Rational Scale of Urban Land Expanding in Taicang City

The purpose of the paper is to explore a method for measuring the reasonable scale of urban land regarding a target period of land use planning to further provide a scientific basis for solving the conflict between socio-economic development and farmland protection.Taking Taicang city as an example,methods of the C-D productive function and the cost-effectiveness curve were used to analyze the condition of reasonable urban land use scale.The urban land scale measurement model was estimated by the method of weighted least squares.The reasonable area scales of urban land in target years were calculated through the method of scenario analysis under different economic development conditions.Result shows that reasonable scale of cantonal urban land in Taicang city is 4805.61 hm2 in 2015 and 5495.88 hm2 in 2020 if the value of ecosystem services is considered under the scenario of moderate development of socio-economy.While under the scenario of rapid economic development and the value of ecosystem services,the reasonable scale of urban land in 2015 is 5133.36 hm 2 and 6161.38 hm 2 in 2020.However,if the value of ecosystem services is not taken into account,the reasonable scale will be 5907.38 hm 2 in 2015 and 6756.93 hm 2 in 2020 under the scenario of moderate development of economy.It concludes that reasonable scales of urban land in target years could be calculated by using the methods of Econometrics and Scenario Analysis.