Multitemporal dendrogeomorphological analysis of slope instability in Upper Orcia Valley (Southern Tuscany, Italy)

The Upper Orcia Valley (Southern Tuscany, Italy) is a key site for the comprehension of denudation processes typically acting in Mediterranean badlands (calanchi) areas, thanks to the availability of long-lasting erosion monitoring datasets and the rapidity of erosion processes development. These features make the area suitable as an open air laboratory for the study of badlands dynamic and changes in geoheritage due to erosion (i.e. active geomorphosites). Decadal multitemporal investigations on the erosion rates and the geomorphological dynamics of the study area allowed to highlight a decrease in the average water erosion rates during the last 60 years. More in detail, a reduction of bare land and, consequently, of erosion processes effectiveness and a contemporary increasing frequency of mass wasting events were recorded. These trends can be partly related to the land cover changes occurred in the study area from the 1950s onwards, which consist of the significant increase of reforestation practices and important other forms of human impacts on slopes, mainly land levelling for agricultural exploitation. In order to better identify the most significant phases of geomorphological instability occurred in this area during the last decades, an integrated approach based on multitemporal geomorphological mapping and dendrogeomorphology analysis on specimen of Pinus nigra Arn. was used. In detail, trees colonizing a denudation slope located in the surrounding of the Radicofani town (Tuscany, Italy) and characterized by calanchi and shallow mass movements deposits, were analyzed for the 1985-2012 time period. The analysis of the growth anomaly indexes and of compression wood allowed to determine a spatio-temporal differentiation along the slope and respect to an undisturbed reference site. The negative anomaly index results to be more pronounced in the trees located on the investigated slope with respect to the ones sampled in a non-disturbed area. Compression wood characterizes trees on slope sectors mainly affected by runoff and/or mass movements with a different persistence. Erosion rates were finally calculated through dendrogeomorphological analysis on tree roots exposure (0.31-3 cm/y runoff prevailing; 5.86-27.5 cm/y, mass movements prevailing). Dendrogeomorphological results are in accordance with those obtained in the investigated areas with multitemporal photogrammetric and geomorphologic analyses

Assessment and selection of geomorphosites and trails in the Miage Glacier Area (Western Italian Alps)

Glacial environments are considered geomorphosites because they exhibit all of the features that characterise sites of geomorphological interest. The Miage Glacier, in particular, is the most important debris-covered glacier of the Italian Alps, and it has been extensively studied since the 18th century because of its scientific features. In this area, the geomorphological and geological attributes are evaluated at 11 sites that have been individuated along the three main touristic trails, which allow an exploration of the surroundings of the glacial tongue and its two main lobes. Using a methodology previously tested in a fluvial environment, single sites and trails are quantitatively assessed to determine the most suitable trail for educational purposes. Hazards that could potentially affect the trails are considered in terms of both risk education and final selection of the most suitable trails for the various possible user groups. The richness of scientific data in this area should increase its importance as a geomorphosite by increasing the educational value of the Miage Glacier and the Veny Valley

Geoheritage and sport climbing activities : using the Montestrutto cliff (Austroalpine domain, Western Alps) as an example of scientific and educational representativeness

Numerous sites of geological and geomorphological interest (i.e., geosites or geomorphosites) have been recently individuated around the Alps, testifying to the great geodiversity that chara - cterises this mountain range. Some rock cliffs that have been locally equipped as sport climbing sites may also be considered as sites of geological and geomorphological interest: The combination of features such as educational exemplarity and geohistorical importance increase the scientific value of these sites. Progression along climbing routes is intimately connected with the geological and geomorphological features of the cliff; thus, it may be possible to interest typical climbers in the area of the Earth Sciences. A research study was conducted at the Montestrutto climbing wall (Western Alps, Italy), which is located in the Eclogitic Mica - schist Complex of the Austroalpine Domain, with the following objectives: i) to reconstruct the deformation stages at local scales along the sport climbing wall and in the surroundings; ii) to analyse how geological elements are related to the physical elements needed for vertical progression to strengthen the link among geology, morphology and the grade of the routes, and finally iii) to use previous results to evaluate the potential of Montestrutto as a geosite. The detailed study consisted of the quantitative analysis of five routes of varying degrees of difficulty, which produced an interesting relationship among the level of difficulty of the routes and the geological and geomorphological features of the sport climbing wall. The Montestrutto cliff is considered to be a valuable geosite because of the scientific importance (e.g., representativeness, educational exemplarity and geohistorical importance) associated with its high cultural and socio-economic value and high potential for use. Sport climbing in sites such as Montestrutto, which are both scientifically significant and accessible, also in terms of the level of climbing difficulty, could be considered as a possible vehicle for stimulating public interest in the Earth Sciences

