http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. 2013-05-23T18:52:14Z http://hdl.handle.net/2067/75 Title: Sperimentazione di tecniche per l'analisi multilivello della diversità strutturale di soprassuoli forestali Authors: Lamonaca, Andrea Abstract: Negli ecosistemi forestali la biodiversità è alla base della stabilità ecologica e della complessità dell'ecosistema stesso. La conservazione della biodiversità è dunque fondamentale per il mantenimento dell'integrità degli ecosistemi, per il funzionamento dei processi evolutivi che interessano l'ecosistema e per consentire, entro certi limiti, di cicatrizzare i disturbi di natura antropica prodotti all'interno degli ecosistemi forestali. La diversità strutturale di soprassuoli forestali a scala di popolamento (α-diversità) viene generalmente descritta in funzione dei principali caratteri somatici che ne descrivono la struttura. L'utilizzo del telerilevamento nell'ambito dell'α-diversità è tuttavia ancora poco noto, soprattutto perché in passato la risoluzione geometrica delle immagini prodotte non consentiva una sua applicazione a scala di dettaglio. L'analisi multilivello della diversità strutturale si pone come modello di studio che utilizza congiuntamente le informazioni derivanti dall'eterogeneità geometrica e spettrale e dall'eterogeneità strutturale, che caratterizzano i boschi a livello di popolamento e di paesaggio. La quantificazione dell'eterogeneità spettrale e geometrica di immagini multispettrali ad alta risoluzione QuickBird tramite un algoritmo di segmentazione multirisoluzione è stata utilizzata per individuare i sottopopolamenti arborei, caratterizzati da una loro diversità strutturale, quantificata a terra tramite la misura di un sistema di indici strutturali basati sulle relazioni tra alberi vicini (neighbourood based structural indices). L'analisi multilivello della diversità strutturale, applicata in una faggeta con caratteristiche vetuste dell'alto Lazio, si pone come strumento innovativo nello studio delle dinamiche evolutive dei popolamenti forestali, a supporto della pianificazione e della gestione selvicolturale e in connessione alle metodologie convenzionali di rilievo assestamentale.; Biodiversity is the base of ecological stability and complexity in the forest ecosystems. Conservation of the biodiversity is fundamental for the integrity of the ecosystems, for the operation of the evolutionary processes that interest the ecosystem and to close the human disturbances produced inside the forest ecosystems. Generally the structural diversity of forest stands (α-diversity) is described by the main somatic characters of the forest stand structure. Use of remote sensing for study α-diversity is little known, because in passed the geometric resolution of the remote sensing images didn't allow analysis of details. Multi-level assessment for structural diversity of forest stands is a model of analysis that jointly uses the informations obtained from geometric and spectral heterogeneity and from the structural heterogeneity, that characterize the conditions of forest stands to level of population and landscape. Quantification of the spectral and geometric heterogeneity of very high resolution remotely sensed images QuickBird has been achieved through an algorithm of multiresolution segmentation. The multiresolution segmentation produces image objects that separate regions, characterized by a set of trees. The structural diversity of trees within every regions is quantified by an integrated set of neighbourhood-based indices, based on the relationships among near trees. Multi-level assessment for structural diversity of forest stands is tested in a beech stand with oldgrowth characteristics in Central Italy. Description: Dottorato di ricerca in Scienze e tecnologie per la gestione forestale e ambientale 2006-02-14T23:00:00Z http://hdl.handle.net/2067/2148 Title: Sviluppo di una procedura innovativa per la cubatura del volume della massa legnosa di fustaie di latifoglie mediante LiDAR Authors: Corona, Piermaria; Chirici, Gherardo; Lamonaca, Andrea; Travaglini, Davide; Mason, Franco; Minari, Emma; Marchetti, Marco; Montaghi, Alessandro Abstract: La tecnica di scansione aerea con strumentazione LiDAR (Light Detection and Ranging) è sempre più presa in considerazione ai fini di analisi e monitoraggio degli attributi dendrometrici dei popolamenti forestali, ma anche per stimare attributi complessi quali il volume della massa legnosa e la biomassa legnosa. Il presente contributo