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Use Of Cuencas hydrological model in simulating the effects of land use change on the 2008 flooding event in the Turkey River WatershedPerez Gonzalez, Maria Fernanda 01 July 2011 (has links)
East Iowa experienced large flooding during June of 2008. This study used Cuencas hydrological model to simulate the discharges of June 2008 at Eldorado and Elkader, in the Turkey River Watershed, in North East Iowa. The results of this study were used to test the performance of Cuencas modeling this flood event and to explore the role of land cover change in the floods of 2008 at Elkader, Iowa.
Cuencas was found to be a suitable tool to predict this event, that requires relatively low resources. The total time to run each simulation was around two hours which is reasonable for such large watershed (900 mi2), but a computer cluster was needed to run these simulations.
The results from this study suggest that the role of land cover change from pre-settlement to current conditions was significant when using the rainfall conditions of 2008. The discharges simulated at Elkader, Iowa were almost twice as large when using the 2001 land cover, than when using the land cover found during 1832-1859, recorded during the General Land Office (GLO) survey. These results need to be taken only as preliminary results, since there is no data to validate the model at the time of the GLO survey, and since it is the first time that Cuencas is used to model the effects of land cover in Iowa's hydrology. However, the potential large reduction on discharge of the pre-settlement land cover is an incentive to investigate this issue further and continue developing Cuencas to capture the effects of less drastic land cover changes.
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A Comparative Study on Coastal Zone Changes and Anthropogenic Impacts between Tampa Bay, USA, and Xiangshan Harbor, China, during the Last 30 YearsGuo, Qiandong 28 June 2018 (has links)
Currently, the U.S. and China are the two largest national economic entities in the world. However, it is noticeable that the two countries have considerably different strategies for economic development, environmental protection and land supply in coastal zones. In order to understand the coastline dynamics, land use land cover (LULC) changes and land management policies in the U.S. and China, a case study of the Tampa Bay (TB) watershed, Florida, U.S., and Xiangshan Harbor (XH), Zhejiang Province, China was conducted. The two areas possess similar humid subtropical climate and dense population, but experienced different anthropogenic impacts. TB sat at a developed stage with sound environmental laws, regulations and projects to preserve natural landscapes. XH was at a developing stage and focused more on an economic development in the last 30 years. Comparing the LULC change patterns and the major driving forces for the changes between the two study areas, governments and public could know what factors cause the land use conversion and how to preserve the natural landscapes. A new water index called the weighted normalized water index (WNDWI) was proposed to extract coastlines in TB and XH since current water indices could not classify turbid water bodies and shadow areas well. Two threshold methods (i.e., Otsu threshold method and multiple thresholds method) were implemented to find an optimal threshold to segment the water from the land. The experiments demonstrate that the WNDWI algorithm can achieve high accuracies to classify water from land with an optimal threshold in the two study sites. Coastlines in 1985, 1995, 2005 and 2015 in TB and XH were extracted and the changes were detected and highlighted. The results indicate that coastlines in TB were mostly stable, while those in XH had been undergoing intensive human interferences, indicating that XH was at a developing stage. Major anthropogenic impacts on XH coastlines are land reclamation and aquaculture, resulting in an impacted area of approximately 20.3 km2. The land cover maps of TB and XH in 1985 (1986), 1995, 2005 and 2015 were produced by classifying Landsat images using the random forest algorithm. The reflectance distributions of the land cover types indicate that it is difficult to classify agricultural land, rangeland, upland forest and wetland if using the optical bands only from a single Landsat image. Multi-seasonal image composites and the land surface temperature (LST) band were involved in image classification to achieve higher accuracies. The overall accuracies (OAs) of the land cover map of TB in 2015 and that of XH in 2005 were increased by 5.14% and 4.33% after adding the LST band. The OAs of the four years’ land cover maps of TB range from 81.14% to 83.43%, whereas those of XH vary from 84.67% to 87.67%. According to the experimental results, the total urban area increased by 11.8% in TB, while that in XH increased 138.9% during the last 30 years. Wetland in TB reduced by 8.3% while that in XH reduced 49.0%. The results of logistic regression analysis indicated that the density of wetland is a major driver for urban growth in TB with a strong negative impact while the relationship is opposite in XH. It is worth noting that XH has been undergoing a rapid urbanization and industrialization process with a vast amount of natural landscapes converted to urban areas, whereas TB has already passed the developing stage and issued environmental laws and programs to preserve natural landscapes from human exploitation. In terms of preserving natural landscapes and protecting the vulnerable coastal environment for our next generation, the coastal planning decision makers in XH should not only consider economic values and short-term benefits but also integrate values of ecological, social, and cultural and long-term benefits when making coastal management decisions.
