职住地建成环境对轨道交通通勤行为的非线性影响机制研究——以武汉市为例

Non-linear influencing of built environment of residence and workplace on rail transit commuting behavior:Taking Wuhan City as an example

改革开放以来中国大城市快速蔓延导致了职住分离及交通拥堵等问题,倡导轨道交通等绿色交通方式出行成为大城市缓解通勤压力的重要手段。当前研究主要以居住地作为地理背景考察建成环境对轨道交通通勤的作用,但较少探索就业地建成环境的影响。本研究以武汉市为例,通过189个轨道站点的刷卡数据识别轨道交通通勤人员并构建通勤出行链,通过梯度提升决策树(GBDT)解析职住地涉及建成环境和轨道站点的30个特征因素对通勤客流量和通勤时间的非线性影响机制。研究发现:①居住地通勤客流量表现为较集中的点状分布,就业地通勤客流量则呈现显著的“中心-外围”结构,职住地两端通勤时间的空间格局均呈中间低、外围高的分布特征;②职住地周边建成环境因素对轨道交通通勤客流量和通勤时间普遍存在非线性影响及阈值效应,整体而言居住地建成环境的相对影响程度高于就业地,但就业地“公司企业数”是影响通勤客流最重要的要素,就业地“与城市中心距离”则是影响通勤时间的首要因素;③职住地周边同一建成环境因素,对于通勤客流量和通勤时间的影响可能截然相反,这与城市轨道交通网络建设和社会实际发展状况相关。研究结果可以更好地理解职住地建成环境与轨道交通通勤行为的关联,有助于促进城市轨道交通和城市职住空间的协调发展。

Since the reform and opening up,the rapid expansion of Chinese city leads to the separation of occupation and housing and traffic congestion.Rail transit is an important means of relieving commuting pressure in cities.Current studies mainly explore the effect of built environment on rail transit commuting based on the geographical background of residence,but less explore the effect of built environment at workplace.Taking Wuhan City as an example,this study identified rail transit commuters and constructed commuter travel chain through smart card data of 189 stations.Gradient Boosting Decision Tree(GBDT)was used to analyze the nonlinear influence mechanism of 30 factors,including the built environment of residence and subway station characteristics,on commuter ridership and commute time.The results show that:1)The commuter ridership in residential areas presents a centralized point-like distribution,and the commuter ridership in employment areas presents a significant“center-periphery”structure,and the spatial pattern of commuting time of residence and workplace presents a low distribution in the middle and high distribution in the periphery.2)All job residence built environment factors on the rail transit commuter ridership and commuting time is widespread nonlinear effect and the threshold effect,overall residence built environment relative influence degree is higher than the workplace,but the job the company formed in workplace is the most important factors affect the commuter ridership,the distance between workplace and city center is the most important element in commuting time;3)The same built environment factor of residence and workplace may have similar or opposite effects on the commuter ridership and commuting time,which is related to the construction of urban rail transit network and the actual social development.The results of this study can better correlate the built environment of dismissal residence with the commuter characteristics of rail transit,and contribute to the coordinated development of rail transit and urban employment-residential space.