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Spatial distribution of vegetation cover in Erbil city districts using high-resolution Pléiades satellite image
10-22Views:190Green 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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Landscape change in Aizawl city: A geospatial approach to assess landscape indices and human-induced transformation
65-81Views:213The change in an area’s natural surroundings is called landscape change. This change may be gradual or accelerated depending on the factors that influence the change. Natural elements such as native animals and birds seldom bring about any modification to the environment. However, human-induced change is devastating and severely transforms the environment. Such environmental transformation can be evaluated with the land use/ land cover assessment through satellite imagery and calculation of landscape indices. This paper attempts to ascertain the direction and the nature of the human-induced change in the city of Aizawl. To this end, the city has been divided into four zones to enable inter-zone comparisons. A northeast and southwest direction of human landscape transformation has been ascertained with the help of GIS and remote sensing techniques and landscape indices in Aizawl city.
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Wind damage on trees following hurricane Sandy and implications for city landscaping: Glen Ridge - Montclair towns, New Jersey
1-11Views:67Glen Ridge is a small municipality in the Northern New Jersey with a significant number of huge trees lining majority of its streets. The trees have been subject to a wide range of natural and artificial stresses, one being the strong wind associated with superstorm Sandy. On 29th October 2012, a windstorm of extreme intensity struck the Tristate region and brought havoc to the tree population including those in Glen Ridge. A survey was conducted immediately after the storm to collect quantitative information on fallen tree population. The study aimed at understanding the spatial extent of wind damage on trees with reference to location, trunk diameter and soil characteristics. A total of 51 fallen trees with a mean trunk diameter of 100.4 centimetres along streets in study area were surveyed. High damage was noted on trees in Glen Ridge (29 trees) while streets transitioning to Montclair had 22 fallen trees. Majority of the surveyed trees were found on USBOO soils (49%), which are characterised as disturbed urban soils with Boonton substratum-Boonton complexes. BowrB soils had 27.5%, Boob 13.7%, BowrC 7.8% and USDUNB 2.0% of fallen trees. A need for city wide tree inventorying and species mapping is identified as a management implication to further enhance the historical value of the city. Other measures are discussed with a view of engaging appropriate local management partnerships and coordination frameworks to play a role in protecting the remaining large trees.
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Characterization of urban aerosol sources in Debrecen, Hungary
109-119Views:52Debrecen is an average middle European city from the point of view of aerosol pollution. Its location makes the city an ideal place for observing aerosol transport processes. Systematic investigation of atmospheric aerosol of the east-Hungarian region has been performed in the Institute of Nuclear Research of the Hungarian Academy of Sciences for 20 years by accelerator based elemental analytical technique. As a complementation of this research we observed the size distribution and short-term time variation of the elemental component of fine (PM2.5) and coarse (PM10-PM2.5) urban aerosol in the frame of sampling campaigns during 2007 and 2008 in a downtown site of Debrecen. Meteorological parameters were also recorded parallel to the aerosol sampling. Elemental concentrations (Z ≥ 12) were determined by particle induced X-ray emission (PIXE) analytical technique at the Laboratory of Ion Beam Applications (IBA) of the ATOMKI. On the obtained database six sources of the urban aerosol were identified: 2 types of soil, domestic heating, sulphate originating from long range transport processes, an unidentified source enriched with chlorine and traffic. Emission episodes were also observed. The short-time variation of urban aerosol combined with meteorological data and with mass size distribution serves as a basis to reach a better understanding of the aerosol sources in receptor areas, to select local emission and long range transport episodes, to follow the evolution of aerosol, and to make a better estimate on the health impact.
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History of the meteorological observatoions in Debrecen
1-5Views:31Debrecen was among the first cities in Hungary where meteorological observatories were established, although the weather station of our University was put into operation 80 years ago, Meteorological observations have a much longer history in the city. In the present paper history of the meteorological observations and stations worked in the city has been reviewed with special emphasis on the meteorological observatory of the University of Debrecen.
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A spatio-temporal urban expansion modeling a case study Teheran metropolis, Iran
10-19Views:104During 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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Correction of Atmospheric Haze of IRS-1C LISS-III Multispectral Satellite Imagery: An Empirical and Semi-Empirical Based Approach
63-74Views:247The atmospheric effect greatly affects the quality of satellite data and mostly found in the polluted urban area in the great extent. In this paper, the atmospheric correction has been carried out on IRS-1C LISS-III multispectral satellite image for efficient results for the Raipur city, India. The atmospheric conditions during satellite data acquisition was very clear hence very clear relative scattering model of improved dark object subtraction method for the correction of atmospheric effects in the data has been carried out to produce the realistic results. The haze values (HV) for green band (band 2), red band (band 3), NIR band (band 4) and SWIR (band 5) are 79, 53, 54 and 124, respectively; were used for the corrections of haze effects using simple dark object subtraction method (SDOS). But the final predicted haze value (FPHV) for these bands are 79, 49.85, 21.31 and 0.13 that were used for the corrections of haze effects applying improved dark object subtraction method (IDOS). We found that IDOS method produces very realistic results when compared with SDOS method for urban land use mapping and change detection analysis. Consequently, ATCOR2 model provides better results when compared with SDOS and IDOS in the study.
