Sustainable City Development Measurement Based on Gridded Inclusive Wealth— — a comparison between Japan and China**○Bingqi Zhang * ・ 若 松 美 保 子 ・ 馬 奈 木 俊 介 † †１ ． Introduction
In view of the increasing complexity of city problems, Inclusive Wealth (IW) has been used tomeasure urban sustainability due to its comprehensiveness. The whole city is usually regarded asa single assessment unit in such researches. However, the distribution of IW and the three capitalsof IW, human capital (HC), produced capital (PC) and natural capital (NC) are significantlydifferent between urban centers and the suburb areas. To explore the capital connection between
urban centers and their surrounding suburbs and its change could help us understand theurbanization mechanism and make better decisions on sustainable city design and urban planning.
With the proper geographical technologies and ancillary data, the gridded IW data can becreated for the analysis of spatial distributio n. However, it is tricky to create co mparable gridded IW
maps between two years because of the nonconsistency of the ancillary geographical data.

To address the two issues above, this research first created comparable gridded IW data for theyear of 2010 and 2017 by a series of examination and calibration on the original ancillary data.
Then we took China and J apan as examples to analyze the difference in the urbanization process
between developed and developing countries.
２ ． Data and Methodology
For HC, we first calculated the per capita HC for each city in China and Japan in 2010 and2017. Then we obtained the gridded population data f rom WorldPop and adjusted them to makesure that the sum of gridded population within a city is equal to the corresponding number
reported by the statistical bureau. Finally, we multiplied per capita HC with the adjusted gridded
population and got the gridded HC data.
For PC, we assume that produced capital has a positive linear relationship with the nighttime
luminosity in urban areas. Because the nighttime light data of 2010 and 2017 come from different
satellites, we performed a cross-sensor calibration to make them comparable. The PC wealth at
the city level was disaggregated to each grid in proportion to the digital number of each pixel inthe calibrated nighttime light imageries.
For NC, we followed the method of non-timber valuation in Inclusive Wealth Report 2018 to*

九 州 大 学 大 学 院 工 学 研 究 院 Department of Engineering, Kyushu University〒 819-0395**††

福 岡 市 西 区 元 岡 744

九州大学大学院工学研究院
九州大学都市研究センター

TE L& FAX 09-2802-2 735

E -mai l:sa ra zbq1226 @gm ail.c om

estimate the wealth of renewable resources. For the non-renewable resources, we allocated thenational wealth of each resource to where they deposit according to their distribution maps.
３ ． Results
The IW density of China increases by 67.4% from 13.2 in 2010 to 22.2 million USD/km 2 in2017. The IW density of Japan only increased by 6.8% from 133.8 to 142.1 million USD/km 2 .
For the 345 cities in China, all the cities experience an increase in HC. PC increases fastest
especially for the western cities in Xinjiang and Tibet. Only few cities in middle China areenjoying an increase in NC. For Japan, HC in major cities like Tokyo are increasing, while manyrural cities are suffering a serious depopulation problem. What is interesting is that most of thosecities with declining HC have an increasing manufacturing capital. Most NC-declining cities
appears in metropolitan areas.
Fig.1 shows the IW growth patterns in two biggest cities of each country. The IW distributions
in Tokyo and Osaka don’t change much, but there is a clear increase in Beijing and Shanghai.

Fi g.1 G ri d d ed i n clu s i ve w ea lt h ch an ge i n met rop o li s es from 2 0 1 0 t o 2 0 1 7

４ ． Conclusion
Rather than the gridded IW calculation for a single year, this research shows the change of IW
between 2010 and 2017, which indicates regional sustainability. The results of this study wellreveal the difference between developed and developing regions in terms of human, manufacturaland environmental aspects. HC and PC are increasing at the cost of natural resources, and PC
increases fastest in developing countries; in developed countries, the depopulation in rural areas
exacerbates the inequality of HC distribution, NC increases possibly because of the improvementof people’s environmental consciousness. Wealth expansion from urban centers to its
surroundings is obvious in cities which are in the process of rapid urbanization , but the IW
distribution changes little overtime in developed cities.