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Application of Google Maps API service for creating web map of information retrieved from CORINE land cover databases  [PDF]
Kilibarda Milan,Proti? Dragutin,Nestorov Ivan
Glasnik Srpskog Geografskog Dru?tva , 2010, DOI: 10.2298/gsgd1004103k
Abstract: Today, Google Maps API application based on Ajax technology as standard web service; facilitate users with publication interactive web maps, thus opening new possibilities in relation to the classical analogue maps. CORINE land cover databases are recognized as the fundamental reference data sets for numerious spatial analysis. The theoretical and applicable aspects of Google Maps API cartographic service are considered on the case of creating web map of change in urban areas in Belgrade and surround from 2000. to 2006. year, obtained from CORINE databases.
A Land Cover Separability Analysis on Aerial Digital Images  [cached]
Roxana Olaru
DOCT-US , 2009,
Abstract: The ground level analysis of land cover, though very accurate, has a punctual character and the observations are difficult to extrapolate to broad scale extent. The Corine Land Cover European program used low and medium spatial resolution satellite images to discern between different land uses and land covers, mapping these areas within a European database. The use of high sensitivity airborne sensors lowered the level of analysis and offered capabilities for small scale mapping of different reflective surfaces. The LPIS National Program (Land Parcel Identification System) offers the possibility of land cover/use analysis on a national level for the year 2005 (year of the flight). The issues that have to be considered in the automatic analysis of these images are related to the different seasons of the image taking and different sensors involved. The paper proposes to perform an analysis of the spectral response in the visible part of the electromagnetic spectrum. The analysis shows low separability of the different vegetation classes, especially in the forested areas (the infrared band is not taken into account). The study shows a good separation of the artificial lands, especially settlements, arable land and orchards. Additional information can be processed using interactive photointerpretation of the images.
Land-cover classification with an expert classification algorithm using digital aerial photographs
Alberto J. Perea,José E. Mero?o,María J. Aguilera,José L. de la Cruz
South African Journal of Science , 2010, DOI: 10.4102/sajs.v106i5/6.237
Abstract: The purpose of this study was to evaluate the usefulness of the spectral information of digital aerial sensors in determining land-cover classification using new digital techniques. The land covers that have been evaluated are the following, (1) bare soil, (2) cereals, including maize (Zea mays L.), oats (Avena sativa L.), rye (Secale cereale L.), wheat (Triticum aestivum L.) and barley (Hordeun vulgare L.), (3) high protein crops, such as peas (Pisum sativum L.) and beans (Vicia faba L.), (4) alfalfa (Medicago sativa L.), (5) woodlands and scrublands, including holly oak (Quercus ilex L.) and common retama (Retama sphaerocarpa L.), (6) urban soil, (7) olive groves (Olea europaea L.) and (8) burnt crop stubble. The best result was obtained using an expert classification algorithm, achieving a reliability rate of 95%. This result showed that the images of digital airborne sensors hold considerable promise for the future in the field of digital classifications because these images contain valuable information that takes advantage of the geometric viewpoint. Moreover, new classification techniques reduce problems encountered using high-resolution images; while reliabilities are achieved that are better than those achieved with traditional methods.
Mapping Mountain Front Recharge Areas in Arid Watersheds Based on a Digital Elevation Model and Land Cover Types  [PDF]
E. E. Bowen, Y. Hamada, B. L. O’Connor
Journal of Water Resource and Protection (JWARP) , 2014, DOI: 10.4236/jwarp.2014.68072
Abstract:

A recent assessment that quantified potential impacts of solar energy development on water resources in the southwestern United States necessitated the development of a methodology to identify locations of mountain front recharge (MFR) in order to guide land development decisions. A spatially explicit, slope-based algorithm was created to delineate MFR zones in 17 arid, mountainous watersheds using elevation and land cover data. Slopes were calculated from elevation data and grouped into 100 classes using iterative self-organizing classification. Candidate MFR zones were identified based on slope classes that were consistent with MFR. Land cover types that were inconsistent with groundwater recharge were excluded from the candidate areas to determine the final MFR zones. No MFR reference maps exist for comparison with the study’s results, so the reliability of the resulting MFR zone maps was evaluated qualitatively using slope, surficial geology, soil, and land cover datasets. MFR zones ranged from 74 km2 to 1547 km2 and accounted for 40% of the total watershed area studied. Slopes and surficial geologic materials that were present in the MFR zones were consistent with conditions at the mountain front, while soils and land cover that were present would generally promote groundwater recharge. Visual inspection of the MFR zone maps also confirmed the presence of well-recognized alluvial fan features in several study watersheds. While qualitative evaluation suggested that the algorithm reliably delineated MFR zones in most watersheds overall, the algorithm was better suited for application in watersheds that had characteristic Basin and Range topography and relatively flat basin floors than areas without these characteristics. Because the algorithm performed well to reliably delineate the spatial distribution of MFR, it would allow researchers to quantify aspects of the hydrologic processes associated with MFR and help local land resource managers to consider protection of critical groundwater recharge regions in their development decisions.

