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China has experienced and is experiencing expeditious urban expansion in the recent decades, especially in the coastal areas and big cities. Rapid urban expansion and dramatic changes of landscape have caused great economic, environmental and social impacts consequently. It is crucial to understand urban temporal, spatial expansion patterns and their related effects. In this paper, urban expansion of Guangzhou, a rapid growing city in south-east China, from 1979 to 2003 is studied temporally and spatially. Four time ranges including 1979-1990, 1990-1995, 1995-2000 and 2000-2003 are designed and the urban expansion area, expansion rate and the spatial expansion pattern are discussed by using remote sensing data and Geographical Information System (GIS) tool. Two transects are designed along two axes of Guangzhou expansion and the structural of urban expansion patches at different orientations are compared in order to quantitively understand the urban expansion of Guangzhou during the past 24 years. The gradient analysis integrating multi-temporal data is performed in order to analyze and compare the spatial and temporal dynamics of urban expansion. Two indices of compactness and fractal dimensional index are used to describe the urban developing pattern in the study time durations. And the influence of different types of traffic roads to urban expansion is evaluated using the buffer analysis of GIS. The results show that: (1) temporally, urban area of Guangzhou increase 296.54 km2 from 141.15 km2 in 1979 to 437.70 km2 in 2003 and the increasing rate is up to 210.08%; (2) spatially, Guangzhou has different urban expanding directions in different stages and the general expanding directions are towards northeast, north, southeast and north in four studied time ranges; (3) transportation lines play a very important role in urban expansion of Guangzhou, but different types of road have different impacts. National roads and highways exhibit stronger control to urban expansion than provincial roads; and (4) expansion of Guangzhou has gradually changed from a compact pattern to leapfrogging and disordering patterns. [ABSTRACT FROM AUTHOR]

The landscape pattern of Daqing city, China has undergone a significant change in 1990–2000 as a result of the rapid urbanization process. The focus of this paper is to quantitatively capture landscape pattern and its spatial dynamics of Daqing city at the landscape level over the 10 years span. A traditional supervised classification (maximum likelihood classification) was carried out on Daqing region using three sets of Landsat Thematic Mapper (TM) imagery, respectively acquired in 1990. 1996. and 2000, and the classification results were transformed to polygon layers and input into geographic information system (GIS) software. In order to facilitate our examination of landscape pattern and its dynamics in Daqing, we chose two categories of landscape indices with supplementary ecological meanings. They are patch-based indices and spatial heterogeneity-based indices. Specifically, for the first category, three representative indices (Patch size coefficient variation, Landscape shape index, and Area-weighted mean patch fractal dimension) were calculated. For the latter category, Shannon's diversity index, Contagion index, Proximity index, and Fragment index were chosen and computed. Based on the derived indices, a general trend of landscape change was revealed: wetland was degraded into grassland resulting in a more fragmented pattern, whereas grassland was cultivated and taken over by agriculture. Forest coverage decreased with the small patch replaced by grassland and agriculture, while city was sprawling by merging neighbouring land cover and land use types. GIS-based landscape index, coupled with remote sensing analysis, proved its unique value and effectiveness in assessing landscape pattern and dynamics. [ABSTRACT FROM AUTHOR]

The Zhujiang Delta of South China has experienced a rapid urban expansion over the past two decades due to accelerated economic growth. This paper reports an investigation into the application of the integration of remote sensing and geographic information systems (GIS) for detecting urban growth and assessing its impact on surface temperature in the region. Remote sensing techniques were used to carry out land use/cover change detection by using multitemporal Landsat Thematic Mapper data. Urban growth patterns were analysed by using a GIS-based modelling approach. The integration of remote sensing and GIS was further applied to examine the impact of urban growth on surface temperatures. The results revealed a notable and uneven urban growth in the study area. This urban development had raised surface radiant temperature by 13.01 K in the urbanized area. The integration of remote sensing and GIS was found to be effective in monitoring and analysing urban growth patterns, and in evaluating urbanization impact on surface temperature. [ABSTRACT FROM AUTHOR]