propone una procedura innovativa per la stima del volume di massa legnosa di soprassuoli forestali mediante elaborazione di dati LiDAR in ambiente GIS, in particolare per i popolamenti a prevalenza di latifoglie dove i convenzionali metodi di stima basati sulle misurazioni LiDAR dell’altezza dei singoli fusti arborei conducono in genere a risultati relativamente insoddisfacenti. Description: L'articolo è disponibile sul sito dell'editore http://www.asita.it 2006-12-31T23:00:00Z http://hdl.handle.net/2067/2122 Title: Potenzialità delle immagini telerilevate Spot 5 per inventari forestali su vasta scala. Authors: Davide, Travaglini; Chirici, Gherardo; Corona, Piermaria; Lamonaca, Andrea; Marchetti, Marco Abstract: The current needs of an in-depth knowledge about forest ecosystems requires the support of very detailed information. That is why up to now air-born imagery has been preferred to satellite imagery for forest inventory applications, at least in Italy. The new satellite sensors with high or very high spatial resolution and quite high spectral resolution allow to overcome such a limit and can be considered as suitable data for forest mapping at high and medium scales as well as inventory supports. In such a view, this paper shows the results of an experimental comparison between sampling point photointerpretation by Spot 5 images and by digital orthophotos (grey scale/8 bit), over a 15000-ha-wide study area in Central Italy. Albeit a more enlarged testing is needed for definitive conclusions, the obtained results already prove the significative efficiency of Spot 5 high resolution images for forest inventory application. 2002-12-31T23:00:00Z http://hdl.handle.net/2067/2083 Title: Sperimentazione di tecniche object oriented per la classificazione di uso/copertura del suolo Corine Land Cover da immagini satellitari a media risoluzione Authors: Giuliarelli, Diego; Corona, Piermaria; Lamonaca, Andrea Abstract: This work aims to assess the potential of segmentation and object oriented classification techniques of satellite images with medium spatial resolution, for land use/cover (Corine Land Cover, CLC) mapping. The tested procedures are assessed both in term of thematic accuracy and working time, with reference to a study area of about 4000 km2 in central Italy. The automatic procedure is carried out by segmentation of the pan-sharpened image and by subsequent classification using membership and standard nearest neighbour functions. Results are evaluated by sample circular photoplots taken from digital IT2000 orthophotos coverage. In terms of overall accuracy, object oriented classification achieves better results than conventional on screen interpretation. The classification shows difficulties for the identification of the “mixed” classes of CLC nomenclature system; however, even in these cases the object oriented techniques provide higher producer and user accuracy than on screen interpretation. On the whole, since they are able to produce more objective and more accurate cartographic products at similar costs, the application of the tested automatic techniques seems to be preferred to the conventional on screen interpretation for satellite images with medium spatial resolution. Description: L'articolo è disponibile sul sito dell'editore www.sisef.it 2006-12-31T23:00:00Z http://hdl.handle.net/2067/2123 Title: Analisi multilivello della diversità strutturale di una faggeta con caratteri di vetustà. Authors: Lamonaca, Andrea; Corona, Piermaria Abstract: The analysis of forest structure is a valuable support tool for forest management. Usually, it is investigated through data acquired by field survey. Multispectral remote sensing is now able to provide information from very high resolution satellite sensors and the object oriented segmentation techniques are particularly efficient to exploit such data. In this work the segmentation of a QuickBird image (spatial resolution = 2,8 m) is used to quantify some aspects of the structural diversity of a Fagus sylvatica stand with old-growth characteristics, located in central Italy (northern Latium). We used three different scale levels to analyze the spatial relationships, the species mingling and the size dominance among single trees, by applying a set of neighbourhood-based indexes. Differences among the dbh distributions were highlighted by the absolute discrepancy algorithm and the Kolmogorov-Smirnov test, at each examined scale level. The association between natural regeneration and gap and extended gap sizes was also analyzed. In the examined conditions, the spectral and geometric heterogeneity quantified by very high resolution multispectral QuickBird imagery proved to be an effective support tool for the characterization of forest stand structural diversity. 