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Land Use and Land Cover Change Detection in Isfahan, Iran Using Remote Sensing TechniquesAlavi Shoushtari, Niloofar 09 May 2012 (has links)
Rapid urban growth and unprecedented rural to urban transition, along with a huge population growth are new phenomena for both high and low income countries, which started in the mid-20th century. However, urban growth rates and patterns are different in developed countries and developing ones. In less developed countries, urbanization and rural to urban transition usually takes place in an unmanaged way and they are associated with a series of socioeconomical and environmental issues and problems. Identification of the city growth trends in past decades can help urban planners and managers to minimize these negative impacts. In this research, urban growth in the city of Isfahan, Iran, is the subject of study. Isfahan the third largest city in Iran has experienced a huge urban growth and population boom during the last three decades. This transition led to the destruction of natural and agricultural lands and environmental pollutions.
Historical and recent remotely sensed data, along with different remote sensing techniques and methods have been used by researchers for urban land use and land cover change detection. In this study three Landsat TM and ETM+ images of the study site, acquired in 1985, 2000 and 2009 are used. Before starting processing, radiometric normalization is done to minimize the atmospheric effects. Then, processing methods including principal component analysis (PCA), vegetation indices and supervised classification are implemented on the images. Accuracy assessment of the PCA method showed that the first PC was responsible for more than 81% of the total variance, and therefore used for analysis of PCA differencing. ΔPC1t1-t2 shows the amount of changes in land use and land cover during the period of study. In this study ten vegetation indices were selected to be applied to the 1985 image. Accuracy assessments showed that Transformed Differencing Vegetation Index (TDVI) is the most sensitive and accurate index for mapping vegetation in arid and semi-arid urban areas. Hence, TDVI was applied to the 2000 and 2009 images. ΔTDVIt1-t2 showed the changes in land use and land cover especially the land use transformation from vegetation cover into the urban class. Supervised classification is the last method applied to the images. Training sites were assigned for the selected classes and accuracy was monitored during the process of training site selection. The results of classification show the expansion of urban class and diminishment in natural and agricultural lands.
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Exurban land cover and land market evolution: Analysis, review and computational experimentation of spatial and agent heterogeneity from the bottom upHuang, Qingxu 22 January 2013 (has links)
This dissertation investigates selected empirical and theoretical aspects of land-use and land-cover change (LUCC) in exurban areas. Two challenges – observation and monitoring of LUCC, and spatially explicit modeling, are addressed using three main approaches – measuring, reviewing and agent-based modeling (ABM). All of these approaches focus on LUCC at the individual household level, investigating how micro-scale elements interact to influence macro-scale functional patterns—bottom-up analysis.
First, the temporal change of the quantity and pattern of land-cover types within exurban residential parcels in three townships in the southeastern Michigan is examined using landscape metrics and local indicators of spatial association at the parcel and parcel-neighborhood level respectively. The results demonstrate that the number and area of exurban residential parcels increased steadily from 1960 to 2000, and different land-cover types have distinctive temporal changes over time. The results also indicate that there is a convergence process at the neighborhood level through which the quantity and pattern of land cover in parcels conform with the neighborhood appearance.
Second, 51 urban residential choice models based on ABM are reviewed. The results divide these models into three categories (i.e. models based on classical theories, models focusing on different stages of urbanization process; and integrated ABM and microsimulation models). This review also compares the differences among these models in their representations of three essential features brought by the technique of ABM: agent heterogeneity, the land market and output measurement. Challenges in incorporating these features, such as the trade-off between the simplicity and abstraction of model and the complexity of urban residential system, interactions of multiple features and demands for data at individual level, are also discussed.
Third, the effects of agent heterogeneity on spatial and socioeconomic outcomes under different levels of land-market representations are explored through three experiments using a stylized agent-based land-market model. The results reveal that budget heterogeneity has prominent effects on socioeconomic outcomes, while preference heterogeneity is highly pertinent to spatial outcomes. The relationship between agent heterogeneity and macro-measures becomes more complex as more land-market mechanisms are represented. The results also imply that land-market representation (e.g., competitive bidding) is indispensable to reproduce the results of classical urban land market models (e.g., monocentric city model) in a spatial ABM when agents are heterogeneous.
