Aller au contenu principal

page search

Issuescouverture du solLandLibrary Resource
There are 2, 239 content items of different types and languages related to couverture du sol on the Land Portal.

couverture du sol

AGROVOC URI:

Displaying 1597 - 1608 of 1964

Spectral similarity-preserving hyperspectral band selection

Journal Articles & Books
Décembre, 2013

Due to the high spectral resolution, hyperspectral images (HSI) have been widely used in land cover classification and material identification. Band selection is one of the necessary preprocessings to reduce the data volume and the redundancy therein for the subsequent analysis. Aiming at speeding up the search-based band selection process, this letter proposes a new technique from the perspective of spectral curve shape similarity.

subpixel mapping algorithm combining pixel-level and subpixel-level spatial dependences with binary integer programming

Journal Articles & Books
Novembre, 2014
Global

A new subpixel mapping (SPM) algorithm combining pixel-level and subpixel-level spatial dependences is proposed in this letter. The pixel-level dependence is measured by the spatial attraction model (SAM) with either surrounding or quadrant neighbourhood, while the subpixel-level dependence is characterized by either the mean filter or the exponential weighting function. Both pixel-level and subpixel-level dependences are then fused as the weighted dependence in the constructed objective function.

Indices of bird‐habitat preference from field surveys of birds and remote sensing of land cover: a study of south‐eastern England with wider implications for conservation and biodiversity assessment

Journal Articles & Books
Décembre, 2005

Aim This paper describes the development of novel indices of bird‐habitat preference to examine bird species’ use of habitats and their distributions relative to habitats. It assesses the implications for bird conservation regionally and the scope for biodiversity assessments generally. Location A 200 km by 400 km area of farmland with seminatural and urban areas, covering south‐eastern England. Methods Cluster analysis was used to link birds to landscapes. Cluster centroid coordinate values were processed to derive indices of bird‐habitat preference.

improved automated land cover updating approach by integrating with downscaled NDVI time series data

Journal Articles & Books
Décembre, 2015

Land cover change monitoring is important for climate and environmental research. An automated approach for updating land cover maps derived from Landsat-like data is urgently needed to process large amounts of data. Change detection is an important part of the updating approach; however, pseudo-changes commonly occur because satellite images acquired in different seasons can capture phenological differences.

On the importance of non-linear relationships between landscape patterns and the sustainable provision of ecosystem services

Journal Articles & Books
Décembre, 2014
Suisse

Marginal land use changes can abruptly result in non-marginal and irreversible changes in ecosystem functioning and the economic values that the ecosystem generates. This challenges the traditional ecosystem services (ESS) mapping approach, which has often made the assumption that ESS can be mapped uniquely to land use and land cover data. Using a functional fragmentation measure, we show how landscape pattern changes might lead to changes in the delivery of ESS.

Erosion regulation as a function of human disturbances to vegetation cover: a conceptual model

Journal Articles & Books
Décembre, 2014

Human-induced land cover changes are causing important effects on the ecological services rendered by mountain ecosystems, and the number of case-studies of the impact of humans on soil erosion and sediment yield has mounted rapidly. In this paper, we present a conceptual model that allows evaluating overall changes in erosion regulation after human disturbances. The basic idea behind this model is that soil erosion mechanisms are independent of human impact, but that the frequency–magnitude distributions of erosion rates change as a response to human disturbances.

Quantifying spatial–temporal change in land-cover and carbon storage among exurban residential parcels

Journal Articles & Books
Décembre, 2014
États-Unis d'Amérique

The area of land occupied by exurban residential development is significant and has been increasing over the past several decades in the United States. Considerable attention has been drawn to the measurement of regional-scale patterns of land-cover change and assessment of its environmental and socioeconomic consequences. Yet little is known about the quantity of land-cover change within individual exurban residential parcels, which reflect homeowner preferences, land-management strategies, and the ecosystem services they generate.

Multiple scenario analyses forecasting the confounding impacts of sea level rise and tides from storm induced coastal flooding in the city of Shanghai, China

Journal Articles & Books
Décembre, 2011
Chine

Shanghai is physically and socio-economically vulnerable to accelerated sea level rise because of its low elevation, flat topography, highly developed economy and highly-dense population. In this paper, two scenarios of sea level rise and storm surge flooding along the Shanghai coast are presented by forecasting 24 (year 2030) and 44 (year 2050) years into the future and are applied to a digital elevation model to illustrate the extent to which coastal areas are susceptible to levee breach and overtopping using previously developed inflow calculating and flood routing models.

Automated cloud and shadow detection and filling using two-date Landsat imagery in the USA

Journal Articles & Books
Décembre, 2013
États-Unis d'Amérique

A simple, efficient, and practical approach for detecting cloud and shadow areas in satellite imagery and restoring them with clean pixel values has been developed. Cloud and shadow areas are detected using spectral information from the blue, shortwave infrared, and thermal infrared bands of Landsat Thematic Mapper or Enhanced Thematic Mapper Plus imagery from two dates (a target image and a reference image).

Site Suitability Analysis for Urban Development Using GIS Based Multicriteria Evaluation Technique : A Case Study of Mussoorie Municipal Area, Dehradun District, Uttarakhand, India

Journal Articles & Books
Décembre, 2013
Inde

Identification of suitable site for urban development in hilly areas is one of the critical issues of planning. Site suitability analysis has become inevitable for delineating appropriate site for various developmental initiatives, especially in the undulating terrain of the hills. The study illustrates the use of geographic information system (GIS) and multicriteria evaluation (MCE) technique for selection of suitable sites for urban development in Mussoorie municipal area, Dehradun district, Uttarakhand.

Spatio‐Temporal Patterns of Land Use/Cover Changes Over the Past 20 Years in the Middle Reaches of the Tarim River, Xinjiang, China

Journal Articles & Books
Décembre, 2015
Chine

The interaction between land use/cover change and landscape pattern is pivotal in research concerning global environmental change. This study uses three different Landsat images of 1989, 1998 and 2009 to study the land use/cover and landscape pattern changes in the middle reaches of the Tarim River basin. envi®, erdas®, ArcGIS® and fragstats® software were used to analyse the land use/cover changes. The objectives of study were to map and study the changes in land use/cover and landscape pattern, and propose some possible factors in making the land use/cover changes from 1989 to 2009.

Variogram Fractal Dimension Based Features for Hyperspectral Data Dimensionality Reduction

Journal Articles & Books
Décembre, 2013

In this paper a new approach for fractal based dimensionality reduction of hyperspectral data has been proposed. The features have been generated by multiplying variogram fractal dimension value with spectral energy. Fractal dimension bears the information related to the shape or characteristic of the spectral response curves and the spectral energy bears the information related to class separation.