808 research outputs found
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A comprehensive insight into the geography of forest cover in Italy: Exploring the importance of socioeconomic local contexts
No full textForest cover is a key attribute of local communities and affects the spatial organization of any given region.
Changes in forest cover are influenced by spatially-varying biophysical and anthropogenic factors mainly associated with urban-rural, coastal-inland and elevation gradients. The present study investigates the relationship between the socioeconomic structure of local communities and selected indicators of forest landscape in Italy,
including change in forest area over time (2000−2012), using an exploratory multivariate analysis based on
principal component analysis, hierarchical clustering and discriminant analysis. We assess the importance of socio-spatial structures, economic dynamics and demographic patterns in the geography of forest cover, expansion and loss, considering 149 statistical indicators that are used to evaluate the multiple dimensions of sustainable
development. The results point to agriculture, income, education and labour market indicators as a key predictors of contexts with high forest cover and moderate changes in forest area (both gain and loss) from those with low forest cover and marked changes in forest area. High forest cover in rural districts was spatially associated with local communities featuring depopulation, unemployment, low educational levels and subsistence agriculture. These factors consolidate land abandonment and soil erosion. The highest rate of change in forest
area was observed in economically-growing, accessible local contexts with dynamic socio-demographic profiles. Integrated environmental and socioeconomic policies for sustainable development are required to incorporate forest cover and changes in wooded area as pivotal variables and may benefit from a better understanding of the role of local communities in forest management
An integrated methodological approach to evaluate virtual museums in Real museum contexts
No full text60. NUEVAS REAS PARA EL PTERIDFITO ISOETES DURIEUI BORY (ISOETACEAE) EN LA CUENCA MEDITERRNEA
No full text
Projecting Nonnative Douglas Fir Plantations in Southern Europe with the Forest Vegetation Simulator
No full textIn Italy, Douglas-fir has great potential in terms of wood production and drought tolerance. However, a growth reference for mature stands is lacking. We calibrated
and validated the Pacific Northwest variant of the Forest Vegetation Simulator (FVS) for Douglas-fir plantations in Italy and then ran the calibrated model to test
management alternatives. We calibrated the height-diameter, crown width, crown ratio, and diameter increment submodels of the FVS using multipliers fitted against
tree measurements (n 704) and increment cores (n 180) from 20 plots. Validation was carried out on tree-level variables sampled in 1996 and 2015 in two
independent permanent plots (275 trees). Multiplier calibration improved the error of crown submodels by 7–19%; self-calibration of the diameter growth submodel produced scale factors of 1.0 –5.2 for each site. Validation of 20-year simulations was more satisfactory for tree diameter ( 6% to 1% mean percent error) than for height ( 10% to 8%). Calibration reduced the error, relative to that of yield tables, of the predicted basal area and yield after 50 years. Simulated responses to thinning diverged, depending on site index and competition intensity. The FVS is a viable option for modeling the yield of Douglas-fir plantations in Italy, reflecting the current understanding of forest ecosystem dynamics and how they respond to management interventions
Mapping flood prove areas employing UAV
No full textDottorato di ricerca in Ingegneria dei sistemi agrari e forestaliLa produzione di mappe di allagabilità, che rappresentano il principale strumento non strutturale a livello pianificatorio contro le problematiche del dissesto idrogeologico, segue in genere un approccio tradizionale basato sull’utilizzo della Formula Razionale per la determinazione dell’idrogramma di piena e sulla successiva propagazione di tale idrogramma nel DTM (Digital Terrain Model) attraverso un modello idraulico bidimensionale. Solitamente il modello DTM utilizzato deriva da un rilievo LiDAR (Light Detection and Ranging) oppure da rilevamenti topografici di dettaglio o da cartografie tecniche. In questa sede ci si propone di esplorare una metodologia alternativa e innovativa basata sull’utilizzo di un modello idrologico fisicamente basato (EBA4SUB – Event Based Aproach for Small and Ungauged Basins) per la determinazione dell’idrogramma di piena; successivamente tale idrogramma, alternativo a quello ricavato con la formula razionale, viene veicolato nel DTM utilizzando sempre un modello idraulico bidimensionale per la simulazione idraulico; tuttavia in quest’ultimo caso il DTM è ricavato da un rilievo aereo-fotogrammetrico realizzato con UAV e strumentazione low cost. Obiettivo del presente lavoro è dunque analizzare e quantificare le differenze tra i diversi approcci valutando la misura in cui le variabili comparate, idrologica e morfologica, influenzano le mappe di allagabilità, con lo scopo di proporre una metodologia innovativa combinata per la produzione di tali mappe, sfruttando in particolare i vantaggi del DTM ricavato da UAV, quali in primis economicità, ripetibilità dei risultati e capacità di restituzione dei manufatti antropici.The production of flood prone areas maps, that are the main non-structural instruments against the hydrogeological risk, generally follows a traditional approach based on the use of the Rational Formula for determining the design hydrograph and the subsequent propagation of such hydrograph in the DTM (Digital Terrain model) employing a bi-dimensional hydraulic model. Usually the DTM model used is derived from a survey LiDAR (Light Detection and Ranging) or by a topographic survey or digitizing the official cartography. Here we will explore an alternative and innovative methodology based on the use of a physically based hydrologic model (EBA4SUB - Event Based Approach for Small and Ungauged Basins) for determining the flood hydrograph. Such hydrograph, alternative to that obtained with the rational formula, will be conveyed in the DTM always using a bi-dimensional hydraulic model for the hydraulic simulation. However, in this case, the DTM is derived from a photogrammetric survey employing a UAV and a low cost instrumentation. The aim of this work is therefore to analyze and to quantify the differences between the two aforementioned different approaches evaluating how the input variables, both hydrological and morphological, affect the flooding maps. Moreover, aim of this work is also to propose a combined and innovative methodology for the production of such maps, using the advantages of DTM derived from UAVs, i.e. mainly the low cost, the repeatability and the capacity of reconstruct the man-made structures and buildings