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Monitoring land use and land cover change: a combining approach of change detection to analyze urbanization in Shijiazhuang, ChinaLiu, Qingling, Gong, Fanting January 2013 (has links)
Detecting the changes of land use and land cover of the earth’s surface is extremely important to achieve continual and precise information about study area for any kinds of planning of the development. Geographic information system and remote sensing technologies have shown their great capabilities to solve the study issues like land use and land cover changes. The aim of this thesis is to produce maps of land use and land cover of Shijiazhuang on year 1993, 2000 and 2009 to monitor the possible changes that may occur particularly in agricultural land and urban or built-up land, and detect the process of urbanization in this city. Three multi-temporal satellite image data, Thematic Mapper image data from year 1993, Enhanced Thematic Mapper image data from 2000 and China Brazil Earth Resource Satellite image data from 2009 were used in this thesis. In this study, supervised classification was the major classification approach to provide classified maps, and five land use and land cover categories were identified and mapped. Post-classification approach was used to improve the qualities of the classified map. The noises in the classified maps will be removed after post-classification process. Normalized difference vegetation index was used to detect the changes of vegetated land and non-vegetated land. Change detection function in Erdas Imagine was used to detect the urban growth and the intensity of changes surrounding the urban areas. Cellular automata Markov was used to simulate the trends of land use and cover change during the period of 1993 to 2000 and 2000 to 2009, and a future land use map was simulated based on the land use maps of year 2000 and 2009. From this performance, the cross-tabulation matrices between different periods were produced to analyze the trends of land use and cover changes, and these statistic data directly expressed the change of land use and land cover. The results show that the agricultural land and urban or built-up land were changed a lot, approximately half of agricultural land was converted into urban or built-up land. This indicates that the loss of agricultural land is associated with the growth of urban or built-up land. Thus, the urbanization took place in Shijiazhuang, and the results of this urban expansion lead to the loss of agricultural land and environmental problems. During the process of detecting the land use and cover change, obtaining of high-precision classified maps was the main problem.
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Exploring the effects of local development regulations on ecological landscape structureKim, Jin Ki 29 August 2005 (has links)
An ecological approach to land-use planning is essential to maintain the long-term
sustainability of ecosystem benefits, services, and resources. Concern about
environmental quality and the long-term livability of urban areas is now a driving force
in urban planning and design. The interrelated issues of growth management, smart
growth, sustainable development, and new urbanism are topics in the most vibrant
discussions at all levels of planning and landscape architecture. Within this context, this
study starts from the interest in the ecological planning and management in urban areas,
especially related to the issue of local development regulation and guidelines. Landscape
regulations have come into existence recently in communities across the nation and these
regulations vary from one region to another and from one community to another.
The aims of this study were to investigate the relationship between ecological
landscape structure and local development regulations over time. Comparison analysis
was conducted between two areas that had similar pre-development ecological
conditions but were developed under vastly different regulatory environments. The
Woodlands (regulated to protect ecological condition) and the North Houston area
(which followed traditional subdivision regulations) were examined at three different
developmental time periods: predevelopment, early development (after 10 years), and
matured development (after 30 years). Aerial photos of each site from the three time
periods were classified into forested and non-forested classes and the landscape structure
was quantified with a number of landscape metrics related to fragmentation??an
indicator of habitat degradation. Two factors, the ecological approach to landscape
planning and the adoption of more restrictive landscape regulations and guidelines, are
discussed on the premise that they exert influence in developing and maintaining the
long-term sustainability of ecosystems.
In conclusion, this study provides the quantified landscape configuration and
composition of the effects of development regulations on landscape structure. The
ecologically planned community shows a less fragmented forest pattern and more
restrictive development guidelines result in more ecologically structured environments.
Understanding how elements of local development regulations affect ecological
landscape patterns is important for landscape architects, planners, and administrators
because it can lead to better strategies for planning and designing sustainable
communities.
