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Urbanization and

Urban System Dynamics

Professor Xuemei Bai

Fenner School of Environment andSociety, ANU

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Figure 2. The change in the human

enterprise from 1750 to 2000 (28).

The Great Acceleration is clearly

shown in every component of the

human enterprise included in the

figure. Either the component was

not present before 1950 (e.g., foreign

direct investment) or its rate of

change increased sharply after 1950

(e.g., population).

(Source: Steffen et al, 2007)

Urbanization as key

indicator for accelerating

human enterprise

1. Urbanization in the Anthropocene

More than half the

Earths population are

urban dwellers

Cities as the center for

economic growth,

innovation, resource

use, and

environmental impacts

Battle for sustainability

to be won or lost in

cities

Urban vs rural population(Source: Grimm et al 2008) Map 5: Growth rates of urban agglomerations, 1970-2011. These maps indicate

that the annual growth rates of urban agglomerations in the past (1970-2011 period)

were higher than the growth rates that are projected for the future (2011 to 2025period). The growth of urban agglomerations will slow down, as many of them have

already reached a population of 1 million or more or have become mega-cities with 10

or more million inhabitants.(Source: United Nations, Department of Economic and Social Affairs, Population Division: World Urbanization

Growth Rates of Urban Agglomerations, 1970-2011.

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Figure 3 Rapid urban

expansion of Shenzhen

City from 2000 to 2007

based on remote

sensing image

interpretation. Redcolor for urban land,

yellow for bare land,

green for land withvegetation, blue for

water body.

ETM+ image on Nov. 1st 2000, TM

image on Sep. 15th 2000, ETM+

SLC-off composite data on Dec.7th and Nov. 30th 2007 are used

for this comparison.

(Bai et al, forthcoming)

1. Background

Neck breaking speed in building

15 storey fastest

building of hotel built

in just six days- world

record, Changsha,

China (http://ddlax.hubpages.com/hub/

15-storey-hotel-built-in-just-six-days)

30-story building built

in 15 days (http://www.youtube.com/watch?

v=Hdpf-MQM9vY&annotation_id=annota

tion_418374&feature=iv)

220-story 838m

World tallest building

in 90 days?12

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And Demolishing

Average building lifespan

10+ in Shenzhen

80% of world heavy cranes

in coastal China

40% of construction

materials used in China

Construction material

demand will exceed supply(Shen et al, 2005)

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Five Lake Hotel in Nancang City, 13years old, blasted on Feb. 6th, 2010.

Change of ownership, upgrading.

The Bund Community in Wuhan, 4 years

old, blasted on March 30th, 2002. Violation

of flood regulation plan.

http://www.zerohedge.com/article/china-proudly-demolishing-

buildings-completed-pursuit-great-housing-bubble-perpetual-engine

2. Drivers and Impacts of Urban Growth

Primary driver:

- Job opportunity and aspiration for better life- Push and pull factors

Policy factor:- Concurrence of urbanization, industrialization and economic

growth

- Significant urban contribution to national economy- High income countries often have higher urbanization level

=> National policy to promote urbanization for economic growth

Does urbanization bring about economic growth?(Bloom et al, Science, 2008)

Urbanization as multifaceted phenomenon: Demographic

Landscape

Social

Cultural

Political/institutional

Environment

Demographic urbanization data known to beproblematic, and lacks comparability across countries

Demographic indicator not sufficient to deny causalrelationship between urbanization and economic growth.(Bai et al , 2012)

Urbanization is more than people

moving into cities!

Figure 2 Spatial distribution of Chinese cities included in analysis.Panel U1 (1990-1998) consists of 174 cities.

Panel U2 (1997-2006) consists of 135 cities.

Panel U3 (1990-2006) consists of 121 cities that appear in both U1 and U2 panel.

(Source: Bai et al, EST, 2012)

2. Drivers and Impacts

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Figure 4 Average annual growth of GDP per capita, built-up area,

and population of 135 Chinese cities during 1997-2006.

(Source: Bai et al, EST 2012)


Positive Feedback

1)Larger cities tend to gain more income and richer citiestends to expand more

2) There is a long-term bi-directional causality betweenurban built-up area expansion and GDP per capita atboth city and provincial level, and a short-term bi-directional causality at provincial level.

3) A positive feedback between landscape urbanizationand urban and regional economic growth in China.

(Bai et al, Environmental Science&Technology, 2012)


Policy Implications

1) Urbanization, if measured by a landscape indicator,does have causal effect on economic growth in China,both within the city and with spillover effect to theregion.

