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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Evaluation Of Settlement Sites Beyond The Scope Of Natural Conditions And Hazards By Means Of Gis Based Mcda: Yesilirmak Catchment

Cintimur, Mehmet Bilgekagan 01 June 2010 (has links) (PDF)
Our country is a risky position in terms of natural disasters. In the long run, preferentially settlement areas were selected to ensure maximum benefits in terms of both economic and security aspects, other criteria is not taken account when selection of sites. The main purpose of this study is to examine and compare the properties of settlement location based on natural hazard and environmental constraints to be able to understand the interaction between the settlements and natural conditions at the regional scale of YeSilirmak Basin. A MCDA was set up with 10 different data layers in two data domains (environmental and natural hazards domains), are evaluated. The results of the MCDA scores are then transferred to settlement databases in order to evaluate the number of existing settlements in different environmental and natural hazard related suitability classes. It is found that almost 29% of YeSilirmak catchment is environmentally favorable for settlement, and in coherence with that 41% of all existing settlements are located in this zone, indicating a clear preference among the perception of environmentally better places to be settled in. On the other hand with respect to the natural hazards dataset, the locations of the settlements fail to create any preference, as 73,32% of the area is used by 73,50% of existing settlements, which indicates that the perception of natural hazards are low and do not effect settlement criteria, while the acceptable risk of community is high.
62

Land Degradation Assessment For An Abandoned Coal Mine With Geospatial Information Technologies

Emil, Mustafa Kemal 01 September 2010 (has links) (PDF)
This study proposes an approach for land degradation assessment for an abandoned coal mine by using geospatial information technologies. The land degradation assessment focuses on two major changes: topographical and Land Use and Land Cover (LULC). For this purpose, stereo aerial photos, Worldview-1, Landsat and ASTER images, Terrestrial Laser Scanning (TLS) data, Global Positioning System (GPS) data, and ancillary maps were used for abandoned Ovacik surface coal mine. Volume of excavations and fillings, drainage network deviations, and slope instabilities were the investigated topographical disturbances by comparison of the Digital Elevation Models (DEM) for pre- and post-mining stages. Using aerial photos and Worldview-1 satellite image, LULC maps were prepared based on the same time period. Then areal extent and spatial pattern of the LULC change was calculated and mapped by post classification comparison method. The results of land degradation assessment show that there was a significant topographical disturbance and LULC change in the research area. Particularly, three dump areas with a total volume of 2,334,878 m3 were identified by DEM subtraction. It was found that stream network around the primary dump site shifted towards south with a maximum displacement of 60m. Slope analysis reveals that slopes higher that 60 degrees were mainly observed in excavation area with 81 percent. LULC change study showed that the forest area decreased an amount of 106,485 m2 from 1951 to 2008. However / by means of the forestation efforts in dump sites, an amount of 106,012 m2 forest land was recovered.
63

Τα ελληνικά ενδημικά χλωριδικά στοιχεία του εθνικού πάρκου Χελμού - Βουραϊκού : βάση δεδομένων (χαρτογράφηση με χρήση Γεωγραφικών Συστημάτων Πληροφοριών και συσχετισμός με τους τύπους οικοτόπων της Οδηγίας 92/43/ΕΟΚ)

