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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

Development of management strategies for Kaoping River Basin using NPS pollution and river water quality models

Lai, Yu-Chang 16 August 2010 (has links)
The Kaoping River basin is the largest and the most intensively used river basin in Taiwan. It is 171 km long, drains a catchment of more than 3,257 km2, and has a mean flow of 239 m3/s. It serves as a water supply to the Kaohsiung City (the second largest city in Taiwan), several towns, two counties, and a number of large industries (electronic, steel, petrochemical, etc.). Although the mean annual rainfall in this river basin is close to 3,000 mm, over 90% of which appears in the wet season. The period of high flow rate in the stream usually occurs in the late spring and summer due to the impacts of monsoon and typhoon. Non-Point Sources (NPS) pollutants, which are associated with stormwater runoff from agricultural land uses can be quite diffuse and difficult to treat. In this study, land use identification in the basin was performed by properly integrating the skills of geographic information system (GIS) and global positioning system (GPS). Remote sensing image and Digital Elevation Model (DEM) of Kaoping River Basin were applied for the land use identification task. An integrated watershed management model (IWMM) was applied for simulating the water quality and evaluating NPS pollutant loads to the Kaoping River. The watershed was divided into catchments and river segments. The land use patterns were defined by the surface coverage of each catchment. The underneath soil can have several layers, and each land use has its vegetation characteristic and erosion coefficient. The model was calibrated and verified with field data from water quality monitoring stations. The calibrated model was used to develop best management practices (BMP). Moreover, the Water Quality Analysis Simulation Program (WASP) was also applied for the water quality simulation. The model was calibrated and verified with water quality data, and the model was used to analyze the impacts of NPS loading on water quality. The major objectives of this study were to (1) investigate and identify the current contributions of NPS pollutants to the Kaoping River pollution, (2) perform the land use identification and construct the watershed GIS to effectively manage the watershed, (3) perform water quality and soils sampling and analyses, (4) apply multimedia models for NPS pollution evaluation and water quality simulation, and (5) evaluate the effectiveness of the applied remedial strategies on watershed management and water quality improvement. This study identified major land-use patterns in Kaoping River Basin using SPOT images and GIS/GPS/RS techniques. The major findings from the GIS, field, and modeling tasks include the following: (1) Fourteen types of land-use patterns in the watershed area of the basin were classified with the aid of the Erdas Imagine process system; (2) Orchard gardens, rice paddies, sugarcane fields, betel palm farms, and tea gardens dominate the farmland areas in the basin and are scattered around on both sides of the river corridor; and (3) Simulated results indicate that NPS pollution plays a significant role in the deterioration of the downstream water quality of Kaoping River and caused a significant increase in suspended solids loads into the basin¡¦s water bodies. Concern about the deteriorating condition of the river led the Government of Taiwan to amend relevant legislation and strengthen the enforcement of discharge regulations to effectively manage the river and control pollution. Based on the results of this study, application of BMPs [e.g., source reduction, construction of grassy buffer zone, and land-use management] for NPS pollutant control are required. Multimedia modeling results indicate that the application of the following specific BMPs can reduce the effects of NPS suspended solids pollution on the water quality of Kaoping River: (1) Conversion of farmlands on hillsides of the upper catchment to forest; and (2) Conversion of rice paddies and agricultural lands to buffer zones (e.g., grassy strip, detention pond, and constructed wetland) along the riverbank areas of the three sub-basins. With application of these two proposed BMPs, the peak suspended solids concentrations in the wet seasons could be significantly reduced. Results and experience obtained from this study will be helpful in designing the watershed management strategies for other similar river basins.
52

Planning for Marine Protected Area - Case Study for Guishan Island

Shen, Cheng-Han 17 February 2011 (has links)
With the rapid development of the coastal environment and advances in fishing technology, marine biodiversity and fishery resources are decreasing dramatically. Therefore, each state is now focusing on conserving the marine environment. Planning Marine Protected Areas is one of the simplest and most efficient ways to do this. In recent years, researches have been conducted on Marine Protected Areas around the world. The government and academic fields in Taiwan also has started to value its surrounding marine environment. However, literature on the Marine Protected Areas in Taiwan has focused on policy and management, not so much on planning and zoning strategies. Therefore, this study uses the Geographic Information System (GIS) to simulate the planning and zoning process. This research set principles and zoning framework for Marine Protected Areas in Taiwan based on case studies and spatial analysis techniques. This study uses Gueishan Island in Yilan County as case study since the unique geographical environment of Gueishan Island provides potentiality to set Marine Protected Areas. In this study, it is suggested that "hot spring resources", "cetacean resources", and "fisheries resources" are the main protected objectives. The zoning strategies, management guidelines and recommendations are provided in this study based on these three protected objectives. According to the GIS simulation process, using the spatial analysis techniques is one of the possible efficient methodologies to plan and zone the Marine Protected Areas. With supplementary data and information, the results can be discussed more specifically in the further study. In addition, techniques of visualization during the MPAs zoning process can be a easier way for various stakeholders to understand, and to strengthen mutual communication, thereby reducing disputes to create successful Marine Protected Areas.
53