Water driven processes and landforms evolution rates in mountain geomorphosites : examples from Swiss Alps

Geomorphic processes driven by water are particularly active in mountain environments, especially under the current climate conditions. Erosion and dissolution processes shape meaningful landforms, in different kinds of deposits and rocks, and in some cases they are classified as geomorphosites. Such landforms, especially earth pyramids and rock pillars, are usually characterized by a high scientific value (e.g., representativeness, ecologic support role) and by additional values (e.g., cultural and aesthetic value) contributing to the local geoheritage. Mountain geomorphosites are growing in importance within scientific community and their morphological evolution can affect the global value of the site itself (e.g., integrity). In this paper, after a first review on the terminology used for classifying landforms modelled by water runoff and on their meaning within the mountain environment, the results of a detailed research performed at two sample sites, included in the Swiss National Inventory of Geosites, are presented. The two study sites are representative respectively of: i) water runoff on glacial deposits shaping earth pyramids (Pyramides d'Euseigne); ii) water dissolution on gypsum rocks, modelling articulate karst landscapes (Pyramides de gypse du Col de la Croix). For each site, landforms evolution was investigated and denudation rates were estimated by means of different methods: iconographic material analysis, quantitative geomorphology and dendrogeomorphology on exposed roots. Despite the long-term, average rates obtained by means of roots exposure for both water runoff on glacial deposits (e.g., 5.8 mm/y) and dissolution on gypsum rocks (5.6 mm/y) are comparable. Moreover, a strict relation between the activity degree of processes, the integrity of the site and the assignment of geomorphosites to a specific category (i.e., active, passive or evolving passive) emerged from the results

Tree rings as ecological indicator of geomorphic activity in geoheritage studies

Mountain areas are characterized by geomorphic processes, especially mass wasting and snow avalanches, which may impact the landscape affecting also the biological component, trees included. If sites colonized by trees are characterized by geomorphic features with a high Global and Scientific Value, including Representativeness of geomorphological processes, Educational Exemplarity, and Integrity, they can be considered geomorphosites. In the framework of assessment of the Scientific Value of geomorphosites, Ecological Support Role is of great importance. Hence, tree rings derived information can be used as indicators to refine the Scientific Value of the sites and also to propose multidisciplinary approaches to understand landscape dynamics. In fact, trees colonizing sites of geomorphological interest are used for detecting past and present events and tree rings may be considered ecological indicators under different points of view. Arboreal vegetation can register growth disturbances in terms of morphological features, at macro- (particular morphologies of trunks) and micro-scale (annual growth rings, stress indicators like compression wood, traumatic resin ducts), becoming a powerful indicator of the geomorphic activity affecting the landscape. In some cases, combined with other techniques like climate data analysis, they may allow refining the often lacunose historical records of geomorphic events impacting different territories. The integrated analysis carried out in the Loana Valley (Sesia Val Grande UNESCO Geopark, Western Italian Alps), considering a selection of geomorphosites affected by mass wasting processes and snow avalanches and located along a touristic trail, allowed to detect which meteorological thresholds favour hydrogeological instability (i.e. overcome of Mean Annual Rainfall of 6\u201310%). Tree rings data coming from the investigated sites provided information on the recurrence of geomorphic activity, allowing filling gaps within the historical archives, by individuating years during which hydrogeological or snow-related events probably occurred and that were missed (i.e. 1986, 1989, 2001, 2007), and adding details on sites for which temporal constraints had not been found before (i.e. Pizzo Stagno Complex System). Finally, investigated sites demonstrated to differently record the history of instability affecting the area and this difference is mirrored in the sites values that are adopted in the framework of geoheritage analysis (Scientific Value, Ecological Support Role and Educational Exemplarity). The proposed multidisciplinary approach, including geomorphology, dendrogeomorphology and climatology, represents, hence, a useful tool in geoheritage valorisation and management strategies