Μακρή, Δήμητρα 07 July 2015 (has links)
Το εθνικό Πάρκο Χελμού – Βουραϊκού βρίσκεται στη βόρεια Πελοπόννησο, η έκταση του είναι περίπου 544,4 Km2 και περιλαμβάνει τέσσερεις (4) Ειδικές Ζώνες Διατήρησης (Ε.Ζ.Δ.) του δικτύου Natura 2000 και 21 τύπους οικοτόπων, εκ των οποίων, δύο (2) αποτελούν οικότοπους προτεραιότητας της Οδηγίας 92/43/ΕΟΚ. Αρχικά η παρούσα εργασία, καταγράφει τα ελληνικά ενδημικά χλωριδικά στοιχεία του Εθνικού Πάρκου, τα οποία ανέρχονται σε 136 taxa, 33 εκ των οποίων είναι ενδημικά της Πελοποννήσου και από αυτά, τα 6 είναι τοπικά ενδημικά. Στη συνέχεια επιχειρεί την συσχέτιση των ελληνικών ενδημικών taxa με τους τύπους οικοτόπων της Οδηγίας 92/43/ΕΟΚ, σύμφωνα με τη θέση όπου έχει αναφερθεί η παρουσία τους εντός της περιοχής μελέτης, καθώς και με τις Ειδικές Ζώνες Διατήρησης του δικτύου Natura 2000 και τις περιοχές προστασίας του Εθνικού Πάρκου όπως ορίζονται στην ΚΥΑ 40390/01-10-2009. Παράλληλα, γίνεται ανάλυση της υψομετρικής κατανομής των μελετώμενων taxa και διερευνώνται οι φυτογεωγραφικές σχέσεις του Χελμού με τα όρη της Πελοποννήσου και της Στερεάς Ελλάδας και της περιοχής μελέτης με τις υπόλοιπες φυτογεωγραφικές περιοχές της Ελλάδας. Επισημάνονται τα χλωριδικά στοιχεία που κατατάσσονται σε κάποια κατηγορία εξαφάνισης ή βρίσκονται σε καθεστώς προστασίας, ο συνολικός αριθμός των οποίων είναι 54 taxa. Τέλος, δημιουργείται βάση δεδομένων που περιλαμβάνει για κάθε taxon, τις συνώνυμες ονομασίες του, την περιγραφή του βιοτόπου και το εύρος των υψομέτρων στα οποία απαντάται, την εμφάνισή του σε άλλες φυτογεωγραφικές περιοχές, εκτός της Πελοποννήσου, την βιομορφή του, το καθεστώς προστασίας, την κατηγορία επικινδυνότητας εξαφάνισης στην οποία κατατάσσεται, τον οικότοπο, την Ειδική Ζώνη Διατήρησης και την Ζώνη Προστασίας του Εθνικού Πάρκου στην οποία βρίσκεται. Στη βάση δεδομένων περιλαμβάνεται, επίσης, για όσα taxa βρέθηκε σχετική πληροφορία, η γεωγραφική τους θέση στην περιοχή μελέτης καθώς και οι παρατηρήσεις των μελετητών που τα συνέλεξαν σε κάθε θέση συλλογής. / The Chelmos - Vouraikos National Park is located in northern Peloponnese, covers about 544,4 Km2 and includes four (4) Special Areas of Conservation (SAC) of Natura 2000 network and 21 habitat types, of which, two (2) are priority habitats according to Directive 92/43/EEC. Initially, this thesis catalogues the Greek endemic floristic elements of the National Park, which numbers 136 taxa, 33 of them are endemic to the area under study and six local endemics. Furthermore, it attempts to correlate the Greek endemic taxa with the habitat types of Directive 92/43/EEC, the Special Areas of Conservation of Natura 2000 network and the conservation zones of National Park, as defined in Joint Ministerial Decision 40390/01-10-2009. At the same time, it is carried out an analysis of taxa’s altitudinal distribution and the phytogeographical relationships between Chelmos and the mountains of Peloponnese and Central Greece as well as among the study area and other phytogeographical regions of Greece are investigated. The floristcs elements under the threat of extinction or under protection status are highlighted, the number of which is 54 taxa. Finally, a database is contracted, that includes for each taxon, synonyms, habitat description, altitude range, presents in other phytogeographical regions, except for the Peloponnese, life form, protection status, category of extinction risk, habitat type, the Special Areas of Conservation and the conservation zones of National Park, where it has been referred. The database includes, also, when the information exists, the geographical location and the observations of researchers who have collected it within the area under study.
64

