The Impact of Urbanization Policy on Land Use Change: A Scenario Analysis

Cities 28 (2011) 147–159

Yuzhe Wua, Xiaoling Zhang, Liyin Shen

Resumed by Pindo Tutuko

Abstract

The rapid urbanization has led to extensive land use change particularly in those developing countries.

This paper introduces a dynamic systems based method for assessing the impacts of urbanization policy on land use change with reference to the urbanization practice in China. Four typical policy scenarios are identified in implementing urbanization in China, including 

1. Balanced development driven by planning
2. Uneven development driven by planning
3. Balanced development driven by market
4. Uneven development driven by market and their impacts on land use change.

They are analyzed through a dynamic system model. 

Introduction

• Urbanization has increased in transport provision and development of regional economies. Increased demand for urban land has led to a diversification of land use patterns (for example, industrial, residential, and infrastructure uses, as well as ecological conservation).
• The number of mega-cities (>1 million population) increased from 13 in 1978 to 56 in 2007 (National Bureau of Statistics of China, 2007).
• Land use change is closely related to the socio-economic and ecological environment.
• A large a mount of agricultural land to be developed as construction land.

Research Method

• The system dynamics method, the model contains urbanization, social, economic, environmental and land use subsystems.
• System dynamics (SD) was created in the form of a computer simulation model, comprising five modules of world population, industrialization, pollution, food production and resource depletion - to forecast the exhaustion of the world resources.

Study Area

The year 2002 marked the opening of the highway from Jinyun County to Hangzhou, the capital of Zhejiang Province – greatly improving access to the Jinyun County. The urbanization level has also been accelerated, with an urban population of 33.1% of the total population in 2000 increasing to 46.3% by 2007

The SD model for land use change

The first stage in constructing an SD model is to define the system boundary.

It have a boundary comprised of urbanization (U), social (S), economic (E), environmental (EN), and land use (LU) subsystems.

Economic development levels in urban areas are generally higher than that in rural areas (income in urban areas is higher than in rural areas). Results in the continuous movement of the rural population to metropolitan areas.

Framework

• Dynamic modeling flow chart of land use change system in the perspective of urbanization.
• The urbanization process curve (a) curve ‘S’ and (b) standard pattern based on curve ‘S’.
• The key variables and their interactions:To determine the validity of the logic of the SD model, suitability of the proposed preliminary variables and terminology.
• Key variables for the subsystem-urbanization (U)
• Policy scenarios for the urbanization process; This describes the process of urbanization with its initial slow development followed by rapid growth, smooth development, and finally saturation.

The Four Policy Scenario

Lishui, Jinyun comprises a rural County, while Liandou is an urbanized centre within the City. The two alternative urbanization policies of balanced development and unevenly coordinated development can be adopted by Lishui City in allocating urban land use and that will affect the urban development of Jinyun County. If a balanced development is adopted, more urban land use quota will be allocated to each of the eight counties including Jinyun County, thus increasing the urban land use quota per capita for Jinyun County.

Urbanization system-Urbanization Policy-Land use system

The Government assumes an important role in the process of urbanization by adopting planning policies.

The question now is how to simulate these four policy modes? In the urbanization system, a policy decision process, the urbanization policy subsystem is used. Also, several factors determine the policy modes.

 Simulation of policy scenarios
Data for the simulation process and model validation

• The data for 1996 were used as the initial value to test the model and the variation between the simulated and actual values were defined as errors.

Simulation results

• By using the validated SD model of land use change, a comprehensive simulation was conducted to demonstrate the impacts of the four scenarios in Jinyun County. The 2004 data were set as the initial value of model.

The following conclusions

1. All four policy scenarios cause reduction in agricultural land use from year 2004 to year 2020. This reduction rate is significant before 2010. However, the reduction impacts of policies 1 and 2 are less than that from policies 3 and 4 after the year 2010.
2. All the four policy scenarios result in increased urban construction land from 2004 to 2020. 

However, it is interesting to note that policies 3 and 4 cause much higher increase rates policies 1 and 2. 

• In terms of the changes in open land use, all the four policy modes result in an increase in this type of land use before 2010, but with it decreasing after 2010. 
• Nevertheless, the influences of policies 1 and 2 on the reduction of open land use are less than those of policies 3 and 4.

Summary

• The simulation results indicate that the amount of agricultural land will follow a downward trend, urban construction land will continue to increase, and open land will rise before the year 2010 but decrease afterwards.
• With market-driven policies (Scenario 3 and Scenario 4), urban construction land area tends to grow until 2010, while the agricultural land and open land areas have a decreasing trend there after. 
• Considering the impact of the planning-driven policies (Scenario 1 or Scenario 2), due to the rigid requirements of China’s arable land protection policy, a minimum amount of agricultural land needs to be maintained. The urban construction land areas grow slowly by the year 2010 and open land decreases slightly after the year 2010. 
• The land use is expected to change over the next 10 years.

Conclusion

• Urbanization is one of the major driving forces contributing to land use change. 
• Particularly in developing countries where changes in land use are expected to be driven by urbanization policy. 
• In particular, urban construction land use is anticipated to expand continually with an increasing urban population.
• The optimization of land resource allocation, particularly for urban construction, is vital to improved welfare and achieving sustainable development. 
• The method presented in this paper aims to help decision makers to predict the likely consequences of their decisions, thus enabling adjustments to be made before policy implementation. 
• SD model can be used to monitor the land use change and act as a decision-making tool for assisting the development of urbanization policy.

Source: The impact of urbanization policy on land use change: A scenario analysis