Papia civitas gloriosa: urban geomorphology for a thematic itinerary on geocultural heritage in Pavia (Central Po Plain, N Italy)

The interaction between geomorphological processes and anthropogenic activities produces an impressive association of geomorphological and archaeological heritage in urban contexts. We analyzed the urban geomorphology and the geo- and cultural heritage in the town of Pavia (N Italy). The city is located in a strategic position, on a series of fluvial terraces where the Romans founded a colony, probably in the place of an Iron Age Gaul settlement. In Medieval Times and the Modern Era, Pavia sprawled outside the Roman walls, creating new urban areas and modifying the landscape. Geomorphological and GIS-spatial analyses integrated with anthropic landform surveying, archaeological data and historical cartography were performed. This multi-disciplinary approach allowed an investigation into how urban development was firstly adapted and then superimposed onto fluvial landforms. As a result, a flexible geocultural itinerary is proposed for linking geoheritage with cultural heritage, and for disseminating urban geomorphology key-concepts

Dendrochronological and geomorphological investigations to assess water erosion and mass wasting processes in the Apennines of Southern Tuscany (Italy)

The Tyrrhenian side of the Central Apennines is located in a lively geological context, in which uplift/denudation dynamics played a key role in landscape evolution. Intense water erosion and gravitational processes led to the development of spectacular badlands on the widespread clayey hillslopes. The Crete d'Arbia badlands (as part of the Crete Senesi of Southern Tuscany) represent one of the most beautiful examples of these landforms developed on Pliocene clays. On the other hand, these rapidly evolving landforms endanger the artistic heritage of the area, as with the Monte Oliveto Maggiore Abbey that was constructed on the top of a badland hillslope and confers additional value to the landscape.In the perspective of monitoring and reconstructing some significant phases of the relief evolution of this area an integrated approach has been used, which is based on dendrogeomorphology and geomorphological monitoring techniques. In particular, the correspondence between the data from dendrogeomorphological indicators and the measured denudation rates on badland hillslopes was tested. The sampling for dendrogeomorphological analysis has been performed in two stages on 45 trees of the Pinus pinea L. species, on hillslopes affected by soil creep and shallow landslides, in order to identify annual ring growth anomalies, compression wood and roots exposure. Trees' local behaviour is not homogeneous but some common trends have been detected on the basis of the anomaly index and compression wood. Since 1993 several monitoring stations at badland denudation "hot spots" have been equipped with erosion pins; quantitative data from monitoring stations, compared to pluviometric series, indicated critical phases of denudation that were supported by dendrochronological data. The integrated approach between dendrogeomorphology and geomorphological monitoring techniques allowed calibration of both tools in order to extend the analysis in the period preceding the field measurements. This kind of approach, capable of implementation in many contexts, could be particularly helpful in order to forecast the relief evolutionary trend

Use and misuse of multivariable approaches in interventional cardiology studies on drug-eluting stents: a systematic review.

Aims: Randomized clinical trials (RCTs) are the most reliable evidence, even if they require important resource and logistic efforts. Large, cost-free and real-world datasets may be easily accessed yielding to observational studies, but such analyses often lead to problematic results in the absence of careful methods, especially from a statistic point of view. We aimed to appraise the performance of current multivariable approaches in the estimation of causal treatment and effects in studies focusing on drug-eluting stents (DES). Methods and Results: Pertinent studies published in the literature were searched, selected, abstracted, and appraised for quality and validity features. Six studies with a logistic regression were included, all of them reporting more than 10 events for covariates and different length of follow-up, with an overall low risk of bias. Most of the 15 studies with a Cox proportional hazard analysis had a different follow-up, with less than 10 events for covariates, yielding an overall low or moderate risk of bias. Sixteen studies with propensity score were included: the most frequent method for variable selection was logistic regression, with underlying differences in follow-up and less than 10 events for covariate in most of them. Most frequently, calibration appraisal was not reported in the studies, on the contrary of discrimination appraisal, which was more frequently performed. In seventeen studies with propensity and matching, the latter was most commonly performed with a nearest neighbor-matching algorithm yet without appraisal in most of the studies of calibration or discrimination. Balance was evaluated in 46% of the studies, being obtained for all variables in 48% of them. Conclusions: Better exploitation and methodological appraisal of multivariable analysis is needed to improve the clinical and research impact and reliability of nonrandomized studies. (J Interven Cardiol 2012;**:1-1