Spatial Analysis of Fatal Automobile Crashes in Nashville, TN, 2001-2011

Chen, Yan 01 December 2013 (has links)
With increasing levels of motor vehicle ownership, automobile crashes have become a serious public issue in the U.S. and around the world. Knowing when, where, and how traffic accidents happen is critical in order to ensure road safety and to plan for adequate road infrastructure. There is a rich body of literature pertaining to time-related fatal crashes, most of which focuses on non-spatial factors such as a driver’s visibility at night, drinking and drug use, and road conditions. These studies provide a theoretical basis for understanding the causes of crashes from a non-spatial perspective, and a number of traffic laws and policies consequently have been enacted to minimize the impacts of non-spatial factors. Over the past few years, advances in Geographic Information Systems (GIS) have greatly enhanced our ability to analyze traffic accidents from a spatial perspective. This study aims to fill a void in traffic safety studies by comparing and analyzing the differences in the spatial distribution of fatal crashes based on temporal factors, specifically in three periods: 1) day and night; 2) A.M. rush hours and P.M. rush hours; and 3) weekdays and weekends. With the Nashville Metropolitan Area as the study area, the research utilized a number of spatial point-pattern analysis (SPPA) methods, including planar KDE, planar global auto K function, network global cross K functions, and network local cross K functions. All fatal crashes in the Nashville area were found to be clustered and generally follow the patterns of average daily traffic flow. All time-based subtypes of fatal crashes also were found to be concentrated within the central urban area of Nashville, mostly along major roads, and especially near major road intersections and highway interchanges. No notable spatial differences were detected among the subtypes of fatal crashes when applying network global cross K function. However, with the help of the network local cross K function, some localized spatial differences were identified. Some specific locations of hotspots of nighttime and P.M. rush hour fatal crashes were found not to be at the same locations as those at of daytime and A.M. rush hour fatal crashes, respectively. The approach adopted in this study not only provides a new way to analyze spatial distribution of spatial point events such as fatal crashes, but it also can be applied readily to real-world applications. A good understanding of where these spatial differences are should help various agencies practice effective measures and policies in order to improve road conditions, reduce traffic accidents, and ensure road safety.
65

Proposing a Theoretical GIS Model for Landslides Analysis : The Case of Mount Cameroon

Tambe-Ebot, Mathias Ashu Tako January 2011 (has links)
This study presents a theoretical GIS model to investigate the relative impacts of geomorphic and environmental factors that govern the occurrence of landslides on the slopes of Mount Cameroon and its surrounding areas. The study area is located along the Cameroon Volcanic Line (CVL), a major structural feature that originates from the south Atlantic and continues into the continental landmass. The quite frequent seismic activity, geologic character, humid tropical climate and high human pressure on hill slopes are the major factors behind the occurrence of landslides in Mount Cameroon. This paper, therefore, underscores the necessity of in-depth follow-up studies concerned with landslides prevention and management based on the relevance of sufficient reliable field methods in landform geomorphology and interpretation. As much is yet to be done to acquire data for structural and surface geology, hydrology, geomorphic processes and physiography of Mount Cameroon, it is difficult at this point in time to considerably apply suitable methods using GIS that would enable identifying and delineating the landslide-prone areas. In addition, the application of environmental surface monitoring instruments will not be meaningful without a clear presentation of which areas are a cause for concern (given that the employment of any slope stability monitoring and rehabilitation efforts will be only possible after appropriate problem-area identification has been done). Consequently, based on the writer’s previous work in the Mount Cameroon area and available related literature, a methodology using GIS is proposed, which provides the capability to demonstrate how the impact of individual or collective geomorphologic site-specific factors on landslides occurrence could be justified. Considering that digital data may not be readily available, a procedure for the creation of data and analysis of themes is proposed and illustrated. The factors analysis approach in landslides analysis may be cheaper and easier to employ in Mount Cameroon and similar problem regions in developing countries (given that there may be problems of limited financial resources and available expertise in GIS technology and applications). The study underscores and recommends the necessity for a later practical implementation with the availability of adequate resources.
66

Application of multivariate statistics and Geographic Information Systems (GIS) to map groundwater quality in the Beaufort West area, Western Cape, South Africa

