A GIS-based gradient analysis of urban landscape

(整期优先)网络出版时间:2019-02-25
/ 1
Quantifying landscape pattern and its change is essential for the monitoring and assessment of ecological consequences of
urbanization. As the largest city in the country,metropolitan Shanghai is nowthe fastest growing area among all major Chinese
cities with more than 13 million residents. Using the GIS-based land use data set of the year 1994 and combining gradient
analysis with landscape metrics, we attempted to quantify the spatial pattern of urbanization in the Shanghai metropolitan
area. The results of transect analysis with class-levelmetrics showed that the spatial pattern of urbanization could be quantified
reliably using landscape metrics and different land use types exhibited distinctive, but not necessarily unique, spatial signatures.
The results of transect analysis with landscape-level metrics showed that urbanization in the metropolitan Shanghai region
has resulted in dramatic increases in patch density (PD), edge density (ED), and patch and landscape shape complexity, and
sharp decreases in the largest and mean patch size (MPS), agriculture land use type, and landscape connectivity. The general
pattern of urbanization was that the increasingly urbanized landscape became compositionally more perse, geometrically
more complex, and ecologically more fragmented. In addition, our results supported the hypotheses that, with increasing
urbanization, patch density increases while patch size and landscape connectivity decrease. However, our results on patch
shape seemed to reject the hypothesis that patch shape becomes more regular as human modification to landscapes intensifies.
© 2003 Elsevier B.V. All rights reserved.
关键字:Urbanization; Gradient analysis; Landscape metrics; Landscape pattern; Metropolitan Shanghai