2) Urban land expansion is not only the consequences ofeconomic growth in cities, but also drivers of such

growth.3) Under its current economic growth model, it might be

difficult for China to control urban expansion withoutsacrificing economic growth.

4) Chinas policy to stop the loss of agricultural land, forfood security, might be challenged by its policy topromote economic growth through urbanization.

- (Bai et al, Environmental Science&Technology, 2012)


Urban landuse is often surrounded by

arable land. Beijing-Tianjin-Tangshan

area, China (shown in 10km radius in the

figure). (Source: Tan et al 2005)

Disproportionate Impact on Arable Land

In China, up to 80% of

all agricultural land

loss over the last

decade was convertedinto urban landuse.

Between 1997 and

2006, more than

12,000sqkm of land

was converted into

urban built up area.(Bai et al 2012)

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Currently about 1% of earth surface is urban.

Some forecast suggest this could be tripled by

2030.

(Source: United Nations, Department of Economic and Social Affairs, Population

Division: World Urbanization Prospects, the 2011 Revision. New York 2012)

Implications for Agriculture

While the absolute amount doesnt seem

significant, urbanization has significant

implications in terms of:

Direct impact on the amount of arable land

Strong, fundamental drivers

Indirect impacts on productivity and rural community

Changed quantity and structural mix of demand for

food

Stronger pressure on food production concentrated tosome vulnerable regions such as China and India

Bai Crawford Fund Conf., Oct

9th, 2012

Fig. 5 Transformation of four communities over past 6 decades. (Huang et al,

Environmental Science and Policy, 2 012)

Urbanization Impacts on Rural Community

(Huang et al, Environmental Science and Policy, 20 12)

Changing Vulnerability of rural community in relation to

landuse change

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But in other areas, where

the locals can seize the

opportunity, tremendous

increase in social/economic

capital in peri-urban areas.

(CCICED, 2012)

Eco-tourism in Chengdu rural villages

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Urbanization Impact of on Rural Community

- Five Golden Flowers in Chengdu - Urban EcosystemsCities as driver and responder to environmental change

(Grimm et al 2008, Science)

3. Urban Processes and Dynamics

Global Impacts of Cities

Although urban population growth over the past century

occurred on less than 3% of the Earths surface, theimpact has been global, with

78% of carbon emissions,

60% of residential water use, and 76% of wood used for industrial purposes attributed to cities.

(Source: Grimm et al, Science, 2008)

3. Processes and Dynamics

Urban System

Input

NaturalResource (Food,Energy, Water,Other Materials)CapitalInformation

Urban Systems Structures

and Functions

Urban Land and WaterEcosystem ServicesUrban InfrastructureDistribution of GoodsProvision of Urban ServicesIndustrial ProcessesUrban Planning

Urban GovernanceUrban life style

Urban System

Outputs

Industrial Products andServicesKnowledgeWastes and Other

Emissions

Urban Systems Performance Indicators

Social (e.g. employment, liveability, health and well being, culture and heritage, equality)Economic (e.g. competitiveness, productivity)Environmental (e.g. air and water pollution level, noise level, resource efficiency etc)Governance (e.g. participation and inclusion)

Figure 2 Integrated urban metabolism and urban system performance indicators

(Source: Bai and Schandl, 2011. In RutledgeHandbook of Urban Ecology, 2010)


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Cities as Open System

Can we live off solar energy in cities? (According to Global Energy Assessment, 2012) ?%

External dependency:

Household Consumption based CO2 emission

accounting in Xiamen city:

70% - upstream to provide for cities

17% - urban service & infrastructure

13% - emission from direct activity

(Lin et al, PLoS ONE 2013)

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Discharge as solidhuman excreta

Sludge

dischargeDischarg

e as

treated

Marginally left in human

body (ignored)

Reclaimed

water

To landfill or

a ricultural

P fertilizer

input into

Food

Edibl

e

Inedible Solid

P inflow intourban system

through food

consumption

Food waste

Pass throughouturban area and to

P remained

in urban

area

Non-urban

Urban

Landfill

Discharge as

untreated sewa eP flow outside

Othersremainedin urban

Figure 2 Conceptual model of urban dietary P flow into and out of

urban system and mass balance calculation.

(Source: Li, Bai et al, Journal of Industrial Ecology, 2011)


Figure 6 Relationship between per capita disposable

income of urban residents and indicators related to

dietary P flow in provincial capital cities of China

(data for the year 2006).

