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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.
51

The importance of fisheries waste in the diet of Westland Petrels (Procellaria westlandica)

Freeman, A. N. D. January 1997 (has links)
Westland petrels Procellaria westlandica breed only near Punakaiki on the West Coast of New Zealand. About 80 km offshore from their breeding colony, New Zealand's largest commercial fishery (for hoki Macruronus novaezelandiae) operates from mid June to early September, coinciding with the Westland petrel's breeding season. It has been assumed that Westland petrels feed extensively on fisheries waste and that this habit has been at least partly responsible for the increase in the Westland petrel population. Some seabird biologists have expressed concern that if a species comes to depend on scavenging at fishing vessels, such a species could experience a food crisis if fishing operations changed in a way that reduced the quantity of waste discharged. The aim of this research was to assess how dependent Westland petrels have become on fisheries waste for food. Diet studies showed that during the hoki fishing season, waste accounts for more than half by weight of the solid food Westland petrels bring back to the colony to feed their chicks. After the hoki season, waste contributes only about a quarter of their diet as birds switch to more natural prey and scavenge a wider variety of fish species presumably from smaller, inshore fishing vessels. Much of the fisheries waste eaten by Westland petrels was flesh which could not be identified using traditional techniques. The electrophoretic technique iso-electric focusing increased the number of fish samples that could be identified and consequently the diet was interpreted differently than it would have been had only traditional diet analysis been used. The survey of Westland petrel distribution off the west coast of the South Island, found that although hoki fishing vessels influence the distribution of Westland petrels, only a small proportion of the Westland petrel population appears to utilise this food resource at any one time. Westland petrels were tracked at sea by VHF radio telemetry and then by satellite tracking. Satellite tracking showed that there is considerable variation in the amount of time Westland petrels spend in the vicinity of fishing vessels. On average, satellite tracked birds spent one third of their time near vessels, but they foraged over much larger areas than that occupied by the West Coast South Island hoki fishing fleet. Although fisheries waste is an important component of the Westland petrel diet, it appears that the situation is one of opportunistic use of a readily available resource, rather than one of dependence. Several features of the Westland petrel's breeding biology and foraging ecology suggest that Westland petrels could compensate for a reduction in waste from the hoki fishery by switching to other sources of waste and increasing their consumption of natural prey. Nevertheless, much remains unanswered concerning the role of fisheries waste in the Westland petrel's diet. In particular, quantifying the waste available to seabirds, and the success of Westland petrels in acquiring that waste compared to other scavenging species, is needed in order to better predict the effect of a reduction in fisheries waste on Westland petrel population size.
52

Wetland planning in agricultural landscape using Geographical Information System : A case study of Lake Ringsjön basin in South Sweden

Olszewska, Dorota Olga January 2005 (has links)
<p>The problem of increasing eutrophication encouraged the Baltic States to implement new measures, which would help to decrease the nutrient load into the Baltic Sea. Constructed wetlands are considered as one of the possible solutions to the problem of nutrient leakage from agricultural areas in Sweden.</p><p>The aim of this study was to identify the best wetland locations in the Lake Ringsjön basin (in southern Sweden, Scania) using Land Score System (LSS) based on Geographic Information System (GIS). The required area of wetland was calculated on the base of average daily discharge in the whole basin. Next, the possible wetland sites were compared with the location of major nitrogen leakage sources (municipalities, and agriculture). The scenario, which came out from the implemented model (the wetland area required for each sub basin in the Lake Ringsjön basin), was compared to the two scenarios investigated by Swedish Meteorological and Hydrological Institute (SMHI), where wetlands covered 0,4 and 2% of the total cropland area in the Lake Ringsjön basin.</p><p>The result shows that the second SMHI’s scenario relates in some sub basins to the required wetland area calculated in my model. However, in some cases the wetland area seems to be underestimated.</p>
53

Multicriteria analysis and GIS application in the selection of sustainable motorway corridor

