Measuring the urban sprawl based on economic-dominated perspective: the case of 31 municipalities and provincial capitals

Figures & data

Figure 1. Spatial distributions of 31 Chinese municipalities and provincial capitals in China.

Note: Made based on the standard map with review number GS(2016)2923 on the Ministry of Natural Resources standard map service website, with no modification to the base map.

Table 1. Introduction for data source.

Type	Name	Source	Year
Grid data	LULC data	Chinese Academy of Sciences	2005, 2010, 2015
	POP data	Chinese Academy of Sciences	2005, 2010, 2015
	GDP data	Chinese Academy of Sciences	2005, 2010, 2015
	NSL data	DMSP/OLS	2005, 2010
		NPP-VIIRS	2015
Vector data	POI data	Baidu Map	2005, 2010, 2015
	OSM data	Open Street Map	2015
	Administrative Boundary data	National Geographic Information Center of China	2015
Statistical data	China Statistical Yearbook	China Urban Statistics	2005, 2010, 2015

Figure 2. Flow chart for calculating and analyzing urban sprawl.

Figure 3. Identification of ring roads and counties, using Beijing as an example.

Figure 4. The CRC framework for analyzing urban sprawl.

Table 2. Driving indicators for urban sprawl.

Indicators	Variable name	Definition
Economy	ind2	proportion of secondary industries
	ind3	proportion of tertiary industries
	liv	per capita GDP
	com	number of buses per 10,000 people in the city
Land	pssd	standard deviation of patch areas
	psi	patch shape index

Figure 5. Maps of the variable urban sprawl, and constant in each of the 31 municipalities and provincial capitals in 2005(a), 2010(b) and 2015(c). For each map, the values are represented by colors, with the maximum values in red and the minimum values in green.

Note: Made based on the standard map with review number GS(2016)2923 on the Ministry of Natural Resources standard map service website, with no modification to the base map.

Table 3. Urban sprawl for 31 municipalities and provincial capitals.

USI	2005		2010		2015
	Number of Cities	%	Number of Cities	%	Number of Cities	%
0 to < 20	1	3	0	0	0	0
20 to < 40	20	65	1	3	19	61
40 to < 60	10	32	26	79	12	39
60 to < 80	0	0	6	18	0	0
Mean of USI	36.03		52.97		38.49
Total	31	100	31	100	31	100

Table 4. Urban sprawl for eastern municipalities and provincial capitals.

Sprawl Index	2005		2010		2015
	Number of Cities	%	Number of Cities	%	Number of Cities	%
0 to < 20	0	0	0	0	0	0
20 to < 40	8	80	0	0	6	60
40 to < 60	2	20	8	80	4	40
60 to < 80	0	0	2	20	0	0
Mean of USI	35.03		55.62		38.49
Total	10	100	10	100	31	100

Table 5. Urban sprawl for central municipalities and provincial capitals.

Sprawl Index	2005		2010		2015
	Number of Cities	%	Number of Cities	%	Number of Cities	%
0 to < 20	0	0	0	0	0	0
20 to < 40	2	33	0	0	4	67
40 to < 60	4	67	5	83	2	33
60 to < 80	0	0	1	17	0	0
Mean of USI	38.16		57.27		38.93
Total	6	100	6	100	6	100

Table 6. Urban sprawl for western municipalities and provincial capitals.

Sprawl Index	2005		2010		2015
	Number of Cities	%	Number of Cities	%	Number of Cities	%
0 to < 20	0	0	0	0	0	0
20 to < 40	8	67	0	0	7	58
40 to < 60	4	33	11	92	5	42
60 to < 80	0	0	1	8	0	0
Mean of USI	37.88		48.23		37.97
Total	12	100	12	100	12	100

Table 7. Urban sprawl for northeastern municipalities and provincial capitals.

Sprawl Index	2005		2010		2015
	Number of Cities	%	Number of Cities	%	Number of Cities	%
0 to < 20	0	0	0	0	0	0
20 to < 40	3	100	0	0	2	61
40 to < 60	0	0	1	33	1	33
60 to < 80	0	0	2	67	0	0
Mean of USI	27.66		54.52		32.98
Total	3	100	3	100	3	100

Figure 6. Maps of the USI in Beijing, Shanghai, Guangzhou, Wuhan, Chengdu, Xi’an, and Shenyang at the ring road scale.

Note: Each map represents the values using colors, with the maximum values in red and the minimum value in green; Y-coordinate represents the urban sprawl index; X-coordinate represents the ring line sequence from the inner ring to the outer ring.

Figure 7. Maps of the USI in Beijing, Shanghai, Guangzhou, Nanjing, Changsha, Tianjin, Hefei, Nanchang, and Guiyang at the county scale (Tianjin Tanggu District, Hangu District and Dagang District were merged into Binhai New Area in 2009 and are still divided into three districts for the purpose of comparison; Nanchang’s administrative divisions are constantly evolving, so use 2005 as a standard for comparison).

Note: Each map represents the values using colors, with the maximum values in red and the minimum value in green. Y-coordinate represents the urban sprawl index; X-coordinate represents the name of each county.

Table 8. Descriptive statistics for urban sprawl index and driving indicators.

	N	min	max	mean	SD
lnUSI	93	2.995	4.240	3.719	0.254
lnind2	93	2.957	4.070	3.734	0.224
lnind3	93	3.377	4.378	3.878	0.202
lnliv	93	4.574	7.659	6.185	0.692
lncom	93	0.657	3.005	1.960	0.500
lnpssd	91	3.203	6.728	4.390	0.717
lnpsi	93	0.00800	1.272	0.537	0.187

Table 9. Relationships between urban sprawl and driving indicators.

		Regions			Economic level
	Total sample	Eastern China	Central China	Western China	First- tier	Second- tier
	Model1	Model2	Model3	Model4	Model5	Model6
lnind2	−0.335*	−0.072	−0.929***	−0.487 −0.901* 0.032 −0.048 0.095* 0.251	−0.082	−0.615**
lnind3	−0.658**	0.002	−1.133**		−0.018	−1.238***
lnliv	0.043	−0.183	0.386***		0.150	0.027
lncom	0.005	0.126	0.016		−0.106	−0.014
lnpssd	0.103***	0.067	0.375***		0.068	0.184**
lnpsi	−0.004	−0.027	−0.212		−0.221	0.102
Constant term	6.598***	4.375	7.647***	8.125**	3.080**	9.577***
Obs.	91	35	27	29	42	35
Number of Cities	31	12	9	10	14	12

Data availability statement

Some data that support the results and analyses presented in this paper is publicly available from the Institute of Geographic Sciences and Resources, Chinese Academy of Sciences (http://www.resdc.cn/). The administrative boundary data including provincial and regional boundaries are publicly available from the National Geographic Information Center of China (http://ngcc.sbsm.gov.cn).