2006-12-31T23:00:00Z http://hdl.handle.net/2067/2097 Title: L’indice Winkelmass per l’inventariazione a fini assestamentali della diversità strutturale di soprassuoli forestali Authors: Corona, Piermaria; D'Orazio, Pierluigi; Lamonaca, Andrea; Portoghesi, Luigi Abstract: Spatial pattern of tree species, sizes and ages affects functional processes and biodiversity of forest ecosystems. Therefore, it is more and more important that stand structural diversity can be assessed through easy-to-implement methodologies at forest management scale. This paper discusses the application of a recently proposed index (the Winkelmass index) of tree spatial aggregation, based on the measurement of the angles between neighboring stems, to a beech (Fagus sylvatica L.) forest in Northern Latium (Italy). Results shows that the Winkelmass index can be implemented in a simple and fast way according to objective sampling schemes and allows to produce a raster map of tree aggregation pattern in the forest. Under the stand condition in the test area, only four trees at each sample point were sufficient to characterize prevailing stand horizontal structure. Description: L'articolo è disponibile sul sito dell'editore www.sisef.it 2004-12-31T23:00:00Z http://hdl.handle.net/2067/2093 Title: “ProgettoBosco”: un sistema di supporto alle decisioni per la stesura di piani di gestione forestale quale strumento di sussidio all’attività didattica Authors: Bianchi, Massimo; Bovio, Giovanni; Camia, Andrea; Cantiani, Paolo; Ferretti, Fabrizio; Francesetti, Annalisa; Lamonaca, Andrea; Portoghesi, Luigi; Corona, Piermaria Abstract: The Decision Support System called “ProgettoBosco”, build up for preparing sustainable forest management plans, has been tested as an educational tool at the university level in Italy. This software was succesfully tested with the collaboration of 120 students from the Forestry Faculties of Turin and Tuscia (Viterbo). We show here that using this software students were able to organize effectively data, that have been used to compile, in a rather short time (one week), two forest managent plans, having an extension of 250 and 100 ha. Description: L'articolo è disponibile sul sito dell'editore www.sisef.it 2005-12-31T23:00:00Z http://hdl.handle.net/2067/2092 Title: Confronto sperimentale tra superfici a ceduo tagliate a raso osservate mediante immagini satellitari ad alta risoluzione e tagliate riscontrate amministrativamente Authors: Corona, Piermaria; Giuliarelli, Diego; Lamonaca, Andrea; Mattioli, Walter; Tonti, Daniela; Chirici, Gherardo; Marchetti, Marco Abstract: The aim of this work is to test the potential of SPOT5 satellite images for monitoring coppice clearcuts. The clearcuts, delineated by on screen interpretation of the satellite images, are compared with the administrative statistics reported for a sample of 230 administrative units. Administrative statistics result significantly lower than those by satellite images, with an average ratio between clearcut area observed by SPOT5 images within each sample unit and the corresponding administrative statistics equal to 1.45. The underestimation by the administrative data is likely due to the simplified process of authorization of coppice clearcuts as well as the eventual lack of timeliness and/or loss of data that sometimes hinder the information flow from administrative bodies to National Forest Service, that is in charge of feeding the official forest statistics. In the light of the experimentation carried out, an operational procedure by SPOT5 images is proposed for the statistical calibration of administrative data about coppice clearcuts. Description: L'articolo è disponibile sul sito dell'editore www.sisef.it 2006-12-31T23:00:00Z http://hdl.handle.net/2067/2144 Title: Estimation of growing stock of broadleaved forests by airborne laser scanning Authors: Corona, Piermaria; Lamonaca, Andrea; Chirici, Gherardo; Travaglini, Davide; Marchetti, Marco; Minari, Emma; Montaghi, Alessandro Abstract: Airborne laser scanning (ALS) is increasingly being proposed for surveying forest attributes. The objective of this paper is to present a new approach for the estimation of growing stock based on ALS data. The approach is distinctively developed for broadleaved stands where conventional methods for growing stock estimation based on ALS measurements of single tree heights frequently provide poor results. Theoretical background and model-based statistical estimators are reported. 