A study on environmental background of East Asian land cover using digital terrain models
东亚土地覆盖环境背景数字地面模型研究

XIANG Bao,LIU Ji-yuan,ZHANG Zeng-xiang,
香宝
,刘纪远,张增祥

地理研究 , 2001,
Abstract: Based on methods of geographical information system and remote sensing technology, the single element's thematic digital terrain models of the elevation, aspect, slope, temperature, precipitation, maximum potential evapotranspiration, moistureand NDVI, which areintimately related to land cover environmental background in East Asia, are studied under unifiedprojection, unifiedspatial resolution and unifiedcoordination system, respectively. Then all the single elements are integrated to generate synthetic digital terrain models containing characteristics of each element by using Principle Component Analysis method. Finally, the characteristics of environmental background of land cover in East Asia reflected by the synthetic digital terrain model are analyzed. The characteristics of environmental background of land cover in East Asia are as follows: (1)The environmental background of land cover in East Asia has regularities of extention from northeast to southwest and gradation of southeast to northwest. At the same time, the distribution range of this characteristic is consistent with the range of monsoon climate area. We also found the zonal distribution of environmental background in western edge of this region is very complex. These phenomena completely incarnate the complexityof topography and climate in this area. (2)In the monsoon climate area, there exists not only the regularities of longitudinal zonality, characterized by extention from northeast to southwestand gradation from southeast to northwest, but also the regularitiesof latitudinal zonality featured by extention from east to west and gradationfrom north to south. (3)In northwest inland area including Xinjiang, northwestern part of Qinghai-xizang Plateau, western part of Inner Mongolia and southwestern part of Mongolia, a broad sense of eastern part of central Asia dominated by mountainsand basins in topography, the southeast monsoon, temperate westerly and Arctic Ocean air currents are inaccessible to reach this area, so the quality of environmental background of land cover in this area is very low. (4)In northern part of East Asia, because of flat terrain endowed with certain amount of precipitation compared with northwest inland area,the land cover environmental background condition is relatively high and has the longitudinal zonality of extention from east to west and gradationfrom south to north.
Detection and Mapping of Land Use and Land Cover Classes of a Developing City in Southeastern Region of Nigeria, using Multi-band Digital Remotely-sensed Data
JD Njoku, TE Ebe, EC Pat-Mbano
African Research Review , 2010,
Abstract: Land use and land cover dynamics has been commonplace around Owerri and environs. Landsat TM 86 and ETM+ 2000 were used to detect and map these changes. The imageries were mapped at the scales of 1:250,000 and 1:150,000 using ILWIS Academic 3.0 GIS software. The result showed significant shift in the aggregate land use and land cover class due to natural and anthropogenic forcing agents. Forest vegetation class had the largest coverage on the land use and land cover maps of 1986 and 2000. The bare/eroded surfaces class gave the highest PAVM value of 65.7% followed by water body of 44.9%. This implies that the LU and LC underwent massive transformation and change in the period of study. These types of LU and LC and the spate of dynamics must be considered in the preparation of development plans for cities in the region.
Digital preservation in Slovenia: an overview  [PDF]
Alenka Kav?i?-?oli?
Knji?nica : Revija za Podro?je Bibliotekarstva in Informacijske Znanosti , 2011,
Abstract: Digital preservation has been gaining its significance mostly because of the exponential growth of digital resources, which should be understood in the framework of the information technology and society development. As a consequence, many of national and international policy and strategy initiatives which foster the development of preservation of digital heritage are taking rise. An overview of digital preservation in Slovenia from the library science perspective is presented, and the comparison with archival approach is discussed. According to the Slovenian Deposit Law, the National and University Library (NUK) is the only library responsible for digital preservation of electronic publications. Due to the lack of staff and financial resources NUK has started with this practice some years later than other developed libraries all over the world.In the SWOT analysis some advantages and opportunities are described. It was concluded that optimal results can only be achieved by cooperation of relevant institutions.