Belka, Kamila January 2005 (has links)
<p>Effects of functioning transportation infrastructure are receiving more and more environmental and social concern nowadays. Nevertheless, preliminary corridor plans are usually developed on the basis of technical and economic criteria exclusively. By the time of environmental impact assessment (EIA), which succeeds, relocation is practically impossible and only preventative measures can be applied.</p><p>This paper proposes a GIS-based method of delimiting motorway corridor and integrating social, environmental and economic factors into the early stages of planning. Multiple criteria decision making (MCDM) techniques are used to assess all possible alternatives. GIS-held weighted shortest path algorithm enables to locate the corridor. The evaluation criteria are exemplary. They include nature conservation, buildings, forests and agricultural resources, and soils. Resulting evaluation surface is divided into a grid of cells, which are assigned suitability scores derived from all evaluation criteria. Subsequently, a set of adjacent cells connecting two pre-specified points is traced by the least-cost path algorithm. The best alternative has a lowest total value of suitability scores.</p><p>As a result, the proposed motorway corridor is routed from origin to destination. It is afterwards compared with an alternative derived by traditional planning procedures. Concluding remarks are that the location criteria need to be adjusted to meet construction</p><p>requirements as well as analysis process to be automated. Nevertheless, the geographic information system and the embedded shortest path algorithm proved to be well suited for preliminary corridor location analysis. Future research directions are sketched.</p>
54

Using GIS in Solid Waste Management Planning : A case study for Aurangabad, India

Shaikh, Moiz Ahmed January 2006 (has links)
<p>Waste management is a global environmental issue which concerns about a very significant problem in today’s world. There is a considerable amount of disposal of waste without proper segregation which has lead to both economic and environment sufferings. It is still practiced in many cities. There is a tremendous amount of loss in terms of environmental degradation, health hazards and economic descend due to direct disposal of waste. It is better to segregate the waste at the initial stages where it is generated, rather than going for a later option which is inconvenient and expensive. There has to be appropriate planning for proper waste management by means of analysis of the waste situation of the area.</p><p>This paper would deal with, how Geographical Information System can be used as a decision support tool for planning waste management. A model is designed for the case study area in an Indian city for the purpose of planning waste management. The suggestions for amendments in the system through GIS based model would reduce the waste management workload to some extent and exhibit remedies for some of the SWM problems in the case study area. The waste management issues are considered to solve some of the present situation problems like proper allocation and relocation of waste bins, check for unsuitability and proximity convenience due to waste bin to the users, proposal of recyclable waste bins for the required areas and future suggestions. The model will be implemented on the Aurangabad city’s case study area data for the analysis and the results will suggest some modification in the existing system which is expected to reduce the waste management workload to a certain extent.</p>
55

Explore Hyderabad : An Interactive Web-based GIS Application Prototype

Hashmi, Mir Mahammed Hussain January 2006 (has links)
<p>Products are displayed in a shelf to market and sell to the public. It creates an interest and attracts people towards it. Likewise, any country or city can showcase itself by using Web over the internet which will attract the tourists from around the world. This example can be used for the city of Hyderabad. Hyderabad has truly become an international city and there are many multinational companies establishing themselves. It is rapidly becoming a hot spot for tourists from around the world because of its exotic locations and facilities provided by the government. The city has been famous for historical monuments and culture, but in the recent years it has developed into a world class IT destination for many multinational IT companies and due to this it has attained world recognition on the global scenario. The time is to reap the benefits of this image and promote the city’s tourist sector by globally marketing the tourist attractions, facilities and services in an innovative and better way so that tourists from around the world visit the city and thereby contribute to the country’s economy with the foreign currency.</p><p>This research deals with developing a Web-based GIS application that can promote the city’s tourist activities and also provide the users with an innovative way to access the spatial content of the city. GIS content forms the core component of this application as it provides the users with the spatial information about the place that is very close to reality. It supports the human tendency of “What you see is what you believe” by displaying the spatial information on the map. The application has been developed with the latest mapping server technology provided by Environmental Science Research Institute’s ArcIMS 9.1. This server software provides simple and easy methods to launch a Web-based GIS application over the Internet.</p>
56