Solomon, Henok Goitom January 2013 (has links)
<p><font face="TimesNewRomanPSMT"> <p align="left">Groundwater in arid and semi-arid areas like the Karoo region of South Africa is an important source of domestic, agricultural and industrial source of fresh water. As a scarce resource, it requires extensive quality control and protection through innovative methods and efficient strategies. The town of Beaufort West and its vicinity use groundwater as a major source of municipal and private water supply. Forty nine groundwater samples were collected from spatially referenced boreholes located in and around the town of Beaufort West and were analyzed for <font face="TimesNewRomanPSMT">EC, pH, <font face="TimesNewRomanPSMT">TDS,<font face="TimesNewRomanPSMT">TH, SAR, TA, Ca</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">2+</font></font><font face="TimesNewRomanPSMT">, Mg</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">2+</font></font><font face="TimesNewRomanPSMT">, Na</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">+</font></font><font face="TimesNewRomanPSMT">, K</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">+</font></font><font face="TimesNewRomanPSMT">, HCO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">3-</font></font><font size="3" face="TimesNewRomanPSMT">, Cl</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">-</font></font><font size="3" face="TimesNewRomanPSMT">, NO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">3- </font></font><font size="3" face="TimesNewRomanPSMT">and SO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">42- </font></font><font face="TimesNewRomanPSMT"><font size="3">according to&nbsp / <font face="TimesNewRomanPSMT">SANS 241 standards and tested for ionic balance. The groundwater of the study area was characterized using WHO and South African drinking water quality standards as well as TDS and Salinity hazard classifications. These comparisons and classifications characterized the groundwater of the study area as hard to very hard, with low to medium salinity hazard. These results are in accordance with the dominance of the ions Ca</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">2+</font></font><font face="TimesNewRomanPSMT">, Na</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">+</font></font><font face="TimesNewRomanPSMT">, HCO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">3 - </font></font><font face="TimesNewRomanPSMT">and Cl</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">- </font></font><font face="TimesNewRomanPSMT">in the groundwater samples. Linear relationships between the hydrochemical variables were analysed through correlation and multiple regression analysis to relate the groundwater quality to the underlying hydrogeochemical processes. These linear relationships explained the contribution of the measured variables towards the salinity, hardness and anthropogenic contamination of the groundwater. The groundwater of the study area was also assessed using conventional trilinear diagrams and scatter plots to interpret the water quality and determine the major ion chemistry. The conventional methods highlighted the sources of the hydrochemical variables through analysis and interpretation of rock-water interaction and evaporations processes. To supplement <font face="TimesNewRomanPSMT">these conventional methods and reveal hidden hydrogeochemical phenomenon, multivariate statistical analyses were employed. Factor analysis reduced the hydrochemical variables into three factors (Hardness, Alkalinity and Landuse) that characterize the groundwater quality in relation to the source of its hydrochemistry. Furthermore, combination of Cluster (CA) and Discriminant analyses (DA) were used to classify the groundwater in to different hydrochemical facies and determine the dominant hydrochemical variables that characterize these facies. The classification results were also compared with the trilinear diagrammatic interpretations to highlight the advantages of these multivariate statistical methods. The CA and DA classifications resulted in to six different hydrochemical facies that are characterized by NO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">3 -</font></font><font face="TimesNewRomanPSMT">, Na</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">+ </font></font><font face="TimesNewRomanPSMT">and pH. These three hydrochemical variables explain 93.9% of the differences between the water types and highlight the influence of natural hydrogeochemical and anthropogenic processes on the groundwater quality. All the univariate, bivariate, multivariate statistical and conventional hydrogeochemical analyses results were analyzed spatially using ArcGIS 10.0. The spatial analysis employed the Inverse Distance Weighted (IDW) interpolation method to predict spatial distribution of unmeasured areas and reclassification of the interpolation results for classification purposes. The results of the different analyses methods employed in the thesis illustrate that the groundwater in the study area is generally hard but permissible in the absence of better alternative water source and useful for irrigation.</font></font></font></font></font></font></p> </font></p>
67

Application of multivariate statistics and Geographic Information Systems (GIS) to map groundwater quality in the Beaufort West area, Western Cape, South Africa