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Prediction of industrial land use using linear regression and mola techniques: A Case Study of Siltara Industrial belt
59-70Views:258The Siltara Industrial belt is an important industrial pocket of Chattisgarh state located in the northern part of the Raipur city, which is rapidly growing. In this process spatial, cultural, political and administrative factors are controlling its rate, direction and pattern. The Simple Linear Regression (SLR) and Multi-Objective Land Allocation (MOLA) techniques, which are embedded in SPSS and Idrisi Kilimanjaro software respectively, and have been used for the estimation of future scenario of the industrial growth. In this model, a suitable platform has been prepared in which future industrialization has been estimated by integrating physical, social, cultural factors and land acquisition policy. In this article, results have revealed that industrialization has occurred very fast during last one decade. The industrial land was 6.15 km2 in 2001 and 18.725 km2 in 2011 and estimated as 31.30 km2 in 2021 and 43.87 km2 in 2031 using SLR. The rapid industrial growth is very critical issues for agrarian society and fresh environment. This model very accurately estimating (overall accuracy=95.39%, Kno=97.24%, agreement=98.63 %) the future growth of industrial land. This work will be useful to the planners and policy makers of private and government sectors to regulate the sustainable planning practices and smart decision-making.
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Interferences between the ecological network and urbanized areas in Poland
65-77Views:27This 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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Landscape shape index, as a potencial indicator of urban development in Hungary
78-88Views:348The study of settlement shape, morphology and structure is a classic topic of urban geography. Since the 1960s multiple shape indices have been developed. Urban patterns were then compared with geometric forms or, alternatively their temporal changes were tracked and analysed. In the current study we adapted the landscape shape index (LSI) to analyse the historical shape development of eight Hungarian cities. The LSI is capable to demonstrate the functional and mutual relationship between the developed area and their immediate physical and natural environment. Over the past 230 years the land area of the studied cities has increased manifold for several reasons: on average, an areal increase of 10.4 to 24.5 was observed for the eight settlements, while their perimeter increased by 8.8 to 30.3 times. Simultaneously with their size growth, the studied cities are characterized by an increasingly fragmented and dissected ground plans. Consequently, due to the longer border between the developed areas and the adjacent natural zones, urban areas have become increasingly sensitive to environmental effects over the past century, while mutual ecological and environmental interactions has also considerably increased between the adjoining zones. In general, cities of hilly and low-mountain areas had the highest LSIs, whereas cities located on relatively flat grounds had comparatively low LSIs. We also investigated the rank correlation of the historical change of LSI of the studied settlements. Cities of high positive correlations (> 0.9) were classified into two major categories. Miskolc, Pécs, Szeged and Kecskemét belonged to the group of higher LSIs, whereas Székesfehérvár and Nyíregyháza fell into the class of medium LSIs and the third category included Debrecen and Győr, cities of low (< 0.9) LSIs. Based on the temporal trends of the LSIs, our results provide applicable information for decision makers in order to monitor, manage and track their investments, city management policies and infrastructural development strategies.
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Heavy metal loads in the soil of Debrecen
57-67Views:41Results of examinations on the amount, and spatial distribution of heavy metal compounds in the soil of Debrecen, their geographic, pedologic and ecologic aspects are presented in this study. The effects of the differences in traffic conditions, build-up/land use and the density of vegetation on the heavy metal content of the soils have been examined in city of Debrecen and its closer environment. Cadmium-, cobalt-, nickel-, lead-, and copper-contents of the soil samples taken from 88 sites of the sample area have been studied after acidic extraction, using atomic absorption spectrometer with the flame technique. Close-to-background concentrations of heavy metals in unpolluted soils of the forested area of the Nagyerdő were determined. Spatial differences in the heavy metal content of the soils for the whole area of Debrecen have been studied. Influence of soil properties (humus, CalciumCarbonate content, pH and grain size distribution) on the binding and mobility of heavy metals in the soil has been examined. Vertical distribution and mobility of heavy metal compounds in acid sandy soils was determined. Heavy metal content of soil in the most sensitive areas, playgrounds, recreational areas, urban gardens and grazing fields along busy roads has been surveyed.
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Development of MSW collection service on regional scale: spatial analysis and urban disparities in North-Easr Region, Romania
13-18Views:27The cities are facing illegal dumping of municipal solid waste (MSW) because the waste collection facilities do not cover the entire population. Furthermore, this sector is poorly developed in small towns or villages annexed to administrative territory units (ATU) of cities , MSW are disposed in open dumps polluting the local environment. This paper analyzes on the one hand the urban disparities on public access to waste collection services (WCS) in the North-East Region on the other hand, it performs a comparative analysis between 2003 and 2010 outlining the changes made in the context of Romania’s accession to EU. Also, it performs a quantitative assessment method of uncollected waste at urban level and correlated to demographic features of each city. Spatial-temporal analysis of waste indicators using thematic cartography or GIS techniques should be a basic tool for environmental monitoring or assessment of projects from this field in every development region (NUTS 2). The EU acquis requires the closure of noncompliant landfills, the extension of waste collection services, the development of facilities for separate collection, recycling and reuse according to waste hierarchy concept. Full coverage of urban population to waste collection services is necessary to provide a proper management of this sector. Urban disparities between counties and within counties highlights that current traditional waste management system is an environmental threat at local and regional scale.