2007-12-31T23:00:00Z http://hdl.handle.net/2067/2113 Title: Surveying black pine plantations in the province of Rieti (Italy) Authors: Lamonaca, Andrea; Calvani, Paolo; Giuliarelli, Diego; Corona, Piermaria Abstract: Durante il secolo scorso furono realizzati molti rimboschimenti di pino nero in ambito appenninico al fine di recuperare terreni degradati. Vari Autori hanno formulato proposte di gestione per la rinaturalizzazione di questi soprassuoli. La loro applicazione comporta però elevati costi di rilievo in sede di analisi. Obiettivo di questa nota è la proposizione di una metodologia di inventario ricognitivo degli attributi di questo tipo di soprassuoli che consenta di ottenere dati sufficientemente attendibili su ampie superfici, a costi relativamente contenuti. A livello sperimentale è stata realizzata la mappatura dei rimboschimenti di pino nero della provincia di Rieti. La tecnica k-NN è stata utilizzata per spazializzare la provvigione legnosa a partire da aree di saggio a terra con l’ausilio di un’immagine telerilevata Landsat 7 ETM+. A scopo esemplificativo, gli aspetti inventariali sono integrati da misure ecologico-paesistiche per la descrizione spaziale dei rimboschimenti mappati.; In the last century large afforestation programs were carried out in the Apennines to recover degraded lands, mainly by Pinus nigra plantations. Currently, many Authors have proposed management guidelines to foster the naturalization of such woodlands. However, such an option requires the availability of detailed surveys. The aim of this note is to propose a survey protocol for qualifying the landscape pattern of pine reafforestations and for mapping their growing stock on the basis of the k-Nearest Neighbor (k-NN) techniques. A case study application by Landsat 7 ETM+ imagery is here reported concerning the Pinus nigra plantations in the province of Rieti (Central Italy). 2007-12-31T23:00:00Z http://hdl.handle.net/2067/2165 Title: Valutazione multicriteriale della suscettività a interventi di rinaturalizzazione dei rimboschimenti di pino nero e dei soprassuoli di cerro in Toscana Authors: Barbati, Anna; Lamonaca, Andrea; Melini, Davide; Nocentini, Susanna; Corona, Piermaria Abstract: La rinaturalizzazione è uno degli orientamenti colturali di riferimento della gestione sostenibile di formazioni forestali semplificate nella composizione e nella struttura. La pianificazione degli interventi su area vasta può essere utilmente supportata da informazioni georeferenziate sulle condizioni di suscettività alla rinaturalizzazione dei complessi boscati. Nel presente lavoro si applica un approccio multicriteriale alla mappatura della suscettività a interventi di rinaturalizzazione dei rimboschimenti di pino nero (Pinus nigra Arn.) e soprassuoli di cerro (Quercus cerris L.) presenti in Toscana. La valutazione è basata su un approccio fuzzy, mediante costruzione di funzioni di appartenenza in grado di esprimere il variare delle condizioni di suscettività in rapporto ai seguenti fattori mappati su base raster: i) efficienza ecobiologica del popolamento forestale, stimata mediante un indice guidato da dati telerilevati, e utilizzata per definire il grado di opportunità colturale dell’intervento; ii) fattori di contesto (grado di adiacenza del soprassuolo con altre tipologie forestali e diversità fisionomica della copertura forestale a scala locale) intesi come fattori in grado di rafforzare (o depotenziare) l’opportunità colturale dell’intervento; iii) accessibilità e dimensione del soprassuolo, condizionanti la fattibilità operativa dell’intervento. I valori fuzzy dei singoli fattori sono combinati mediante una funzione moltiplicativa in un indice sintetico di suscettività, per individuare a scala vasta ambiti territoriali a cui accordare priorità di intervento. Su scala comprensoriale o aziendale, la disponibilità di indicatori più puntuali può permettere di collegare in maniera coerente gli indirizzi della pianificazione di area vasta alla concreta programmazione degli interventi. 