Temporal equilibrium analysis on process of construction land expansion

The purpose of this study aimed to discuss the process of construction land expansion and its relationship with economic growth. Firstly, the definitions of temporal equilibrium of construction land expansion were discussed in this research, and an integration model was built up based on coefficient of variation and decoupling mode based on IPAT. The temporal equilibrium index was calculated by this model, and it reflected the temporal equilibrium posture of construction land expansion. Furthermore, the empirical analysis took Tongzhou in Jiangsu Province for an example, and its process of construction land expansion during 1986-2008 was analyzed. The following conclusions were drawn: 1)According to the evaluation results of the coordination between construction land expansion and economic growth in the view of decoupling analysis, at 1year scale in Tongzhou, the relationship between construction land expansion and economic development was in a weak decoupling state, and there were large changes of coordination index C, proving a poor coordination. 2) Using the co-integration analysis and VAR models, we measured the interaction response cycle of economic growth and construction land expansion. Results showed that the response period was 4 years. Thus, the time scale was relaxed to 4 years. Then the relationship between construction land expansion and economic growth remained in a weak decoupling state during the 7 time phase (1986-1990, 1990-1993, 1993-1996, 1996-1999, 1999-2002, 2002-2005, 2005-2008) and the coordination index C and C' both increased firstly and then decreased, indicating that there was a growing gap between the actual rate and ideal rate of the construction land expansion. 3) The temporal equilibrium index (E) of construction land expansion referred to C and its coefficient of variation (CV). CV of construction land's annual average growth rate was higher, and showed a tendency of increased volatility in Tongzhou. Combining the above analysis and calculation results of E, the investigation shows that E of construction land expansion in Tongzhou firstly appeared to decline rapidly, and then increased slightly within a small margin, holistically indicating that its temporal equilibrium of construction land expansion was not optimistic. Many factors would affect the change of E. We concluded there was close contact between the changing trend of E and both economic growth characteristics and relevant national land use policy's implement. Finally, this paper has found that the model can depict the changes of coupling process between construction land expansion and economic growth, which provides scientific new ideas for understanding the process of regional construction land expansion.