High Spatial Resolution Land Cover Mapping Using Remotely Sensed Image  [cached]
H. S. Lim,M. Z. MatJafri,K. Abdullah
Modern Applied Science , 2009, DOI: 10.5539/mas.v3n5p82
Abstract: Land cover classification from remotely sensed data is an important topic in remote sensing applications. This paper present an economical analysis of land covers in Mebok Estuary, Penang, Malaysia. This study investigated the potential of using digital camera for land cover mapping Mebok Estuary, Penang, Malaysia. Airborne digital imagery has proved to be an effective tool for land cover studies. A Kodak camera, model DC290, was used to capture images from an elevation of 2438.4 meter on board Cessna 172Q. The use of digital camera as a sensor to capture digital images is cheaper and economical compared to the use of other airborne sensor. This technique overcomes the problem of the difficulty in obtaining cloud-free scenes in the Equatorial region from a satellite platform. Supervised classification techniques were used in the classification analysis. Supervised classification technique (Parallelepiped with Maximum Likelihood as tie breaker classifier, PML, Maximum Likelihood, ML, Minimum Distance-to-Mean, MDM, and Parallelepiped, P) was applied to the digital camera spectral bands (red, green and blue) to extract the thematic information from the acquired scenes. The best supervised classifier was chosen based on the highest overall accuracy and Kappa statistic. The accuracy of the classified images was validated using a reference data set. The study revealed that the Parallelepiped with Maximum Likelihood as tie breaker classifier produced superior result and achieved a high degree of accuracy. The classified land cover map was geometrically corrected to provide a geocode map. The results produced by this study indicated that land cover features could be clearly identified and classified into a land cover map. This study suggested that the land cover types of Mebok Estuary, Penang, Malaysia can be accurately mapped.
A spatial resolution threshold of land cover in estimating terrestrial carbon sequestration in four counties in Georgia and Alabama, USA
S. Q. Zhao, S. Liu, Z. Li,T. L. Sohl
Biogeosciences (BG) & Discussions (BGD) , 2010,
Abstract: Changes in carbon density (i.e., carbon stock per unit area) and land cover greatly affect carbon sequestration. Previous studies have shown that land cover change detection strongly depends on spatial scale. However, the influence of the spatial resolution of land cover change information on the estimated terrestrial carbon sequestration is not known. Here, we quantified and evaluated the impact of land cover change databases at various spatial resolutions (250 m, 500 m, 1 km, 2 km, and 4 km) on the magnitude and spatial patterns of regional carbon sequestration in four counties in Georgia and Alabama using the General Ensemble biogeochemical Modeling System (GEMS). Results indicated a threshold of 1 km in the land cover change databases and in the estimated regional terrestrial carbon sequestration. Beyond this threshold, significant biases occurred in the estimation of terrestrial carbon sequestration, its interannual variability, and spatial patterns. In addition, the overriding impact of interannual climate variability on the temporal change of regional carbon sequestration was unrealistically overshadowed by the impact of land cover change beyond the threshold. The implications of these findings directly challenge current continental- to global-scale carbon modeling efforts relying on information at coarse spatial resolution without incorporating fine-scale land cover dynamics.
A spatial resolution threshold of land cover in estimating regional terrestrial carbon sequestration  [PDF]
S. Zhao,S. Liu,Z. Li,T. L. Sohl
Biogeosciences Discussions , 2009,
Abstract: Changes in carbon density (i.e., carbon stock per unit area) and land cover greatly affect carbon sequestration. Previous studies have shown that land cover change detection strongly depends on spatial scale. However, the influence of the spatial resolution of land cover change information on the estimated terrestrial carbon sequestration is not known. Here, we quantified and evaluated the impact of land cover change databases at various spatial resolutions (250 m, 500 m, 1 km, 2 km, and 4 km) on the magnitude and spatial patterns of regional carbon sequestration in the southeastern United States using the General Ensemble biogeochemical Modeling System (GEMS). Results indicated a threshold of 1 km in the land cover change databases and in the estimated regional terrestrial carbon sequestration. Beyond this threshold, significant biases occurred in the estimation of terrestrial carbon sequestration, its interannual variability, and spatial patterns. In addition, the overriding impact of interannual climate variability on the temporal change of regional carbon sequestration was unrealistically overshadowed by the impact of land cover change beyond the threshold. The implications of these findings directly challenge current continental- to global-scale carbon modeling efforts relying on information at coarse spatial resolution without incorporating fine-scale land cover dynamics.
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