2007-12-31T23:00:00Z http://hdl.handle.net/2067/2117 Title: Post fire natural regeneration monitoring with the integrated use of high resolution remotely sensed images: the case study of the Pineta di Castel Fusano Authors: Chirici, Gherardo; Balsi, Marco; Bertini, Roberta; Bonora, Nico; Chiavetta, Ugo; Ottaviano, Marco; Corona, Piermaria; Lamonaca, Andrea; Giuliarelli, Diego; Mastronardi, Alessandro; Nardinocchi, Giovanni; Sambucini, Valter; Tonti, Daniela; Marchetti, Marco Abstract: La pineta di Castel Fusano (Roma) è stata colpita il 4 luglio del 2000 da un importante incendio boschivo in seguito al quale si è avviata nell’area una intensa rinnovazione naturale sia per via gamica che agamica. Ai fini di monitoraggio della suddetta rinnovazione sono stati realizzati una serie di rilievi a terra in aree campione nel 2003 e nel 2006. Negli stessi anni è stata acquisita la copertura di immagini telerilevate multispettrali ad altissima risoluzione Ikonos e Quick Bird. Scopo del presente lavoro è la sperimentazione di diverse metodologie finalizzate alla modellizzazione delle relazioni esistenti tra i dati telerilevati acquisiti e le misure realizzate a terra per la stima e la mappatura dei fenomeni di rinnovazione gamica e agamica. Sono stati per questo sperimentati metodi sia tradizionali di analisi regressiva multivariata, sia di tipo non parametrico, con algoritmi basati su reti neurali (Relevance Vector Machine e Multi-Layer Perceptron) e k-Nearest Neighbors. Le attività si inquadrano nell’ambito del progetto GRINFOMED - MEDIFIRE per il quale è stato realizzato un apposito software denominato Spatial Forest Modeller (SFM) capace di analizzare le relazioni tra variabili telerilevate e misurate a terra e di individuare i modelli predittivi migliori in modo da derivare mappe tematiche delle variabili acquisite mediante campionamento a terra. Il contributo illustra i dati acquisiti, le metodologie di analisi e di modellizzazione e i risultati ottenuti. Viene inoltre illustrato il funzionamento del software SFM.; Stone pine stand of Castel Fusano (Rome) burnt on July the 4th 2000 during a huge wildfire. As a consequence of the fire an intensive natural sexual and asexual regeneration began. In order to monitor such a regeneration field surveys were carried out in 2003 and 2006 in sample plots. Remotely sensed high resolution images from Ikonos and Quick Bird were acquired for the same years. The purpose of this work is to test different methodologies for modeling existing relationships between remotely sensed images and ground collected data in order to estimate and to map both sexual and asexual regeneration. For such a purpose different methodologies were tested: step-wise Muliple Linear Regression, Neural Networks (Relevance-Vector-Machine and the Multi-Layered-Perceptron) and the k-Nearest-Neighbors. These activities were carried out within the framework of the GRINFOMED- MEDIFIRE also developing a specific software named Spatial Forest Modeler (SFM) able to analyze existing relationships between remotely sensed variables and data collected in the field in order to identify the best available models to map and estimate the studied variables acquired on the basis of a field sampling design. The present paper presents data collected in the field, analysis and modeling methods and achieved results. The SFM software is also presented. 2007-12-31T23:00:00Z http://hdl.handle.net/2067/1939 Title: Remote sensing support for post fire forest management Authors: Corona, Piermaria; Lamonaca, Andrea; Chirici, Gherardo Abstract: Monitoring of forest burnt areas has several aims: to locate and estimate the extent of such areas; to assess the damages suffered by the forest stands; to check the ability of the ecosystem to naturally recover after the fire; to support the planning of reclamation interventions; to assess the dynamics (pattern and speed) of the natural recovery; to check the outcome of any eventual restoration intervention. Remote sensing is an important source of information to support all such tasks. In the last decades, the effectiveness of remotely sensed imagery is increasing due to the advancement of tools and techniques, and to the lowering of the costs, in relative terms. For an effective support to post-fire management (burnt scar perimeter mapping, damage severity assessment, post-fire vegetation monitoring), a mapping scale of at least 1:10000-1:20000 is required: hence, the selection of remotely sensed data is restricted to aerial imagery and to satellite imagery characterized by high (HR) and, above all, very high (VHR) spatial resolution. In the last decade, HR and VHR passive (optical) remote sensing has widespread, providing affordable multitemporal and multispectral pictures of the considered phenomena, at different scales (spatial, temporal and spectral resolutions) with reference to the monitoring needs. In the light of such a potential, the integration of GPS field survey and imagery by light aerial vectors or VHR satellite is currently sought as a viable option for the post-fire monitoring. 