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An analysis of forest change : a case study of the Chocó-Andean conservation corridor in the Upper Guayllabamba Watershed, EcuadorGordon, Jessica Danielle 01 December 2010 (has links)
Deforestation in the tropics is considered to be a primary cause for worldwide loss
of biological diversity. Future land use decisions have the potential to escalate or
ameliorate this global problem. The goal of this research is to present a case study of an
analysis of forest change within the Chocó-Andean Conservation Corridor in the Upper
Guayllabamba Watershed in Northwestern Ecuador. Fieldwork, remote sensing, and a
Geographic Information System (GIS) were used to analyze land use/land cover changes
within the corridor. Change detection from 1986 to 2001 using Landsat imagery
confirmed that forests were rapidly being converted to other land covers, but patterns of deforestation rates varied dramatically for different types of forests. The average annual
rate of overall loss of forest was 2.7% for lower montane forest, 1.7% for mid-slope
cloud forest 2.1% for upper montane forest, and 2.0% for riparian forests. The patterns
of deforestation also varied based on scales of analysis. For example, the overall loss of
forest within the southern portion of the Chocó-Andean Conservation Corridor occurred
at an average rate of 1.3% per year, while the overall annual rate of forest loss within
particular sub-watersheds varied from 0.2%-3.1% and the annual average rate of overall
forest loss surrounding particular communities ranged from 0.3%-3.3%. Fifty interviews
were conducted in 2003 in seven communities within the conservation corridor to
determine local perspectives of current land use practices, past land use trends, and future
land use goals; regional changes in the forest; and opinions of local conservation projects.
An intriguing finding of the study is that remote sensing in isolation of fieldwork would
have provided incomplete or misleading results. For example, the community that had
the most deforestation between 1986 and 2001 was the community where the
conservation projects were actually the most successful, based upon local resident
opinion. This report asserts that a holistic approach to conservation is needed to
reconcile environmental and socio-cultural needs in order to maintain and improve forest
habitat and hydrologic connectivity at multiple spatial scales (including community-level,
watershed, and regional) by extending conservation efforts beyond protected areas and
utilizing a basin-scale perspective to make land use decisions that maintain biodiversity
and promote watershed protection. / text
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Land Use and Disturbance Interactions in Dynamic Arid Systems: Multiscale Remote Sensing Approaches for Monitoring and Analyzing Riparian Vegetation ChangeVillarreal, Miguel Luis January 2009 (has links)
Riparian systems are comprised of interacting aquatic and terrestrial elements that contribute distinctively to the natural capital of arid landscapes. Riparian vegetation is a major component of riparian systems, providing the ecosystem services required to support watershed health. The spatial and temporal distributions of riparian vegetation are influenced by hydrologic and disturbance processes operating at scales from local to regional. I believe both these processes are well suited to monitoring using synoptic and multitemporal approaches.The research in this dissertation is presented as 3 related studies. The first study focused on historical riparian dynamics related to natural disturbance and land use. Using current and historical riparian vegetation maps, we examined vegetation change within catchments of varying land use intensity. Results suggest that land use activities and wastewater subsidy affect the rate of development and diversity of riparian community typesThe second study used moderate resolution satellite imagery to monitor changes in riparian structure and pattern within a land cover change framework. We classified Landsat Thematic Mapper satellite imagery of the Upper Santa Cruz River watershed using Classification and Regression Tree (CART) models. We tested the ability of our models to capture change at landscape, floodplain, and catchment scales, centering our change detection efforts on a riparian tree die-off episode and found they can be used to describe both general landscape dynamics and disturbance-related riparian change.The third study examined historical and environmental factors contributing to spatial patterns of vegetation following two riparian tree die-offs. We used high resolution aerial imagery to map locations of individual live and dead trees and collected a suite of environmental variables and historical variables related directly and indirectly to land use and disturbance history. We tested for differences between groups of live and dead trees using Multi-response Permutation Procedures and found strong relationships between historical factors and mortality incidence.The results from these studies demonstrate the importance of examining historical information and spatial linkages across scales when monitoring riparian vegetation. From a land management perspective, the results identify the need for landscape-level, ecosystem-based management programs to maintain functioning and spatially connected riparian systems.
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Exploring human-environment interactions and their effects around Ngel Nyaki Forest Reserve, NigeriaKorndoerfer, Martin Christoph January 2010 (has links)
Many protected areas around the world face degradation in the face of poverty, maladapted agricultural practices and population growth in their surroundings. This research uses a multidisciplinary approach to study this complex problem in the context of a montane ecosystem. The study area comprises Ngel Nyaki and Kurmin Danko Forest Reserves on the Mambilla Plateau in Eastern Nigeria and the surrounding landscape, comprising pastoral lands, farmland, villages and homesteads.