(Source: Li, Bai et al, Journal of Industrial

Ecology, 2011)

(B)

(E

)

(C) (D

)

(A)

3.ProcessesandDynamics

Table 3-1 Causes and impacts of major types of ur ban environmental issues

Type Typical Issues Causes Major Impacts

Spatial Extend of

Impacts

Type I:

Poverty

related issues

Low access to safe

water, lack of

sanitation facilities,

organic pollution of

water bodies

Low infrastructure,

rapid urbanization,

income disparity

Sanitation related

health impacts, such

as diaries, infections

local

Type II:

Rapid growth

related issues

Air poll ution (SOx,

particulate etc), water

pollution (heavy

metallic subjects,

BOD, COD)

industrial solid waste

pollution, etc.

Rapid

industrialization, low

rate of emission

treatment, lack of

effective management

typical industrial

pollution disaster,

Minamata Disease,

Onsan Disease;

deterioration of

regional ecosystem,

local and regional

Type III:

Wealthy

lifestyle

related issues

CO2 emission, NOx

concentration,

municipal waste,

Dioxin, etc.

High consumption

lifestyle, low local

incentive for

improvement

Global warming,

chemical ingredient

and dioxin caused

abnormality in infant,

over-extraction of

resources, etc.

regional and global

(Source: Bai and Imura, 2000)


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SO2 concentration in Korean and Japanese cities

0.000

0.050

0.100

0.150

0.200

0.250

0.300

1950 1960 1970 1980 1990 2000 2010

Year

SO2concentration(mg/m3)


(Source: Bai 2003)

Urban Environmental Evolution (1)

Cities are complex systems subject to

constant change, the process of which can be

viewed as a dynamic evolutionary process

Urban environmental profiles of cities are

diverse, but there are certain commonalities

in the evolutionary trajectories among

different cities (Source : Ba i2003)


Urban Environmental Evolution (2)

However, the environmental evolution of

cities exhibit a strong non-linearity in their

trajectories, instead of following a fixed,

stylized pattern;

Each trajectory is shaped by a unique

combination of endogenous and exogenous

forces, reflecting both pressures from outside

the system and the responses from within the

city. (Source : Ba i2003)


4. Urban Sustainability Experiments and

Transition

If cities are evolving systems, is it possible to

intervene and alter the future trajectory towards

sustainable end?

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Changing System of Practice

Change is always challenging!

Inertia

stickiness

path dependency

Lock-in

Nevertheless, there are front-runners and

successful examples

Large number of urban best practicesdocumented

4. Experiments and Transition

Solar energy use in Rizhao, China


Sustainability Experiment

Sustainability experiments are planned initiatives

that embody a highly novel socio-technical

configuration likely to lead to substantial

(environmental) sustainability gains.

Small initiatives in which the earliest stages of a process of

socio-technical learning takes place.

Typically bring together new networks of actors with knowledge,capabilities and resources, cooperating in a process of learning

(Berkhout et al, 2010)


Single Case vs. Multiple Case

Single case learning often treated as too context

specific or anecdotal in academic debate

Lack of systematic, comprehensive analysis

attempting to identify commonalities across largenumber of individual cases

The need for understanding key characteristics

and emerging common patterns, and extracting

transferable knowledge across cases


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Research Questions

What contributes to the success of a goodpractice?

Are there commonalities and emerging patterns

across cases?

What are the determining factors and mechanisms

shaping these patterns?

What are the sound analytical approaches for

identifying them?

(Bai et al 2010)


Pathway ofExperiments

Triggers

ActorsBarriers

Linkage

s

Analyzing innovative practices in urban sustainability:

Conceptual framework

(Source: Based on Bai et al, Environmental Science and Policy,

2010)

Conceptual Framework4. Experiments and Transition

Findings from 30 Urban Sustainability

Practices in Asia

About half of all cases either multiplied or up-scaled tochange system of practice

Political aspect prominent for both success and failure,e.g. policy change as trigger, local government role asmain actor, state government support, institutionalaspect as major barrier

Technology or cultural aspect seldom identified as majorbarrier

Many international donor funded projects tend to stay asindividual experiment, some times multiplied but seldomup-scaled to change system of practice


In Summary

Cities as human-dominant, complex, dynamic,evolving systems

Their internal and external dynamics notnecessarily well understood, e.g. urban-

agriculture interaction. Presents enormous challenges as well as

opportunities for sustainability

The need to focus more on the role ofsustainability practices and experiments

What happens in cities will, to a large extent,define human-environment interaction in

Anthropocene

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