1. Urban expanding process along the transport corridor and the policy framework in Nanjing, China Chen Shuang, Sophia Nanjing Institute of Geography and Limnology, Chinese Academy of Sciencies Email: schens@niglas.ac.cn

2. 2007, HKBU Introduction During the past two decades, cities in the Yangtze River Delta have undergone rapid spatial expansion in relation with economic progress and population concentration in this area. The fast urban growth diminishes arable lands and ecological habitats as well as generating damaging effects through such sources as pollution and human use. Urban processes must be studied in order to understand their influences and minimize the negative effects on surrounding environment.

3. 2007, HKBU Preliminary hypothesis The urban area generally extends from the centre outward with the form like a fried-egg. The expansion process is presumed to follow the cycled phases of expansion along transport corridors and filling space between the corridors. Rather than land price, policies and residential or firms’ preferences determine land development and land allocation due to the municipal government’s monopolisation of land supply in Chinese cities. Gu et al., 2000

4. 2007, HKBU Objectives Quantitatively describe urban expansion process; Investigate trends in land development patterns; Determine to what extent the land policy and planning affect land development.

5. 2007, HKBU Urban expansion of Nanjing 1986 Build-up area 1996 Build-up area 2002 Build-up area Vegetation water Area (km 2 ) Population (person) Population density (persons per km 2 ) GDP per person (US dollar) Nanjing65825,836,0008874130

6. 2007, HKBU Urban Nanjing image 2005 仙林 Xianlin new town 东山 Dongshan new town 浦口 - 珠江 Pukou-Zhujiang new town

7. 2007, HKBU Location of study area South siteNorth site DelineationAlong the airport highway lasting about 27 km from the city wall, 3 km buffer from the way Along the Nanjing-Luhe freeway lasting about 27 km from the Yangtze River, 3 km buffer from the way Area167 km 2 160 km 2 AdministrationYuhua District Jiangning District (formerl Jiangning county) Pukou district Luhe district (original Dachang district) Land / planning management District government Municipal government

8. 2007, HKBU Index and data sources Description indicatorDefinitionData sources Urban intensity (UI)Developed urban area / total area1986, 1996, 2002 Land use data in shape file interpreted from TM images of Nanjing; 2005 Sport 4 satellite image of Nanjing; 1:50000 topographic map of Nanjing; Satellite Image Atlas of Nanjing, 2005; Urban master plan of Nanjing 1981-2000; Urban master plan of Nanjing 1991-2010; Urban master plans of Pukou, Luhe, Dongshan 2002-2020 Urban expansion speed (UES)Developed area in a period / years Land development structure (LDS)Ratio of residential, public service, industrial etc. land use types to the total developed urban area Land use efficiency (LUE)Built-up area / the total area of developed land Urban expansion track (UET)A series of gravity centre of developed land parcels in different periods. Mean area of newly developed land parcels (MANDL) Mean area of developed land parcels in a period Adherence of newly developed land parcel to the built-up area (ANDL) The mean value of developed land parcels’ nearest distance to the built-up area in a period.

9. 2007, HKBU Changes of UI and UES The urban area extended at a faster speed in the two sites comparing with that in the whole city, indicating development concentration along the transport corridors. The expansion speed was accelerated from 1996-2002 both for the south site and the whole city. Nanjing city

10. 2007, HKBU Land development structure South siteNorth site For the developed land parcels in the three periods, residential/service land use occupied about 30-70%, industrial land use occupied about 10-50%, and the other was mixed land use and unused land. Industrial development within 1996-2002 and campus development within 2002-2005 were the major approach to urban expansion besides residential development.

11. 2007, HKBU Land use efficiency A lot of land has not been used in the developed parcels during the fast expansion period. The efficiency decreased from over 96% to about 68%. The rapid expansion in the south site is attributed to land enclosure to some extent.

12. 2007, HKBU Landscape indicators South siteNorth site 86-9696-0202-0586-9696-0202-05 MANDL (hectare) 66.9773.5918.5956.1318.5218.04 ANDL (m) Mean379.33661.1488.2679.8938.7655.47 Max 1940.313525.481115.211288.91761.183841.724 Min 00 0 00 0 The area of land parcels tend to be smaller pieces and the distance to built up area tend to be shorter in relation to adoption of compact development pattern. For the two sites the land parcel was located within 3.5 km to the built up area.

13. 2007, HKBU Urban expansion track Campus Industrial Residential South siteNorth site 86-96 96-02 02-05 86-96 96-02 02-05 86-96 96-02 02-05 96-02 86-96 02-05 96-02 86-96 02-05 96-02 86-96

14. 2007, HKBU Trends of land development patterns The expansion speed tend to slow down after the irrationally quick urban development within 1996-2002 according to the UI and UES changes. Residential and public service including campus development have been becoming the major approach of urban expansion by the analysis of land use structure. The compact land development pattern tend to come back based on the land use efficiency calculation and the landscape indicator analysis.

15. 2007, HKBU Effect of planning on land development Comparison of practical land allocation to the planning 80-98% of the two sites was not covered by the master urban plan within the fast expansion period. About 50% of the development covered by the plan differed in land use type. The coherence frequency tended to be improved.

16. 2007, HKBU Effect of policy on land development pattern Differences in development pattern between the two sites with variant management systems South site (1986-2005)North site (1986-2005) Management system Local decision-making in planning and land supply Municipal decision-making in planning and land supply Speed3.30 km/yr1.68 km/yr Structure The portion of campus land have been increasing and that of residential land decreasing. The portion of residential land have been increasing Efficiency of land use80.18%89.36% Landscape Messed layout, each type of land use parcels equally distributed at two sides of the transport line Cluster layout, each type of land use parcels relatively concentrated and the homogenous clusters scattered in the site PlanningLow efficiencyEffective

17. 2007, HKBU Conclusion The high resolution satellite images provide abundant data for quantitatively analysis of urban expansion process in China. The research on quantitative description of urban expansion and its driving forces is important and realizable. The local government largely influenced urban land development but the decision maker are short of relevant supporting knowledge of land allocation. Residential/firms preferences for transport or amenity would be studied later quantitatively.

18. 2007, HKBU The End and Thanks!