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In this paper we analyze upright mountain pine (Pinus montana Miller) radial growth responses to climatic and environmental factors in a valley of the Central Italian Alps. This valley is characterized by intense geomorphological dynamics that can mostly be traced back to instability processes and particularly to debris flows. Here, there are also less active areas that allow undisturbed tree growth and permit dendroclimatic research to be performed. The relationship between climatic factors and radial growth in mountain pine was established by Pearson's correlation and response functions using four chronologies. Two were built using trees located on opposite valley slopes; the other two from the valley bottom. One of these last two is constructed with trees growing in areas occasionally affected by sheetfloods. We found that the climate of the summer months has the strongest influence on tree-ring growth: especially May and July mean temperatures and June precipitation. In contrast, the chronology built with trees located in the valley bottom in an area affected by sheetfloods, shows different climate-growth relationships especially concerning summer precipitation. The burial made by silt layers and the more impermeable conditions of the substrate seem to be the main factors regulating tree growth in this area. Comparing this chronology with the reference chronologies, we found that some years with growth anomalies in the disturbed site correspond to debris flow events dated by previous studies in nearby fans. This paper points out the potential use of mountain pine for dendroclimatic reconstruction and the influence of soft slope processes on tree growth. [ABSTRACT FROM AUTHOR]

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In areas with complex three-dimensional features, slope and aspect interact with light conditions and significantly affect the spatial structure of images acquired by remote sensing instruments (for example, by changing the distribution of shadows and affecting the texture of high resolution imagery). In this scenario, this paper analyses the potential and the effectiveness of an automatic classification system to identify three fundamental vegetation classes (forest, grassland and crops) in the complex topography of the Italian Alps (Autonomous Province of Trento, Italy). This classification system is based on the fusion of spectral information provided by the SPOT-5 multi-spectral channels (Ground Instantaneous Field of View, GIFOV, equal to 10 m) and textural information extracted from airborne digital orthophotos (GIFOV equal to 1 m) and is designed to be user-friendly. The texture of the digital orthophotos was modelled using defined bidirectional variograms, thereby extracting additional information unavailable in first-order texture analyses. Using SPOT-5 multi-spectral information alone, the classification accuracy in the investigated alpine area was equal to 87.5%, but increased to 92.1% when texture information was included. In particular, the texture information significantly increased the classification accuracy for crops (from 68.9% to 87.9%), especially orchards that tend to be classified as lowland deciduous forests, and herbaceous crops (such as maize) that are often misclassified as grasslands. A further simple majority analysis increased the ability of detecting grassland, crops and urban zones. The combination of the majority analysis and the proposed automatic classification system seems an effective approach to classifying vegetation types in highly fragmented and complex Alpine landscapes on a regional scale. [ABSTRACT FROM AUTHOR]

Since 26 September 2005 an Automatic Weather Station (AWSI Forni) has been running on the ablation area of the largest Italian valley glacier, Forni, in the Ortles-Cevedale Group. A 4-year record (from 1 October 2005 to 30 September 2009) of air temperature, relative humidity, wind speed and direction, incoming and outgoing radiative fluxes, air pressure, liquid precipitation, and snow depth is considered. The meteorological data are analyzed to describe glacier surface conditions, to calculate the energy balance, and to evaluate the ice ablation amount. Snow accumulation was measured, thus permitting the estimation of the glacier point mass balance. An annual average amount of melt of -5.4 ± 0.021 m w.e. was calculated and an annual average amount of accumulation of +0.7 ± 0.006 m w.e. was measured at the AWS site. The annual average amount of mass balance was -4.7 ± 0.023 m w.e. Our analyses show that surface conditions during summer and fall seasons are important in regulating glacier albedo and then mass balance. In particular, snow cover presence, due to a longer persistence of spring snow, summer snowfalls and earlier fall solid precipitation, drives the duration of the ice melt period. [ABSTRACT FROM AUTHOR]

