The article emphasizes the need for geographic education not focusing on the accumulation of little related multilateral knowledge. It reveals the importance of forming a holistic outlook and a comprehensive understanding of nature and the biosphere, as part of nature and environment of human existence. It emphasizes the essential role of knowledge about natural and manmade landscapes, which helps to solve problems of human-nature relationship, giving the possibility to understand natural processes and peculiarities of anthropogenic influence on them. Economic activities in Kharkiv region have led to the formation of various man-made landscapes within the natural landscapes: agricultural, residential, industrial, transport, aquatic, forest. Within the agricultural landscape there is soil degradation, flooding, salinity, erosion, landslides, deflation. In the limits of residential landscapes (urban and rural) relief, microclimate, soils and water objects change, domestic and industrial wastes are formed. Quarries, dumps, road construction, trimming slopes, laying links, piers, reducing the area of forests- all this leads to a negative impact on the composition of soils, groundwater, migration and reproduction of plants and animals. The environment, protective function of forests, biodiversity and the state of the natural landscapes are damaged. Conclusions and further research. Knowledge about anthropogenic transformation of natural landscapes will ensure imagination of the world’s unity, understanding the consequences of negative human influence on the constituent environments, as well as the formation of a responsible approach to cognitive and practical activity of students in the study of geography.

Gravitational natural hazards: Valuing the protective function of Alpine forests

Forests produce significant non-market benefits by protecting residential and commercial real estate as well as all kinds of infrastructure (e.g. rail tracks, highways, power lines) against gravitational natural hazards such as avalanches, mudslides, and rockfall. The Austrian Federal Forests (Österreichische Bundesforste – ÖBf) recently commissioned a research project on the valuation of this ecosystem service by means of the replacement cost method and the hedonic pricing approach.Based on the international literature, this paper focuses on a careful and realistic design of the baseline scenario with which the “marginal change” in ecosystem services can be assessed and valued. While the (current) management scenario is rather clear and reflects the approach pursued by the ÖBf (reasonably labeled as multifunctional forestry), the design of the baseline scenario (intensified commercial forestry) assumes a reduced protective function of the forests which, however, would still have to be in line with strict legal frameworks such as the Austrian Forest Act or European nature conservation directives.Given these strict frameworks, the potential leeway for commercial forestry is rather limited; still, the current multifunctional forest management secures ecosystem services worth up to EUR 14.7m per year (valued at replacement costs of technical measures to substitute the protective function of forests), which corresponds to EUR 268 per hectare and year. The result of the hedonic pricing approach for property in hazard zones protected by forests is substantially lower: The ecosystem service is valued at EUR 2.9m per year (which corresponds to an annual per-hectare value of EUR 53). The results in general underline the importance of multifunctional forestry and of the ecosystem services function sustained especially in state-owned forests.

An overview of maritime pine private non-industrial forest in the centre of Portugal: A 19-year case study

Abstract Portuguese national policies for forests were developed considering related themes such as climate change, forest health, fire and the protective functions of forests. In Portugal, maritime pine forest is mainly private non-industrial and its area is in decline. Therefore, the aim of this study was two-fold: first, to assess maritime pine forest characteristics over a 19-year period; second, to analyse forest cover change over that period. In the end, the implementation of state policies was explored. A study area highly forested by continuous areas of naturally regenerated maritime pine in the centre of Portugal was used. To assess maritime pine forest characteristics, two sets of inventory data collected in previous studies (1991-1996 and 2007-2010) were used. To analyse forest cover change, the official land cover maps for 1990 and 2007 were used. This study findings highlighted that study area’s trends over the past years were the following: first, the decrease of maritime pine forest areas and its management decline (stands less stable, under-stocked, with large amounts of small-diameter poles and enlarged tree size variability); second, the increase of scrubland areas; third, the increase of eucalyptus afforestation with no regard for protection areas; and fourth, the absence of native oaks or introduction of other broadleaves as recommended by the state policies. Therefore, it is argued that there is a need for effective field monitoring actions with regard to the implementation of state policies. Additionally, selective incentives are key to mobilise private non-industrial forest to achieve the goals of state forest policies.

Multifactor empirical mapping of the protective function of forests against landslide occurrence: statistical approaches and a case study

Abstract: Forests are increasingly valued for services beyond timber and non-timber products including land protection with respect to events such as landslides, soil erosion, floods and avalanches. The most important properties of a protective forest are its ecological and mechanical stability. Planning and implementing multifunctional forest management in protective forests is challenging because of the trade-offs and synergies among the many functions of the forest. In this study, a multifactor empirical method is presented for assessing the protective role of forests on a stand scale with respect to landslide occurrence. Multifactor methodologies typically estimate landslide susceptibility exploiting the relationship between past landslide patterns and site characteristics. Two statistical approaches were here applied to assess the probability of landslide occurrence: the weight-of-evidence technique and the logistic regression technique. Statistical analysis was performed on the basis of landslide detachment zone only. The question of how to estimate protective forest function was answered through the comparison of models established with different sets of predicting factors. This study ultimately aims to provide a decision-support tool focused on mapping the potential role of forests in landslide-prone areas. A case study from the Italian Alps was considered. The density of landslide detachment outside forest areas proves to be more than twice than that within forest areas.

