城市扩张对城市热岛效应影响的计量分析——以成都市为例

Quantitative analysis to the influence of urban heat island effect from urban sprawl:a case study of Chengdu City

逻辑因果关系是自然现象及规律的主要表现。从因果关系出发,通过计量分析的方法,量化"城市扩张会导致城市热岛效应"笼统而定性的结论。研究发现,协整分析和误差修正模型的结论表明城市热岛效应与城市扩张存在长期均衡关系,但有短期波动,且长期弹性大于短期弹性,说明城市热岛效应的累积效应明显;格兰杰因果检验发现,短期内城市扩张是城市热岛效应的格兰杰原因,而在长期这一结论并不成立;结合脉冲响应分析和我国城市建设的特征可判定短期与长期的分界点为4-5年,这与我国经济社会发展的五年期规划吻合,也与城市绿化的常选植被成长期吻合。

In the process of exploring of natural law, causality always plays very important role. With analysis of time series and spatial data retrieving, this essay quantifies the gener al qualitative conclusion of ＂urban sprawl lead to urban heat island effect＂. It shows that, in the aspect of time, urban heat island effect and urban sprawl has a long - term equilibrium relationship but has a short - term fluctuation, and the long - term elasticity is greater than short - term elasticity after the analyses with co - integration test and error correction model. It meansthat accumulation effect of urban heat island effect is apparent. And urban sprawl is the Granger cause of urban heat island effect in short - term but not in long - term after a causality test. Combining analysis of impulse response and the characteristic of city construction in China, this essay judges that the dividing point of long - term and short - term is about 4 - 5 years, this phase fit to the five - year plan in China and the growth period of vegetation chose for urban greening.