Water quality modeling based on landscape analysis: importance of riparian hydrology

Grabs, Thomas January 2010 (has links)
Several studies in high-latitude catchments have demonstrated the importance of near-stream riparian zones as hydrogeochemical hotspots with a substantial influence on stream chemistry. An adequate representation of the spatial variability of riparian-zone processes and characteristics is the key for modeling spatio-temporal variations of stream-water quality. This thesis contributes to current knowledge by refining landscape-analysis techniques to describe riparian zones and by introducing a conceptual framework to quantify solute exports from riparian zones. The utility of the suggested concepts is evaluated based on an extensive set of hydrometric and chemical data comprising measurements of streamflow, groundwater levels, soil-water chemistry and stream chemistry. Standard routines to analyze digital elevation models that are offered by current geographical information systems have been of very limited use for deriving hydrologically meaningful terrain indices for riparian zones. A model-based approach for hydrological landscape analysis is outlined, which, by explicitly simulating groundwater levels, allows better predictions of saturated areas compared to standard routines. Moreover, a novel algorithm is presented for distinguishing between left and right stream sides, which is a fundamental prerequisite for characterizing riparian zones through landscape analysis. The new algorithm was used to derive terrain indices from a high-resolution LiDAR digital elevation model. By combining these terrain indices with detailed hydrogeochemical measurements from a riparian observatory, it was possible to upscale the measured attributes and to subsequently characterize the variation of total organic-carbon exports from riparian zones in a boreal catchment in Northern Sweden. Riparian zones were recognized as highly heterogeneous landscape elements. Organic-rich riparian zones were found to be hotspots influencing temporal trends in stream-water organic carbon while spatial variations of organic carbon in streams were attributed to the arrangement of organic-poor and organic-rich riparian zones along the streams. These insights were integrated into a parsimonious modeling approach. An analytical solution of the model equations is presented, which provides a physical basis for commonly used power-law streamflow-load relations. / At the time of doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: In press; Paper 4: Manuscript. / Swedish Research Council (VR, grant no. 2005-4289)
57

