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Comparison of multisource image fusion methods and land cover classification

Journal Articles & Books
Dezembro, 2012

The aim of this study is to explore the performances of different data fusion techniques for the enhancement of urban features and evaluate the features obtained by the fusion techniques in terms of separation of urban land cover classes when multisource images are under consideration. For the data fusion, multiplicative method, Brovey transform, principal component analysis (PCA), Gram–Schmidt fusion, wavelet-based fusion and Elhers fusion are used and the results are compared.

satellite-based green index as a proxy for vegetation cover quality in a Mediterranean region

Journal Articles & Books
Dezembro, 2012
Grécia

To preserve land quality and mitigating land degradation represent an important task for regional planning and environmental management of the Mediterranean region. Since land cover dynamics directly affect the landscape characteristics, remote sensing represents an effective tool for land quality assessment at large scale.

Does large-sized cities' urbanisation predominantly degrade environmental resources in China? Relationships between urbanisation and resources in the Changjiang Delta Region

Journal Articles & Books
Dezembro, 2012
China

Outward expansion of urban lands in the developing nations is often associated with a substantial loss of environmental resources such as forests, wetlands, freshwater and cash crop fields. Yet, determining how different aspects of urbanisation – such as city population size and spread pattern of built-up lands – contribute to the cumulative loss of resources remains controversial. In this study, data sets were constructed describing changes to land cover across 65,200 grid cells at 1 km² spatial resolution for China's Changjiang Delta Region over the past 60 years.

trend of land-use sustainability around the Changbai Mountain Biosphere Reserve in northeastern China: 1977–2007

Journal Articles & Books
Dezembro, 2012
China

Extensive land-use and land-cover change, triggered by rapid development of tourism and the expansion of townships, has occurred in the area surrounding the Changbai Mountain Biosphere Reserve (CMBR) in northeast China, a reservoir for distinctive ecosystems and biological diversity. The objective of this study was to examine the land-use changes surrounding the reserve in the context of forest and nature reserve management with the aid of maps from Landsat MSS imagery of 1977 and Landsat TM imagery of 1991 and 2007.

Spatial analysis and mapping of malaria risk in an endemic area, south of Iran: A GIS based decision making for planning of control

Journal Articles & Books
Dezembro, 2012
Irã

Bashagard district is one of the important malaria endemic areas in southern Iran. From this region a total of 16,199 indigenous cases have been reported in recent years. The aim of this study was to determine the situation of the disease and provide the risk map for the area. ArcGIS9.2 was used for mapping spatial distribution of malaria incidence. Hot spots were obtained using evidence-based weighting method for transmission risk.

assessment of the effectiveness of a random forest classifier for land-cover classification

Journal Articles & Books
Dezembro, 2012
Espanha

Land cover monitoring using remotely sensed data requires robust classification methods which allow for the accurate mapping of complex land cover and land use categories. Random forest (RF) is a powerful machine learning classifier that is relatively unknown in land remote sensing and has not been evaluated thoroughly by the remote sensing community compared to more conventional pattern recognition techniques. Key advantages of RF include: their non-parametric nature; high classification accuracy; and capability to determine variable importance.

Combining the matter element model with the associated function of probability transformation for multi-source remote sensing data classification in mountainous regions

Journal Articles & Books
Dezembro, 2012
China

That the multi-source remote sensing information integrates knowledge-based geospatial constraints to develop efficient and practical Land cover classification algorithm has become one of the most important developing directions in the field of remote sensing ground object classification. Remote sensing classification is a strictly incompatible problem, but the spectra distribution of remote sensing data has compatible attributes especially in mountainous regions, and such contradiction is one of the main reasons leading to uncertainties in remote sensing classification.

Accuracy Evaluation of an ASTER-Derived Global Digital Elevation Model (GDEM) Version 1 and Version 2 for Two Sites in Western Africa

Journal Articles & Books
Dezembro, 2012
África

This study compares the ASTER Global DEM version 1 (GDEMv1) and version 2 (GDEMv2) for two study sites with distinct terrain and land cover characteristics in western Africa. The effects of land cover, slope, relief, and stack number are evaluated through both absolute and relative DEM statistical comparisons. While GDEMv2 at times performed better than GDEMv1, this improvement was not consistent, revealing the complex nature and interaction of terrain and land cover characteristics, which influences the accuracy of GDEM tiles on local and regional scales.

Winter wheat mapping using temporal signatures of MODIS vegetation index data

Journal Articles & Books
Dezembro, 2012
China

Because most land-cover types have distinct seasonal changes and corresponding reflectance characteristics in remotely sensed images, the signatures in time-series data are useful for discriminating different land covers. Although temporal signatures have been used to classify different land-cover types, they have not been fully exploited to classify specific crops, and the influence of low resolution should be evaluated.

Study on the estimation of near-surface air temperature from MODIS data by statistical methods

Journal Articles & Books
Dezembro, 2012

Spatially distributed air temperature is desired for various scientific studies, including climatalogical, hydrological, agricultural, environmental and ecological studies. In this study, empirical models with regard to land cover and spatial scale were introduced and compared to estimate air temperature from satellite-derived land surface temperature and other environmental parameters. Aqua MODIS (Moderate Resolution Imaging Spectroradiometer) data and meteorological data obtained throughout 2005 in the Yangtze River Delta were adopted to develop statistical algorithms of air temperature.

Mapping impervious surface expansion using medium-resolution satellite image time series: a case study in the Yangtze River Delta, China

Journal Articles & Books
Dezembro, 2012
China

Cities have been expanding rapidly worldwide, especially over the past few decades. Mapping the dynamic expansion of impervious surface in both space and time is essential for an improved understanding of the urbanization process, land-cover and land-use change, and their impacts on the environment. Landsat and other medium-resolution satellites provide the necessary spatial details and temporal frequency for mapping impervious surface expansion over the past four decades.