Solomon, Henok Goitom January 2013 (has links)
<p><font face="TimesNewRomanPSMT"> <p align="left">Groundwater in arid and semi-arid areas like the Karoo region of South Africa is an important source of domestic, agricultural and industrial source of fresh water. As a scarce resource, it requires extensive quality control and protection through innovative methods and efficient strategies. The town of Beaufort West and its vicinity use groundwater as a major source of municipal and private water supply. Forty nine groundwater samples were collected from spatially referenced boreholes located in and around the town of Beaufort West and were analyzed for <font face="TimesNewRomanPSMT">EC, pH, <font face="TimesNewRomanPSMT">TDS,<font face="TimesNewRomanPSMT">TH, SAR, TA, Ca</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">2+</font></font><font face="TimesNewRomanPSMT">, Mg</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">2+</font></font><font face="TimesNewRomanPSMT">, Na</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">+</font></font><font face="TimesNewRomanPSMT">, K</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">+</font></font><font face="TimesNewRomanPSMT">, HCO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">3-</font></font><font size="3" face="TimesNewRomanPSMT">, Cl</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">-</font></font><font size="3" face="TimesNewRomanPSMT">, NO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">3- </font></font><font size="3" face="TimesNewRomanPSMT">and SO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">42- </font></font><font face="TimesNewRomanPSMT"><font size="3">according to&nbsp / <font face="TimesNewRomanPSMT">SANS 241 standards and tested for ionic balance. The groundwater of the study area was characterized using WHO and South African drinking water quality standards as well as TDS and Salinity hazard classifications. These comparisons and classifications characterized the groundwater of the study area as hard to very hard, with low to medium salinity hazard. These results are in accordance with the dominance of the ions Ca</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">2+</font></font><font face="TimesNewRomanPSMT">, Na</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">+</font></font><font face="TimesNewRomanPSMT">, HCO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">3 - </font></font><font face="TimesNewRomanPSMT">and Cl</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">- </font></font><font face="TimesNewRomanPSMT">in the groundwater samples. Linear relationships between the hydrochemical variables were analysed through correlation and multiple regression analysis to relate the groundwater quality to the underlying hydrogeochemical processes. These linear relationships explained the contribution of the measured variables towards the salinity, hardness and anthropogenic contamination of the groundwater. The groundwater of the study area was also assessed using conventional trilinear diagrams and scatter plots to interpret the water quality and determine the major ion chemistry. The conventional methods highlighted the sources of the hydrochemical variables through analysis and interpretation of rock-water interaction and evaporations processes. To supplement <font face="TimesNewRomanPSMT">these conventional methods and reveal hidden hydrogeochemical phenomenon, multivariate statistical analyses were employed. Factor analysis reduced the hydrochemical variables into three factors (Hardness, Alkalinity and Landuse) that characterize the groundwater quality in relation to the source of its hydrochemistry. Furthermore, combination of Cluster (CA) and Discriminant analyses (DA) were used to classify the groundwater in to different hydrochemical facies and determine the dominant hydrochemical variables that characterize these facies. The classification results were also compared with the trilinear diagrammatic interpretations to highlight the advantages of these multivariate statistical methods. The CA and DA classifications resulted in to six different hydrochemical facies that are characterized by NO</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">3 -</font></font><font face="TimesNewRomanPSMT">, Na</font><font size="1" face="TimesNewRomanPSMT"><font size="1" face="TimesNewRomanPSMT">+ </font></font><font face="TimesNewRomanPSMT">and pH. These three hydrochemical variables explain 93.9% of the differences between the water types and highlight the influence of natural hydrogeochemical and anthropogenic processes on the groundwater quality. All the univariate, bivariate, multivariate statistical and conventional hydrogeochemical analyses results were analyzed spatially using ArcGIS 10.0. The spatial analysis employed the Inverse Distance Weighted (IDW) interpolation method to predict spatial distribution of unmeasured areas and reclassification of the interpolation results for classification purposes. The results of the different analyses methods employed in the thesis illustrate that the groundwater in the study area is generally hard but permissible in the absence of better alternative water source and useful for irrigation.</font></font></font></font></font></font></p> </font></p>
68

Habitat fragmentation and the southern brown bandicoot Isoodon obesulus at multiple spatial scales