Ongoing degradation of the Forest Reserves through their illegal use as grazing areas by the local Fulani pastoralists indicates that the exclusionary protection of the forest is not working. It may be that a participatory forestry approach to conservation would be more successful. The research presented in this thesis uses a variety of methods (interviews, remote sensing, geographic information systems (GIS) and ecological monitoring) to evaluate the current situation in the study area with the aim of determining the likelihood of such a participatory approach to conservation being successful.
Satellite images from the years 1988, 2000 and 2009 were used to quantify changes in forest cover to measure deforestation and regeneration rates. Interviews were used to understand the Fulani's pastoral management systems, land ownership status, cattle movements and living situation. Data from interviews and observations as well as from satellite imagery were combined in a GIS to approximate stocking rates and property boundaries and to identify the level of livelihood diversification the different Fulani families have undergone. As grass and water availability have been identified as the main environmental factors determining grazing and cattle movements, environmental data was collected to determine changes in the rates of grass productivity and streamflow over the course of one dry season.
The study found that the extent of natural forest is decreasing all over the study area, on privately owned properties, commonly owned properties and in the Forest Reserves. Evidence of human impacts such as charred grassland by late burning and cattle tracks were clearly visible throughout the reserves, with the exception of the core forest area, indicating ongoing intensive use and management of the reserve for cattle grazing. The stocking rates in dry and wet seasons have been found likely to exceed carrying capacities, which results in overgrazing and a reduction in vegetation cover.
The Fulani in the study area have already undergone a transition from relying purely on livestock and livestock products to relying on a mix of livestock, agriculture and silviculture. This transition shows potential for forest transition according to the 'forest transition theory', which, supported by the right policy incentives could be transformed into landscape scale conservation of endemic flora and fauna.
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Biomass productivity and water availability in wet and dry seasons were found to be highly asymmetric, which seriously restricts the number of suitable cattle management systems.
Data indicate that tall riverine vegetation may have effects on stream water availability during the dry season. The findings of this section point to the need of carefully reassessing the current management of tall riverine vegetation on the Mambilla plateau, also in view of the sustainability of the water supply for pastoral livelihoods.
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Land Use and Land Cover Change Detection in Isfahan, Iran Using Remote Sensing TechniquesAlavi Shoushtari, Niloofar 09 May 2012 (has links)
Rapid urban growth and unprecedented rural to urban transition, along with a huge population growth are new phenomena for both high and low income countries, which started in the mid-20th century. However, urban growth rates and patterns are different in developed countries and developing ones. In less developed countries, urbanization and rural to urban transition usually takes place in an unmanaged way and they are associated with a series of socioeconomical and environmental issues and problems. Identification of the city growth trends in past decades can help urban planners and managers to minimize these negative impacts. In this research, urban growth in the city of Isfahan, Iran, is the subject of study. Isfahan the third largest city in Iran has experienced a huge urban growth and population boom during the last three decades. This transition led to the destruction of natural and agricultural lands and environmental pollutions.
Historical and recent remotely sensed data, along with different remote sensing techniques and methods have been used by researchers for urban land use and land cover change detection. In this study three Landsat TM and ETM+ images of the study site, acquired in 1985, 2000 and 2009 are used. Before starting processing, radiometric normalization is done to minimize the atmospheric effects. Then, processing methods including principal component analysis (PCA), vegetation indices and supervised classification are implemented on the images. Accuracy assessment of the PCA method showed that the first PC was responsible for more than 81% of the total variance, and therefore used for analysis of PCA differencing. ΔPC1t1-t2 shows the amount of changes in land use and land cover during the period of study. In this study ten vegetation indices were selected to be applied to the 1985 image. Accuracy assessments showed that Transformed Differencing Vegetation Index (TDVI) is the most sensitive and accurate index for mapping vegetation in arid and semi-arid urban areas. Hence, TDVI was applied to the 2000 and 2009 images. ΔTDVIt1-t2 showed the changes in land use and land cover especially the land use transformation from vegetation cover into the urban class. Supervised classification is the last method applied to the images. Training sites were assigned for the selected classes and accuracy was monitored during the process of training site selection. The results of classification show the expansion of urban class and diminishment in natural and agricultural lands.
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