Root reinforcement dynamics in subalpine spruce forests following timber harvest: a case study in Canton Schwyz, Switzerland

Root reinforcement is a key factor when dealing with slope stability problems and is an important quantitative criterion for the evaluation of the protective function of forests against shallow landslides, as well as for the adoption of appropriate practices in protection forest management. Although many models have been developed to estimate root reinforcement, a reliable quantification that considers both its spatial and temporal variability still remains a challenge. This work aims to extend the understanding of the long term spatial and temporal dynamics of root reinforcement after forest harvest in subalpine spruce forests by supplying new experimental data and applying a state-of-the-art model.We estimated root reinforcement decay 5, 10 and 15years after timber had been harvested in spruce stands in a small catchment in the Swiss Alps. We collected root distribution data at different distances from the trees and calibrated and validated a root distribution model (RootDis). To estimate root mechanical properties, we tested roots up to 12mm diameter in the field, and computed root reinforcement for each case study with the Root Bundle Model. Finally, we developed a new model for the estimation of root reinforcement decay, based on the observed change in root distribution after felling and on the decay of the root pullout force. The final result is a model for the spatial-temporal prediction of root reinforcement heterogeneity and dynamics in subalpine spruce forest stands. Five year old harvested spruce forest in the climatic conditions of the study area provides 40% of the root reinforcement of live forest, while 15years old harvested forest provides no reinforcement at all. Shrub species and natural regeneration could guarantee almost the 30% of the root reinforcement of a live forest after 15years from cutting. Additional work is now required to further validate the model and implement these results in a slope stability analysis.

Regeneration dynamics and resilience of unmanaged mountain forests in the Northern Limestone Alps following bark beetle-induced spruce dieback

Mountain forests provide many important ecosystem services including protection against avalanche and rock fall. These services often depend on a continuity of forest cover and therefore on ecological stability—resistance and resilience to disturbance. Natural regeneration following large-scale disturbance is an important component of forest resilience but in the mountain forests of the Alps is not well understood. This restricts management decision making, particularly in the face of an increased threat to the currently dominant Norway spruce from the bark beetle (Ips typographus). In light of this, we analyzed bark beetle infestation patterns, forest structure, selected tree regeneration characteristics and species composition on 96 study plots on a chronosequence of bark beetle-induced natural forest succession in unmanaged mountain forest ecosystems in southeastern Germany. The most advanced plots were twenty years on from the bark beetle-induced dieback of mature Norway spruce, and the majority were already quite densely stocked. The regeneration was clustered and was dominated by sycamore maple and Norway spruce. Most notably, the proportion of advance regeneration was negligible with the vast majority of the seedlings having germinated after the disturbance event. The findings suggest that these forests are naturally resilient in terms of regeneration if high browsing intensities do not prohibit the establishment of new seedlings. The bark beetle outbreaks appear to have generated an acceleration of development away from human influenced pure Norway spruce forests toward a more natural species composition. Nevertheless, Norway spruce will remain the dominant species for at least the next generation. These findings are important for managers intending to uphold protective forest functions. The integration of naturally evolving gaps as elements which diversify environmental conditions on the forest stand level as well as on the landscape scale is recommended for close-to-nature forest management.

Assessment of the protective function of forests against debris flows in a gorge of the Slovenian Alps

Protection forests play an important role in mitigating the influence of natural hazards. Despite the growing need for protective functions due to aging forests and increased risk of natural disturbances, active forest management has become increasingly uncommon across the Alps. Active management of protection forests can be facilitated by state subsidies. This requires an objective delineation of forests with a direct protection function and the development of silvicultural techniques that mitigate natural hazards. A study of protection efficiency of beech-dominated forests in the Soteska gorge in NW Slovenia, where a main state road and railway are at risk from debris flows and rockfall, was performed. We assessed the starting points of debris-flow hazard based on a small-scale geological survey of the terrain characteristics and a local debris flow susceptibility map. We applied the TopRunDF model for determination of the run-out zones. Forest structure data were obtained from 26 sample plots. A detailed description and delineation of forest stands was performed. The results showed that these forests play an important role in the protection of infrastructure. Forest protection efficiency can be improved by stand thinning for stability and careful planning of regeneration patches over time and space. In areas where silvicultural measures cannot provide sufficient protection, technical measures are needed. Since these forests have not been managed for several decades, natural disturbances (windthrow) are frequent. Research findings suggest that regular assessment and management of these beech-dominated protection forests are necessary, contrary to the current practice of non-management in protection forests in Slovenia.

Das neue NaiS-Anforderungsprofil Steinschlag

The new NaiS target profile for rockfall Due to new findings on the protective function of forests against rockfall, the Federal Office for the Environment started in 2008 with a revision of the Swiss target profiles for rockfall protection forests. Until now, fall velocity of rocks, rock mass, as well as the forested slope length, were not considered for the determination of the target profile. In order to incorporate all of these important factors, an Internet-based form has been developed which calculates the target profile. This article firstly gives a short overview of the most important aspects of rockfall in protection forests and secondly presents the approach used for the calculation of the new target profile. Although the German word “Steinschlag” only refers to small rock particles, forests also have a protective effect against large blocks (e.g. >5 m3), however, a long forested transit zone with a sufficient number of trees with larger stem diameters is required for a relevant energy and risk reduction. The new target profile offers possibilities to account for such situations as well.

The economic valuation of natural hazards in mountain forests: An approach based on the replacement cost method

Abstract Protection from natural hazards is the most important function of mountain forests from an ecological, economic and social point of view. This assertion has been widely debated in recent years by a number of authors. In this paper we focus on the economic aspects of the protective function of forests, developing a quick and simple estimation method that can be applied on a local scale. We present the results of its application in an Italian Alpine forest. After having identified the main forest attributes directly or indirectly involved in protection, the economic value of the protective function for homogeneous zones was estimated by applying the replacement cost method. This value enables environmental concerns to be included in forest planning and political decision-making.