Paull, David James, Physical, Environmental & Mathematical Sciences, Australian Defence Force Academy, UNSW January 2003 (has links)
This thesis investigates the process of habitat fragmentation and the spatial and temporal scales at which it occurs. Fragmentation has become an important topic in biogeography and conservation biology because of the impacts it has upon species??? distributions and biodiversity. Various definitions of fragmentation are available but in this research it is considered to be the disruption of continuity, either natural or human-induced in its origins and operative at multiple spatial scales. Using the distribution of the southern brown bandicoot Isoodon obesulus as a case study, three spatial scales of fragmentation were analysed. At the continental scale, the Australian distribution of the subspecies I. o. obesulus was examined in relation to climate, geology and vegetation cover at the time of European settlement of Australia and two centuries later. Using archived wildlife records and Geographic Information Systems (GIS) analyses, habitat suitability models were created to assess natural and human-induced fragmentation of the distribution of I. obesulus in 1788 and 1988. At the regional scale, a study was made of the distribution of I. obesulus in the south-east of the State of South Australia. Again, natural and human-induced patterns of habitat fragmentation were modelled using GIS with climate, soil and vegetation data for the time of European settlement and at present. At the local scale, the distribution of I. obesulus was the subject of a detailed field survey of 372 sites within 29 remnant patches of native vegetation in south-eastern South Australia in order to understand the variables that cause habitat fragmentation. Geographic information systems were used again but in a different way to carefully stratify the field survey by overlaying maps of topography, vegetation and past fires. The large dataset collected from the surveys was described using six generalized linear models which identified the significant variables that fragment the distribution of I. obesulus at a local scale. From the results of the field surveys, a subset of four remnants was chosen for further GIS spatial modelling of the probability of I. obesulus occurring within remnants in response to fire via a controlled burning programme put in place to reduce accumulating fuel loads. These investigations show that habitat fragmentation can be caused by different factors at different spatial scales. At the continental scale, it was found that climate played a dominant role in influencing the fragmented distribution of I. obesulus but vegetation change during the past two centuries has also had a profound impact on the availability of habitat. Within south-eastern South Australia, the species??? regional scale distribution is constrained by climate and also by soil and vegetation patterns. Dramatic change to its regional distribution occurred in the 20th century as a result of the clearance of native vegetation for planting pastures, crops and pines. Fragmentation at the regional scale has resulted in the remaining habitat being reduced to small, isolated, remnant patches of native vegetation. At the local scale it was found that variables which disrupt the continuity of I. obesulus habitat within remnants include vegetation cover in the 0-1 m stratum, abundance of Xanthorrhoea australis and soil texture. For a subset of sites located in one landsystem of the study area, named Young, the age of vegetation since it was last burnt was also found to be a significant variable, with vegetation 10-14 years old since burning providing the most suitable habitat. Spatial modelling of two scenarios for prescribed burning over 15 years revealed that the use of fire as a habitat enhancement tool will be complicated and require a detailed understanding of the factors that cause natural fragmentation in the distribution of I. obesulus at the local scale. A further conclusion of the study was that ecological relationships between species and their habitats require careful interpretation of multi-scaled datasets and conservation plans for endangered species ought to be made at multiple spatial scales. Future research directions are identified including the linking of multi-scaled habitat fragmentation models to genetic studies of the species throughout its range.
69

Conjunto de procedimentos de engenharia reversa para projeto de banco de dados espaciais / Set of reverse engineering procedures for spatial database design

Matté, Lia Cláudia January 2002 (has links)
Projetos de SIG (Sistemas de Informação Geográfica), em geral, ainda não apresentam modelo conceitual de banco de dados geográficos. Os implementadores de SIG se preocupam com a aquisição dos dados (captura e adaptação), que é a etapa mais cara, e dão, ainda, pouca atenção à modelagem. A utilização de modelos conceituais faz com que os usuários controlem melhor sua base de dados e tirem maior proveito do SIG. O objetivo deste trabalho é definir um conjunto de procedimentos de engenharia reversa de bancos de dados espaciais que auxiliem na criação e manutenção de modelos conceituais para aplicações de SIG a partir de dados já existentes. Estes procedimentos podem contribuir para um aumento na qualidade dos SIG implementados, auxiliando na popularização da prática de modelagem conceitual de banco de dados geográficos. São estudados três formatos de transferência utilizados por usuários de SIG. A partir daí, é proposto uma arquitetura de sistema de engenharia reversa para SIG. / Even with the increasing use of Geographic Information Systems (GIS), conceptual modeling of geographic databases (GDB) is not yet usual among GIS professionals. This fact can in part be explained by the professional profile of most GIS designers. They usually are more familiar with specific GIS applications than with database technology. Among them, one can find cartographers, geographers, agricultural engineers, and architects. Besides that, the cost of geographic data acquisition is so high that much important is given to acquisition plans during GIS design and less interest is given to the database design process. Especially first time designers do not perceive the importance of a database schema that is independent of a specific GIS product. Conceptual design preserves the independence between data types and the logical schema of the product. Moreover, relying on the GDB conceptual schema users can better understand what part of the geographic reality is represented in the database. The main goal of this research work is to define a set of reverse engineering procedures for spatial databases that can support either creation or evolution if conceptual GDB schemas. It is expected that these procedures can enhance the quality of GDB design as well as contribute to the popularization of GDB conceptual modeling. Three different geographic data input formats to GIS are investigated and a reverse engineering system architecture for them is proposed. Resulting conceptual (sub)schemas are based on the framework GeoFrame.
70

Análise de Fragilidade Ambiental com Métodos Multicritério - críticas e proposta metodológica / Environmental Fragility Analysis with Multi-Criteria Methods Critiques and Methodological Proposal.

