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Issueszone urbaineLandLibrary Resource
Displaying 1273 - 1284 of 1963

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

Journal Articles & Books
Décembre, 2013
Chine

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.

Mapping technological and biophysical capacities of watersheds to regulate floods

Journal Articles & Books
Décembre, 2016
États-Unis d'Amérique

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.

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

Journal Articles & Books
Décembre, 2011
Inde

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.

Determination effects of impervious areas on urban watershed

Journal Articles & Books
Décembre, 2015
Turquie
États-Unis d'Amérique

After the industrial revolution, urban growth has been increasing, especially with technological advances. Urbanization is accelerating environmental pollution and also affects climate significantly because of land use or land cover changes. In this study, the Hydrological Simulation Program-Fortran (HSPF) model developed by the United States Environment Protection Agency (USEPA) is used for modeling the impervious areas of Eskişehir which is located in the Porsuk Stream Watershed in Inner Anatolia, Turkey.

Classifying a high resolution image of an urban area using super-object information

Journal Articles & Books
Décembre, 2013

In this study, a multi-scale approach was used for classifying land cover in a high resolution image of an urban area. Pixels and image segments were assigned the spectral, texture, size, and shape information of their super-objects (i.e. the segments that they are located within) from coarser segmentations of the same scene, and this set of super-object information was used as additional input data for image classification.

Avian diversity in a suburban park system: current conditions and strategies for dealing with anticipated change

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

A growing trend towards increased urbanization emphasizes the role of suburban parks in wildlife conservation. Spatial planning aimed at maintaining biological diversity and functionality must consider how changes at landscape and more local scales will influence the biotic structure of urban areas. From May 2006 to July 2010, bird surveys were conducted in three metropolitan parks in Cleveland, Ohio, USA.

Demographic consequences of climate change and land cover help explain a history of extirpations and range contraction in a declining snake species

Journal Articles & Books
Décembre, 2014

Developing conservation strategies for threatened species increasingly requires understanding vulnerabilities to climate change, in terms of both demographic sensitivities to climatic and other environmental factors, and exposure to variability in those factors over time and space. We conducted a range‐wide, spatially explicit climate change vulnerability assessment for Eastern Massasauga (Sistrurus catenatus), a declining endemic species in a region showing strong environmental change.

Heavy Metal Pollution in Urban Soil from 1994 to 2012 in Kaifeng City, China

Journal Articles & Books
Décembre, 2016
Chine

Heavy metal pollution in urban soil has become a serious environmental issue in China since the last three decades. Attention has been given to the investigation of soil contamination; however, there is little information available on the variation of heavy metal pollution in soils. To resolve this problem and provide references on similar regions, 18 topsoil (0∼20 cm) samples were collected from identical sites of districts that with different functions in Kaifeng City in 1994 and 2012. Total contents of As, Cd, Hg, and Pb were determined by standard methods.

Assessing the impact of urbanization on net primary productivity using multi-scale remote sensing data: a case study of Xuzhou, China

Journal Articles & Books
Décembre, 2015
Chine

An improved Carnegie Ames Stanford Approach (CASA) model based on two kinds of remote sensing (RS) data, Landsat Enhanced Thematic Mapper Plus (ETM +) and Moderate Resolution Imaging Spectro-radiometer (MODIS), and climate variables were applied to estimate the Net Primary Productivity (NPP) of Xuzhou in June of each year from 2001 to 2010. The NPP of the study area decreased as the spatial scale increased. The average NPP of terrestrial vegetation in Xuzhou showed a decreasing trend in recent years, likely due to changes in climate and environment.