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A spatio-temporal urban expansion modeling a case study Teheran metropolis, Iran
10-19Views:113During the past decades, urban growth has been accelerating with the massive immigration of population to cities. Urban population in the world was estimated as 2.9 billion in 2000 and predicted to reach 5.0 billion in 2030. Rapid urbanization and population growth have been a common phenomenon, especially in the developing countries such as Iran. Rapid population growth, environmental changes and improper land use planning practices in the past decades have resulted in environmental deterioration, haphazard landscape development and stress on the ecosystem structure, housing shortages, insufficient infrastructure, and increasing urban climatological and ecological problems. In this study, urban sprawl assessment was implemented using Shannon entropy and then, Artificial Neural Network (ANN) has been adopted for modeling urban growth. Our case study is Tehran Metropolis, capital of Iran. Landsat imageries acquired in 1988, 1999 and 2010 are used. According to the results of sprawl assessment for this city, this city has experienced sprawl between 1988 to 2010. Dataset include distance to roads, distance to green spaces, distance to developed area, slope, number of urban cells in a 3 by 3 neighborhood, distance to fault and elevation. Relative operating characteristic (ROC) method have been used to evaluate the accuracy and performance of the model. The obtained ROC equal to 0.8366.
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Spatial distribution of vegetation cover in Erbil city districts using high-resolution Pléiades satellite image
10-22Views:206Green spaces are playing an essential role for ecological balance and for human health in the city as well. They play a fundamental role in providing opportunities for relaxation and enjoying the beauty of nature for the urban population. Therefore, it is important to produce detailed vegetation maps to assist planners in designing strategies for the optimisation of urban ecosystem services and to provide a suitable plan for climate change adaptation in one fast growing city. Hence, this research is an investigation using 0.5 m high-resolution multispectral Pléiades data integrated with GIS data and techniques to detect and evaluate the spatial distribution of vegetation cover in Erbil City. A supervised classification was used to classify different land cover types, and a normalised difference vegetation index (NDVI) was used to retrieve it for the city districts. Moreover, to evaluate the accessibility of green space based on their distance and size, a buffer zone criterion was used. The results indicate that the built-up land coverage is 69% and vegetation land cover is 14%. Regarding NDVI results, the spatial distribution of vegetation cover was various and, in general, the lowest NDVI values were found in the districts located in the city centre. On the other hand, the spatial distribution of vegetation land cover regarding the city districts was non-equal and non-concentric. The newly built districts and the districts far from the Central Business District (CBD) recorded the lowest vegetation cover compared with the older constructed districts. Furthermore, most of the districts have a lack of access to green spaces based on their distance and size. Distance and accessibility of green areas throughout the city are not equally distributed. The majority of the city districts have access to green areas within radius buffer of two kilometres, whereas the lowest accessibility observed for those districts located in the northeast of the city in particular (Xanzad, Brayate, Setaqan and Raperin). Our study is one of the first investigations of decision-making support of the spatial planning in a fast-growing city in Iraq and will have a utilitarian impact on development processes and local and regional planning for Erbil City in the future.
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Interferences between the ecological network and urbanized areas in Poland
65-77Views:35This paper presents spatial relations between Polish urban areas and valuable habitats and links between them composing the country’s ecological network. The quantitative analysis for 891 towns and cities was conducted using GIS techniques based on cartographic vector data and statistical data. Valuable habitats and links between them, such as national parks, landscape parks, CORINE biotopes sites, wildlife corridors linking NATURA 2000 sites and ECONET areas, can be found in 72% of Polish towns and cities. The proportion of artificial surfaces in those areas is different depending on the size of a town or city and its location. Urban areas with the highest index of presence of valuable habitats and links between them are concentrated in the south of Poland, where settlement network is most dense. However, in the case of those areas the proportion of artificial surfaces interfering with the ecological network is lower than Poland’s average, being 16%. The pressure of anthropogenic land cover extending onto the country’s ecological network is most conspicuous in urban areas with a population of at least several dozen thousand residents where the average developed area is 20.8% of their total area. The danger for the continuity of the nature system is best seen in the north western Poland, where artificial surfaces interference in towns and cities is largest. The analysis performed identified 82 towns and cities, in which the preservation of the continuity of the ecological network should be a priority in spatial management because of a higher than average index of the presence of valuable habitats and links between them and large proportion of artificial surfaces in those areas.
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Integrating applied lake ecology into spatial planning: towards a socially acceptable lakeshore restoration at Lake Velence (Hungary)
27-41Views:202A good chance of a socially accepted shore-restoration that is sustainable for the long run stands only, if all those, concerned in lake use, are also interested in the ecological interventions, if shore-restoration serves social and economic purposes, as well. In the previous phase of our research, assessments were made to find the sections of the shore zone that are suitable for restoration: to detect the sites where the existing artificial shoreline stabilization works could be removed. So that social demands should be involved in the assessment process, to begin with, structured interviews were made. According to the results, the share of the plots, being suitable or partially suitable for shore-restoration, slightly exceeded 7%. The analysis of restoration’s limiting factors has shown that the type of shoreline stabilization, the width of zone covered by emergent macrophytes, the extent of human pressures, and the relevant regulations on zoning (fixed in urban plans) together set limits to restoration. The interviews have made it clear that as a result of the changed demands on recreation-tourism, also the natural and landscape values have become more significant.
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The scenic value of abandoned mining areas in Poland
132-142Views:37Abandoned Polish mining areas are commonly heavily transformed so that they endanger no longer the environment. A disadvantage is that the newly created areas commonly contribute to the monotonous urban-industrial landscape, rather than providing additional value. This is partly due to legislation that hampers a more diversified management of abandoned mining areas as potentially valuable landforms. One of the legal barriers that restricts the possibilities of making these areas more attractive, regards the utilization of remaining exploitation holes (i.e. land depressions of at least 2 m deep, formed as a result of open-pit mining of energy, chemical, building or metallurgical resources) and waste heaps as important cultural and scenic elements. Such a new use of these old mininginduced phenomena is important if it is intended not only to involve the regional population in the process of exploring and exploiting the earth’s resources, but also to confront them with some negative consequences of these activities, including shaping the landscape in which these objects are situated. The current attitude towards a new architecture for abandoned mining areas should be reconsidered; particularly the present-day approach based on narrow specializations – for instance of experts in mineral exploitation, spatial planning or environmental protection – should be replaced by interdisciplinary action regarding shaping the landscape of abandoned mining areas.