Tillämpning av GIS-analyser i MKB / Application of GIS-analyses in EIA

Wall, Erik January 2006 (has links)
The reason for performing an Environmental Impact Assessment (EIA) is to incorporate environmental concern in different kinds of plans and projects. The purpose of such an assessment is to identify and describe direct, indirect and cumulative environmental impacts. Geographical Information System (GIS) is a tool that can be used to combine spatial extension of both sensitive areas and different environmental impacts in a quick and easy way. Because of that, descriptions of environmental impacts and motivation of different standpoints on a specific issue can be more correct and easier to make if GIS is used as a tool. Hence, GIS can contribute to improve the quality of Environmental Impact Assessments. If the benefits of using GIS are to out weight the costs, geographical information of satisfactory detail, actuality and accuracy need to be available at reasonable prices. In this paper, case studies are carried out for three different geographical analyses to investigate the use of GIS as a tool in EIA. From these case studies, more general conclusions about the benefits and limitations of using GIS for Environmental Impact Assessments are also drawn. The criteria, after which benefits and limitations of GIS have been estimated, are data availability, time consumption for performing the analyses and how the results from the performed analyses can make impact assessments easier, motivate different standpoints and increase the comprehensiveness of the EIA-report. The three different GIS-analyses includes calculation of pollution load in a catchment area, estimation of the visual impact from planned buildings and generation of alternative locations for underwater pipes. These analyses have been applied on one ongoing EIA for a freight terminal and one ongoing EIA for an underwater wastewater transmission pipe. The analyses in these case studies have been undertaken with ArcGIS software using the extensions “Spatial Analyst” and “3D Analyst”. It is shown in this study that due to uncertainty in available model values and the time consuming data manipulation, it is unlikely that calculations of pollution loads with GIS will be used to any larger extent in EIA. To carry out visual assessments with help of GIS to estimate visual impacts is on the other hand assumed to be useful in EIA-work. Both to assess impacts and to estimate how changes in building design can alter those impacts. To use GIS to produce alternative locations for underwater pipes is also considered valuable in EIA-work, even though there is a considerable lack of data to predict the environmental class of marine areas and the connections between available data and real environmental values are weak. However, the risk of damaging vulnerable and high valued marine areas should decrease when applying this type of analyse. / Miljökonsekvensbeskrivningar (MKB) genomförs för att möjliggöra att hänsyn om miljön tas vid olika typer av exploateringsprojekt och exploateringsplaner. Syftet med en miljökonsekvensbeskrivning är att identifiera och beskriva direkta, indirekta och kumulativa miljöeffekter. Geografiska informationssystem (GIS) är ett verktyg som kan användas för att snabbt och enkelt kombinera rumslig utsträckning av både känsliga områden och olika miljökonsekvenser. GIS kan därför användas för att underlätta beskrivningar av miljökonsekvenser och motivera olika ställningstaganden. Därigenom kan GIS bidra till bättre grundade och mer rättvisande miljökonsekvensbeskrivningar. Men för att vinsterna av att genomföra GIS-analyser ska överstiga kostnaderna krävs att geografisk information av tillräcklig detaljeringsgrad, aktualitet och säkerhet finns att tillgå till rimliga kostnader. Syftet med denna studie har varit att genom fallstudier undersöka om tre olika GIS-analyser kan användas som verktyg i miljöbedömningar med idag tillgänglig data, samt att utifrån fallstudierna dra mer allmänna slutsatser om vinster och begränsningar av att använda GIS i miljökonsekvensbeskrivningar. De kriterier som har använts för att bedöma vinster och begränsningar är tidsåtgång för analyserna, tillgång på data samt hur analyserna kan vara ett stöd i MKB-arbetet genom att underlätta beskrivningar av konsekvenser, motivera ställningstaganden som görs och öka rapportens begriplighet. De tre genomförda GIS-analyserna innefattar beräkning av föroreningsbelastning inom ett avrinningsområde, bedömning av byggnaders landskapspåverkan genom synlighetsanalys samt generering av förslag till alternativ ledningsdragning för en undervattensledning. Dessa analyser har tillämpats på en pågående MKB för en detaljplan för en partihall och en pågående MKB för en avloppsvattenledning under vatten. Analyserna i fallstudierna har genomförts i programmet ArcGIS med tilläggen ”Spatial Analyst” och ”3D Analyst”. Studien visar att det på grund av osäkerheter i tillgängliga schablonvärden och tidsåtgång för databehandling är osannolikt att beräkning av föroreningsmängd inom ett avrinningsområde med GIS kommer att användas till någon större utsträckning i MKB. Att med GIS genomföra synlighetsanalyser för att utvärdera landskapspåverkan bedöms däremot kunna användas i MKB, både för att bedöma påverkan och för att utvärdera hur en förändring i en byggnads utformning kan förändra den påverkan. Även att med GIS generera förslag till alternativa ledningsdragningar under vatten bedöms kunna fylla en funktion i MKB trots att tillgången på data för att kunna beskriva olika marina områdens naturvärden är klart bristfällig och kopplingen mellan tillgängliga data och verkliga naturvärden är osäker. Denna typ av analys bör ändå minska risken att värdefulla och skyddsvärda marina områden skadas vid lednignsdragning.
58

Using GIS in Solid Waste Management Planning : A case study for Aurangabad, India