The Research of Hydrologic Management with GIS: A Case Study of the Aogu Wetland, Chiayi, Taiwan

Chang, Yu-Liang 08 September 2011 (has links)
Aogu Farm was built on reclaimed land. Because of its rich ecological resources, Aogu was defined as a "Major Wildlife Habitat" in Chiayi County by the Forest Service and is also expected to reduce carbon in the plan for the flatland forest. Power pumps are currently used to irrigate and cultivate the area. However, after becoming the Forest Recreation Area in the future, Aogu Farm has to reduce the influence of human beings. However, if the Taisugar Company doesn¡¦t support the plan of Forest Service or abandons farming and stops the pumping power, the Aogu Wetlands will suffer the crisis of coastal inundation. Hydrological models have their own characteristics. For example, inundation models for regional drainage using one-dimensional channel flow, two-dimensional overland flow, and runoff in the mountains all can be assessed to solve the inundation problems in the coastal lowlands. Nevertheless, the Aogu Wetlands, the Case Study area, has both a dry season and a wet season even in the lowland. When rainstorms occur, the area is unable to discharge the water by gravity but can depend only on pumps to discharge the water into the sea. Therefore, based on the need to manage water, hydrological surveys must be conducted to assess the hydrological impact of continuous rainfall on the Aogu Wetlands and to provide reference information to assist in the management. In the thesis, I use both the Geographic Information System (GIS) and the Storm Water Management Model (SWMM) as analysis tools. Moreover, the different regions are further divided into watershed and the route of drainage, establishing two kinds of models of watershed hydrology for precipitation simulations. Finally, to compare these two methods, the Arc Hydro and SWMM models are used in watershed analysis.
54

Effects of land use on island vegetation changes: A case study at Wangan and Chimei Islands, Penghu, Taiwan

Hsu, Chia-wen 08 September 2011 (has links)
Human activities, such as agricultural activity, housing construction, forest logging, etc., play an important role in vegetation changes. Any disturbance to the ecosystem by a severe change in landscape patterns may reduce the survival capacity of certain plant species. In recent years, many studies have used a geographic information system to establish spatial data on vegetation changes; this information includes both the plant species and their spatial structure. Therefore, the aim of this study is to investigate the trends and patterns of vegetation changes and the degree of correlation with the particular environmental features at Wangan Island and Chimei Island in the Penghu Islands, from 1979 to 2009. Both islands have very similar natural features, including geographic location, natural environment, and economic development, but the spatial structures of the land use type are different. The study makes use of geographic information systems, detrended correspondence analysis, canonical correspondence analysis and landscape ecological indicators as study tools. The results are expected to promote our understanding of the spatial distribution patterns of vegetation types and plant species. The results can be divided into three areas. First, both islands follow the same trend with regard to changes in land cover, but the rates of change are different. And the spatial structure of land use types affects the location of land cover types. Example, the centralized and decentralized villages both impact the distribution of the woodland. The mesh and ring road both impact the location of agricultural land. Second, the grassland plant species are correlated with the environmental factors, but the forest plant species are not. The major woodland specie is Leucaena leucocephala on both islands, whose physiological habits may reduce the degree of the correlation. Third, compared to the two islands, Chimei Island is more significant about that the vegetation types are correlated with the neighboring land use types. Finally, the plant species of the local vegetation types could be predicted by changes in the type of land use. In addition, this study has built a trend scheme of the spatial structure changes on Wangan Island and on Chimei Island, which can be used in the island¡¦s future environmental planning.
55

Vulnerability Assessment of an Island City with Respect to Pre-dicted Climate Change: Case Study of Makung City

