26 de julho de 2012

Urban Sprawl in China – Land Use Change at the Transition from Village to Town - 1ª Parte

Veronika Praendl-Zika
Senior Research Fellow Oikodrom – The Vienna Institute for Urban Sustainability

1 Introduction

China is currently experiencing rapid changes mostly noticeable in big cities in terms of economic growth with effects on social, environmental, infrastructional and political systems there. As a consequence “...China is undergoing the most rapid and largest process of urbanization all over the world” (Paulussen 2003). ... This tendency will deeply impact the social, environmental and economic situation of the whole country.

2 Background – Urban Sprawl in China

The poor rural situation is one of the reasons why migration to prosperous cities has reached uncontrolled dimensions. “The most rapid growth has been forecasted in medium sized cities of the coastal region with a population of 500,000 up to 1 Mio.: in less than 10 years the urban population will double” (Paulussen 2003). This fact implicates that further expansion of cities leads to urban sprawl. Besides cities do not only spatially grow because of the increasing population but also because of an ever increasing land demand per inhabitant: more living space, more working space, more cars, consequently more space for road traffic but also for new urban facilities – like shopping malls, entertainment facilities, airports etc.

Tendencies in land use
Currently changing land use in peri-urban areas in China is subject to different influences. On the one hand land use planning is part of a higher regional planning but on the other hand big national and international investors achieve construction permits very quickly. Peri-urban zones in China have gained economic importance and attract domestic as well as foreign investment. “Simply speaking, peri-urban areas are where the forces of globalization and localization intersect” (Webster 2002). As a consequence agricultural communities are often forced to adjust to an urban or industrial way of life in a very short time. This tendency affects an ever increasing number of villages and amount of land and following Webster the peri-urban zone sometimes extends as far as 150 km from the core city, or as in the Chinese case as far as 300 km.
Moreover informal housing and illegal land captures by migrants lead to uncontrolled construction activities and cause further dissipation of space.

From an economic point of view peri-urban zones in China often end in a stagnating development due to a lack of comprehensive long term strategies. “Because so much land is involved, the strength of drivers of peri-urbanization may decline in some areas and...it appears that a new uneasy equilibrium that is neither totally urban nor suburban will result in many cases” (Webster 2002). Such tendencies may leave rural structures in some parts of the country economically, socially and ecologically imbalanced.

Therefore new strategies should include urban as well as rural development with agricultural concepts in combination with industrialisation plans to complement one another.

3 Impacts of Urban Sprawl on Agriculture

Effects of arable land reduction:
As China’s population concentrates in the agricultural regions in the east urban sprawl takes primarily place on arable land and causes big losses on fertile soils. “In China, urban sprawl significantly reduced the land area devoted to agriculture. As a result, China lost its independence in food production” (Olson 1996)

Consequently the loss of arable land has several dimensions:
- loss of the economic soil potential, primarily for farmers as their basis for subsistence and income, then forced to accept any other job, if available
- further loss of economic soil potential also means for China that food security cannot be guaranteed anymore and leads to dependency from other countries
- loss of the ecological soil potential: once the soil is sealed it is irretrievably lost for cultivation for decades
- loss of the ecological soil potential also includes further reduction of biodiversity, deep impacts on eco-systems and on the appearance of landscape, the change of micro-climatic conditions etc.

Furthermore the absolute loss of arable land is aggravated by erosion and desertification which are major hazards in China and by the tendency of changing nutrition habits towards more land consuming products as meat or milk.

Valuation of land and soil potentials
In this context the valuation of land and soil potentials is an interesting question and shows the priorities of a state at the interface of economic soil economy and ecology. The economic land potential in urban and peri-urban areas is much higher than the potential because the ecological soil potential is not yet valuated adequately.

Priorities and decisions in land use
For a country like China soil and land should not only be considered as economic resource but dimensions as nature, landscape, biodiversity, typical ecosystems etc. should reach higher importance. Regional land use plans integrating these dimensions in appropriate standard can be a useful instrument and contribute to environmental quality.

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