Shaikh, Moiz Ahmed January 2006 (has links)
Waste management is a global environmental issue which concerns about a very significant problem in today’s world. There is a considerable amount of disposal of waste without proper segregation which has lead to both economic and environment sufferings. It is still practiced in many cities. There is a tremendous amount of loss in terms of environmental degradation, health hazards and economic descend due to direct disposal of waste. It is better to segregate the waste at the initial stages where it is generated, rather than going for a later option which is inconvenient and expensive. There has to be appropriate planning for proper waste management by means of analysis of the waste situation of the area. This paper would deal with, how Geographical Information System can be used as a decision support tool for planning waste management. A model is designed for the case study area in an Indian city for the purpose of planning waste management. The suggestions for amendments in the system through GIS based model would reduce the waste management workload to some extent and exhibit remedies for some of the SWM problems in the case study area. The waste management issues are considered to solve some of the present situation problems like proper allocation and relocation of waste bins, check for unsuitability and proximity convenience due to waste bin to the users, proposal of recyclable waste bins for the required areas and future suggestions. The model will be implemented on the Aurangabad city’s case study area data for the analysis and the results will suggest some modification in the existing system which is expected to reduce the waste management workload to a certain extent.
59

Ειδική περιβαλλοντική - οικιστική μελέτη του συμπλέγματος λιμνοθαλασσών Μεσολογγίου - Αιτωλικού με τη χρήση Γεωγραφικών Συστημάτων Πληροφοριών (G.I.S) / Environmental study of the lagoons system Mesolongiou - Aitolikou with the use of Geographical Information Systems

Λαγκαδινού, Μαρία 28 June 2007 (has links)
Ο σκοπός της εργασίας αυτής είναι η πραγματοποίηση μιας περιβαλλοντικής μελέτης για την ευρύτερη περιοχή του συμπλεγματος λιμνοθαλασσών Μεσολογγίου - Αιτωλικού με τη χρήση Γεωγραφικών συστημάτων Πληροφοριών. Στην ερσασία αυτή γίνεται μια προσπάθεια χαρτογράφησης με την βοήθεια των ΓΣΠ με τους ακόλουθους στόχους¦ 1. Τη δημιουργία μιας βάσης σύγκρισης για τον συσχετισμό γεωλογικών και εδαφολογικών στοιχείων,και 2. Την εύρεση προτεινώμενων περιοχών, όπου μπορεί να αναπτυχθεί ένα μοντέλο οργανωμένης Οικιστικής Ανάπτυξης που θα πληρεί όλες τις προϋποθέσεις που θέτει το Υ.ΠΕ.ΧΩ.ΔΕ / The purpose of this work is an environmental study of the lagoons system of Mesolongi - Aitoliko with te use Geographycal Information Systems,with the two following directions: 1. To create a base of comparison between the geological and the soil data,and 2. To show an area where a new city could take place that follows all the instractions of Y.ΠΕ.ΧΩ.ΔΕ
60

Zoneamento ambiental como subsídio para a definição das áreas De preservação permanente