Yeh, Cheng-chung 13 September 2012 (has links)
¡@¡@The isolation, separation, and self-contained characteristics of island environ-ments form the unique systems of ecology, culture, and landscape. Simultaneously, characteristics such as a lack of available area, high population density, and depend-ence on imports cause high vulnerability and low resilience in these isolated islands. There are 11 islands around Taiwan. Penghu is one of the islands in this area with the highest density. Under the impact of climate change, the vulnerability and the adapta-tion of the island¡¦s city may be affected. Therefore, Makung City served as a base for this study, which uses field observations and the collection of relevant literature, fol-lowed by spatial analysis methods and vulnerability assessment model analysis to de-termine the vulnerability of Magong City. The study¡¦s results and recommendations could provide a basis for policy on the island with respect to spatial planning and management. ¡@¡@To determine the sources of vulnerability on the island, vulnerability indicators can distinguish between the environment and society. However, up to now, we have not considered the difference between the islands near Taiwan. Therefore, the gov-ernment could not provide basic data to assess vulnerability. However, according to the limiting data of the vulnerability assessment results, the neighborhoods near the Makung port are in a high vulnerability area. If climate change continues with a sea level rise and storm surges, it may impact buildings near the coastal area of Makung City. In this study, the weight of vulnerability indicators was built by equal concep-tion to analyze the island¡¦s vulnerability wholly. Therefore, vulnerability research could try to build weight of island vulnerability in the future.
56

The Review and Prospect of Integrated Coastal Zone Management¡GCoastal Areas of Kaohsiung County as the Case

Shang, Rong-Kang 26 September 2000 (has links)
The coastal zone including coastal waters and littoral zone are influenced by the interactions between sea and land, and the resources of coastal areas have significant functions and values whatever the regards of nature ecology, industry development, transportation, tourism, national defense, and academic research. Following the population growth, economic advancement, and the change of industry, the land use of coastal zone is more diverse and complex. The incompatible between development and marine environment was happened sometimes. In order to solve the conflicts of coastal resources multiple use and mitigate the negative effects by human activities, integrated coastal zone management was become the most important way for sustainable using the sea. ¡§Integrated Coastal Zone Management (ICZM)¡¨ is a resource management system applying the process of integration, connection, and interaction, to analyze the complicated management problem at coastal areas. It is also a framework of principles and methodology for identification of important environmental priorities and allocation of scarce resources. It is an integrated management planning process emphasizing the comprehensive aspect to achieve the sustainable development of the coastal zone. Because the laws and regulations about land planning and coastal zone management is under legislation and the ¡§Coastal Zone Management Plan¡¨ of Kaohsiung County is not accomplished, the research attempts to understand the future development concept and direction about coastal areas in Kaohsiung County according to ¡§Kaohsiung County Comprehensive Development Plan¡¨. The research formulates some phenomena at present involving artificial construction causing coastal erosion, making land destroying the ecology, development project standing, development location overlapping, project contents competing each other, objective scale too large, disregard environmental sensitive areas, using a lot of hard structures, etc. Furthermore, we survey the planning and management of coastal zone through the aspects of integration among sectors, between the land and the water sides of the coastal zone, among levels of government, and among disciplines. Synthesizing the discussions of research, we can find the major problem of coastal zone management at Kaohsiung County is not lacking of planning project, instead of having too many but the implement result is not satisfactory. It is perceived that investigating and evaluating of the resource supply and the user demand at advance planning process was insufficient. Besides, it didn¡¦t have a comprehensive development plan which thinks about coastal environment from the first to be a basis of integration and coordination the various land use. Expecting the future coastal zone development and management, the responsible agency and project proponent can discard the departmental egoism, prior consider the integrated environment, proceed to communication, coordination, and integration continuously in search of a common consensus and vision. Only if that, the coastal zone development can be sustainable.
57

Determining transit impact on Seoul office rent and land value: an application of spatial econometrics

Kim, Jin 17 February 2005 (has links)
This study posits that there may be a systematic bias in measuring the transit’s endogenous impact on land values in a built up area due to discrimination by location in the city. Studies of transit value-added effect report mixed results about the capitalization of station proximity. The question is not whether a transit station influences nearby land values, but how and where location determines the impacts. Examining 731 office rentals and land values in Seoul, this study finds that value premium over better accessibility to a station decays with increasing distance from the central business district (CBD) and significantly depends on the development density of the station area. Overall, station benefits seem to exist in Seoul, but they look more notable in centers with higher centrality. This makes a hierarchy of regression coefficients for station proximity by location, i.e. the beta in the CBD is the highest and those in the subcenters are next, while that in other areas is the lowest. Study findings imply that the potential of more compact and denser developments within station areas seems higher in a dense inner city, providing evidence for the concept of ‘compact city.’ Questions concerning model specification in the hedonic approach are raised: in research sampled heavily from the suburbs, the coefficient may be underestimated where this benefit actually exists. Also, due to the incongruence of station area with station value-added area, using a dummy variable seems intrinsically risky. This study shows that estimation with spatial models outperforms OLS estimation in the presence of spatial autocorrelation. Also, there is a strong spatial autocorrelation even in the SAR residuals where the omission of key variables still influences the estimation. Overall, spatial lag and error term variables greatly improve the fitness of regression equations; however, the latter seemed more useful than the former in this study. One thing to note is that the latter seems more sensitive to the choice of weight matrix than the lag variable. There may exist a unique weight scheme proper for the data structure which cannot be known in advance.
58

