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Biogeomorphological feedback in karst areas
101-108Views:240In the last decades, the research on ecosystem services have emerged in the field of geography. The negative impacts of human activities on the vulnerable karst areas are getting enforced quickly, which have an unfavourable influence on ecosystem service provision. On karstic areas, there are significant geographical processes, connected to biological activities. This issue is not adequately discussed in the current literature of karst ecology. In our study, we give an overview on the biogeomorphological feedbacks that change the functions and overall value of karst ecosystems.
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Mount Pele, an ecoclimatic gradient generator
27-41Views:101Generally, mountains determine the characteristics of particular areas, because of the island phenomenon they cause. However, the geological origins of mountains are multiple and they are located in different climatic regions. Nevertheless, in all aspects they reflect the basic elements of the local biologic unit. The shapes, climates, diverse water resources, biocenoses and the generated soils are the different components that determine, through their dynamic interaction, the “Mountain” ecosystem. Tectonic subduction processes lead to the development of islands such as Martinique, whose basic structure consists of a series of mountains (among them Mount Pele). Like the topographic divisions, the local micro-climates, water courses, different soils (themselves the consequences of the presence of the mountain itself) and successive volcanic eruptions determine, over time, the organization of the diverse vegetal entities.
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Spatial distribution of vegetation cover in Erbil city districts using high-resolution Pléiades satellite image
10-22Views:261Green 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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Comparison of soil moisture indices and field measurements in hilly agricultural lands of SW Hungary
50-57Views:301The retention of surface runoff and the preservation of soil moisture are among the most important water-related ecosystem services. In addition to field monitoring, advanced remote sensing techniques have been devised to reveal soil moisture dynamics on agricultural land. In our study we compare two soil moisture indices, TWI and SAVI, in three agricultural areas with different land use types. The SAVI has been found suitable to point out spatial variation on the moisture conditions of the vadose zone.
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Spatial Statistical Analysis of the relation in between population density and Human Modification of terrestrial lands at Tabia level in the Tigray Region of Ethiopia
1-9Views:199In this study first spatial pattern of the level of human modification of terrestrial lands and second its relation with population density was studied at Taiba level in the Tigray regional state of Ethiopia. For the level of human modification of terrestrial lands global Human Modification dataset (gHM) was used and for population density Gridded Population of the World, Version 4 (GPWv4.11) dataset was used. Both the data set were preprocessed before geostatistical analysis. To measure the distribution pattern Global Moran's I statistics, Cluster and Outlier Analysis (Anselin Local Morans I) statistics was used. To measure the relation between population density and human modification of terrestrial lands geographically weighted regression was used. In the case of first objective the resulting z-score of 50.50, confirm the tabias with high Human Modification of terrestrial lands are highly clustered. In case of second objective the results shows 214 Tabias containing high value and are surrounded by Tabias with high values (HH), 10 Tabias containing high value and is surrounded by Tabias with low values (HL). The relation between population density and human modification of terrestrial lands was found positive with R2= 0.506. This research will help the government and planners for proactive spatial planning to maintain biodiversity and ecosystem function before important environmental values are lost in tabias containing high value and is surrounded by Tabias with high values.
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Spatial Distribution of Heavy Metals around the Gold Mine Ore Tailings of Hatti, Karnataka State, India
35-44Views:389Mining is an imperative segment of the world economy as it contributes socio-economic status of the nations. However, developing countries like India due to lack of high profile industrial techniques and equipment, eluting effluents from the industrial process may contain various hazardous substances which greatly affect the environmental and human health. The present work is aimed with the distribution of heavy metals in and around Hatti Gold Mine Ore Tailing (H-GOT). The results elicit the mine ore tailings are having high-level contaminants of heavy metal than the crop lands of Hatti (Hs), Kotha (Ks), Chikka Nagur (Cs), Tawag (Ts), Lingsugur (Ls) of Raichur District, Karnataka. It was reported that, Hatti Gold Mine ore tailings hold about 41.31±0.49 mg/kg, 2.1±0.31mg/kg, 71.96±3.26 mg/kg, 39.56±1.47 mg/kg and 73.4±2.19 mg/kg of Arsenic (As), Cadmium (Cd), Copper (Cu), Lead (Pb) and Zinc (Zn) heavy metals respectively. While the crop lands metal contamination range depends on seasonal variation. In south-west monsoon farming lands metal contamination order is Hs> Ks>Cs> Ts >Ls, and it was decreased during Post-monsoon. This is the hallmark of the fetching huge amount of toxic heavy metals from mining center to nearest crop lands. The continuous squeezing of these toxic metals could trigger the bio-magnification in both aquatic and terrestrial ecosystem and it may impact various metabolic disorders.
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A spatio-temporal urban expansion modeling a case study Teheran metropolis, Iran
10-19Views:131During 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.