This study aimed at estimating the impact of red deer grazing on the productivity of meadows located in Pian Cansiglio, north-eastern Italian Pre-Alps. These meadows (185 ha; average elevation 1000 m asl are managed for hay/silage production (1-2 cuts per season) and are included in a protected area that hosts a high density of deer (around 30 heads/100 ha). In 2008 and 2010, dry matter (DM) production and loss due to deer grazing were estimated with exclusion cages (1 m2; 48 exclusion cages in 2008 and 52 in 2010). Night counts with spotlights were conducted to index deer use of meadows plots. DM production inside the cages was fairly good for the area (first-second cut: 4963-2297 kg DM/ha in 2008, and 4145-2475 kg DM/ha in 2010). DM production outside the cages was significantly lower (first-second cut in 2008: 4199-1378 kg DM/ha, and in 2010: 3376-2052 Kg DM/ha). Therefore, the magnitude of losses was of 15-20% at the first and 25-40% at the second cut. DM losses in the different meadow plots were positively correlated with index of deer use, which in some plots was as high as 7-8 heads/ha. Deer grazing reduced also crude protein (CP) content of forage (15.6±4.4% DM inside exclusion cages and 13.8±3.5% DM outside), with losses being greater where CP content was higher. This study demonstrates that high densities of grazing deer may seriously impact on forage production and quality. [ABSTRACT FROM AUTHOR]

Detailed mapping of the middle Orco Valley in the Western Italian Alps allowed for the reconstruction of the lithostratigraphy and the structural evolution of different tectonic units along a geological section from the Gran Paradiso Massif to the Gneiss Minuti Complex of the Sesia-Lanzo Zone. The studied nappes can be grouped into a Lower Tectonic Element which underwent eclogite facies metamorphism and an Upper Tectonic Element pervasively equilibrated under greenschist facies conditions and lacking evidences of high pressure metamorphism. The mapping of Quaternary deposits, geomorphological features and brittle structural elements provided evidence for the occurrence of a deep-seated gravitational slope deformation on the left side of the middle Orco Valley. [ABSTRACT FROM AUTHOR]

Studying intraspecific spatiotemporal variation in vital rates among populations over a range of environmental conditions is essential to reveal intrinsic and extrinsic factors affecting population dynamics. Mammal populations living at higher elevations often have higher adult survival, shorter breeding seasons, and lower reproductive output per season than at lower elevations. We studied dynamics of a Eurasian red squirrel (Sciurus vulgaris) population in high-elevation, mountain pine (Pinus mugo) forest with extreme winters, in the Central Italian Alps, and compared vital rates with populations in more productive habitats at lower elevations. Average density was 0.14 ± 0.07 squirrels ha-l (range 0.07-0.30 ha-l), and numbers typically increased in summer--autumn as a result of seasonal reproduction and immigration. Mean persistence time was only 12.5 months, and there was a nearly complete population turnover in only two years. Local survival and recruitment rate were correlated with seasonal population growth rate, and partial effect of survival explained 80% of variation in growth rate. While reproductive rate in mountain pine habitat was more similar than in more productive habitats at lower elevations, density and autumn--winter survival were much lower. Thus, red squirrels did not show the adaptations observed in several other mammal species, but might invest heavily in early reproduction to compensate for short life expectancy. [ABSTRACT FROM AUTHOR]

A method for long-term simulation of snow avalanches is developed, based on coupling statistical interpretation of triggering snowfall process and regional avalanche data. The case study area is the Alta Valtellina region, in the northern Italian Alps. Therein, a 21-year-long series of daily snowfall data from 21 snow stations is used to calibrate a daily point snowfall statistical model. Then, a data set including 68 avalanche events from six historical avalanche sites are used to evaluate regionally valid features of avalanche release probability, geometry, and runout. These findings are then used to set up a model for the occurrence of avalanches. One particular case study site is considered, the Vallecetta mountain, of interest because of the considerable number of avalanche events occurring there. Long-term simulation of daily snowfall is performed, which is then fed into a model of snow avalanche occurrence. Snow avalanche simulations are then carried out, resulting in synthetic statistics of avalanche geometry, volume, and runout for a return period of 300 years. These are compared with regionally observed statistics in the considered area, resulting in acceptable agreement. The proposed model allows long-term simulations of avalanche occurrences for evaluation of snow avalanche volume and runout, usable for ecological and geomorphologic purposes. Integration with an avalanche dynamics model would provide long-term avalanche hazard assessment for land use planning purposes. [ABSTRACT FROM AUTHOR]