Development of a Decision Support Geographic Information System for land restoration programs in the Leon, Lampasas, and Bosque River Watersheds

Jones, Jason Samuel 30 October 2006 (has links)
Ashe Juniper encroachment onto privately owned rangelands in Central Texas has resulted in significant degradation of the ecological condition of these lands, and a subsequent public concern for the hydrologic function, wildlife habitat, and livestock production these historically predominant grasslands provide. The result has been an interest and public investment in land restoration programs such as the removal and management of brush via landowner cost-share. Implementation of a publicly funded land restoration program requires the allocation of millions of dollars of public funds on private lands over large geographic areas that represent hundreds of landowners with varying property management objectives, tract sizes, ecological conditions, and geologic characteristics. This study describes the development, accuracy, and application of a decision support geographic information system (DSGIS) for land restoration programs in the Leon, Lampasas, and Bosque River watersheds in the Brazos River basin of Central Texas. The spatially referenced data layers and associated database within the DSGIS provide the capability to assemble site specific information including vegetation cover, endangered species habitat, landowners, ecological sites, elevation and slope, hydrologic characteristics, and political boundaries to support policy and implementation decisions for Ashe Juniper (Juniperus ashei) brush control and management and goldencheeked warbler (Dendroica chrysoparia) habitat restoration programs. The goldencheeked warbler is a federally listed endangered species with a breeding range limited to the oak-juniper woodlands of Central Texas. The data layers were developed with the support of ongoing research from the Leon River Restoration Project (LRRP) in Coryell and Hamilton counties. One hundred and eighty-eight (188) sub-watersheds were delineated within the project area and prioritized for implementation of an Ashe Juniper brush control program and a golden-cheeked warbler habitat restoration program. Costs associated with the clearing and stacking of Ashe Juniper were estimated for selected subwatersheds based on projected landowner participation and an analysis of actual costs from the LRRP. Sub-watersheds were targeted for the implementation of an Ashe Juniper brush control and golden-cheeked warbler habitat management program in Bosque, Coryell, Lampasas, Bell, and Burnet counties. Detailed tables were also developed to document the density and quantity of pertinent layer attributes within each of the 188 sub-watersheds.
59

Spatial analysis modeling for marine reserve planning¡Ðexample of Kaomei wetland

Chen, Chun-te 16 July 2008 (has links)
It is an internationally acknowledged that marine protected area (MPA) is an important measure for maintaining biodiversity and rescuing endangered species. MPA can also effectively inhibit human interferences such as development and pollution discharge. The establishment of MPA is possible to fulfill the goal of sustainable management, which is to conserve marine habitat for an integrative ecosystem and a higher biodiversity. However, how to design an effective MPA remains an important research issue to be explored. In order to grasp the spatial distribution of the ecological data in the study area, the current research uses spatial interpolation tool, Kriging, provided by the Geographic information system (GIS) software. Then three spatial analytical models have been developed based on integer programming techniques. It is guarantee that all three models can find the global optimal solutions for the best protective area partitions. This quantitative approach is more efficient and effective compared to the qualitative methods in many aspects. The models are able to preserve the maximum ecological resources under the limited spatial area. Besides, the model formulation can be adjusted from different environmental impact factors to fulfill the requirements of users. The case study of the research is to design a MPA for Kaomei wetland. However the spatial analytical models developed in this research can also be applied to protected area design in land area.
60

Walkability assessment in a transit-oriented development setting : a pilot study using a Geographic Information System

Chung, Myung Kyung 22 February 2012 (has links)
Many studies and land use planning attempts have done to influence people’s travel choices these days. Rather than sprawl development with automobile-dependent, single-use zoning, and cul-de-sacs, scholars and city planners now prefer and recommend more walkable, mixed-use development, and compact development. Along with neo-traditional development and pedestrian pockets, one trend of recent urban planning, Transit-Oriented Development (TOD), has attracted people’s attention. Given the new development of transportation methods, the present study explores how new transit stations will change people’s mobility and activity patterns. The main contribution of this project is to create an index of walkability attributions in a TOD setting based on previous research and to suggest assessment measures of walkability using a Geographic Information System (GIS). / text

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