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automated approach for updating land cover maps based on integrated change detection and classification methods

Journal Articles & Books
Diciembre, 2012

Updating land cover maps from remotely sensed data in a timely manner is important for many areas of scientific research. Unfortunately, traditional classification procedures are very labor intensive and subjective because of the required human interaction. Based on the strategy of updating land cover data only for the changed area, we proposed an integrated, automated approach to update land cover maps without human interaction.

Variations of urban greenness across urban structural units in Beijing, China

Journal Articles & Books
Diciembre, 2013
China

Urban structural units (USUs) are work (or similar) units in urbanized areas. In this study, USUs based on urban land use and land cover were used to explain and compare urban ecological conditions within Beijing. This study focused on the spatial pattern of land use for different USUs in urban areas. The results showed that 453 USUs belong to 12 primary USUs and to 38 different secondary USUs. The percentage of built-up area was highest in those regions with hotels, and lowest in areas with cemeteries.

Application of an evidential belief function model in landslide susceptibility mapping

Journal Articles & Books
Diciembre, 2012

The objective of this paper is to exploit the potential application of an evidential belief function model to landslide susceptibility mapping at Kuala Lumpur city and surrounding areas using geographic information system (GIS). At first, a landslide inventory map was prepared using aerial photographs, high resolution satellite images and field survey. A total 220 landslides were mapped and an inventory map was prepared. Then the landslide inventory was randomly split into a testing dataset 70% (153 landslides) and remaining 30% (67 landslides) data was used for validation purpose.

Learning with transductive SVM for semisupervised pixel classification of remote sensing imagery

Journal Articles & Books
Diciembre, 2013

Land cover classification using remotely sensed data requires robust classification methods for the accurate mapping of complex land cover area of different categories. In this regard, support vector machines (SVMs) have recently received increasing attention. However, small number of training samples remains a bottleneck to design suitable supervised classifiers. On the other hand, adequate number of unlabeled data is available in remote sensing images which can be employed as additional source of information about margins.

Evaluation of urban sprawl pattern in the tribal-dominated cities of Jharkhand state, India

Journal Articles & Books
Diciembre, 2011
India

The patterns of urban sprawl over a 20-year period presented in the study indicate unplanned development in the urban agglomerations of Ranchi, Jamshedpur and Dhanbad. The visual interpretation of Landsat (1986, 1991, 1996 and 2001) and IRS-P6 (2005) was used to map land use/land cover and analyse urban sprawl. The saturation of urban areas within municipal limits, along with pressure from the growing population, resulted in the densification of the core urban areas within Dhanbad and Jamshedpur.

Mapping technological and biophysical capacities of watersheds to regulate floods

Journal Articles & Books
Diciembre, 2016
Estados Unidos de América

Flood regulation is a widely valued and studied service provided by watersheds. Flood regulation benefits people directly by decreasing the socio-economic costs of flooding and indirectly by its positive impacts on cultural (e.g., fishing) and provisioning (e.g., water supply) ecosystem services. Like other regulating ecosystem services (e.g., pollination, water purification), flood regulation is often enhanced or replaced by technology, but the relative efficacy of natural versus technological features in controlling floods has scarcely been examined.

Space and time dynamics of urban water demand in Portland, Oregon and Phoenix, Arizona

Journal Articles & Books
Diciembre, 2015

Critical to effective urban climate adaptation is a clearer understanding of the sensitivities of resource demand to changing climatic conditions and land cover situations. We used Bayesian Maximum Entropy (BME) stochastic procedures to estimate temperature and precipitation at the very small scale of urban Census Block Groups (CBGs) in Phoenix, Arizona and Portland, Oregon, and then compared average household water use patterns by climate conditions and land cover characteristics between and within the two cities.

Land-use land-cover change and ecosystem loss in the Espinal ecoregion, Argentina

Journal Articles & Books
Diciembre, 2013
Argentina

Land-use land-cover (LULC) changes are one of the major threats to biodiversity worldwide, since their principal consequences are the loss, fragmentation or degradation of the habitat available for most species. Therefore, in order to provide guidelines for environmental management at the regional scale and thus reverse the trend in degradation, transformations of natural remnants into anthropogenic land uses must be identified and quantified.

Radar analysis of fall bird migration stopover sites in the northeastern U.S

Journal Articles & Books
Diciembre, 2014

The national network of weather surveillance radars (WSR-88D) detects flying birds and is a useful remote-sensing tool for ornithological study. We used data collected during fall 2008 and 2009 by 16 WSR-88D radars in the northeastern U.S. to quantify the spatial distribution of landbirds during migratory stopover. We geo-referenced estimates based on radar reflectivity, of the density of migrants aloft at their abrupt evening exodus from daytime stopover sites, to the approximate locations from which they emerged.

Unsupervised and supervised classification of hyperspectral imaging data using projection pursuit and Markov random field segmentation

Journal Articles & Books
Diciembre, 2012

This work presents a classification technique for hyperspectral image analysis when concurrent ground truth is either unavailable or available. The method adopts a principal component analysis (PCA)-based projection pursuit (PP) procedure with an entropy index for dimensionality reduction, followed by a Markov random field (MRF) model-based segmentation. An ordinal optimization approach to PP determines a set of ‘good enough projections’ with high probability, the best among which is chosen with the help of MRF model-based segmentation.

Agricultural expansion: land use shell game in the U.S. Northern Plains

Journal Articles & Books
Diciembre, 2014
Estados Unidos de América

Land area planted to row crops has expanded globally with increased demand for food and biofuels. Agricultural expansion in the Dakota Prairie Pothole Region (DPPR), USA affects a variety of agricultural and non-agricultural land-use types, including grasslands and wetlands that provide critical wildlife habitat and other ecosystem services. The purpose of this study was to quantify recent changes in rural land cover/land use, analyze trends, and interpret results in relation to climate, agronomic practice, and ethanol production.

Relationships between land cover and the surface urban heat island: seasonal variability and effects of spatial and thematic resolution of land cover data on predicting land surface temperatures

Journal Articles & Books
Diciembre, 2014

We investigated the seasonal variability of the relationships between land surface temperature (LST) and land use/land cover (LULC) variables, and how the spatial and thematic resolutions of LULC variables affect these relationships. We derived LST data from Landsat-7 Enhanced Thematic Mapper (ETM+) images acquired from four different seasons.