Cereda Junior, Abimael 28 February 2011 (has links)
Made available in DSpace on 2016-06-02T19:58:04Z (GMT). No. of bitstreams: 1 3680.pdf: 16080826 bytes, checksum: 4f465d2a571be2bfd8abfcf8c4083e93 (MD5) Previous issue date: 2011-02-28 / Universidade Federal de Minas Gerais / The attempt to understand the environment through techniques for posterior modifications and interventions is a fact that, for some researchers, made man, human. The understanding on which surrounds a group of individuals can lead, however, to a deterministic reading or even to a superposition, lacking criteria, of the elements in consideration, which leads to distortions in understanding the complex system called environment. Therefore, it s not enough that the gathering of data, and its simple overlap exists, and for spatial data, the accumulation of maps. There is the need of, technical, social and economical criteria to improve understanding, as well as a conceptual-methodological discussion regarding the representation of the Geographical Space. Throughout methodological theories and orientations, such grasp can be achieved by the understanding of, not only one component, but the integration of all components, like in Synthesis Cartography. So, the methods are necessary for the reorganization, transforming data in information (and information onto knowledge), allowing that managers and population can think, analyze and act onto the Space they are inserted in. Thereunto, the multi-criteria methods allows breaking with the statistical representations of the environment, overcoming the inventory paradigm, been that one of the purposes of the present theses, from assumptions of the Environmental Fragility and the utilization of multi-criteria methods of Weighted Linear Combination and Ordered Weighted Averaging, which generates the Map of Environmental Fragility for part of the watershed of Monjolinho River in São Carlos - SP, anchored on the Eco-dynamical approach. Likewise, besides the cartographical product which can subsidize actions from the public power, it was possible the verification of hypotheses that the introduction of one of these methods, from its correct understanding and articulation, allows it to step up to the main purpose of Synthesis Cartography and Planning, be it urban or environmental: the re-integration of variables that concretize territorially in a unison an non-isolated manner, which throughout the Ordered Weighted Averaging method can lead to the transfer of collective technical intelligence, to a Geographic Information System. / A tentativa de apre(e)nder o território por técnicas, para posterior modificação e intervenção, é um fato que, para alguns pesquisadores, tornaram o homem humano. O entendimento do que cerca um grupo de indivíduos pode levar, no entanto, a uma leitura determinista ou mesmo uma sobreposição sem critério dos elementos considerados, o que leva a distorções no entendimento do complexo sistema dito ambiental. Assim, não basta que haja coleta de dados e sua simples superposição, e para dados espaciais, o acúmulo de mapas: são necessários critérios técnicos, sociais e econômicos, bem como a discussão conceitual-metodológica sobre a representação do Espaço Geográfico. Por meio de teorias e orientações metodológicas, tal apreensão pode se dar não somente apropriando-se das partes componentes do sistema, mas sim da integração entre eles, como na Cartografia de Síntese. Desta forma, métodos são necessários para a reorganização deste, transformando dados em informações (e estas em conhecimento), permitindo que gestores e população possam pensar, analisar e agir no seu Espaço. Para isso, os métodos multicritérios possibilitam romper com as representações estáticas do meio, superando o paradigma de inventário, sendo este um dos objetivos da presente tese, a partir dos pressupostos da Fragilidade Ambiental e da utilização dos métodos multicritério da Combinação Linear Ponderada e da Média Ponderada Ordenada, o que gera o Mapa de Fragilidade Ambiental para parte da Bacia do Rio Monjolinho, em São Carlos SP, ancorados na abordagem Ecodinâmica. Desta forma, além do produto cartográfico que pode subsidiar ações do poder público, foi possível a comprovação da hipótese de que adoção de um destes métodos, a partir do seu arcabouço teórico e articulação metodológica, possibilita caminhar rumo ao principal objetivo da Cartografia de Síntese e também do Planejamento, seja o urbano ou ambiental: a reintegração de variáveis que se concretizam territorialmente de maneira una e não isolada, podendo com o uso do método da Média Ponderada Ordenada haver a transferência da inteligência coletiva técnica e social para um Sistema de Informações Geográficas.

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