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

Journal Articles & Books
Décembre, 2012
Chine

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.

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

Journal Articles & Books
Décembre, 2012
Chine

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.

Land Cover Analysis for Urban Foresters and Municipal Planners: Examples from Iowa

Journal Articles & Books
Décembre, 2012

Contemporary land-use change and impacts on natural systems are of concern throughout the Cornbelt region, where agricultural activities have extensively altered the landscape. Land-use changes driven by urbanization throughout this region could have a disproportionate impact on remaining natural areas, particularly forests. We used readily available data sets and software to assess land cover change for four municipalities in Iowa and to examine the usefulness of this approach for urban foresters and planners interested in understanding/predicting impacts of land cover change.

Comparison of landscape patterns between metropolises and small-sized cities: a gradient analysis with changing grain size in Shanghai and Zhangjiagang, China

Journal Articles & Books
Décembre, 2012
Chine

Quantifying the urban landscape pattern and its change is fundamental for monitoring and assessing the ecological and socio-economic consequences of urbanization. Using Indian Remote Sensing Panchromatic (IRS-PAN) imagery of 2002 and combining gradient analysis with landscape metrics, we compared the landscape patterns between metropolises and small-sized cities with increasing grain size. Landscape metrics were computed along a 51 × 9 km transect cutting across Shanghai and a 16 × 2 km transect cutting across Zhangjiagang with a moving window.

Impacts of land use changes and synoptic forcing on the seasonal climate over the Pearl River Delta of China

Journal Articles & Books
Décembre, 2012
Chine

In this study, the impact of the rapid rate of urbanization over the Pearl River Delta (PRD) region of China since the 1980s on its seasonal climate is investigated using the Weather Research and Forecasting Model. Two land-cover data are employed to simulate the urbanization effects on the regional climate in both summer (June and August) and winter (December and February) for 26 years from 1984 to 2009. Spatial and temporal features of the urbanization effect on temperature and precipitation are found to be different between summer and winter.

Ecological restoration planning based on connectivity in an urban area

Journal Articles & Books
Décembre, 2012

In urban areas, the competition between land development and ecological conservation is intense. To mitigate the negative effects of urbanization, we developed a methodology to plan a spatially explicit conservation network based on widely available remotely sensed data and other auxiliary data. First, as an area of strategic significance for the conservation of regional flora and fauna and for maintaining high environmental quality to promote human well-being, the remaining natural and semi-natural areas were identified as ecologically primary areas.

Sensitivity of predicted pollutant levels to urbanization in China

Journal Articles & Books
Décembre, 2012
Chine

Urbanization in China accompanies economic development and population growth. Changes in land use leads to changes in both meteorological and chemical fields. In this study, the impact of land use change in Jing-Jin-Ji (JJJ, indicating Beijing–Tianjin–Hebei) and Yangtze River Delta (YRD) areas on meteorology and ozone concentrations are studied using the WRF–Chem model. Land use change is represented by two different land cover data sets: USGS and MODIS.

Urban sprawl impact assessment on the agricultural land in Egypt using remote sensing and GIS: a case study, Qalubiya Governorate

Journal Articles & Books
Décembre, 2012
Égypte

Urban sprawl is one of the main problems that threaten the limited highly fertile land in the Nile Delta of Egypt. In this research, satellite images of Landsat Thematic Mapper (TM) 1992, Landsat Enhanced Thematic Mapper (ETM+) 2001 and Egypt Sat-1 2009 have been used to study the urban sprawl and its impact on agricultural land in Qalubiya Governorate. Maximum likelihood supervised classification and post-classification change detection techniques were applied for monitoring the urban sprawl in this study area.

Aerosol retrieval with satellite image and correlation analyses between aerosol distribution and urban underlaying surface

Journal Articles & Books
Décembre, 2012

Human activity is one of the most important aerosol sources. Because the underlaying surface feature records most human activities, it is important to recognize the correlation between aerosol distribution and the underlaying surface.

Land use changes, landscape ecology and their socioeconomic driving forces in the Spanish Mediterranean coast (El Maresme County, 1850–2005)

Journal Articles & Books
Décembre, 2012

A set of landscape metrics is used to study the long-term environmental transformation of a typical coastal Mediterranean area from 1850 to 2005. Our figures show a dramatic environmental deterioration between 1950 and 2005. The main proximate drivers of this landscape degradation are the effects of urban sprawl on former agricultural areas located in the coastal plains, together with the abandonment and reforestation of hilly slopes intercepted by low-density residential areas, highways, and other linear infrastructures.

Changes in land use, land tenure, and landscape fragmentation in the Tijuana River Watershed following reform of the ejido sector

Journal Articles & Books
Décembre, 2012

Changes in land use and land tenure can influence both physical fragmentation and ownership fragmentation of landscapes, with implications for biodiversity. In this study, we evaluated changes in land use and land tenure in the Tijuana River Watershed, a region of high biodiversity and endemism, following the implementation of a new Agrarian Law which allowed for privatization and sales of communal land (ejidos) beginning in 1992. In order to understand changes in land use and cover, we constructed maps from aerial photographs and Aster images and measured changes between 1994 and 2005.