2007-12-31T23:00:00Z http://hdl.handle.net/2067/2066 Title: Conversion of clearcut beech coppices into high forests with continuous cover: A case study in central Italy Authors: Ciancio, Orazio; Corona, Piermaria; Lamonaca, Andrea; Portoghesi, Luigi; Travaglini, Davide Abstract: Converting coppices into high forests with continuous cover has often been established during the last decades as a management goal in hilly and mountainous Mediterranean areas to attenuate the negative effects that frequent clearcutting may have on soil, landscape and biodiversity conservation. The silvicultural tool usually adopted for this purpose is the gradual thinning of sprouts during the long span of time required to complete the conversion, that also allows the owner to keep harvesting some wood. This research compared the effects of various thinning intensities (three treatments plus control) on the stand growth and structure of a beech coppice with standards. The optimal density after thinning was assessed by expressing mean tree spacing as a function of main stand attributes like stand height and stand dbh. This system was preferred to the empirical evaluation of the percentage of basal area to be removed in order to give forest managers general reference guidelines to adapt to the varying environments of the Mediterranean mountains. Results confirmed that the positive effects of thinning on mean stem volume is due more to the higher diameter increment than to different height growth. The acceleration of crown growth in the thinned plots allowed canopy closure to be achieved 13 years after thinning. This reduced the negative effects of the opening of the stand overlayer and the elimination of most suppressed trees on soil protection. Under the conditions examined, the best thinning intensity proved to be a stand density 20% lower than normal prescribed by the yield tables elaborated for beech high forests in Central and Southern Italy. 2005-12-31T23:00:00Z http://hdl.handle.net/2067/2087 Title: Exploring forest structural complexity by multi-scale segmentation of VHR imagery Authors: Lamonaca, Andrea; Corona, Piermaria; Barbati, Anna Abstract: Forests are complex ecological systems, characterised by multiple-scale structural and dynamical patterns which are not inferable from a system description that spans only a narrow window of resolution; this makes their investigation a difficult task using standard field sampling protocols. We segment a QuickBird image covering a beech forest in an initial stage of old-growthness – showing, accordingly, a good degree of structural complexity – into three segmentation levels. We apply field-based diversity indices of tree size, spacing, species assemblage to quantify structural heterogeneity amongst forest regions delineated by segmentation. The aim of the study is to evaluate, on a statistical basis, the relationships between spectrally delineated image segments and observed spatial heterogeneity in forest structure, including gaps in the outer canopy. Results show that: some 45% of the segments generated at the coarser segmentation scale (level 1) are surrounded by structurally different neighbours; level 2 segments distinguish spatial heterogeneity in forest structure in about 63% of level 1 segments; level 3 image segments detect better canopy gaps, rather than differences in the spatial pattern of the investigated structural indices. Results support also the idea of a mixture of macro and micro structural heterogeneity within the beech forest: large size populations of trees homogeneous for the examined structural indices at the coarser segmentation level, when analysed at a finer scale, are internally heterogeneous; and vice versa. Findings from this study demonstrate that multiresolution segmentation is able to delineate scale-dependent patterns of forest structural heterogeneity, even in an initial stage of old-growth structural differentiation. This tool has therefore a potential to improve the sampling design of field surveys aimed at characterizing forest structural complexity across multiple spatio-temporal scales. Description: L'articolo è disponibile sul sito dell'editore www.sciencedirect.com 2007-12-31T23:00:00Z