Gass, Sidnei Luís Bohn January 2015 (has links)
As discussões relacionadas às temáticas ambientais vêm tomando amplo espaço na sociedade nos últimos anos. No Brasil, um dos grandes reflexos que pôde ser observado foi à discussão em torno do Código Florestal (Lei Federal 12.651, de 25 de maio de 2012). Nesta discussão, um dos pontos mais polêmicos foram às novas definições em relação às Áreas de Preservação Permanente às margens dos cursos hídricos que, da mesma forma que ocorria na Lei Federal 4.771, de 15 de setembro de 1965, estão associadas a parâmetros métricos, que tomam por ponto de partida a largura dos cursos hídricos. No congresso nacional, duas forças bem demarcadas travaram uma longa batalha: o grupo dos ambientalistas, buscando resguardar condições mínimas de preservação e conservação ambiental e, o grupo dos ruralistas, que tomou por bandeira a produção de alimentos (e a sua falta) caso não se ocupasse a totalidade das áreas das propriedades rurais. Neste sentido, o objetivo geral da presente tese foi o de estruturar uma metodologia que considerasse os elementos da paisagem e do zoneamento ambiental como ferramentas para a definição dos parâmetros a serem adotados para a delimitação das Áreas de Preservação Permanente relacionadas ao entorno dos cursos hídricos, em distintas áreas da bacia hidrográfica do arroio Taquari-Miracatu, no sudoeste do Rio Grande do Sul, servindo como base para a estruturação de políticas públicas, normas técnicas e diretrizes de aplicação, que visem atender a diversidade socioeconômica e ambiental do território brasileiro. Para alcançar tal objetivo, buscou-se suporte teórico e metodológico nos conceitos de zoneamento ambiental e paisagem. A tese foi estruturada em níveis taxonômicos de análise, partindo da região hidrográfica do rio Uruguai, passando pelas bacias hidrográficas do rio Ibicuí e do arroio Taquari-Miracatu, até chegar às cinco áreas amostrais definidas como laboratório para a aplicação da metodologia em proposição. Como resultado desta análise e aplicação, foi possível verificar que os parâmetros legais hoje existentes, que se aplicam sobre as áreas amostrais, apresentam uma variação métrica de 30 a 50 metros a partir de cada margem do curso hídrico, o que não garante a função que as áreas ciliares devem exercer. Os resultados apresentados pela tese demonstram que, considerando parâmetros como solos, planícies fluviais e aluviais, usos do solo entre outros, esta distância pode chegar a mais de 1000 metros contados da margem do curso hídrico. O uso das geotecnologias foi um importante ferramental para a elaboração tanto do zoneamento ambiental como da própria definição das APPs. Como possibilidades futuras, cabem a busca por um procedimento metodológico que possa atender as demandas estaduais e nacionais bem como a integração de dados socioeconômicos com o intuito de qualificar o zoneamento a ser elaborado. / The discussions related to the environmental issues are taking ample space in society in recent years. In Brazil, one of the great reflexes that could be observed was the discussion on the Forest Code (Federal Law 12,651, of May 25, 2012). In this discussion, one of the most controversial points were the new definitions in relation to permanent preservation areas along the water courses, just as occurred in Federal Law 4771, of September 15, 1965, are associated with metric parameters, which It takes as its starting point the width of the rivers. At the national congress, two well demarcated forces fought a long battle: the group of environmentalists, seeking to safeguard the minimum conditions of environmental preservation and conservation, and the group of large farmers, who took the flag food production (and its lack) if not to occupy all the areas of rural properties. So, the general aim of this thesis was to design a methodology to consider the elements of landscape and environmental zoning as a tool for defining the parameters to be adopted for the delimitation of permanent preservation areas related to the environment of water courses, in different areas of the watershed of the Taquari-Miracatu basin in southwestern Rio Grande do Sul, serving as a basis for structuring public policies, technical standards and application guidelines, which aim to meet the socioeconomic and environmental diversity of Brazil. To achieve this goal, it sought theoretical and methodological support the concepts of environmental zoning and landscape. and methodological support the concepts of environmental zoning and landscape. The thesis was structured in taxonomic levels of analysis, started on the Uruguay River hidrological region, through the watershed of the river Ibicuí and Taquari-Miracatu, until you reach at the five sampling areas defined as a laboratory for the application of the methodology being proposed. As a result of this analysis and application, we found that today's existing legal parameters, which are applied to the sample areas, have a measuring range of 30 to 50 meters from each edge of the water course, which does not guarantee the function of the riparian areas. The results presented by the thesis show that, considering parameters such as soil, floodplains, land use and others, this distance can reach over 1000 meters counted from the edge of the water course. The use of geotechnology was an important tools for the development of both environmental zoning as the very definition of the APPs. As future research possibilities, fit the search for a methodological procedure that can meet local and national demands and the integration of socio-economic data in order to qualify the zoning to be prepared.

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